JP2019131720A - Plasticizer and resin composition containing the same - Google Patents

Abstract

To provide a biodegradable plasticizer and a resin plasticization method useful for plasticization of resin, and a biodegradable resin composition containing the plasticizer and a molding thereof.SOLUTION: Relative to 100 pts.wt. of a thermoplastic resin such as a polyester resin, added is a biodegradable plasticizer, which is an oligomer of 3-hydroxyalkanoic acid (e.g. 3-hydroxybutyric acid) or an oligomer its carboxyl group terminal alkyl-esterified at a rate of 0.1-50 pts.wt., to plasticize the resin.SELECTED DRAWING: None

Description

  The present invention relates to a plasticizer (or biodegradable plasticizer) formed of a homopolymer or copolymer oligomer of 3-hydroxyalkanoic acid such as 3-hydroxybutyric acid (3-hydroxybutanoic acid or 3HB), and this plasticizer. The present invention relates to a method for adding resin to promote plasticity, a resin composition (or biodegradable resin composition), and a molded article thereof.

  From the viewpoints of environmental conservation and the establishment of a sustainable society, it has been considered to convert part or all of plastic raw materials into biomass, and bio-based plastics (biodegradable plastics) are being used. Known biodegradable plastics include polybutylene succinate (PBS), polybutylene succinate adipate (PBSA), polybutylene adipate terephthalate (PBAT), polycaprolactone (PCL), and polylactic acid (PLA). However, many of these biodegradable plastics have the problem of low crystallization speed and low mechanical properties. In order to solve such a problem, Japanese Patent Application Laid-Open No. 2000-17163 (Patent Document 1) describes an amorphous polymer (A) having an L-lactic acid unit as a main unit in order to improve molding processability, It is described that a highly crystalline polylactic acid stereocomplex polymer composition is obtained by melt blending with an amorphous polymer (B) mainly composed of D-lactic acid units. In addition, JP 2017-101256 A (Patent Document 2) discloses a technique for improving the crystallization speed to improve the molding processing speed and minimizing the crystal to suppress the change in mechanical properties of the molded article with time. The addition of pentaerythritol as a nucleating agent is described.

  On the other hand, many biodegradable plastics can be effectively decomposed only under aerobic conditions and cannot be decomposed at a sufficient rate under anaerobic conditions. H. Yagi et al., Polymer Degradation and Stability 110 (2014) 278-283 (Non-patent Document 1) evaluates the biodegradability of various biodegradable polyesters under anaerobic conditions, and includes PLA, PCL, and PBS. As compared with the above, it is described that polyhydroxybutyric acid (PHB) exhibits high degradability under anaerobic conditions. As described above, among the biodegradable plastics, PHB is a few bio-derived polymers that are efficiently decomposed under anaerobic conditions, but has not been put into practical use because of its hard and brittle nature.

  JP-A-63-269899 (Patent Document 3) discloses that a microorganism having a PHB-producing ability is cultured in the presence of valeric acid, and a copolymer having a large ratio of valeric acid to butyric acid in the cell (D -(-)-3-hydroxybutyrate is 50 mol% or more and D-(-)-3-hydroxyvalerate is a random copolymer having 50 mol% or more). Although this copolymer can improve the copolymerization with valeric acid (by internal plasticization) and impact resistance of PHB, the characteristics of the copolymer are determined at the time of synthesis, so the biodegradability is maintained. However, the properties of the copolymer cannot be adjusted.

  Japanese Unexamined Patent Publication No. 2000-289104 (Patent Document 4) describes a composition obtained by adding polycaprolactone to PHB to form a composite. However, in this composition, polycaprolactone which is externally plasticized deteriorates biodegradability, particularly degradability under anaerobic conditions.

  As described above, these documents have a high biodegradability (especially biodegradability under anaerobic conditions) and can easily plasticize a thermoplastic resin to adjust the physical properties of the resin. High plasticizer) is not described.

In JP-A-2015-29484 (Patent Document 5), a predetermined microorganism is cultured in the presence of alcohol, the weight average molecular weight is as low as 5,000 to 40,000, and the carboxyl group terminal is a C _1-6 alkyl ester. The use of modified polyhydroxyalkanoic acids as crystal nucleating agents for polyhydroxyalkanoates is described. This document describes a low molecular weight (number average molecular weight 9000, weight average molecular weight 20000) and carboxyl group based on 100 parts by weight of poly (3-hydroxybutyric acid-co-3-hydroxyhexyne acid) (PHBH). It is described that the crystallization speed is improved in a composition obtained by melt-mixing 1 part by weight of poly (3-hydroxybutyric acid) (sPHB) having terminal ethyl esterification.

JP 2000-17163 A (Claims, [0016]) JP 2017-101256 A (Claims, [0008]) JP-A 63-269989 (Claims, Means for Solving Problems, Action) JP 2000-289104 A (Claims) JP 2015-29484 A (Claims, Examples)

H.Yagi et al., Polymer Degradation and Stability 110 (2014) 278-283 (Table 1)

  Accordingly, an object of the present invention is to provide a plasticizer having high biodegradability and capable of plasticizing a thermoplastic resin, a resin composition (or biodegradable resin composition) containing the plasticizer, and a molded product thereof. There is.

  Another object of the present invention is a plasticizer (or biodegradable under anaerobic conditions (anaerobic biodegradability)), which has a high plasticizing effect on a thermoplastic resin and can easily adjust the physical properties of the thermoplastic resin. It is to provide a degradable plasticizer), a resin composition (or a biodegradable resin composition), and a molded body thereof.

  Still another object of the present invention is to provide a plasticizer having a high compatibility with a thermoplastic resin (for example, a biodegradable resin), a high melt moldability, and an easy composite, and a resin composition containing the plasticizer, The object is to provide the molded body.

  Another object of the present invention is to provide a method for improving plasticization of a thermoplastic resin using the plasticizer.

  The present inventors pay attention to the extremely high biodegradability (especially anaerobic biodegradability) of poly (3-hydroxyalkanoic acid) such as poly (3-hydroxybutyric acid) (PHB) existing in nature, When plasticization of a resin (in particular, a thermoplastic resin, for example, a biodegradable plastic such as PHB) was examined, an oligomer of 3-hydroxyalkanoic acid such as 3-hydroxybutyric acid (3HB) or an ester thereof was used as the thermoplastic resin. It has been found that when it is added, it has high compatibility with thermoplastic resins, functions effectively as a plasticizer, improves biodegradability (especially anaerobic biodegradability) and moldability, and has completed the present invention.

  That is, the plasticizer (or biodegradable plasticizer) of the present invention is formed of a 3-hydroxyalkanoic acid homopolymer or copolymer oligomer, and has a free carboxyl group or alkoxycarbonyl group (carboxyl group alkylated as a terminal). Ester group).

3-hydroxyalkanoic acid is a compound in which the 2-position is a methylene group (active methylene group), for example, at least 3- _{hydroxyC 4-12} alkanoic acid, such as 3-hydroxybutanoic acid (3-hydroxybutyric acid or 3HB). May be included. 3-hydroxybutanoic acid may be in the R form. That is, 3-hydroxyalkanoic acid may contain at least an R-form of 3-hydroxybutanoic acid. The terminal carboxyl group may be modified to form a C _1-10 alkoxycarbonyl group. Further, the molecular weight of the oligomer may be, for example, about a number average molecular weight of 180 to 3000.

  Such a plasticizer is useful for plasticizing a resin (for example, a biodegradable resin having at least an ester bond or an amide bond as a linking group, a hard and brittle resin, or the like). Therefore, the present invention provides a resin composition (biodegradable resin composition) containing a resin (such as a biodegradable thermoplastic resin) and the plasticizer (or biodegradable plasticizer); a resin (biodegradable heat). A method of improving the plasticity of the resin (or a method of plasticizing) by adding the plasticizer (or biodegradable plasticizer) to a plastic resin or the like is also included.

  The resin may contain a biodegradable resin, and may usually contain at least one selected from a polyester resin, a polyamide resin, a polyesteramide resin, a polyester carbonate resin, and a polycarbonate resin. For example, the resin may contain a homo- or copolymer of hydroxyalkanoic acid (eg, 3-hydroxyalkanoic acid). The amount of the plasticizer used may be, for example, about 0.1 to 50 parts by weight with respect to 100 parts by weight of the resin.

  The present invention further includes a molded body formed of a resin composition (or a biodegradable resin composition).

  In the present specification and claims, the term “hydroxyalkanoic acid” may be used in the sense of including the corresponding lactone and reactive derivative.

  In the present invention, since a plasticizer containing an oligomer obtained by polymerizing a monomer containing at least 3-hydroxyalkanoic acid can be formed, high biodegradability (not only aerobic conditions but also anaerobic conditions) is provided. In addition, a resin (for example, a thermoplastic resin including an ester bond, particularly a hard and brittle biodegradable resin) can be effectively plasticized, and the plasticity of the resin can be improved. In particular, the biodegradability (anaerobic biodegradability) under anaerobic conditions is high, and the plasticizing effect on a resin (such as a thermoplastic resin) is also high. Therefore, the physical properties of the resin can be easily adjusted. Furthermore, it has high compatibility with thermoplastic resins, can improve melt moldability with high melt fluidity, and can be easily made into a composite.

[Plasticizer (biodegradable plasticizer)]
The plasticizer of the present invention contains a homopolymer or copolymer oligomer of 3-hydroxyalkanoic acid and has biodegradability (particularly anaerobic degradability). Therefore, the plasticizer of the present invention may be referred to as a biodegradable plasticizer. Examples of 3-hydroxyalkanoic acid (or 3-hydroxyalkanecarboxylic acid) include, for example, 3-hydroxypropanoic acid, 3-hydroxybutanoic acid (3-hydroxybutyric acid), 3-hydroxypentanoic acid (3-hydroxyvaleric acid), 3-hydroxy-3-methyl-butanoic acid (3-hydroxyisovaleric acid), 3-hydroxyhexanoic acid, 3-hydroxyheptanoic acid, 3-hydroxyoctanoic acid, 3-hydroxynonanoic acid, 3-hydroxydecanoic acid, etc. And 3-hydroxy C _4-12 alkanoic acid (3-hydroxy C _3-11 alkane-carboxylic acid).

The 3-hydroxyalkanoic acid as a reaction component (raw material) may be a corresponding lactone such as β-butyrolactone, β-valerolactone, β-pivalolactone, and the like. Furthermore, 3-hydroxyalkanoic acid as a reaction component (raw material) is a reactive derivative such as an acid halide (acid chloride or the like), a lower alkyl ester (for example, a C _1-4 alkyl ester such as a methyl ester or an ethyl ester), In particular, it may be a _C1-2 alkyl ester).

These 3-hydroxyalkanoic acids can be used alone or in combination of two or more. Among these 3-hydroxyalkanoic acids, at least 3- _{hydroxyC 4-12} alkanoic acids (for example, 3- _{hydroxyC 4-10} alkanoic acids, preferably 3-hydroxyC _{4- 8} alkanoic acids, more preferably 3-hydroxy C _4-6 alkanoic acids, especially 3-hydroxybutanoic acid) are used. The hydroxyl group of 3-hydroxyalkanoic acid may be a primary hydroxyl group, but is usually a secondary hydroxyl group in many cases.

  The biodegradable plasticizer can be formed of an oligomer obtained by polymerizing at least 3-hydroxyalkanoic acid as a monomer, that is, a single or copolymerized oligomer (oligo (hydroxyalkanoate)). As 3-hydroxyalkanoic acid, at least 3-hydroxybutanoic acid (first 3-hydroxyalkanoic acid) is often used, and 3-hydroxybutanoic acid (first 3-hydroxyalkanoic acid) is used alone. It may also be used in combination with a different 3-hydroxyalkanoic acid (second 3-hydroxyalkanoic acid). The ratio (molar ratio) between the first 3-hydroxyalkanoic acid and the second 3-hydroxyalkanoic acid is the former / the latter = 50/50 to 100/0 (for example, 60/40 to 99/1), preferably May be about 70/30 to 100/0 (for example, 75/25 to 97/3), more preferably about 80/20 to 100/0 (for example, 85/15 to 95/5). It may be about 85/15 to 100/0.

  The 3-hydroxyalkanoic acid may be either an optical isomer (R-form, S-form) or a racemate, and is preferably an R-form. In particular, 3-hydroxybutanoic acid is preferably R-form, and 3-hydroxyalkanoic acid preferably contains at least R-form of 3-hydroxybutanoic acid.

  Furthermore, the biodegradable plasticizer is a copolymer of 3-hydroxyalkanoic acid as the first hydroxycarboxylic acid (first monomer) and the second hydroxycarboxylic acid (second monomer). You may form with an oligomer.

  The second hydroxycarboxylic acid (second monomer) may be, for example, a hydroxycycloalkanecarboxylic acid (such as hydroxycyclohexanecarboxylic acid), a hydroxyarene carboxylic acid (such as hydroxybenzoic acid), or an alkyl ester thereof. Usually, it is often a hydroxyalkanoic acid or an alkyl ester thereof.

Examples of the hydroxyalkanoic acid include glycolic acid, 2-hydroxypropanoic acid (lactic acid), 2-hydroxybutanoic acid (2-hydroxybutyric acid), 4-hydroxybutanoic acid, and 2-hydroxypentanoic acid (2-hydroxyvaleric acid). 4-hydroxypentanoic acid, 5-hydroxypentanoic acid, 2-hydroxy-2-methyl-pentanoic acid, 4-hydroxyhexanoic acid, 6-hydroxyhexanoic acid, 6-hydroxyheptanoic acid, 7-hydroxyheptanoic acid, 8- Hydroxy C _2-15 alkanoic acid (particularly, hydroxy C _2-12 alkanoic acid) which may have a C _1-6 alkyl group such as hydroxyoctanoic acid, 9-hydroxynonanoic acid, 10-hydroxydecanoic acid, etc. It can be illustrated. As the second monomer, hydroxy C _2-6 alkanoic acid (eg, glycolic acid, lactic acid, hydroxybutyric acid, etc.) is often used. The hydroxycarboxylic acid as the second monomer may be an alkyl ester as in the first monomer, and corresponding lactones such as β-propiolactone, γ-butyrolactone, C _3-15 lactone _optionally having a di-C _1-12 alkyl group such as γ-dimethylbutyrolactone, δ-valerolactone, ε-caprolactone, etc .; may be an acid halide.

  The ratio of the first hydroxycarboxylic acid (first monomer) to the second hydroxycarboxylic acid (second monomer) is the former / the latter (molar ratio) = 50/50 to 100/0 ( For example, 65/35 to 99/1), preferably 70/30 to 100/0 (for example, 75/25 to 95/5), more preferably 80/20 to 100/0 (for example, 90/10 to 95). / 5), and usually 85/15 to 100/0 (for example, 80/20 to 90/10).

Such an oligomer (single or copolymer oligomer) may have a free carboxyl group (terminal carboxyl group), and the free carboxyl group (terminal carboxyl group) is modified by alkyl esterification to form an alkoxycarbonyl group. May be formed. Such alkoxycarbonyl groups include, for example, methoxycarbonyl groups, ethoxycarbonyl groups, propoxycarbonyl groups, isopropoxycarbonyl groups, butoxycarbonyl groups, s-butoxycarbonyl groups, t-butoxycarbonyl groups corresponding to alcohol alkyl esters. It may be a linear or branched C _1-12 alkoxycarbonyl group such as a group, a pentyloxycarbonyl group, a hexyloxycarbonyl group, or an octyloxycarbonyl group. The alkoxycarbonyl group may be a linear or branched C _1-10 alkoxycarbonyl group, preferably a C _1-6 alkoxycarbonyl group, more preferably a C _1-4 alkoxycarbonyl group. When a free carboxyl group (terminal carboxyl group) is converted to an alkyl ester, the thermal stability can be improved, the compatibility with the resin can be improved, and a high plasticizing effect can be obtained. Furthermore, since it is an oligomer, the melt fluidity of the resin composition can be improved, the moldability can be improved, and when a free carboxyl group is alkylesterified, the melt fluidity and moldability can be further improved with high thermal stability. It seems.

  In addition, it is not necessary that all the free carboxyl groups of the oligomer are esterified, and the ratio of the alkoxycarbonyl group to the entire carboxyl group and alkoxycarbonyl group is, for example, 10 to 100 mol% (for example, 30 to 99). Mol%), preferably 50 to 100 mol% (for example, 60 to 97 mol%), more preferably about 75 to 100 mol% (for example, 80 to 95 mol%).

  In addition, you may seal or protect the free hydroxyl group which remain | survives in an oligomer (single or copolymerization oligomer) with a conventional terminal blocker as needed. For example, the free hydroxyl group may be sealed with a carboxylic acid or acid halide, or may be sealed with a trialkylsilyl group or the like.

  Since such a plasticizer is in the form of an oligomer having a low molecular weight, it has a large plasticizing effect on the resin and can effectively improve the melt fluidity of the resin. Further, since at least 3-hydroxyalkanoic acid is used as a monomer and the main skeleton is an aliphatic skeleton, not only high biodegradability but also high biodegradability can be imparted to a predetermined resin. .

  The 3-hydroxyalkanoic acid and its lower alkyl ester as a monomer have low thermal stability and are not suitable for melt-kneading with a resin, but are made into a polymer (or oligomerized) as a plasticizer. The thermal stability of can be improved. The molecular weight of the biodegradable plasticizer may be relatively high as a number average molecular weight Mn of about 7000 to 10,000 in terms of polystyrene when measured by gel permeation chromatography (GPC). Usually, the number average molecular weight Mn is 180 to 3000. Low molecular weight of the order, for example, 180-2500 (for example, 250-2000), preferably 300-1500 (for example, 400-1200), more preferably 500-1000 (for example, 600-1000), usually 500-1500. It may be about (for example, 700 to 1000). The weight average molecular weight Mw can be selected from the range of about 200 to 10,000, for example, 300 to 9000 (for example, 500 to 8000), preferably 600 to 7500 (for example, 700 to 5000), and more preferably 800 to 3000 (for example, , 900-2000). Further, the molecular weight distribution (dispersion degree) Mw / Mn is, for example, 1 to 5 (for example, 1 to 3.5), preferably 1.1 to 3 (for example, 1.2 to 2.5), more preferably It may be about 1.2 to 2 (for example, 1.3 to 1.7).

  In addition, the oligomer (single or copolymerized oligomer) corresponds to the degree of polymerization (average polymerization degree), for example, 2 to 50 mer of the monomer (for example, 3-hydroxybutanoic acid) (for example, 2 To 40-mer), preferably 2 to 30-mer (for example, 3 to 20-mer), more preferably 3 to 15-mer (for example, 4 to 12-mer). It may be an oligomer of about the body (for example, 4-7 mer). It seems that the plasticity and thermal stability of the resin can be controlled by adjusting the molecular weight of the biodegradable plasticizer.

  It should be noted that 3-hydroxyalkanoic acid (such as 3-hydroxybutyric acid (3HB)) in which the 2-position adjacent to the carboxyl group is a methylene group and the hydroxyl group is a secondary hydroxyl group is a polymer having a high molecular weight due to microorganisms in nature. However, when it is artificially esterified and polymerized, a dehydration reaction occurs along with the esterification reaction, and a monofunctional unsaturated monocarboxylic acid such as crotonic acid is easily generated. Therefore, when such 3-hydroxyalkanoic acid is used, it is usually difficult to produce a high molecular weight polymer, and a low molecular weight polyester (for example, oligo (3-hydroxyalkanoate) in an oligomer region or its Only alkyl esters). In the present invention, high plasticity and melt fluidity can be imparted by adding low molecular weight poly (3-hydroxyalkanoic acid) to a predetermined resin.

  The monomer (including the second monomer) and the oligomer may be optical isomers (R-form or S-form, particularly R-form), or a racemate.

  A preferred oligomer is a polymer using at least 3-hydroxybutyric acid (3HB), for example, (a) a homopolymer of 3-hydroxybutyric acid (3HB), (b) 3-hydroxybutyric acid (3HB) and the second A copolymer of 3-hydroxyalkanoic acid, and (c) a copolymer of 3-hydroxyalkanoic acid and the second monomer, wherein in the copolymer (c), the 3-hydroxyalkanoic acid The alkanoic acid may contain 3-hydroxybutyric acid (3HB) and the second 3-hydroxyalkanoic acid. The homopolymer or copolymer (a) (b) can be represented by, for example, the following formula (1), and the copolymer (c) can be represented by, for example, the following formula (2).

  When the oligomer represented by the following formulas (1) and (2) is a copolymer, the oligomer may be a block copolymer, but is often a random copolymer. That is, in the formulas (1) and (2), the coefficients m1, m2, m, and n simply indicate the quantitative ratio of each monomer, and are formed by monomer multimers (homopolymers). It does not indicate a block unit.

(Wherein R ¹ represents a hydrogen atom or an alkyl group, R ³ represents an alkyl group, m1 represents an integer of 1 or more, m2 represents an integer of 0 or more, and m1 + m2 represents an integer of 2 to 50)

(In the formula, R ² is a hydrogen atom or an alkyl group, p is 0 or an integer of 2 to 10, m is an integer of 1 or more, n is an integer of 1 or more, and (m1 + m2) + n is 2 to 50) And R ¹ , R ³ , m1 and m2 are the same as in formula (1))

Examples of the alkyl group represented by R ¹ include linear or branched C such as ethyl, propyl, isopropyl, butyl, s-butyl, t-butyl, hexyl, and octyl. _2-12 alkyl group, preferably linear or branched C _2-8 alkyl group, more preferably linear or branched C _2-6 alkyl group (for example, linear or branched C _{2 -4} alkyl group). The group R ¹ is often a hydrogen atom or a linear C _2-6 alkyl group (preferably a C _2-4 alkyl group).

The alkyl group represented by R ³ corresponds to an alkoxycarbonyl group formed by alkyl esterification of a free carboxyl group. For example, a methyl group, an ethyl group, a propyl group, an i-propyl group, a butyl group, an i- Linear or branched C _1-10 alkyl group such as butyl group, s-butyl group, t-butyl group, pentyl group, hexyl group, octyl group, etc., preferably linear or branched C _1-6 It may be an alkyl group.

  In the formulas (1) and (2), the ratio between m1 and m2 corresponds to the ratio between 3-hydroxybutanoic acid and the second 3-hydroxyalkanoic acid, and m1 / m2 = 0.5 / 0.5 to 1/0 (for example, 0.75 / 0.25 to 0.97 / 0.03), preferably 0.8 / 0.2 to 1/0 (for example, 0.85 / 0.15) About 0.95 / 0.05).

In the formula (2), examples of the alkyl group represented by R ² include the same C _1-12 alkyl group as R ¹ . R ² is often a hydrogen atom or a C _1-10 alkyl group (preferably a C _1-6 alkyl group, more preferably a C _1-4 alkyl group). p corresponds to the number of carbon atoms of the second hydroxycarboxylic acid (second monomer) together with R ² , and is 0, or an integer of 2 to 10 (eg, 2 to 8), preferably 0 or About 2-6 (for example, 2-4) may be sufficient.

  The ratio between m and n corresponds to the ratio (molar ratio) between the first hydroxycarboxylic acid (first monomer) and the second hydroxycarboxylic acid (second monomer), For example, m / n = 0.5 / 0.5 to 0.99 / 0.01 (for example, 0.75 / 0.25 to 0.98 / 0.02, preferably 0.8 / 0.2 to 0.95 / 0.05).

  In the formulas (1) and (2), m1 + m2 and (m1 + m2) + n correspond to the molecular weight (number average molecular weight) and the degree of polymerization, for example, 2 to 50 (for example, 2 to 40), preferably 2 -30 (for example, 3-25), More preferably, 3-20 (for example, 4-15) may be sufficient, and about 3-10 (for example, 4-6) may be sufficient.

  Such oligomers may be prepared using microbial productivity or enzymatic reactions and, if necessary, prepared by degrading high molecular weight poly (hydroxyalkanoate) using acid or base. However, it is usually prepared by a chemical polyesterification method, for example, by subjecting a monomer containing at least 3-hydroxyalkanoic acid or an alkyl ester thereof to an esterification reaction (or transesterification reaction) by a conventional method. it can. The reaction may be carried out in the presence or absence of a catalyst. Examples of the catalyst include metal catalysts [eg, alkali metals (such as sodium), alkaline earth metals (such as magnesium, calcium, barium), transition metals] (Manganese, zinc, lead, cobalt, titanium, etc.), periodic table group 13 metals (aluminum, etc.), periodic table group 14 metals (germanium, tin, etc.), periodic table group 15 metals (antimony, etc.), etc. Metal compounds, etc.], base catalysts (eg, tertiary amines (trialkylamines such as trimethylamine and triethylamine, quaternary ammonium salts (tetraalkylammonium halides such as tetraethylammonium chloride and tetraethylammonium bromide, benzyltrimethyl chloride) Benzyltrialkyl amines such as ammonium ), Acid catalysts [eg, inorganic acids (eg, sulfuric acid, hydrogen chloride (or hydrochloric acid), nitric acid, phosphoric acid, etc.), organic acids (eg, sulfonic acid (methanesulfonic acid, ethanesulfonic acid, trifluoro) Alkanesulfonic acid such as romethanesulfonic acid, arenesulfonic acid such as p-toluenesulfonic acid) etc.) etc. Examples of metal compounds include organic acid salts (acetates, propionates, etc.), inorganic Acid salts (borate, carbonate, etc.), metal oxides (germanium oxide, etc.), metal chlorides (tin chloride, etc.), metal alkoxides (titanium tetraalkoxide (titanium tetraisopropoxide, titanium tetra-t-butoxide, etc.)) Aluminum isopropoxide, zinc t-butoxide, potassium t-butoxide, etc.), alkyl Such as a metal (trialkyl aluminum) may be exemplified. These catalysts may be used singly or two or more.

  The amount of the catalyst used is, for example, about 0.001 to 1 mol, preferably 0.005 to 0.5 mol, and more preferably about 0.01 to 0.1 mol with respect to 100 mol of all monomers. Also good.

As the polymerization method, a conventional method such as a melt polymerization method, a solution polymerization method, and an interfacial polymerization method can be used. The reaction may be performed in the presence or absence of a solvent depending on the polymerization method. Examples of the solvent include hydrocarbons (aliphatic hydrocarbons such as hexane, octane and cyclohexane, aromatic hydrocarbons such as toluene), halogenated hydrocarbons (dichloromethane, chloroform, carbon tetrachloride, etc.), ether (Cyclic ethers such as dioxane and tetrahydrofuran), ketones (acetone, methyl ethyl ketone, etc.), esters (methyl acetate, ethyl acetate, butyl acetate, etc.), amides (dimethylformamide, diethylformamide, dimethylacetamide, diethylacetamide, etc.) ), Sulfoxides (such as dimethyl sulfoxide), cellosolve acetates (such as _C1-4 alkyl cellosolve acetate such as ethyl cellosolve acetate), and the like. These solvents can be used alone or in combination of two or more.

  The reaction can usually be performed in an inert gas (nitrogen, helium, etc.) atmosphere. Further, the reaction may be carried out at room temperature or under reduced pressure, or may be carried out while distilling produced water or the like out of the reaction system.

  The reaction temperature may be, for example, about 50 to 200 ° C, preferably 70 to 180 ° C, more preferably about 100 to 150 ° C. The reaction time is not particularly limited, and may be, for example, 30 minutes to 48 hours, usually about 1 to 36 hours.

  In addition, when using alkyl ester (3-hydroxy alkanoic acid alkyl ester etc.) as a monomer, it is not necessarily required, but the oligomer which has a free carboxyl group, for example, 3 which has a free carboxyl group as a monomer -In the oligomer prepared using hydroxyalkanoic acid, the free carboxyl group of the produced oligomer may be esterified with alcohol. Moreover, the alkoxycarbonyl group of the oligomer produced | generated by the said reaction is the alkoxycarbonyl group of carbon number or structure different from the alkoxycarbonyl group of an oligomer by esterification and / or transesterification with other alcohol if necessary. May be converted to The esterification reaction can be performed by reacting with an alcohol in the same manner as the esterification reaction. The transesterification reaction can also be performed using a conventional method, for example, an acid catalyst or a base catalyst.

  Moreover, after completion | finish of reaction, you may isolate | separate and refine a single or copolymerization oligomer by the conventional separation method, for example, the method of reprecipitating a reaction product with a poor solvent.

  The biodegradable plasticizer may be formed of an oligomer containing the 3-hydroxyalkanoic acid as a constituent unit, and if necessary, an additive such as a plasticizer (for example, a plasticizer that may be biodegradable) (For example, plasticizers having an ester bond such as adipic acid ester, sebacic acid ester, alkanediol diaryl ester, phthalic acid ester, aliphatic polyester plasticizer) and the like. The proportion of the biodegradable plasticizer may be 50% by weight or more (for example, 70 to 100% by weight) with respect to the entire plasticizer.

[Resin composition (or biodegradable resin composition)]
As long as the resin needs to be plasticized, the resin may be a thermosetting resin or a thermoplastic resin, and is a resin that is difficult to be decomposed by microorganisms (a resin having poor biodegradability). Also good. Furthermore, the resin may be a hard and / or brittle resin. The resin is often a thermoplastic resin, and may have at least an ester bond or an amide bond as a linking group in order to improve biodegradability. Examples of such a resin include a polyester resin, a polyamide resin, a polyesteramide resin, a polyester carbonate resin, and a polycarbonate resin. These resins can be used alone or in combination of two or more. Of these resins, usually, a resin having at least an ester bond as a linking group is often used.

  The polyester resin can be prepared by a reaction of a dicarboxylic acid component and a diol component, a reaction of a hydroxycarboxylic acid component (or a lactone component equivalent to hydroxycarboxylic acid), or a reaction of a dicarboxylic acid component, a diol component, and a hydroxycarboxylic acid component.

(Dicarboxylic acid component)
Examples of the dicarboxylic acid component include aliphatic dicarboxylic acid, alicyclic dicarboxylic acid, and aromatic dicarboxylic acid. Examples of the aliphatic dicarboxylic acid include alkane dicarboxylic acids (for example, C _2-16 alkane diacids such as malonic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, decanedicarboxylic acid, and dodecanedioic acid. -Carboxylic acid etc.), unsaturated aliphatic dicarboxylic acid (for example, _C4-10 alkene-dicarboxylic acid such as maleic acid, fumaric acid, itaconic acid, etc.) and the like.

Examples of the alicyclic dicarboxylic acid include cycloalkane dicarboxylic acid (eg, C _5-10 cycloalkane-dicarboxylic acid such as 1,4-cyclohexanedicarboxylic acid), di- or tricycloalkane dicarboxylic acid (eg, decalin dicarboxylic acid). Acid, norbornane dicarboxylic acid, adamantane dicarboxylic acid, tricyclodecane dicarboxylic acid, etc.), cycloalkene dicarboxylic acid (eg, C _5-10 cycloalkene-dicarboxylic acid such as cyclohexene dicarboxylic acid), di- or tricycloalkene dicarboxylic acid (eg, And norbornene dicarboxylic acid).

Examples of the aromatic dicarboxylic acid include monocyclic aromatic dicarboxylic acids [for example, C _1-4 alkyl-isophthalic acid such as phthalic acid, terephthalic acid, isophthalic acid, alkylisophthalic acid (for example, 4-methylisophthalic acid, etc.) C _6-10 arene-dicarboxylic acid and the like], polycyclic aromatic dicarboxylic acid [for example, condensed polycyclic aromatic dicarboxylic acid [for example, naphthalenedicarboxylic acid (for example, 1,4-naphthalenedicarboxylic acid, 1 , 5-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 1,7-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, naphthalenedicarboxylic acid such as 2,6-naphthalenedicarboxylic acid), anthracenedicarboxylic acid, phenanthrene fused polycyclic _{C 10-24} arene such as dicarboxylic acid - Carboxylic acids, preferably fused polycyclic _{C 10-16} arene - dicarboxylic acid, more preferably fused polycyclic _{C 10-14} arene - such as dicarboxylic acids, aryl array Nji carboxylic acid [e.g., biphenyl dicarboxylic acids (e.g., 2 , 2'-biphenyl dicarboxylic acid, 4,4'-biphenyl and di-carboxylic acids) _{C 6-10} aryl _{-C 6-10} arene such as - such as dicarboxylic acids, diaryl alkane dicarboxylic acid [for example, diphenyl alkane dicarboxylic acids (e.g. DiC _6-10 aryl C _1-6 alkane-dicarboxylic acid etc.] such as 4,4′-diphenylmethane dicarboxylic acid etc.], diaryl ketone dicarboxylic acid [eg diphenyl ketone dicarboxylic acid (eg 4.4′-diphenyl etc.) di-C, such as ketones such as dicarboxylic acid) _{6- 10} aryl ketone-dicarboxylic acid)], dicarboxylic acid having a fluorene skeleton, etc.].

Examples of the dicarboxylic acid having a fluorene skeleton include dicarboxyfluorene (eg, 2,7-dicarboxyfluorene); 9,9-bis (carboxyalkyl) fluorene [eg, 9,9-bis (2-carboxyl). Ethyl) fluorene, 9,9-bis (carboxy C _2-6 alkyl) fluorene, such as 9,9-bis (2-carboxypropyl) fluorene, etc.]; 9- (carboxy-carboxyalkyl) fluorene [eg, 9- ( 1-carboxy-2-carboxyethyl) fluorene, 9- (carboxy-carboxy C _2-6 alkyl) fluorene such as 9- (2-carboxy-3-carboxypropyl) fluorene, etc.]; 9,9-bis (carboxyaryl) Fluorene [e.g., 9,9-bis (3-carboxyl Enyl) fluorene, 9,9-bis (4-carboxyphenyl) fluorene, 9,9-bis (5-carboxy-1-naphthyl) fluorene, 9,9-bis (6-carboxy-2-naphthyl) fluorene, etc. 9,9-bis (carboxyC _6-12 aryl) fluorene and the like]; 9,9-bis (carboxyalkyl-aryl) fluorene [eg, 9,9-bis (4- (carboxymethyl) phenyl) fluorene, 9-bis (4- (2-carboxyethyl) phenyl) fluorene, 9,9-bis (3- (carboxymethyl) phenyl) fluorene, 9,9-bis (5- (carboxymethyl) -1-naphthyl) fluorene , 9,9-bis (6- (carboxymethyl) -2-naphthyl) fluorene such as 9,9-bis (carboxy _{C 1-6} Alkyl _{-C 6-12} aryl) fluorene], and others.

These dicarboxylic acids can be used alone or in combination of two or more. These dicarboxylic acids can be selected according to the use, and may be an aliphatic dicarboxylic acid (C _2-6 alkane-dicarboxylic acid such as succinic acid and adipic acid) from the viewpoint that biodegradability can be improved. An aromatic dicarboxylic acid unit (for example, a dicarboxylic acid having a fluorene skeleton) may be used from the viewpoint of improving heat resistance and the like.

(Diol component)
Examples of the diol component include aliphatic diols, alicyclic diols, and aromatic diols. Examples of the aliphatic diol include alkane diols (for example, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol. , 1,3-pentanediol, 1,4-pentanediol, 1,5-pentanediol, C _2-10 alkanediol such as neopentylglycol, etc.), polyalkanediol (for example, diethylene glycol, dipropylene glycol, triethylene And di- or tri-C _2-4 alkanediol such as glycol).

Examples of the alicyclic diol include cycloalkanediol (for example, C _5-8 cycloalkanediol such as cyclohexanediol) and di (hydroxyalkyl) cycloalkane (for example, di (hydroxyC _1-4 ) such as cyclohexanedimethanol. Alkyl) C _5-8 cycloalkane, etc.), isosorbide and the like.

Examples of the aromatic diol include dihydroxyarenes (for example, hydroquinone and resorcinol) and di (hydroxyalkyl) arenes (for example, di (hydroxyC ₁ ) such as 1,3-benzenedimethanol and 1,4-benzenedimethanol. _-4 alkyl) C _6-10 arene), bisphenols (eg, bis (hydroxyphenyl) C _1-10 alkanes such as biphenol and bisphenol A), alkylene oxide adducts of bisphenols, diols having a fluorene skeleton, etc. Is mentioned.

  Examples of the diol having a fluorene skeleton include diol compounds having a 9,9-bis (hydroxyaryl) fluorene skeleton, for example, a diol represented by the following formula (3).

(In the formula, ring Z is an arene ring, R ⁵ is an alkylene group, R ⁶ and R ⁷ are substituents, q is 0 or an integer of 1 or more, r is 0 or an integer of 1 or more, and s is 0 to 4) Is an integer).

In the formula (3), examples of the arene ring represented by the ring Z include a monocyclic arene ring such as a benzene ring, a polycyclic arene ring, and the like. The polycyclic arene ring includes a condensed polycyclic arene. ring [e.g., fused bicyclic arene (e.g., fused bicyclic C _10-16 arene such as naphthalene ring), such as fused bicyclic or tetracyclic arene ring such as ring, ring assembly arene ring [Biaren ring (e.g., BiC _6-12 arene rings such as biphenyl ring and binaphthyl ring] and the like. The two rings Z may be the same or different rings. Preferred arene rings include benzene ring, naphthalene ring, biphenyl ring and the like.

In the formula (3), examples of the alkylene group R ⁵ include C _2-6 alkylene groups such as an ethylene group, a propylene group, a trimethylene group, and a 1,2-butanediyl group.

The number r of oxyalkylene groups (OR ⁵ ) can be selected, for example, from a range of about an integer of 0 to 15 (eg, an integer of 0 to 10), for example, an integer of 0 to 8 (eg, 1 to 8), Preferably, it may be an integer of 0 to 4 (for example, 1 to 4), particularly an integer of about 0 to 3 (for example, 1 to 3), and is usually an integer of 0 to 2 (for example, 0 or 1). There may be. Note that when r is an integer of 2 or more types of alkylene groups R ⁵ may be the same or different. Further, the type of alkylene group R ⁵ may be the same or different in the same or different ring Z.

The group [HO— (R ⁵ O) _r —] can be substituted at an appropriate position of the ring Z. For example, when the ring Z is a benzene ring, the 2-4 position (especially 3- In many cases, when ring Z is a naphthalene ring, it is often substituted at the 5- to 8-position of the naphthyl group, for example, the 9-position of fluorene. Is substituted at the 1-position or 2-position of the naphthalene ring (substitution is made in relation to 1-naphthyl or 2-naphthyl), and the 1,5-position, 2,6-position, etc. with respect to this substitution position In many cases, the group [HO— (R ⁵ O) _r —] is substituted. In the ring assembly arene ring Z, the substitution position of the group [HO— (R ⁵ O) _r —] is not particularly limited. For example, the arene ring bonded to the 9-position of fluorene and / or this arene ring It may be substituted on the adjacent arene ring. For example, the 3-position or 4-position of the biphenyl ring Z may be bonded to the 9-position of fluorene, and when the 3-position of the biphenyl ring Z is bonded to the 9-position of fluorene, the group [HO The substitution position of — (R ⁵ O) _r —] may be any of 2-, 4-6-position and 2′-6′-position of biphenyl ring Z, and usually 4-, 5-, It may be substituted at the 6-position, 3′-, 4′-position, preferably 4-, 6-position, 4′-position (particularly the 6-position).

In the formula (3), examples of the substituent R ⁶ include an alkyl group (eg, a C _1-6 alkyl group such as a methyl group, an ethyl group, and a propyl group), a cycloalkyl group (such as a cyclohexyl group), and the like. C _5-8 cycloalkyl group, etc.), aryl groups (eg, C _6-10 aryl groups such as phenyl group, tolyl group, xylyl group, naphthyl group, etc.), aralkyl groups (C _6-6 such as benzyl group, phenethyl group, etc.). ₁₀ an aryl _{-C 1-4} alkyl group) carbon atoms and the like; alkoxy group (methoxy group, a _{C 1-6} alkoxy group such as ethoxy group), _C of such cycloalkyl group (hexyloxy group cycloheteroalkyl _{5- 8} such cycloalkyloxy group), _{C 6-10} aryloxy groups such as an aryloxy group (phenoxy group), aralkyloxy group (benzyl Such as _{C 1-8} alkylthio group such as an alkylthio group (methylthio group);; _{C 6-10} aryl _{-C 1-4} alkyl group), such as oxy _{C 1-6} alkyl, such as acyl groups (acetyl group - carbonyl group Alkyloxycarbonyl group (C _1-4 alkyloxy-carbonyl group such as methoxycarbonyl group); halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom etc.); nitro group; cyano group; dialkylamino group (e.g., di-C _1-4 alkylamino group such as dimethylamino group); dialkyl carbonyl amino group (e.g., di (C _1-4 alkyl such as diacetylamino groups - carbonyl) amino group, etc.), and others .

Representative substituents R ⁶ include C _1-6 alkyl groups (particularly methyl groups), C _6-10 aryl groups (particularly phenyl groups), C _6-8 aryl-C _1-2 alkyl groups, C _{1- 4} alkoxy group etc. are mentioned. In addition, when the substituent R ⁶ is an aryl group, the substituent R ⁶ may form the ring assembly arene ring together with the ring Z. The type of the substituent R ⁶ may be the same or different in the same or different ring Z.

The number of substitution q can be appropriately selected according to the type of ring Z and the like, and may be an integer of about 0 to 8, for example, an integer of 0 to 4, preferably an integer of 0 to 3 (for example, 0 to 2), In particular, it may be 0 or 1. In particular, when q is 1, the ring Z may be a benzene ring, a naphthalene ring or a biphenyl ring, and the substituent R ⁶ may be a methyl group.

Examples of the substituent R ⁷ include a cyano group, a halogen atom (fluorine atom, chlorine atom, bromine atom, etc.), an alkyl group (C _1-6 alkyl group such as methyl group, ethyl group, propyl group), an aryl group ( C _6-10 aryl group such as phenyl group). The substituent R ⁷ is often an alkyl group (for example, a C _1-4 alkyl group, particularly a C _1-3 alkyl group such as a methyl group). The substitution number s is an integer of 0 to 4 (for example, 0 to 3), preferably an integer of 0 to 2 (for example, 0 or 1), particularly 0. The number of substitutions s may be the same or different from each other. When s is 2 or more, the types of the substituents R ⁷ may be the same or different from each other, and are substituted with two benzene rings of the fluorene ring. The type of the substituent R ⁷ may be the same or different. Further, the substitution position of the substituent R ⁷ is not particularly limited, and may be, for example, 2-position to 7-position (2-position, 3-position and / or 7-position, etc.) of the fluorene ring.

In the formula (3), examples of the compound in which r is 0 include 9,9-bis (hydroxyaryl) fluorenes such as 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis (3 9,9-bis (hydroxyC _6-12 ) such as -hydroxyphenyl) fluorene, 9,9-bis (6-hydroxy-2-naphthyl) fluorene, 9,9-bis (5-hydroxy-1-naphthyl) fluorene Aryl) fluorene; 9,9-bis (C _6-12 aryl) such as 9,9-bis (3-phenyl-4-hydroxyphenyl) fluorene, 9,9-bis (4-phenyl-3-hydroxyphenyl) fluorene - hydroxy _{C 6-12} aryl) fluorene; 9,9-bis (3-methyl-4-hydroxyphenyl) fluorene, 9,9-bis (4 Methyl-3-hydroxyphenyl) fluorene such as 9,9-bis _{(C 1-4} alkyl - hydroxy _{C 6-12} aryl) fluorene, and others.

In the formula (3), examples of the compound in which r is 1 include 9,9-bis (hydroxyalkoxyaryl) fluorenes such as 9,9-bis [4- (2-hydroxyethoxy) phenyl] fluorene, 9 , 9-bis [4- (2-hydroxypropoxy) phenyl] fluorene, 9,9-bis [6- (2-hydroxyethoxy) -2-naphthyl] fluorene, 9,9-bis [5- (2-hydroxy) propoxy) -1-naphthyl] fluorene such as 9,9-bis (hydroxy _{C 2-4} alkoxy _{C 6-12} aryl) fluorene; 9,9-bis [4-phenyl-3- (2-hydroxyethoxy) phenyl] fluorene, 9,9-bis [3-phenyl-4- (2-hydroxypropoxy) phenyl] fluorene such as 9,9-bis _{[C 6-12} Reel - hydroxy _{C 2-4} alkoxy _{C 6-12} aryl] fluorene; 9,9-bis [3-methyl-4- (2-hydroxyethoxy) phenyl] fluorene, 9,9-bis [4-methyl-3- Examples include 9,9-bis [C _1-4 alkyl-hydroxy C _2-4 alkoxy C _6-12 aryl] fluorene such as (2-hydroxypropoxy) phenyl] fluorene.

In the above formula (3), the compound in which r is 2 or more corresponds to the compound in which r is 0 or 1, and the repeating unit r of the oxyalkylene group (especially oxyC _2-4 alkylene group) is 2 to 5. Compound etc. are mentioned.

These diol components can be used alone or in combination of two or more. These diol components can be selected according to the use and can improve biodegradability. From the viewpoint of improving the biodegradability, aliphatic diols [for example, C _2-6 alkanediols such as ethylene glycol and 1,4-butanediol (especially C _{2− 4} alkanediol), etc.], or an aromatic diol unit (for example, a diol having a fluorene skeleton) from the viewpoint of improving heat resistance and the like.

  Examples of the hydroxycarboxylic acid component include hydroxyalkanoic acids (for example, the above-mentioned 3-hydroxyalkanoic acid (first and second 3-hydroxyalkanoic acid), second hydroxycarboxylic acid (second monomer)), and the like Examples thereof include lactone components, acid halides or lower alkyl esters equivalent to the hydroxyalkanoic acid.

The polyester resin is an aliphatic polyester resin (hydroxyalkanoic acid homopolymer or copolymer (polyhydroxyalkanoate PHA), for example, polylactic acid (PLA), homopolymer of hydroxyalkanoic acid such as polyhydroxybutyric acid (PHB), Poly (lactic acid-co-3-hydroxybutyric acid), poly (3-hydroxybutyric acid-co-3-hydroxyvaleric acid), poly (3-hydroxybutyric acid-co-3-hydroxyhexanoic acid), poly (3-hydroxybutyric acid) -Co-4-hydroxybutyric acid) and other hydroxyalkanoic acids (for example, copolymers of 3-hydroxyalkanoic acid); alkanedicarboxylic acid, alkylene glycol, and / or hydroxyalkanoic acid at least as a monomer (reaction component) Polymers (polybutylene succinate (PBS), polybutylene Succinate adipate (PBSA), polybutylene adipate terephthalate (PBAT), polycaprolactone (PCL), polyethylene adipate, poly _{C 2-6} alkylene _{C 3-12} alkanoate, such as polyethylene sebacate)), alicyclic polyester resin (polyethylene Poly C _2-6 alkylene C _6-12 cycloalkanoate such as cyclohexanoate), aromatic polyester resin (polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polytrimethylene naphthalate, polytetramethylene naphthalate) Poly C _2-6 alkylene C _6-12 arylate (homopolyester) such as phthalate, Al containing C _2-6 alkylene C _6-12 arylate units Xylene arylate copolymers (copolyesters) (for example, copolyesters obtained by copolymerizing aliphatic dicarboxylic acids such as adipic acid, and asymmetric aromatic dicarboxylic acids such as isophthalic acid and phthalic acid), 9,9-bisarylfluorene Examples thereof include polyester resins containing units). Examples of the polyester resin containing a 9,9-bisarylfluorene unit include compounds represented by the above formula (3) (for example, 9,9-bis [4- (2-hydroxyethoxy) phenyl] fluorene) and alkylene glycol. Examples include polymers of (for example, ethylene glycol), cycloalkane dicarboxylic acids (for example, cyclohexane dicarboxylic acid) and / or arene dicarboxylic acids (for example, terephthalic acid, isophthalic acid, etc.), and alkane dicarboxylic acids as necessary. it can.

  The polyamide resin can be prepared by a reaction of a dicarboxylic acid component and a diamine component, a reaction of an aminocarboxylic acid component or a lactam component thereof, or a reaction of a dicarboxylic acid component, a diamine component, an aminocarboxylic acid component and / or a lactam component thereof.

Examples of the dicarboxylic acid component include the same dicarboxylic acid as the dicarboxylic acid component described in the section of the polyester resin. A preferred dicarboxylic acid component may be an aliphatic dicarboxylic acid (alkane dicarboxylic acid), for example, a C _2-16 alkane dicarboxylic acid such as adipic acid (eg, C _4-10 alkane-dicarboxylic acid).

Examples of the diamine component include aliphatic diamines (eg, linear or branched C _2-16 alkylene diamines such as ethylene diamine, propylene diamine, tetramethylene diamine, hexamethylene diamine, and trimethyl hexamethylene diamine (eg, linear Or branched C _2-10 alkylene diamine), linear or branched poly C _2-10 alkylene polyamine such as diethylenetriamine, triethylenetetramine, dipropylene diamine), alicyclic diamine (eg, isophorone diamine, Bis (aminomethyl) cyclohexane, mensendiamine, bis (4-amino-3-methylcyclohexyl) methane, etc.), aromatic diamines (eg, phenylenediamine, bis (4-aminodiphenyl) methane, bis (4-amino) Eniru) sulfone, bis (4-amino-3-ethylphenyl) methane, etc.), aromatic aliphatic diamines (such as xylylenediamine), and others. These diamine components can be used alone or in combination of two or more.

Examples of the lactam component include C _4-12 lactams such as γ-valerolactam, δ-valerolactam, ε-caprolactam, and ω-laurolactam. Examples of the aminocarboxylic acid component include aminoundecanoic acid, Examples thereof include amino C _4-12 alkanoic acids such as aminododecanoic acid and aminoarene carboxylic acids such as aminobenzoic acid. These lactam components and aminocarboxylic acid components can also be used alone or in combination of two or more.

  Polyamide resins include aliphatic polyamide resins (polyamide 6, polyamide 66, polyamide 610, polyamide 11, polyamide 12, polyamide 612, etc.), alicyclic polyamide resins (polymers of bis (aminomethyl) cyclohexane and adipic acid, etc.) , Aromatic polyamides (polyamide MXD (polymer of xylylenediamine and adipic acid), polymers of trimethylhexamethylenediamine and terephthalic acid, etc.), copolyamides (copolyamides in which homopolyamide components are copolymerized, such as , Copolyamide 6/66, copolyamide 6/11, copolyamide 66/12, etc.). The polyamide resin may be a polyamide having an N-alkoxymethyl group, a polymerized fatty acid-based polyamide resin containing dimer acid which is a dimer of unsaturated higher fatty acid as a polymerization component, and the like. The polyamide resin may be crystalline or amorphous, or may be a transparent polyamide resin (amorphous transparent polyamide resin). These polyamide resins can be used alone or in combination of two or more. The polyamide resin is usually often an aliphatic homo or copolyamide resin.

  The polyesteramide resin is a method of using a diamine component as a part of a diol component, a part of a dicarboxylic acid component and a diol component, or a hydroxycarboxylic acid (or hydroxyalkanoic acid) component and / or a lactone component in the preparation of the polyester resin. It can be prepared by introducing an amide bond into the polymer main chain by a method using a lactam component and / or an aminocarboxylic acid component as at least a part of the polymer.

  Examples of the diamine component, lactam component, and aminocarboxylic acid component include the same diamine, lactam component, and aminocarboxylic acid as those described in the section of the polyamide resin.

  The polycarbonate resin can be prepared by reacting the diol component exemplified in the section of the polyester resin with diphenyl carbonate or phosgene. For example, a bisphenol type polycarbonate (a polycarbonate such as bisphenol A type, F type, S type, or AD type). ) And copolycarbonate. The polyester carbonate resin can be prepared by using the dicarboxylic acid component exemplified in the section of the polyester resin in the preparation of the polycarbonate resin.

These resins may be curable resins (for example, unsaturated polyester resins having maleic anhydride, fumaric acid, itaconic acid and the like as C _2-10 alkene-dicarboxylic acids and the like as dicarboxylic acid components). A thermoplastic resin is preferred from the viewpoint of excellent biodegradability.

These resins can be used alone or in combination of two or more. Of these resins, a resin having at least an ester bond is often used, and a biodegradable resin such as polylactic acid (PLA), a high molecular weight oligomer represented by the above formulas (1) and (2), For example, hydroxyalkanoic acid alone or in combination such as polyhydroxybutyric acid (PHB), poly (3-hydroxybutyric acid-co-3-hydroxyvaleric acid), poly (3-hydroxybutyric acid-co-3-hydroxyhexanoic acid) Combined (polyhydroxyalkanoate: PHA); Poly C _2-4 alkylene C _3-10 alkanoate such as PBS, PBSA, PBAT, PCL, polyethylene adipate; In these polyesters, C _2-4 alkylene C ₆ as copolymerized units Copolyesters containing _-10 arylate units are often used. In many cases, a polyesteramide resin, a polyester carbonate resin, or the like corresponding to the reester resin is used.

In addition, the molecular weight of the resin (for example, the high molecular weight oligomer represented by the formulas (1) and (2)) is higher than that of the oligomer (or plasticizer), and is measured in terms of polystyrene when measured by GPC. The number average molecular weight Mn is, for example, 0.7 × 10 ^{4 to} 300 × 10 ⁴ (for example, 0.8 × 10 ⁴ to 200 × 10 ⁴ ), preferably 1 × 10 ^{4 to} 100 × 10 ⁴ (for example, 1.5 × 10 ⁴ to 70 × 10 ⁴ ), more preferably about 2 × 10 ⁴ to 50 × 10 ⁴ (for example, 5 × 10 ⁴ to 30 × 10 ⁴ ). The weight average molecular weight Mw is, for example, 1 × 10 ^{4 to} 500 × 10 ⁴ (for example, 2 × 10 ^{4 to} 300 × 10 ⁴ ), preferably 3 × 10 ⁴ to 200 × 10 ⁴ (for example, 5 × 10 ⁴ to It may be about 100 × 10 ⁴ ). Further, the molecular weight distribution (dispersion degree) Mw / Mn is, for example, 1 to 5 (for example, 1 to 3.5), preferably 1.1 to 3 (for example, 1.2 to 2.5), more preferably It may be about 1.2 to 2 (for example, 1.3 to 1.7).

  The resin composition (or biodegradable resin composition) of the present invention contains the resin and a plasticizer (or biodegradable plasticizer), and a plasticizer is added in a small proportion to the resin. As a result, the plasticity of the resin can be greatly improved. Furthermore, the melt fluidity can also be improved. Therefore, the mechanical properties of the resin can be easily adjusted and the moldability can be improved. Furthermore, the biodegradability of the resin can be improved or improved by the plasticizer.

  In particular, some of the resins (particularly biodegradable resins) have biodegradability, but have poor mechanical properties and moldability. For example, a homo- or copolymer of 3-hydroxyalkanoic acid such as polyhydroxybutyric acid (PHB) is excellent in biodegradability (particularly anaerobic degradability), but may be hard and brittle. The plasticizer of the present invention is extremely useful for plasticizing a biodegradable resin because it is highly compatible with such a resin without impairing biodegradability. Furthermore, it is useful for improving melt flowability and improving melt moldability (injection moldability, extrusion moldability, etc.) without significantly degrading thermal properties.

  The proportion of the plasticizer (or biodegradable plasticizer) is 0.1 to 50 parts by weight (eg 0.5 to 40 parts by weight), preferably 1 to 30 parts by weight (eg 2 to 25 parts by weight), more preferably about 3 to 20 parts by weight (for example, 3 to 15 parts by weight), or about 2 to 10 parts by weight (for example, 3 to 7 parts by weight). Good. If the amount of the biodegradable plasticizer used is too small, the degree of plasticization of the resin is lowered, and if it is too much, the mechanical properties of the resin may be lowered.

  In addition, even if a biodegradable component (for example, biodegradable plasticizer, biodegradable resin) is added to a non-biodegradable resin that is not decomposed by microorganisms, the non-biodegradable resin is not decomposed, Only biodegradable components are expected to undergo preferential microbial degradation and degradation. However, when the plasticizer of the present invention is added, it can be decomposed significantly even in a resin having poor biodegradability, and even under anaerobic conditions. Therefore, not only the composting process under aerobic conditions but also biodegradability in the ocean can be improved, and there is a possibility that the problem of microplastic, which has become a new problem in recent years, can be solved. In addition, a molded body such as a garbage bag formed of a resin to which a biodegradable plasticizer is added can be directly biogasified.

  The resin composition (or biodegradable resin composition) is optionally added with various additives, such as stabilizers (antioxidants, heat stabilizers, light stabilizers, etc.), surfactants, lubricants, colorants, A filler, an antistatic agent, a silane coupling agent, a dispersant, a dispersion aid, a mold release agent, and the like may be included, and a plasticizer different from the biodegradable plasticizer may be included. An additive can be used individually or in combination of 2 or more types.

  The resin composition may be in the form of a mixture of a resin and a plasticizer, or may be in the form of granules or pellets in which the resin and the biodegradable plasticizer are kneaded and integrated. Resin compositions are three-dimensional, such as linear, film or sheet, cylindrical or pipe, casing, housing, etc., by conventional molding methods (extrusion molding, melt molding methods such as injection molding methods, casting methods, etc.) A molded body having a predetermined shape such as a shape can be produced.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples. In addition, the measuring method of a test item is as follows.

(Molecular weight)
The weight average molecular weight (Mw) and the number average molecular weight (Mn) were measured by gel permeation chromatography (“HLC-8320GPC” manufactured by Tosoh Corporation), dissolved in chloroform, and measured in terms of polystyrene.

(Melting point (℃))
Using a differential scanning calorimeter DSC (“DSC 214 Polyma” manufactured by NETZSCH Co., Ltd.), the measurement was performed at a heating rate of 10 ° C./min. The intersection of the baseline on the melting start side and the tangent of the inflection point Was the melting point.

(Crystallization temperature (℃))
Using a differential scanning calorimeter DSC (“DSC 214 Polyma” manufactured by NETZSCH), the exothermic peak when the sample melted at 180 ° C. was cooled at 10 ° C./min was defined as the crystallization temperature.

(Decomposition temperature (℃))
Using a thermogravimetric analyzer TGA (“DTG-60A” manufactured by Shimadzu Corporation), the temperature was raised at 10 ° C./min, and the intersection of the baseline and the tangent of the inflection point at the start of weight reduction was decomposed. It was.

(Melt flow index MFI (g / 10 min))
Using a melt flow rate measuring device (“Melt Indexer” manufactured by Toyo Seiki Seisakusho Co., Ltd.), the load was measured at 2.16 kg and the temperature was 190 ° C. according to JIS K 7210.

(Young's modulus (MPa))
The pellets of Example 1 and Comparative Example were compressed to a thickness of 1 mm at a temperature of 180 ° C., and dumbbell-shaped test pieces were cut out. The test piece was conditioned at 23 ° C. and 50% relative humidity before testing according to ASTM D638, measured at room temperature using a universal material testing machine (Instron), and the stress-strain diagram Young's modulus was calculated from the initial slope. In addition, Young's modulus was measured about five test pieces on the same conditions as the above.

(Tensile strength (MPa) and elongation at break (%))
The pellets of Example 1 and Comparative Example were compressed to a thickness of 1 mm at a temperature of 180 ° C., and dumbbell-shaped test pieces were cut out. The test piece was conditioned to 23 ° C. and 50% relative humidity before the test according to ASTM D638 and measured at a speed of 5 mm / min using a universal material tester (Instron). In addition, the tensile strength and breaking elongation were measured about five test pieces on the same conditions as the above.

(Evaluation of variation)
Regarding the Young's modulus, tensile strength, and elongation at break, from the measurement results of the five test pieces, the degree of variation in the measured value was expressed as a deviation from the arithmetic average value together with the arithmetic average, and was expressed as an average value ± deviation. The standard deviation was also obtained from the five measured values.

Synthesis Example 3-Hydroxybutyric acid (3HB) produced by fermentation was reacted with ethanol in the presence of a sulfuric acid catalyst for esterification, and purified by distillation to prepare 3-hydroxybutyric acid ethyl ester.

  Ethyl 3-hydroxybutyrate 50.0 g (37.8 mmol) and titanium tetraisopropoxide 540 mg (0.19 mmol) were placed in a three-necked flask, and ethanol produced by transesterification was distilled off at 140 ° C. under a nitrogen flow. The reaction was continued for 3 hours. Thereafter, the mixture was gradually heated under reduced pressure to obtain an oligomer having an average degree of polymerization of about 5 (number average molecular weight of about 800; m1 = about 5, m2 = 0 in the above formula (1)). The terminal carboxyl group was capped with an ethyl group to form an ethoxycarbonyl group.

Comparative Example 1
Poly (3-hydroxybutyric acid) (PHB) pellets provided by TerraVerdae Bioworks were used without adding the oligomers obtained in the synthesis examples.

Example 1
To 95 parts by weight of poly (3-hydroxybutyric acid) (PHB) pellets provided by TerraVerdae Bioworks, 5 parts by weight of the oligomer obtained in the synthesis example was added and melt-kneaded at 180 ° C. to prepare pellets.

Comparative Example 2
Instead of 5 parts by weight of the oligomer obtained in the synthesis example, pellets were obtained in the same manner as in Example 1 except that 5 parts by weight of a commercially available plasticizer (tributyl acetyl citrate (“Citroflex A4” manufactured by Vertellus)) was used. Was prepared.

  The results are shown in Table 1. Regarding Young's modulus, tensile strength, and elongation at break, a variation by 95% two-sided test was calculated based on five measured values, and a standard deviation was calculated. The variation is indicated by “±” after the average value, and the standard deviation is described in parentheses.

  As is clear from the results shown in Table 1, in Example 1, the tensile elongation (breaking elongation) increased and the Young's modulus and tensile strength decreased compared to Comparative Example 1, so that poly (3- Hydroxybutyric acid) (PHB) was found to be effectively plasticized. Moreover, compared with the comparative example 2, in Example 1, since tensile elongation (breaking elongation) is large and the Young's modulus is falling, the plasticizing effect is larger than the existing plasticizer. In particular, in Example 1, the melt flow index is large and the melt moldability can be improved. Furthermore, in Example 1, since the variation of a measured value is small, it is thought that the plasticizer of this invention has high compatibility with resin.

  Since the plasticizer of the present invention can plasticize the resin, it can be combined with the resin in various fields such as paints, inks, adhesives, adhesives, antistatic agents, electric / electronic materials, electric / electronic parts or equipment. It can be used for machine parts or equipment (for example, automobiles, aerospace materials, sensors, etc.). In particular, the resin composition can be easily molded by extrusion molding, injection molding, and the like, and is molded articles or molded members in various fields (for example, molded articles such as casings and housings), containers (food, daily necessities, electricity, electronic equipment, and the like). It can be suitably used for containers such as parts) and packaging materials such as films and sheets. In addition, since the polymer of 3-hydroxyalkanoic acid (for example, 3HB) also has biocompatibility, it can be used as a biocompatible material in the medical field (for example, medical equipment, instruments, parts, and members).

Claims (12)

  A plasticizer which is formed of a homopolymer or copolymer oligomer of 3-hydroxyalkanoic acid and has a free carboxyl group or alkoxycarbonyl group at the terminal. The plasticizer of claim 1, wherein the 3-hydroxyalkanoic acid comprises at least 3- _{hydroxyC 4-12} alkanoic acid.   The plasticizer according to claim 1 or 2, wherein the 3-hydroxyalkanoic acid contains at least 3-hydroxybutanoic acid.   The plasticizer according to any one of claims 1 to 3, wherein the 3-hydroxyalkanoic acid contains at least an R form of 3-hydroxybutanoic acid. Plasticizers according to claim 1 and a terminal carboxyl group is modified to form a C _1-10 alkoxycarbonyl group, and a number average molecular weight of the oligomer of from 180 to 3,000.   The resin composition containing resin and the plasticizer in any one of Claims 1-5.   The resin composition according to claim 6, wherein the resin contains a biodegradable resin having at least an ester bond or an amide bond as a linking group.   The resin composition according to claim 6 or 7, wherein the resin contains at least one selected from a polyester resin, a polyamide resin, a polyesteramide resin, a polyester carbonate resin, and a polycarbonate resin.   The resin composition according to any one of claims 6 to 8, wherein the resin contains a hydroxyalkanoic acid homopolymer or a copolymer.   The resin composition in any one of Claims 6-9 which contains the plasticizer in any one of Claims 1-5 in the ratio of 0.1-50 weight part with respect to 100 weight part of resin.   The molded object formed with the resin composition in any one of Claims 6-10.   A method for improving the plasticity of a resin by adding the plasticizer according to any one of claims 1 to 5 to the resin.