JPH0696675B2 - Thermoplastic resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a thermoplastic resin composition, and more specifically, a thermoplastic resin having poor compatibility is improved in compatibility by blending a third component, It is an object of the present invention to provide a thermoplastic resin composition which improves the defects of both resins and gives a molded article having excellent mechanical properties such as impact strength, tensile strength and tensile elongation.

(Prior Art) Conventionally, many attempts have been made to solve the drawbacks of each thermoplastic resin by blending thermoplastic resins having different properties. However, heterogeneous polymers usually do not mix uniformly due to poor compatibility, forming a so-called "sea-island" structure, the "sea-island" interface is very weak, and the resulting composition is fragile, rather It has a drawback that mechanical strength and impact strength are lowered.

(Problems to be Solved by the Invention) By the way, the polyphenylene ether resin has mechanical properties,
It is used in many applications as an engineering plastic because it has excellent balanced properties such as excellent electrical properties, heat resistance, and good dimensional stability. It has the major drawback of poor properties, impact strength and chemical resistance. On the other hand, as engineering plastics with excellent chemical resistance, thermoplastic polyester resins (for example,
There are polyethylene terephthalate, polybutylene terephthalate, etc.) and polyamide resins (for example, nylon 6 and nylon 66). The former thermoplastic polyester resin has a high melting point and excellent mechanical strength, but since the heat distortion temperature under load is extremely low, it is usually used as a molding material by blending a large amount of glass fiber. . However, the thermoplastic polyester resin reinforced with glass fiber has poor surface properties of the molded product, the orientation of the glass fiber occurs during molding, the strength anisotropy of the molded product is extremely large, and the shrinkage anisotropy of the molded product is also large. Therefore, there is a defect that the molded product is warped.

By the way, in order to solve these drawbacks of the polyphenylene ether and the thermoplastic polyester resin, an attempt to melt-mix both of them has been proposed in JP-B-51-21664. However, the obtained compositions show typical incompatible properties because the properties derived from the molecular structures of them (for example, represented by SP value) are greatly different. That is, the mechanical properties are significantly lower than those expected from both values, and the molded articles obtained from this composition have
The appearance is also worse than that of a single product.

Therefore, the present inventors have found that the above drawbacks can be remarkably improved by further blending a styrene resin containing an epoxy group as the third component. However, it was very difficult to always obtain the excellent physical properties stably.

(Means for Solving the Problem) As a result of earnestly studying the above problem, that is, obtaining the excellent physical properties constantly, the present inventor has finally completed the present invention. That is, the present invention contains 5 to 95 parts by weight of a thermoplastic resin (A) having a melting point of 150 to 300 ° C., having at least one polar group selected from a carboxyl group and a hydroxyl group at the terminal or side chain, and an epoxy group. Styrene resin (B) 0.01
~ 50 parts by weight, epoxy group-free styrene resin (C)
0 to 90 parts by weight, and 0 to 90 parts by weight of a thermoplastic resin (D) having molecular compatibility with the styrene resin (C) for a total of 10
0 parts by weight, and the total amount of component (C) and component (D) is 5
In the thermoplastic resin composition which is at least parts by weight, the reaction product produced by the reaction between the component (A) and the component (B) is based on the total weight of the component (A), the component (B) and the component (D), The ratio (Mn) of the number average molecular weights of the component (A) and the component (B) which constitute 3.0% by weight or more and which constitute the reaction product.
(B) / Mn (A)) is in the range of 0.6 to 10.0, and the intrinsic viscosity of the component (A) in the composition is 0.5 dl / g or more. is there.

The thermoplastic resin (A) in the present invention is a thermoplastic resin having a carboxyl group at the terminal or side chain and at least one kind of polar group selected from a hydroxyl group and having a melting point of 150 to 300 ° C., for example, polyethylene terephthalate, Polypropylene terephthalate, polybutylene terephthalate, polycyclohexadimethylene terephthalate, polyoxyethoxybenzoate, polyethylene naphthalate, the above polyester constituents and other acid components and / or glycol components such as isophthalic acid, P-oxybenzoic acid, adipic acid, Sebacic acid, glutaric acid,
Polyesters and aromatic polyesters / polyethers obtained by copolymerizing acid components such as diphenylmethane dicarboxylic acid and dimer acid, glycol components such as hexamethylene glycol, diethylene glycol, neopentyl glycol, bisphenol A and neopentyl glycol alkylene oxide adducts. Block copolymers, aromatic polyester / polylactone block copolymers, polyesters in a broad sense such as polyarylate, Nylo 6, Nylon 6,
6, nylon 6,9, nylon 6,10, nylon 6,12, nylon 6 / 6,6, polyxylylene adipamide, polyhexamethylene terephthalamide, polyphenylene phthalamide, polyxylylene adipamide / hexa Examples include polyamides such as methylene adipamide, polyester amide elastomers, polyether amide elastomers, polyether ester amide elastomers, and dimer acid copolymerized polyamides, and may be a blend of a single resin or a plurality of resins or a copolymer thereof. Good. Particularly, those having a melting point of 200 ° C. or higher are preferable from the viewpoint of heat resistance. Usually, it is particularly preferable that the above polyester resin has an intrinsic viscosity of 0.5 or more as measured by measuring at 30 ° C. in a phenol / tetrachloroethane mixed solution (6/4 weight ratio). Polyamide usually has a relative viscosity (measured in 98% sulfuric acid according to JIS K 6810-1970)
Is preferably 1.8 or more, more preferably 2.0 or more.

The epoxy group-containing styrene resin (B) in the present invention includes glycidyl methacrylate, glycidyl acrylate, vinyl glycidyl ether, allyl glycidyl ether, hydroxyalkyl (meth) acrylate glycidyl ether, and polyalkylene glycol (meth) acrylate. Styrene-containing polymers such as polystyrene, acrylonitrile / styrene copolymers, styrene / butadiene copolymers obtained by copolymerization or graft copolymerization of epoxy group-containing copolymerizable unsaturated monomers such as glycidyl ether and glycidyl itaconate. An example is coalescence. The content of the epoxy group-containing copolymerizable unsaturated monomer is usually 0.5 to 30% by weight with respect to the resin (B),
It is preferably 1 to 20% by weight.

The epoxy group-free styrene-based resin (C) in the present invention includes homopolymers such as polystyrene, polychlorostyrene and poly α-methylstyrene, styrene / putadiene copolymers, styrene / isoprene copolymers. , Styrene / acrylonitrile copolymer, styrene / acrylonitrile / acrylate copolymer, styrene / acrylonitol / ptadiene copolymer, styrene / butadiene rubber modified polystyrene, EPDM rubber modified polystyrene, acrylic rubber modified styrene / acrylonitrile copolymer, Examples thereof include polystyrene-based thermoplastic elastomers such as styrene / maleic acid copolymers and hydrogenated styrene / butadiene block copolymers.

Furthermore, as the thermoplastic resin (D) in the present invention,
A resin having a molecular compatibility with the styrene resin (C) (a blend that is compatible in the molecular order and changes the Tg of the styrene resin (C) to give a single Tg), and specifically, a polyphenylene ether resin Is exemplified. As the polyphenylene ether resin, a general formula A resin having a structural unit represented by

Here, R ₁ , R ₂ , R ₃ and R ₄ are hydrogen, halogen, a hydrocarbon group, a substituted hydrocarbon group, a cyano group, an alkoxy group, a phenoxy group or a nitro group, and n represents the degree of polymerization. R ₁ , R ₂ ,
Specific examples of R ₃ and R ₄ include hydrogen, chlorine, bromine, iodine, methyl, ethyl, propyl, allyl, phenyl, benzyl, methylbenzyl, chloromethyl, prommethyl, cyanoethyl, cyano, methoxy, ethoxy, phenoxy and nitro. The group is raised. Specifically, for example, poly-2,6-dimethyl-1,4-phenylene ether, poly-2,6-diethyl-1,4-phenylene ether,
Poly-2,6-dipropyl-1,4-phenylene ether, poly-2,6-dimethoxy-1,4-phenylene ether, poly-2,6-dichloromethyl-1,4-phenylene ether, poly-2,6 -Dibromomethyl-1,4-phenylene ether,
Poly-2,6-diphenyl-1,4-phenylene ether, poly-2,6-ditolyl-1,4-phenylene ether, poly-
2,6-dichloro-1,4-phenylene ether and poly-
2,5-dimethyl-1,4-phenylene ether, poly-2,6
Examples include-dibenzyl-1,4-phenylene ether.

Preferred polyphenylene ether resins have the general formula
R ₁ and R ₄ are polymers having an alkyl group, particularly an alkyl group having 1 to 4 carbon atoms, and h is usually preferably 50 or more.

The component (C) and the component (D) may be obtained by polymerizing the monomer of the other component in the presence of one of the component polymers.

In addition to the composition other than the above in the composition of the present invention, for example,
Fibrous reinforcing materials such as glass fibers, graphite fibers, carbon fibers, silicon carbide fibers, metal fibers, twist-resistant organic fibers, flakes such as calcium carbonate, clay, silica, glass beads, talc, mica and wollastonite, or A powdered inorganic filler or the like, or a silane coupler, a titanium coupler, a zircoaluminate coupler or the like may be used in combination. Furthermore, the composition of the present invention promotes the reactivity of the epoxy group in the component (B) with the component (A),
Alternatively, it is preferable to use a catalyst in order to improve the affinity with the component (A) by ring opening of the epoxy group. The reaction between the component (A) and the epoxy group is effective even without a catalyst, but the reaction is remarkably promoted by using a catalyst. As the catalyst, it is generally preferable to add amines, phosphorus compounds, metal salts of Group Ia or IIa of the periodic table of the elements of monocarboxylic acids and / or dicarboxylic acids having 10 or more carbon atoms. Particularly preferred are trivalent phosphorus compounds such as tributylphosphine and triphenylphosphine, and metal salts of stearic acid such as calcium stearate and sodium stearate. When using these catalysts, one kind may be used alone, or two or more kinds may be used in combination. Further, the effect does not change even if the above catalyst is put in all at once or dividedly. The blending amount is not particularly limited, but is usually 3 parts by weight or less with respect to 100 parts by weight of the component (A),
It is preferably 0.03 to 2 parts by weight.

The blending ratio of the above components (A), (B), (C) and (D) can be appropriately changed depending on the desired physical properties, purpose, cost and the like, but usually the components (A), (B) and (C). And the total amount of (D) is 100 parts by weight, and the component (A) is 5-9
5 parts by weight, preferably 20-80 parts by weight, component (B) 0.01
-50 parts by weight, preferably 0.05-30 parts by weight, component (C) 0-90 parts by weight, preferably 0-75 parts by weight and component (D) 0-90 parts by weight, preferably 2-80 parts by weight. The total amount of the component (C) and the component (D) is 5 parts by weight or more.

If the added amount of the component (A) is too small, the chemical resistance may be deteriorated, and the components (C) and / or (D) may be added.
If the amount is too small, the molding shrinkage increases and the molded product sinks,
It causes warpage and causes a defect that deteriorates the surface characteristics. On the other hand, when the amount of the component (B) is too small, the compatibility between the component (A) and the component (C) and / or the component (D) is poor and the physical properties are deteriorated, which is not preferable.

In the composition of the present invention, the reaction product amount of the component (A) and the component (B) needs to be 3.0% or more based on the total amount of the component (A), the component (B) and the component (D), and more preferably It is 4.0% by weight or more. When the amount of the reaction product is small, the strength and elongation and impact resistance of the resulting composition are extremely lowered, which is not preferable.

As a method for increasing the amount of the reaction product, a method of increasing the epoxy group concentration of the component (B) or a method of increasing the carboxyl group concentration of the component (A) may be adopted. group content is preferably 50~3000mol / 10 ⁶ g, further 2000mol / 10 ⁶ g is desirable from 100. Further, the amount of the carboxyl group of the component (A) is preferably 50 to 200 mol / 10 ⁶ g. Even if the amount of the carboxy group is 200 mol / 10 ⁶ g or more, the effect is almost the same as that of less than that, rather the intrinsic viscosity of the component (A) cannot be maintained at 0.5 or more, and the strength and elongation of the composition is increased. It is not preferable because it decreases.

Further, in the composition of the present invention, the ratio (Mn) of the number average molecular weights of the component (A) and the component (B) in the reaction product measured by the following measurement method.
(B) / Mn (A)) (hereinafter abbreviated as γ) needs to be 0.6 to 10.0.

When γ is less than 0.6 or more than 10.0, the reaction product becomes very close to the property of either component (A) or component (B), and the effect as a compatibilizer can be sufficiently exhibited. In addition, the mechanical strength of the composition decreases, which is not preferable.

In the present invention, keeping the intrinsic viscosity of the component (A) at 0.5 or more, preferably 0.6 to 1.5 is important for improving the strength and elongation of the composition, which includes the components (A) and (B).
The reaction can be accomplished by lowering the concentration of the carboxy terminal in the system by using a component (A) having a high intrinsic viscosity, such as 0.7 to 1.8. Even if the intrinsic viscosity of the component (A) at the time of blending is less than 0.7, it can be achieved by adding a thickening substance such as a diepoxy compound or an oxazoline compound.

In the composition of the present invention, a crystal nucleating agent of the component (A) such as titanium oxide, carbon black or the like or a crystallization accelerator, for example, when the component (A) is an ethylene terephthalate polyester, depending on the use, purpose, etc., Compounded with a polyoxyalkylene compound compatible with the polyester, a polyhydric alcohol derivative, a higher fatty acid ester, a higher aliphatic metal salt, a polyvalent carboxylic acid ester, a high molecular weight aliphatic polycarboxylic acid salt, a polyhydric alcohol ester, etc. You may. Usually, the compounding amount of the crystal nucleating agent is up to about 50% by weight with respect to the composition, and the crystallization accelerator is 10% by weight with respect to the composition.
Up to a degree is preferable.

In addition, antioxidants, ultraviolet absorbers, stabilizers such as hydrolysis resistance improvers, plasticizers, lubricants, flame retardants, flame retardant aids, antistatic agents, colorants, conductivity imparting agents, slidability Modifiers (solid lubricants, liquid lubricants), polyfunctional crosslinking agents, impact modifiers (for example, rubber-like substances having Tg of 0 ° C or less, preferably -20 ° C or less, more preferably reactive group-containing rubber) ), And an additive for a conductivity-imparting agent (for example, polyacetylene fiber, metal powder, iron phosphate, carbon black, organic conductive polymer, etc.).

The method for producing the composition of the present invention is not particularly limited and may be any method. For example, it can be compounded by mechanically kneading with an extruder, a roll mill, a Banbury mixer or the like. A multi-stage kneading in which the other components are kneaded after kneading the component (A) and the component (B) may be used.

The composition of the present invention can be widely used for molding various molded parts and films, sheet-like products such as plates, fibrous products, tubular products, molded products such as containers, coating agents, adhesives, sealants, It can also be used as a modifier for other resins. Further, it can be formed into a film, a fiber or the like and further stretch-formed, or can be used as a secondary molded product.

(Examples) Hereinafter, the present invention will be described more specifically with reference to Examples, but the present invention is not limited thereto.

In the examples,% is based on weight.

Further, various measurements in the examples were carried out by the following methods.

(1) Tensile strength and elongation Measured according to ASTM D-638.

(2) Izod impact strength Measured with a notch according to ASTM D-256.

(3) Intrinsic viscosity of component (A) in the composition After removing the reaction product in the precipitate (component (A)) separated when measuring the amount of the reaction product in the composition, the component (A) The intrinsic viscosity of A) was measured at 30 ° C in a phenol / tetrachloroethane mixed solvent (6/4 weight ratio).

Examples 1 to 7 and Comparative Examples 1 to 9 Polyethylene terephthalate having an intrinsic viscosity of 1.0 or 0.63 dl / g, an epoxy group-containing styrene resin, an epoxy group-free styrene resin, and [η] of 0.58 (chloroform). (Measured at 30 ° C) at a temperature of 30 ° C), and mix predetermined amounts of poly-2,6-dimethyl-1,4-phenylene ether powder with a blender, and use a 30 mmφ twin-screw extruder (PCM-30, Ikegai Iron Works Co., Ltd.) to cylinder. The mixture was kneaded and extruded at a temperature of 280 to 300 ° C to obtain pellets. The obtained pellets were dried in a vacuum dryer at 120 ° C. for 5 hours and then made into a molded product by an injection molding machine (FS-75 type, manufactured by Nissei Plastic Co., Ltd.). Cylinder temperature at this time is 280-295 ℃
The mold temperature was 90 ° C. The physical property values of each of the obtained compositions are shown in Table 1.

In Table 1, PET-1) Polyethylene terephthalate with an intrinsic viscosity of 1.0 PET-2) Polyethylene terephthalate with an intrinsic viscosity of 0.63 *) Polybutylene terephthalate with an intrinsic viscosity of 1.0 *) Polybutylene terephthalate with an intrinsic viscosity of 0.70 Resin-3 ) To 6) a copolymer obtained by radical polymerization of styrene and glycidyl methacrylate with t-butyl peroxide as an initiator in xylene at 90 ° C,
The number average molecular weight (Mn) and epoxy group concentration of each are shown below.

However, Mn is calculated by gel permeation (GPC) in terms of polystyrene, and the epoxy group concentration is ¹³ C-NMR or IR.
It was measured by the difference spectrum method.

SEBS-7) Hydrogenated styrene-butadiene block copolymer with a number average molecular weight of about 100,000 PPO-8) Poly-2,6-dimethyl-1,4-phenylene ether (Effect of the invention) As apparent from Table 1, The composition of the present invention comprises the component (A)
By using the component (B) having an inherent viscosity of 0.5 dl / g and having an appropriate amount of epoxy groups and a number average molecular weight, reaction products of the component (A) and the component (B) are present. It can be seen that the compatibility of the components is improved, the state of uniform dispersion is achieved, and the strength, elongation and impact strength are improved.

Claims (1)

[Claims] 1. A melting point having at least one kind of polar group selected from a carboxyl group and a hydroxyl group at the terminal or side chain.
5 to 95 parts by weight of a thermoplastic resin (A) of 150 to 300 ° C., 0.01 to 50 parts by weight of a styrene resin (B) containing an epoxy group,
A total of 100 parts by weight of 0 to 90 parts by weight of an epoxy group-free styrene resin (C) and 0 to 90 parts by weight of a thermoplastic resin (D) having a molecular compatibility with the styrene resin (C). In a thermoplastic resin composition in which the total amount of (C) and component (D) is 5 parts by weight or more, the reaction product produced by the reaction between component (A) and component (B) is component (A),
Component (A) which occupies 3.0% by weight or more of the total weight of component (B) and component (D) and constitutes a reaction product.
And the number average molecular weight ratio of component (B) (Mn (B) / Mn
(A)) is in the range of 0.6 to 10.0, and the intrinsic viscosity of component (A) in the composition is 0.5 dl / g or more.