JPH07286066A - Nucleator composition and polyolefin resin composition - Google Patents

Abstract

PURPOSE:To obtain an odorless nucleator compsn. which exhibits highly active clarifying and nucleating characteristics at a low content when compounded into a polyolefin resin by incorporating specific compds. into the compsn. CONSTITUTION:A nucleator compsn. contains a diacetal compd. (A) of formula I [wherein, when X<1> is 3,4-dimethlbenzylidene, then X<2> is a group of formula II (wherein R<1> is 1-3C alkyl, Cl, or methyloxymethyl) or 5,6,7,8-tetrahydro-2- naphthyl; and when X<2> is 3,4-dimethylbenzylidene, then X<1> is a group of formula II or 5,6,7,8-tetrahydro-2-naphthyl] and bis(O-3,4-dimethylbenzylidene)sorbitol (B) pref. in a wt. ratio (A/B) of (4:1)-(1:9).

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a nucleating agent composition and a polyolefin resin composition containing the nucleating agent composition.

[0002]

BACKGROUND OF THE INVENTION A dibenzylidene sorbitol compound (hereinafter abbreviated as "DBS compound") prepared by acetal condensation of an aromatic aldehyde and sorbitol in the presence of an acid catalyst is a core for a polyolefin resin composition. It has been widely used as an agent, and the present inventors have been proposing various DBS compounds by earnestly studying to provide a nucleating agent having more excellent properties.

However, since there are various demands for a nucleating agent, in order to apply it to a wide range of applications,
There is room for improvement.

Specifically, 1,3: 2,4-bis (O-benzylidene) sorbitol (hereinafter abbreviated as "DBS").
When using, the optical properties of the molded product obtained from the obtained polyolefin resin molded product, especially its transparency can be significantly improved, but there is a sufficient demand for fields requiring higher transparency. I'm not satisfied.

In order to solve such a problem, we have prepared 1,3: 2,4-bis (O-methylbenzylidene) sorbitol (hereinafter referred to as “the benzaldehyde”, which is prepared by using a methyl-substituted benzaldehyde as a starting material instead of benzaldehyde. Me
-DBS ". ) Was proposed (JP-A-53-1).
17044, JP-A-54-28348).

[0006] By applying this, it is possible to obtain a resin composition having a remarkably excellent transparency,
Methyl-substituted benzaldehyde is a compound that is also used as a fragrance and has an extremely good odor. Therefore, it is recognized that an odor is easily generated when the resin composition is heated and molded.

1,3: 2,4-bis (O-polyalkylbenzylidene) sorbitol (JP-A-56-45934)
Or having a different type and number of substituents on each aromatic ring,
A so-called asymmetric DBS compound (JP-A-59-129)
No. 51) provides a polyolefin resin composition suitable for the production of a molded product having excellent transparency, as well as the case of using Me-DBS, and has a drawback of Me-DBS, which is an odor during heat molding. The occurrence of is greatly suppressed.

On the other hand, unlike the conventional "dispersion type" of nucleating agents such as metal salts and silica, the DBS compound is melted at a temperature equal to or higher than its melting point and uniformly dissolved in the resin. Since it is a "dissolution type" nucleating agent, it is important to melt-mix the nucleating agent at a high speed at the time of molding the polyolefin resin for efficient molding.

Therefore, if the nucleating agent used has a high melting point, there is the disadvantage that the molding of a resin composition containing such a nucleating agent must be carried out under severe conditions at high temperatures. In order to mold at a temperature below the melting point of the nucleating agent, an extra step of preparing a high-concentration masterbatch by heating and melting the nucleating agent and the polyolefin resin at a high temperature above the melting point of the nucleating agent in advance. is necessary. Therefore, the lower the melting point of the nucleating agent used,
It can be said that the workability of the polyolefin resin composition containing this during molding is excellent.

Further, these DBS compounds generally have sublimability near the melting point. For this reason, it causes stains on the mold during molding and stains on the molding model, resulting in deterioration of workability.

However, according to the research conducted by the present inventors, the higher the melting point of the nucleating agent used, the more the polyolefin resin composition containing the nucleating agent has the problem of workability, but the excellent transparency and other properties. Tend to give molded bodies. Therefore, the workability based on the low melting point of the nucleating agent is improved,
At the same time, improving the transparency and other properties of the molded product is a trade-off difficult problem.

For example, a polyolefin resin composition containing the 1,3: 2,4-bis (O-polyalkylbenzene) sorbitol or Me-DBS compound as a nucleating agent has excellent properties in transparency and other properties. Although it gives a molded product having the above, the melting point of the nucleating agent contained therein is as high as about 260 ° C. or more, and therefore the molded product usually has to be molded under high temperature conditions. Therefore, in order to obtain the excellent nucleating agent effect of the DBS compound in the general molding processing field where only heat processing conditions of about 260 ° C. or less can be adopted, a step of preparing a high-concentration masterbatch at a temperature equal to or higher than the melting point of the applied nucleating agent. It was accompanied by certain difficulties such as requiring extra. Further, the problem of poor moldability due to the sublimability of the nucleating agent during molding has not been solved.

The present inventors have previously proposed a novel and useful diacetal composition which solves the above problems and a polyolefin resin composition prepared by blending the composition as a nucleating agent (JP-A-2-206627). issue). This is because a nucleating agent composition mainly containing an asymmetric diacetal having a specific structure having an aromatic ring having a dimethyl group or a trimethyl group as a substituent and an aromatic ring having no substituent has been known so far. Its melting point is much lower than that of similar compounds,
Moreover, it was found that the sublimability is small, and that the resin composition containing the nucleating agent composition not only greatly improves the processability but also gives a molded article excellent in transparency and various other properties. It was made based on.

By the way, as the dimethyl compound, 2,4
-, 2,5-, 3,4- and 3,5-di-substituted products are mentioned, and the trimethyl form includes 2,4,6- and 3,4,5-tri-substituted products.

[0015]

DISCLOSURE OF THE INVENTION The present invention has an excellent transparency-improving effect on a polyolefin resin with a smaller blending amount, has a low melting point of 250 ° C. or lower, and produces odor and does not have a nucleating agent composition. It is an object of the present invention to provide a novel and useful nucleating agent composition which does not generate fish eyes due to dispersion, and a polyolefin resin composition containing the nucleating agent composition.

[0016]

DISCLOSURE OF THE INVENTION The present inventors have found that the positions of the substituents, the types of the substituents, the number of the substituents, and the like of various symmetric and asymmetric DBS compounds as nucleating agents for polyolefin resins. Of the asymmetric DBS-based compound having a specific structure and a symmetric DBS-based compound having a specific structure, beyond the expectations of conventional combinations of nucleating agents. Only the mixed system exhibits a particularly remarkable predetermined effect as compared with other single systems and mixed systems, that is, a low melting point, a highly active clearing nucleating agent property even in a small amount of addition, odorlessness and low It was found that the effects such as the scattering property are exerted on the polyolefin resin, and the present invention has been completed based on such knowledge.

That is, the nucleating agent composition according to the present invention is characterized by containing the following asymmetric DBS compound (component A), symmetric DBS compound (component B) and, if necessary, component C. And It is characterized by containing.

[0018]

[Chemical 4] [In the formula, when X ¹ represents a 3,4-dimethylbenzylidene group, X ² represents a group represented by the general formula (2) or a 5,6,7,8-tetrahydro-2-naphthyl group. When X ² represents a 3,4-dimethylbenzylidene group, X ¹ represents a group represented by the general formula (2) or a 5,6,7,8-tetrahydro-2-naphthyl group. ]

[0019]

[Chemical 5] [In the formula, R ¹ represents an alkyl group having 1 to 3 carbon atoms, a chloro group or a methyloxymethyl group. ]

[0020]

[Chemical 6] [In the formula, X ³ is a group represented by the general formula (2) or 5, 6,
It represents a 7,8-tetrahydro-2-naphthyl group. ]

According to the present invention, the following excellent advantages are achieved. (1) The resin composition of the present invention has substantially no odor during molding. (2) The molding cycle time is shortened by improving the crystallization temperature. (3) Since the nucleating agent composition of the present invention has a low melting point, it can be molded at a low temperature, and furthermore, fisheye formation due to incomplete melting of the nucleating agent is prevented. (4) The resin composition of the present invention does not generate sink marks,
Moreover, even when the pigment is dispersed, molding can be performed without causing volume shrinkage. (5) Stretched films can be produced with improved dimensional stability. (6) The molded product obtained from the resin composition of the present invention has significantly improved transparency. (7) The molded product also has improved gloss. (8) The molded product is also excellent in mechanical and thermal properties such as elastic modulus, impact resistance, and heat distortion temperature. (9) Since almost no mold stain is observed during molding, continuous molding is facilitated. (10) When a specific tertiary aliphatic amine, such as distearylmethylamine or stearyldiethanolamine, is uniformly mixed in advance with the nucleating agent, the transparency of the resin composition is further improved.

The reason why the nucleating agent composition having a specific composition according to the present invention exhibits such a particularly excellent nucleating agent effect is not yet sufficiently clear.

In the nucleating agent composition according to the present invention, the compounding ratio (weight basis) of the A component and the B component is not particularly limited as long as a predetermined effect can be obtained.
Ingredients = 4/1 to 1/9 are recommended. If it is out of this range, the effect of the nucleating agent is lowered, and fish eyes tend to be generated due to the high melting point, which is not preferable.

Further, the mixing ratio (weight basis) of the C component to the total amount of the A component, the B component and the C component is not particularly limited as long as a predetermined effect can be obtained, but C component / (A It is recommended that component + B component + C component) be 0.4 or less. If the amount is out of this range, the effect of the nucleating agent tends to decrease, which is not preferable.

In the components A, B and C, the compound of the general formula (2) in which R ¹ is a methyloxymethyl group is a newly discovered compound, while R ¹ excluding the methyloxymethyl group is The compounds having are all known compounds.

Each of the components A, B and C can be easily produced by a known method. Further, the novel compound represented by the general formula (2) in which R ¹ is a methyloxymethyl group can be easily produced according to the same known method. Therefore, the nucleating agent composition according to the present invention can be prepared by mixing the component A and the component B, and if necessary, the component C, respectively, in a predetermined ratio.

Further, by reacting sorbitol with a specific substituted benzaldehyde or an appropriate mixture of 5,6,7,8-tetrahydro-2-naphthylaldehyde and 3,4-dimethylbenzaldehyde, the component A is mixed in a predetermined ratio. The B component and the B component can also be manufactured all at once. An example of this specific method is shown in the production example described later.

The nucleating agent composition according to the present invention is not only used as a nucleating agent for a polyolefin resin, which will be described in detail below, but also a gelling agent, a viscosity modifier, a thixotropic agent, which brings about the effect of eliminating the fluidity of a liquid substance, It functions as an anti-sagging agent for paints, inks, adhesives, etc., an oil-water separating agent that has the effect of adsorbing oil on water and in water, a flocculant, etc., adhesives, paints, resin modification, solid fragrance, water treatment Agents, solidification / collection of spilled oil, fragrances, cosmetics, civil engineering / construction materials, lubricating oils, rust preventives, pesticides, pharmaceuticals, non-medical products, solid fuels, inks, glues, etc. The same applies in the fields that have been used.

The present invention also provides a useful polyolefin resin composition containing the nucleating agent composition.

The blending amount of the nucleating agent composition according to the present invention with respect to the polyolefin resin is not particularly limited as long as a predetermined effect can be obtained, and can be appropriately selected. 0 per department.
The amount is about 0.5 to 3 parts by weight, preferably about 0.07 to 1 part by weight. By blending within these ranges, the effects prescribed by the present invention can be sufficiently obtained.

As a method of adding the nucleating agent composition, a one-step addition method is preferable, but for example, a two-step method by addition in the form of a high-concentration masterbatch of about 2 to 15% may be adopted.

Examples of the polyolefin resin to which the nucleating agent according to the present invention is applied include polyethylene resins and polypropylene resins, and more specifically, high density polyethylene, medium density polyethylene, linear polyethylene,
Ethylene copolymer having an ethylene content of 50% by weight or more, propylene homopolymer, propylene copolymer having a propylene content of 50% by weight or more, butene homopolymer, butene copolymer having a butene content of 50% by weight or more, methylpentene homopolymer, methylpentene content of 50% by weight or more Examples thereof include methyl pentene copolymers and polybutadienes.

The above copolymer may be a random copolymer or a block coponomer. The stereoregularity of these resins may be isotactic or syndiotactic.

Specific examples of the comonomer capable of forming the above copolymer include α-olefins such as ethylene, propylene, butene, pentene, hexene, heptene, octene, nonene, decene, undecene, and dodecene;
Examples thereof include bicyclo-type monomers such as endomethylenecyclohexene, methyl (meth) acrylate, (meth) acrylates such as ethyl (meth) acrylate, vinyl acetate and the like.

In order to further improve the transparency of the polyolefin resin, for example, known nucleating agents such as diacetals, alkyl esters such as tetrahydrophthalic acid and hexahydrophthalic acid, phthalic acid and trimellitic acid are used. Compounding with alkyl esters, alkyl esters of adipic acid or azelaic acid, or tricarballylic amide compounds such as tricarballylic tricyclopentylamide, tricarballylic tricyclohexylamide, tricarballylic tris (2-methylcyclohexylamide) be able to.

Further, a conventionally known modifier for polyolefin can be added to the polyolefin resin composition according to the present invention as appropriate depending on the purpose of use and its application within a range that does not impair the effects of the present invention. .

As such a modifier for polyolefin,
Examples thereof include various additives described in "Positive List of Additives" (October 1990) edited by the Council for Hygiene of Polyolefins, and more specifically, stabilizers (metal compounds, epoxy compounds, nitrogen). Compounds, phosphorus compounds, sulfur compounds, etc.), ultraviolet absorbers (benzophenone compounds, benzotriazole compounds, etc.), antioxidants (phenolic compounds, phosphite compounds, sulfur compounds, etc.), surfactants, Lubricants (aliphatic hydrocarbons such as paraffin and wax, higher fatty acids having 8 to 22 carbon atoms, higher fatty acid metals having 8 to 22 carbon atoms (Al, Ca, M
g, Zn) salt, fatty acid having 8 to 18 carbon atoms, 8 to 2 carbon atoms
2 aliphatic alcohols, polyglycols, 4 to 2 carbon atoms
Esters of 2 higher fatty acids and aliphatic monohydric alcohols having 4 to 18 carbon atoms, higher fatty acid amides having 8 to 22 carbon atoms, silicone oil, rosin derivatives, etc., fillers (talc, hydrotalcite, mica, zeolite) , Perlite, diatomaceous earth, calcium carbonate, glass fiber, etc.), foaming agents, foaming aids, polymer additives, plasticizers, crosslinking agents,
Crosslinking accelerator, antistatic agent, antifogging agent, polymer alloy component (rubber such as block SBR or random SBR and hydrides thereof, polystyrene, etc.), flame retardant, dispersant, organic / inorganic pigment, dye, processing Various additives such as auxiliary agents are exemplified.

In producing the resin composition, any conventionally known method can be applied. For example, the nucleating agent composition of the present invention is blended with a polyolefin resin using a tumbler or a mixer. After that, final molding may be carried out. Alternatively, the nucleating agent composition may be blended with the resin in advance and pelletized, and then final molding may be carried out. The nucleating agent and the organic amine may be blended in advance and then molded by the above method.

Further, when molding the resin composition according to the present invention, any conventionally known molding method such as injection molding, extrusion molding, blow molding, pressure molding, rotational molding, film molding and the like can be adopted.

The polyolefin resin composition according to the present invention is applied in various fields similar to those where a polyolefin resin composition prepared by blending DBSs as a nucleating agent composition has been used, more specifically. , Medical instruments such as disposable syringes, infusions / transfusion sets, blood collection devices that are sterilized by heat or radiation; packages of foods, plants, etc. that are sterilized by radiation; various kinds of clothing cases, containers for storing clothing, etc. Cases; cups for heat-filling food; packaging containers for retort foods; microwave oven containers;
Containers such as cans and bottles for beverages such as juice and tea, cosmetics, pharmaceuticals, shampoos; containers and caps for seasonings such as miso and soy sauce; cases for food such as water, rice, bread and pickles It is suitable as a material for containers; miscellaneous goods such as refrigerator cases; stationery; electrical / mechanical parts; automobile parts.

[0041]

EXAMPLES The present invention will be described in detail below with reference to Examples and Comparative Examples. The evaluation in each of the following examples was performed by the following method.

Melting point (Tm) of the nucleating agent composition is shown by an exothermic peak temperature when the temperature is raised from room temperature at 20 ° C./min using a differential scanning calorimeter.

Transparency (Haze value) of the polyolefin resin composition The haze (%) and gloss were measured using a haze meter (JIS K 6714, JIS K 6717). The smaller the haze, the better the optical properties. (In addition, as a result of the measurement, in the examples and the comparative examples, the resin compositions containing the DBS compound showed good gloss.)

Degree of Fish Eye Occurrence Visually observing the surface of the test piece obtained by injection molding,
Based on the number of test pieces in which the undispersed nucleating agent was observed in 30 test pieces, evaluation was performed in the following three grades. ◯: No fish eyes were found ×: Fish eyes were found

Degree of generation of odor 30 g of the pellet was sealed in a 200 ml glass bottle, and 1
After leaving it in a constant temperature bath at 30 ° C. for 1 hour, it is judged by the presence or absence of its odor. ◯: No odor is observed Δ: Some odor is observed ×: Odor is observed

Production Example 1 Powdered sorbit 1 was placed in a 1.5-liter reaction can equipped with a stirring blade, a condenser with a decanter, a thermometer and a charging port.
8.2 g (0.1 mol), 3,4-dimethylbenzaldehyde 13.4 g (0.1 mol), p-chlorobenzaldehyde 14.3 g (0.1 mol), cyclohexane 20
0 ml, 50 ml of methanol and 2.0 g of p-toluenesulfonic acid were charged, the temperature was raised, and the produced water and methanol were discharged out of the system under reflux. Stop the reaction in 1.5 hours,
After cooling, neutralizing, washing with water, filtering, drying, and 39.3 g of the desired product.
Got The purity of the obtained target product (by gas chromatography, the same applies hereinafter) is 99.8%, and the reaction yield is 92.
It was 3%. The composition of the target product (the present nucleating agent 1) (by gas chromatography; the same applies hereinafter) was as follows. Also, the melting point of this nucleating agent 1 is 233 to 234 ° C.
Met.

Component A 1,3-O-3,4-dimethylbenzylidene-2,4-Op-chlorobenzylidene sorbitol and 1,3-Op-chlorobenzylidene-2,4-O-3, Mixture with 4-dimethylbenzylidene sorbitol 52% B component 1,3: 2,4-bis (O-3,4-dimethylbenzylidene) sorbitol 23% C component 1,3: 2,4-bis (Op -Chlorobenzylidene) sorbitol 25%

Production Example 2 14.3 g (0.1 mol) of p-chlorobenzaldehyde
Instead of p-methyloxymethylbenzaldehyde 1
32.6 g (yield: 75.8%) of the desired product was obtained in the same manner as in Production Example 1 except that 5.5 g (0.1 mol) was used. The composition of this reaction product (the present nucleating agent 2) was as follows. The melting point of the present nucleating agent 2 was 219 to 220 ° C.

Component A 1,3-O-3,4-dimethylbenzylidene-2,4-Op-methyloxymethylbenzylidenesorbitol and 1,3-O
-P-methyloxymethylbenzylidene-2,4-O-3,
Mixture with 4-dimethylbenzylidene sorbitol
51% B component 1,3: 2,4-bis (O-3,4-dimethylbenzylidene) sorbitol 23% C component 1,3: 2,4-bis (Op-methyloxymethylbenzylidene) sorbitol 26%

Production Example 3 p-Chlorobenzaldehyde 14.3 g (0.1 mol)
Instead of, 13.6 g of p-ethylbenzaldehyde
The reaction was performed in the same manner as in Production Example 1 except that (0.1 mol) was used to obtain 33.4 g of the desired product (yield 80.0%). The composition of this reaction product was as follows:

Component A 1,3-O-3,4-dimethylbenzylidene-2,4-Op-ethylbenzylidene sorbitol and 1,3-Op-ethylbenzylidene-2,4-O-3, Mixture with 4-dimethylbenzylidene sorbitol 52% B component 1,3: 2,4-bis (O-3,4-dimethylbenzylidene) sorb beer 23% C component 1,3: 2,4-bis (Op -Ethylbenzylidene) sorbitol 25%

To this, 1,3: 2,4-bis (Op-ethylbenzylidene) sorbitol and 1,3: 2,4-bis (O-3,4-dimethylbenzylidene) sorbitol were mixed, Finally, a nucleating agent composition (present nucleating agent 3) having the following composition was prepared.
The melting point of the present nucleating agent 3 was 232 to 234 ° C.

Component A 1,3-O-3,4-dimethylbenzylidene-2,4-Op-ethylbenzylidene sorbitol and 1,3-Op-ethylbenzylidene-2,4-O-3, Mixture with 4-dimethylbenzylidene sorbitol 30% B component 1,3: 2,4-bis (O-3,4-dimethylbenzylidene) sorber beer 40% C component 1,3: 2,4-bis (Op -Ethylbenzylidene) sorbitol 30%

Production Example 4 14.3 g (0.1 mol) of p-chlorobenzaldehyde
Instead of using 5,6,7,8-tetrahydro-2-naphthylaldehyde 16.0 g (0.1 mol), the reaction was conducted in the same manner as in Production Example 1 to obtain 33.4 g of the desired product (yield 75 .9%) was obtained. The composition of this reaction product (the present nucleating agent 4) was as follows. The melting point of the present nucleating agent 4 is 222 to 225.
It was ℃.

Component A 1,3-O-3,4-dimethylbenzylidene-2,4-O-5,6,7,8-tetrahydro-2-naphthylsorbitol and 1,3-O-5,6,7 , 8-Tetrahydro-2-naphthyl-2,4-O-3,4-dimethylbenzylidene sorbitol mixture 52% B component 1,3: 2,4-bis (O-3,4-dimethylbenzylidene) sorbitol 23 % C component 1,3: 2,4-bis (O-5,6,7,8-tetrahydro-2-naphthyl) sorbitol 25%

Example 1 With respect to an isotactic random polypropylene resin having an ethylene content of 2.0% by weight (hereinafter abbreviated as "polypropylene A"), the present nucleating agent 1, tetrakis [methylene-] was used.
3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane (trade name, Irganox 1010, manufactured by Ciba Geigy) and calcium stearate are added in the following composition for 5 minutes by a Henschel mixer. And then kneaded at 240 ° C. with a Labo Plastomill extruder and extruded to obtain pellets by a water cooling method. The pellets were injection-molded at 230 ° C. to obtain a sheet having a thickness of 1.0 mm, which was used as a sample to evaluate its characteristics. The results obtained are shown in Table 1.

Polypropylene A 100 parts by weight Nucleating agent 1 0.2 parts by weight Irganox 1010 0.05 parts by weight Calcium stearate 0.03 parts by weight

Examples 2 to 4 The nucleating agents 2 to 4 were blended in place of the nucleating agent 1 to obtain resin compositions, and the characteristics of the resin compositions were evaluated according to Example 1. The results obtained are shown in Table 1.

Comparative Example 1 Bis (p-chlorobenzylidene) sorbitol (melting point 251 to 253 ° C., comparative nucleating agent 1) was blended in place of the present nucleating agent 1 to obtain a resin composition. It was evaluated according to. The results obtained are shown in Table 1.

Comparative Example 2 Bis (p-methylbenzylidene) sorbitol (melting point: 255 to 260 ° C., comparative nucleating agent 2) was blended in place of the present nucleating agent 1 to obtain a resin composition, and the characteristics of this resin composition were obtained in Example 1. It was evaluated according to. The results obtained are shown in Table 1.

Comparative Example 3 2,4-dimethylbenzylidene-benzylidene sorbitol (melting point 234 to 235 ° C., comparative nucleating agent 3) was blended in place of the present nucleating agent 1 to obtain a resin composition, and the characteristics of this resin composition were evaluated. Evaluation was made according to 1. The results obtained are shown in Table 1.

Comparative Example 4 A resin composition was obtained in the same manner as in Example 1 except that the present nucleating agent 1 was not added, and the characteristics of this resin composition were evaluated according to Example 1. The results obtained are shown in Table 1.

Example 5 A resin composition obtained by mixing 2 parts by weight of the present nucleating agent 1 with 100 parts by weight of a linear low-density polyethylene was mixed with a Henschel mixer for 5 minutes and then extruded at 240 ° C. It shape | molded and created the masterbatch pellet (henceforth "pellet A"). At the same time, the same linear low-density polyethylene pellet as described above (hereinafter referred to as "pellet B") was prepared from the powder. Both were mixed at a ratio of Pellet A / Pellet B = 1/9 and then extruded at 200 ° C. to form a 1.0 mm thick sheet, and its characteristics were evaluated. The results obtained are shown in Table 2.

Examples 6 to 8 The properties of resin compositions prepared by blending the prescribed nucleating agent compositions (the present nucleating agents 2 to 4) were evaluated in accordance with Example 5. The results obtained are shown in Table 2.

Comparative Example 5 A resin composition was obtained by mixing Comparative Nucleating Agent 1 in place of the present Nucleating Agent 1, and the characteristics of this resin composition were evaluated according to Example 5. The results obtained are shown in Table 2.

Comparative Example 6 A resin composition was obtained by mixing Comparative Nucleating Agent 2 in place of the present Nucleating Agent 1, and the characteristics of this resin composition were evaluated according to Example 5. The results obtained are shown in Table 2.

Comparative Example 7 A resin composition was obtained by mixing Comparative Nucleating Agent 3 in place of the present Nucleating Agent 1, and the characteristics of this resin composition were evaluated according to Example 5. The results obtained are shown in Table 2.

Comparative Example 8 A resin composition was obtained in the same manner as in Example 5 except that the nucleating agent 1 was not added, and the characteristics of this resin composition were evaluated according to Example 5. The results obtained are shown in Table 2.

[0069]

EFFECT OF THE INVENTION The polyolefin resin composition according to the present invention has not only the highest degree of transparency but also no generation of odor due to thermal decomposition during molding. Moreover, since the melting point of the nucleating agent composition is 250 ° C. or lower, which is remarkably low as compared with the melting points of the conventional DBSs having excellent performance, the molding temperature can be reduced.

Further, even when applied to a resin such as polyethylene which is molded at a relatively low temperature, DB as a nucleating agent is used.
It is easy to suppress the formation of fish eyes due to the fact that Ss are not completely melted.

The nucleating agent composition according to the present invention can obtain the above-mentioned predetermined effects in an extremely small amount as compared with conventionally known nucleating agent compositions.

[Table 1]

[Table 2]

Claims (6)

[Claims] 1. A nucleating agent composition comprising the following components A and B: Component A: diacetal compound represented by the general formula (1) [In the formula, when X ¹ represents a 3,4-dimethylbenzylidene group, X ² represents a group represented by the general formula (2) or a 5,6,7,8-tetrahydro-2-naphthyl group. When X ² represents a 3,4-dimethylbenzylidene group, X ¹ represents a group represented by the general formula (2) or a 5,6,7,8-tetrahydro-2-naphthyl group. ] [Chemical 2] [In the formula, R ¹ represents an alkyl group having 1 to 3 carbon atoms, a chloro group or a methyloxymethyl group. ] Component B: Bis (O-3,4-dimethylbenzylidene) sorbitol 2. The nucleating agent composition according to claim 1, wherein the A component / B component is 4/1 to 1/9 (weight basis). 3. A nucleating agent composition further comprising, as the component C, an acetal compound represented by the general formula (3). [Chemical 3] [In the formula, X ³ is a group represented by the general formula (2) or 5, 6,
It represents a 7,8-tetrahydro-2-naphthyl group. ] 4. C component / (A component + B component + C component)
Is 0.4 or less (weight basis), The nucleating agent composition according to claim 3. 5. A polyolefin resin and claims 1 to 4.
A polyolefin resin composition containing the nucleating agent composition according to claim 1. 6. A polyolefin resin composition comprising 0.05 to 3 parts by weight of the nucleating agent composition according to any one of claims 1 to 4 with respect to 100 parts by weight of the polyolefin resin.