JP2968498B2 - Syndiotactic polystyrene based composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to syndiotactic polystyrene-based compositions. For more information,
The present invention relates to a modified composition containing a main component, a syndiotactic polystyrene-based resin, and a specific nucleating agent blended to improve its crystallization rate.

[0002]

2. Description of the Related Art Styrene-based resins produced by radical polymerization are amorphous plastics,
It is widely used in household goods, toys, packaging containers, furniture, synthetic paper and other industrial applications by being formed by methods such as extrusion and vacuum forming. However, a styrene-based resin produced by radical polymerization is not crystalline, and thus has a drawback of poor mechanical strength, heat resistance, and chemical resistance.

On the other hand, syndiotactic polystyrene (hereinafter also referred to as “SPS”) resin is crystalline, and has a high melting point up to about 270 ° C., unlike isotactic polystyrene resin, which is the same crystalline polystyrene. ing. Therefore, the syndiotactic polystyrene-based resin is superior in mechanical strength, solvent resistance, and electrical properties as compared with a conventional styrene-based resin produced by radical polymerization (Japanese Patent Laid-Open No. Sho 62-62).
No. 104818, JP-A-62-257948 and JP-A-62-257950). However, since the syndiotactic polystyrene base resin has a low crystallization rate, there is a problem that a high molding temperature is required to crystallize the syndiotactic polystyrene base resin during molding.

[0004] Therefore, a method for increasing the crystallization rate includes using a nucleating agent. For example, JP-A-1-201350 discloses the use of a salt of an organic phosphoric acid as a nucleating agent,
In addition, EP 312976 describes that metal salts of organic acids (<50 μm) and inorganic compounds (<
50 μm), the use of organophosphorus compounds and ionomers is disclosed. Further, JP-A-6-340
No. 786 discloses the use of an organic salt of an alkali metal as a nucleating agent and the use of cyclophosphatide as an auxiliary, and JP-A-7-247390 discloses a nucleating agent. It is disclosed that halogenated bisphthalimide is used.

However, no syndiotactic polystyrene-based composition having a sufficient crystallization rate has been obtained by any of the methods.

[0006]

SUMMARY OF THE INVENTION In view of the above, it is an object of the present invention to provide a syndiotactic polystyrene-based composition having a crystallization rate much higher than that of a conventional syndiotactic polystyrene-based resin. Is to provide.

[0007]

The present invention provides (A) 100 parts by weight of a syndiotactic polystyrene-based resin,
(B) Formula (I):

[0008]

[0009]

[0010]

Embedded image

Wherein R ¹ is an alkylene group having 1 to 5 carbon atoms, X is a halogen atom selected from the group consisting of F, Cl, Br and I, and a is an integer of 1 to 5. the related compound either et syndiotactic polystyrene-based composition comprising a selected the nucleating agent 0.01-5 parts by weight.

The nucleating agent has the formula (I):

[0013]

[0014]

[0015]

[0016]

[0017]

Embedded image

Wherein R ¹ is an alkylene group having 1 to 5 carbon atoms, X is a halogen atom selected from the group consisting of F, Cl, Br and I, and a is an integer of 1 to 5. Preferably, the compound is

Further, the nucleating agent has the formula ( II ):

[0020]

Embedded image

( Wherein , R ¹ represents an alkylene group having 1 to 5 carbon atoms and a represents an integer of 1 to 5 ).

Preferably, the nucleating agent is bis (phenylbromide) methane.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention comprises (A) 100 parts by weight of a syndiotactic polystyrene base resin, and (B)
Formula (I):

[0024]

[0025]

[0026]

Embedded image

Wherein R ¹ is an alkylene group having 1 to 5 carbon atoms, X is a halogen atom selected from the group consisting of F, Cl, Br and I, and a is an integer of 1 to 5. And 0.01 to 5 parts by weight of a nucleating agent selected from the group consisting of compounds and mixtures thereof.

The syndiotactic polystyrene base resin used in the present invention (hereinafter referred to as “SPS base resin”)
) Is a polystyrene-based resin having a predominantly syndiotactic configuration, in which the syndiotactic configuration is at least 75%, more preferably at least 85%.
Account for%.

The type of the syndiotactic polystyrene-based resin is not particularly limited, and examples thereof include polystyrene, polyalkylstyrene, polyhalogenated styrene, polyalkoxystyrene, polyvinylbenzoate and the like, and mixtures thereof. Further, a copolymer containing the monomer constituting the SPS base resin as a main component is also included.

Examples of the polyalkylstyrene include polymethylstyrene such as polyp-methylstyrene and polym-methylstyrene, polybutylstyrene such as polyethylstyrene and polyp-tert-butylstyrene, and polyisopropylstyrene. can give.
Examples of the polyhalogenated styrene include polychlorostyrene such as polybromostyrene and poly p-chlorostyrene. Examples of the polyalkoxystyrene include polymethoxystyrene and polyethoxystyrene.

Of these, polystyrene, poly p
-Methyl styrene, poly m-methyl styrene, poly p-
Tert-butylstyrene, polyp-chlorostyrene and styrene-p-methylstyrene copolymer are preferred.

The molecular weight of the SPS base resin used in the present invention is not particularly limited, but is preferably at least 10,000, more preferably at least 50,000.
It should have an average molecular weight of zero.

The SPS base resin may be in any form, for example, pellets, powders and the like.

The syndiotactic polystyrene base resin can be produced by a conventional method.

Next, in the present invention, in order to improve the crystallization speed of the SPS base resin, a nucleating agent and SP
From the S-based resin, a syndiotactic polystyrene-based composition is obtained.

The nucleating agent used in the present invention is represented by the formula (I):

[0037]

[0038]

[0039]

Embedded image

Wherein R ¹ is an alkylene group having 1 to 5 carbon atoms, X is a halogen atom selected from the group consisting of F, Cl, Br and I, and a is an integer of 1 to 5. It is used as the compound or we have selected.

As the compound represented by the above formula (I),
Even if the field formula (II)

[0042]

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Wherein R ¹ is an alkylene group having 1 to 5 carbon atoms , and a is an integer of 1 to 5 , and more specifically, for example, bis (phenylbromide) methane And so on.

The nucleating agent represented by the above formula (I ) has a benzene ring structure and has some compatibility with the SPS base resin. Furthermore, it is easy to handle in a temperature range around the melting point of the SPS base resin because it remains a powdery solid, and is suitable as a nucleating agent used to obtain the syndiotactic polystyrene base composition of the present invention.

In the present invention, the nucleating agent is added in an amount of 0.01 to 100 parts by weight of the SPS base resin.
The amount may be up to 5 parts by weight, preferably 0.1 to 3 parts by weight.

In the present invention, in order to improve the oxidation stability and the light stability, a phenol antioxidant,
Various additives such as an organic antiphosphoric agent containing a salt of an organic phosphoric acid or an organic phosphonic acid, a thioether antioxidant, and an ultraviolet absorber, a syndiotactic polystyrene-based composition within a range not to impair the effects of the present invention. Can be added.

In particular, by including a phenol antioxidant and / or an organic antiphosphorizing agent, the syndiotactic polystyrene composition of the present invention may be colored, It is possible to prevent the properties from deteriorating.

When the phenolic antioxidant and / or the organic phosphorus-based antioxidant is added, SP
It is preferable to add 0.001 to 5 parts by weight, preferably 0.01 to 3 parts by weight, based on 100 parts by weight of the S base resin.

Further, if necessary, a nonionic, cationic or anionic antistatic agent, an aliphatic carboxylate of an alkali metal, a pigment, a dye, a filler, a foaming agent, a flame retardant, a lubricant and an auxiliary agent may be used. Various additives can be added within a range that does not impair the effects of the present invention.

The method for producing the syndiotactic polystyrene-based composition of the present invention is not particularly limited and can be produced by a general method (ordinary method). For example, the SPS-based resin powder (or pellet) can be used. ), By blending the nucleating agent and other additives, or by first preparing the concentrates of the nucleating agent and other additives in a conventional manner, and then adding this concentrate to the SPS base resin. It can be produced by adding.

The syndiotactic polystyrene-based composition of the present invention can be prepared by a conventional molding method such as extrusion molding, injection molding, vacuum molding, or cross-linking blow molding.
Secondary processing can be performed on biaxially stretched films and sheets.

[0052]

The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

Example 1 Syndiotactic polystyrene-based resin having a melting point of 269 ° C. and a syndiotactic configuration of greater than 95% (Industrial Technology Research Institute)
Institute) Union Chemical Laboratories (sPS) 100
Parts by weight, bis (phenylbromide) meta as nucleating agent
(Saytex ^™ 8010) 0.3 parts by weight, antioxidant (Ciba
Irganox 1010 from Geigy
0.3 parts by weight and an antioxidant (U manufactured by GE Specialty Chemicals)
626) Blend 0.3 parts by weight and then extruder (C
Melt kneading using a SI mixing extruder)
A pellet (pellet 1) of the syndiotactic polystyrene base composition of the present invention was obtained.

[0054]

Example 2 Bis (phenylbromide) methane (Sayt
ex ^TM 8010) 0.8 parts by weight but using the give a pellet (pellet 2) of syndiotactic polystyrene-based compositions of the present invention in the same manner as in Example 1.

Example 3 Bis (phenylbromide) methane (Sayt
ex ^TM 8010) except using 2 parts by weight to give a pellet (pellet 3) of syndiotactic polystyrene-based compositions of the present invention in the same manner as in Example 1.

Comparative Example A pellet of the syndiotactic polystyrene base composition (comparative pellet) was obtained in the same manner as in Example 1 except that no nucleating agent was used.

[Evaluation] For each of the pellets 1 to 4 and the comparative pellets obtained in Examples 1 to 4 and Comparative Example, the half-crystallization time (t _1/2 ) at 248 ° C. was measured by using a thermal analyzer (Perkin-Elmer (Perkin Elmer)). Perkin Elmer) DS
It measured using C7). As a measuring method, the pellet was heated from room temperature to 320 ° C. at a rate of 10 ° C./min in a nitrogen atmosphere, the temperature was maintained at 320 ° C. for 3 minutes, and then the temperature was lowered to 248 ° C. at a rate of 300 ° C./min. And finally by maintaining the temperature at 248 ° C. for 15 minutes. The time at which crystallization of the pellet was completed to 50% (t _1/2 ) was recorded. Table 1 shows the evaluation results together with the amount of the nucleating agent used. The shorter the half-crystallization time (t _1/2 ), the faster the crystallization speed.

[0059]

[Table 1]

[0060] From Table 1, the crystallization rate of the syndiotactic polystyrene-based composition, it is found to be accelerated by the addition of bi scan (phenyl bromide) methane as a nucleating agent.

[0061]

According to the present invention, a syndiotactic polystyrene-based composition having a high crystallization rate can be obtained.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-1-201350 (JP, A) JP-A-6-340786 (JP, A) JP-A-7-247390 (JP, A) US Patent 3,886,131 (US , A) (58) Field surveyed (Int. Cl. ⁶ , DB name) C08L 25/00-25/18

Claims (3)

(57) [Claims] (A) Syndiotactic polystyrene
(B) Formula (I):  Embedded image(WhereR ¹ Is an alkylene group having 1 to 5 carbon atoms, X is F,
Halogen selected from the group consisting of Cl, Br and I
Atom, a represents an integer of 1 to 5)ThingLa
Synth comprising 0.01 to 5 parts by weight of a selected nucleating agent
Geotactic polystyrene based composition. 2. The nucleating agent of the formula ( II ): ( Wherein , R ¹ is an alkylene group having 1 to 5 carbon atoms , a is 1 to
Syndiotactic polystyrene-based composition according to claim 1, wherein the compound represented by 5 represents an integer of). 3. The syndiotactic polystyrene-based composition according to claim 2 , wherein the nucleating agent is bis (phenylbromide) methane.