JP2002371175A - Polytrimethylene terephthalate resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composition capable of suppressing deformation when release from a mold and giving an excellent appearance. SOLUTION: This polytrimethylene terephthalate resin composition is obtained by compounding (B) 0.1-10 pts.wt. fatty acid ester of a higher alcohol into (A) 100 pts.wt. polytrimethylene terephthalate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polytrimethylene terephthalate resin composition which is small in warpage, excellent in moldability and excellent in appearance as well as suitable for large-sized molding.

[0002]

2. Description of the Related Art Thermoplastic polyesters typified by polyethylene terephthalate and polybutylene terephthalate are excellent in mechanical properties, heat resistance, chemical resistance, weather resistance, and electrical properties, and are used in a wide range of fields such as automotive materials and electric / electronic parts. Used in And with the expansion and diversification of applications,
In addition, high performance, special performance according to the use, and high quality are increasingly required. For example, a method of adding a fatty acid ester to a thermoplastic polyester resin is described in JP-A-11-71506 (fatty acid ester + fatty acid metal salt), JP-A-7-292223 (aromatic polybasic acid ester), and JP-A-6-65492 (polycarbonate + fatty acid ester);
No. 247259 (fatty acid ester);
No. 243641 (organic lubricant + silicone compound),
And so on.

As the thermoplastic polyester resin, polyethylene terephthalate and polybutylene terephthalate have been conventionally used. However, when a fatty acid ester is used for polyethylene terephthalate, a satisfactory injection-molded product can be obtained due to large deformation at the time of mold release. Did not. Further, when a fatty acid ester is used as polybutylene terephthalate, warpage and releasability of an injection molded product are improved, but the surface appearance, particularly the surface appearance of a large molded product, has been a problem.
As means for improving the surface appearance, it is conceivable to increase the injection pressure, the cylinder temperature or the mold temperature.However, as the resin temperature increases, the polymer is decomposed, and a molded product that can withstand use is obtained. There was no reality. When molding an injection-molded product, particularly a large-sized injection-molded product, there is a demand for a technique capable of suppressing deformation during release from a mold and obtaining an excellent surface appearance.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has been made under the circumstances described above, which does not have the above-mentioned problems, that is, a resin composition which suppresses deformation upon release from a mold and has an excellent surface appearance. The purpose is to provide things.

[0005]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that a resin composition comprising a polytrimethylene terephthalate polymer and a fatty acid ester of a higher alcohol is injection-molded. In this case, the present inventors have found that an excellent surface appearance is provided while suppressing deformation at the time of release from the mold, and have reached the present invention. That is, the present invention provides: (A) a polytrimethylene terephthalate resin composition comprising (B) a fatty acid ester of a higher alcohol in an amount of 0.01 to 5 parts by weight per 100 parts by weight of polytrimethylene terephthalate;

[0006] 2. (B) The fatty acid ester has 12 carbon atoms
2. The polytrimethylene terephthalate resin composition as described in 1 above, which is an ester composed of from 24 to 24 higher alcohols and a fatty acid having 12 to 24 carbon atoms. (C) As a component, furthermore, a fatty acid 0.0001-
3. The polytrimethylene terephthalate resin composition as described in 1 or 2 above, which is added in an amount of 1 part by weight; As a component (D), a fatty acid metal salt is further added in an amount of 0.01.
The polytrimethylene terephthalate resin composition according to the above 1, 2, or 3, wherein the composition is contained in an amount of 1 to 1 part by weight.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The polytrimethylene terephthalate (hereinafter sometimes abbreviated as “PTT”) in the present invention is a polyester polymer using terephthalic acid as an acid component and trimethylene glycol as a glycol component. Other acid components other than terephthalic acid include:
Aromatic dicarboxylic acids other than terephthalic acid, such as phthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid,
Diphenyl dicarboxylic acid, diphenyl ether dicarboxylic acid, diphenoxyethane dicarboxylic acid, diphenyl methane dicarboxylic acid, diphenyl ketone dicarboxylic acid, diphenyl sulfone dicarboxylic acid, etc .; succinic acid, adipic acid, sebacic acid, etc .; aliphatic dicarboxylic acids; cyclohexane dicarboxylic acid, etc. Cyclic dicarboxylic acid; oxydicarboxylic acids such as ε-oxycaproic acid, hydroxybenzoic acid, and hydroxyethoxybenzoic acid; In addition,
Terephthalic acid is preferably at least 80 mol% of the acid component.

[0008] As trimethylene glycol, 1,3
-Propanediol, 1,2-propanediol, 1,
It is selected from 1-propanediol, 2,2-propanediol or a mixture thereof, but from the viewpoint of stability, 1,3-propanediol is particularly preferred, and preferably 80% by mole or more of the glycol component. Other glycol components include ethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, octamethylene glycol, neopentyl glycol, cyclohexane dimethanol,
Xylylene glycol, diethylene glycol, polyoxyalkylene glycol, hydroquinone and the like are exemplified.

Further, a branched component such as tricarballylic acid, trimesic acid, trimellitic acid or the like having trifunctional or tetrafunctional ester-forming ability, or glycerin, trimethylolpropane, pentaerythritol, etc. May be copolymerized with trifunctional or tetrafunctional ester forming alcohols, in which case they are 1.0 mol% or less, preferably 0.5 mol% or less, more preferably 0.5 mol% or less of the total dicarboxylic acid component. Is 0.3
Mol% or less. Further, PTT may be used in combination of two or more of these copolymer components.

[0010] The method for producing PTT used in the present invention is as follows.
Although not particularly limited, for example, JP-A-51-1
Terephthalic acid or an ester-forming derivative thereof (for example, a lower alkyl ester such as dimethyl ester and monomethyl ester) by a method described in JP-A-40992, JP-A-5-262882, JP-A-8-31177, and the like. Trimethylene glycol or its ester-forming derivative is heated and reacted at a suitable temperature and time in the presence of a catalyst, and the resulting glycol ester of terephthalic acid is polymerized at a suitable temperature and time in the presence of a catalyst. To a degree of polycondensation reaction.

The PTT of the present invention preferably has a weight average molecular weight of 10,000 to 100,000,
Mw / Mn showing the molecular weight distribution is preferably from 1.5 to 4.5. Furthermore, it is preferable that 1-20% of molecules having a molecular weight of 100,000 or more are contained. Regarding the method for measuring the number average molecular weight and the molecular weight distribution, for example, the method for measuring the molecular weight is an osmotic pressure method, a terminal quantitative method,
It can be measured by the method C (gel permeation chromatography). For example, HL manufactured by Tosoh Corporation
Showa Denko HFIP as C-8120 and column
804-803 (two 30 cm columns), hexafluoroisopropanol (hereinafter "HFIP") as a carrier
) And PMMA manufactured by Polymer Laboratory as a standard sample at a temperature of 40 ° C and a flow rate of 0.5 ml /
Can be implemented in minutes.

Next, the fatty acid ester of a higher alcohol of the present invention will be described. Examples of the fatty acid ester of a higher alcohol include a fatty acid ester obtained by reacting a fatty acid with a monohydric higher alcohol. Fatty acids include capric acid, undecylic acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachiic acid, behenic acid, lignoceric acid, serotinic acid, heptacosanoic acid, montanic acid Acid, melicic acid, laccelic acid,
Undecylenic acid, oleic acid, elaidic acid, setleic acid, erucic acid, brassic acid, sorbic acid, linoleic acid, linolenic acid, arachidonic acid, propiolic acid, stearolic acid, 12-hydroxydodecanoic acid, 3-hydroxydecanoic acid, 16 -Hydroxyhexadecanoic acid, 10
-Hydroxyhexadecanoic acid, 12-hydroxyoctadecanoic acid, 10-hydroxy-8-octadecanoic acid, d
Examples thereof include l-erythro-9.10-dihydroxyoctadecanoic acid and the like, preferably a fatty acid having 12 to 24 carbon atoms. Specific examples thereof include stearic acid, myristic acid,
Behenic acid, montanic acid and the like.

The higher alcohol is a monohydric alcohol, preferably a higher alcohol having 12 to 24 carbon atoms. Specific examples include lauryl alcohol,
Stearyl alcohol, oilel alcohol and the like can be mentioned. Specific examples of fatty acid esters of higher alcohols include myristyl laurate, myristyl myristylate, myristyl stearate, palmityl laurate,
Palmityl palmitate, stearyl stearate, stearyl laurate, stearyl palmitate, beeswax,
Examples thereof include montanic acid wax and spermaceti, and particularly preferred is stearyl stearate.

The amount of fatty acid ester of higher alcohol is 0.01 to 5 parts by weight based on 100 parts by weight of PTT. If the amount is less than 0.01 part by weight, a lubricant effect cannot be obtained. If the amount exceeds 5 parts by weight, the screw slips at the time of molding and conversely, poor appearance due to unstable moldability occurs. In the present invention, fatty acid esters of two or more higher alcohols may be added at the same time, and there is no limitation. For example, stearyl stearate and palmityl palmitate may be added simultaneously.

When the resin composition of the present invention further contains 0.0001 to 1 part by weight of a fatty acid as the component (C), a composition more suitable for the purpose can be obtained. Specific fatty acids (C) include capric acid, undecylic acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid,
Palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachiic acid, behenic acid, lignoceric acid, serotinic acid, heptacosanoic acid, montanic acid, melicic acid, raccelic acid, undecylenic acid, oleic acid, elaidic acid, setreic acid, erucic acid , Brassic acid, sorbic acid, linoleic acid, linolenic acid, arachidonic acid, propiolic acid, stearolic acid, 12-hydroxydodecanoic acid, 3-hydroxydecanoic acid, 16-hydroxyhexadecanoic acid, 10-hydroxyhexadecanoic acid, 12-hydroxyoctadecanoic acid, 10-hydroxy-8-octadecanoic acid, dl-erythro-9.10-dihydroxyoctadecanoic acid and the like, especially lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, S Arin acid is preferred.

When the resin composition of the present invention further contains 0.01 to 1 part by weight of a fatty acid metal salt as the component (D), a PTT resin composition having more excellent mold release properties can be obtained. Specific examples of the fatty acid metal salt (D) include calcium dimyristate, magnesium dimyristate, calcium dipalmitate, magnesium dipalmitate, calcium distearate, magnesium distearate, and calcium (myristate-palmitate). ,
(Myristate-palmitate) magnesium, (myristate-stearate) calcium, (myristate-stearate) magnesium, (palmitate-stearate) calcium, (palmitate-stearate) magnesium. Of these, calcium (palmitate-stearate) and (palmitate-
Magnesium stearate).

Further, the PTT of the present invention includes those in which additives and fillers are added as required. For example, hindered phenolic antioxidants, hindered amine light stabilizers, stabilizers such as benzotriazole ultraviolet absorbers, glass fiber, carbon fiber, talc,
Wollastonite, inorganic fillers such as hydrotalcite, titanium oxide, carbon black, quinacridone,
Pigments such as iron oxide, titanium yellow, phthalocyanine, and aluminum powder; crystal nucleating agents such as boron nitride; solid lubricants such as graphite, molybdenum disulfide, grafted polyethylene, and PTFE; mold release agents such as ethylene wax and ethylene bis fatty acid amide , Polyethylene glycol, conductive carbon black and the like.

The PTT of the present invention is molded by a conventional molding method, for example, an injection molding method, and put into practical use. For use in the present invention, the PTT resins of the present invention can be used in blends with other thermoplastic resins or elastomers as desired. Hereinafter, the present invention will be described in more detail with reference to examples and the like, but the present invention is not limited to the examples and the like. The thermoplastic polyester, fatty acid metal salt, and main evaluation methods used in the examples are as follows.

[0019] (1) a thermoplastic polyester resin a-1: Intrinsic viscosity ^{1.01 × 10 2 cm 3 · g} -1 of polytrimethylene terephthalate a-2: Intrinsic viscosity ^{1.02 × 10 2 cm 3 · g} - Polyethylene terephthalate ¹ a-3: Polybutylene terephthalate with intrinsic viscosity of 1.01 × 10 ² cm ³ · g ⁻¹ (2) Fatty acid ester of higher alcohol b-1: Stearyl stearate b-2: Palmityl palmitate

(3) Measurement of Deformation (Sledding) Using a molding machine set under the following conditions, 120 × 80 mm
A large flat test piece (thickness: 3 mm) with a corner (having a single point pin gate at the center) is formed, and the test piece is placed on a flat surface plate. The point where the gap between the pieces was the largest) was measured as the deformation amount. Cylinder temperature 260 ° C, injection pressure 88.2MPa, mold temperature 8
0 ° C., cooling time 20 seconds.

(4) Measurement of Release Resistance (Releaseability) Under the molding conditions of (3) above, the force [N] applied to the protruding pin when the test piece was protruded from the mold was measured by a strain gauge method. . (5) Appearance Using the mold of the above (3), the injection pressure was 93.1, 88.
The surface gloss of each molded product was visually determined by changing to 2,83.3 MPa. ○: good, △: slightly poor, ×: bad

[0022]

Examples 1 to 5 and Comparative Examples 1 to 4 The components shown in Table 1 were mixed in the amounts (parts by weight) shown in Table 1 and the screw diameter was 25
melt kneading at 260 ° C. with a twin-screw extruder (ZSK-25 manufactured by Warner & Friedler Co., Ltd.)
Pelletized. After the pellets were dried at 120 ° C. for 5 hours, each evaluation was performed. Table 1 shows the results.

[0023]

[Table 1]

[0024]

The polytrimethylene terephthalate resin composition containing a fatty acid metal salt of the present invention has a small deformation upon release from a mold during injection molding, and has excellent moldability and appearance.

Claims (4)

[Claims] 1. A polytrimethylene terephthalate resin composition comprising (A) 100 parts by weight of polytrimethylene terephthalate and (B) 0.01 to 5 parts by weight of a fatty acid ester of a higher alcohol. 2. The fatty acid ester (B) having 12 to 12 carbon atoms.
The polytrimethylene terephthalate resin composition according to claim 1, which is an ester comprising 24 higher alcohols and a fatty acid having 12 to 24 carbon atoms. 3. Fatty acid is further added as a component (C).
2. The composition according to claim 1, wherein the amount is from 0001 to 1 part by weight.
Or the polytrimethylene terephthalate resin composition according to 2. 4. The polytrimethylene terephthalate resin composition according to claim 1, further comprising 0.01 to 1 part by weight of a fatty acid metal salt as the component (D).