JPS62153338A - Easily slidable polyester resin composition - Google Patents

Abstract

PURPOSE:To obtain the title composition which is excellent in moldability and can give a molding excellent in impact resistance, tensile strength and sliding characteristics, by mixing an aromatic polyester with a glycidyl group-containing copolymer, a linear polyolefin and a fatty acid ester (partial saponificate). CONSTITUTION:100 pts. wt. aromatic polyester (A) (e.g., polybutylene terephthalate) is mixed with 1-11 pts. wt. glycidyl group-containing copolymer (B) comprising an alpha-olefin and a glycidyl ester of an alpha, beta-unsaturated acid (e.g., ethylene/glycidyl methacrylate copolymer), 1-11 pts. wt. linear polyolefin (C) of a MW of 100000-1000000, 0-1 pt. wt. fatty acid ester or its partial saponificate (D) (e.g., Na salt of montan wax ester), etc., and the obtained mixture is melt-kneaded.

Description

Detailed Description of the Invention <Industrial Application Field> The present invention has good moldability, excellent wire properties such as impact resistance and tensile strength, and is resistant to sliding with other types of resins and metal scraps. The present invention relates to a polyester sphere resin composition that can provide molded articles with excellent dynamic properties.

<Prior Art> Aromatic polyesters represented by polyethylene terephthalate and polybutylene terephthalate are used in a wide range of fields such as electrical and electronic equipment parts and automobile parts due to their excellent properties.

However, when aromatic polyester rubs against other types of resins or metals, it makes noise and wears out, causing a decline in operating performance. For such uses, it is already known to incorporate oil agents such as silicone and lubricants such as carboxylic acid metal salts (Japanese Patent Publication No. 47-32435, Japanese Unexamined Patent Publication No. 51-148744). It is also known that a similar effect can be achieved by combining with
1).

<The pinnacle of the invention's solution> We have found that it is effective to add olefins, which have almost no side chains, especially for sliding members. When molded, the polyolefin is liberated and adheres to the mold or precipitates on the surface of the molded product, resulting in cloudiness and significantly deteriorating the appearance of the molded product. As a result of intensive study by the present inventors,
By adding a glycidyl group-containing copolymer consisting of an α-olefin and a glycidyl ester of an α,β-unsaturated acid to an aromatic polyester and an olefin, or by further adding a fatty acid ester or a fatty acid ester to the above composition. The present invention was achieved by discovering an easily slippery polyester resin composition containing a partially saponified product, which provides an excellent molded product surface.

Means for Solving the Problems〉 That is, the present invention provides glycidyl group-containing copolymer 1-11 consisting of glycidyl ester of α-olefin and α,β-unsaturated acid based on 100 parts by weight of aromatic polyester.
An easily slippery polyester composition containing 1-11 parts by weight of a linear polyolefin having a molecular weight of 10,000 to 1,000,000 and (Q fatty acid ester, O-1 part by weight of a partially saponified product of a fatty acid ester) This is what we provide.

The aromatic polyester used in the present invention is a polyester having an aromatic ring in the chain unit of the polymer, and whose main components are an aromatic dicarboxylic acid (or its ester-forming derivative) and a diol (or its ester-forming derivative). It is a polymer or copolymer obtained by a condensation reaction.

The aromatic dicarboxylic acids mentioned here include terephthalic acid,
Isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, l,5-naphthalenedicarboxylic acid, bis(p-carboxyphenyl)methane, anthracenedicarboxylic acid, 4,4'-diphenyldicarboxylic acid, 4+ 4'
Examples include 7 phenyl ether dicarboxylic acid or its ester-forming derivatives.

In addition, if the acid component is 40 mol% or less, aliphatic dicarboxylic acids such as adipic acid, sebacic acid, azelaic acid, dodecanedioic acid, 1.3-7 chlorohexane dicarboxylic acid, 4-cyclohexane dicarboxylic acid, etc. may be substituted with dicarboxylic acids other than aromatic dicarboxylic acids, such as alicyclic dicarboxylic acids and their ester-forming derivatives.

In addition, the diol component includes aliphatic diols having 2 to 10 carbon atoms, such as ethylene glycol, propylene glycol, 1,4-butanediol, neopentyl glycol, 1,5-bentanediol, 1,6-hexanediol, and tecamethylene. Glycol, cyclohexanediol, etc. or molecules! 400-6,000 long chain glycols, i.e. polyethylene glycol, poly-1,
Examples include 3-propylene glycol, polytetramethylene glycol, and mixtures thereof.

Examples of preferable aromatic polyesters used in the present invention include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate, polycyclohexylene dimethylene terephthalate, polyethylene-2,6-naphthalate, etc. However, polybutylene terephthalate, which has appropriate mechanical strength, is most preferred.

Further, it is preferable that these aromatic polyesters have a relative viscosity in the range of 12 to 18 when a 0.5% orthochlorophenol solution is measured at 25°C. When the relative viscosity of the aromatic polyester is less than L2, sufficient mechanical strength cannot be obtained, and when it is 1.8 or more, a molded product with good surface gloss cannot be obtained, which is not preferable.

The α-olefin in the glycidyl group-containing copolymer comprising a α-olefin and a glycidyl ester of an α,β-unsaturated acid used in the present invention is ethylene, propylene, butene-1, etc., and ethylene is preferably used. . Furthermore, the glycidyl ester of an α,β-unsaturated acid has the general formula (wherein R is a hydrogen atom, a lower alkyl group, or a lower alkyl group substituted with a glycidyl ester group).
Specifically, glycidyl acrylate, glycidyl methacrylate, glycidyl ethacrylate, glycidyl itaconate, etc. Among them, glycidyl methacrylate is preferably used.Glycidyl group-containing copolymer The amount of copolymerized glycidyl ester of α,β-unsaturated acid in is 1 to 50% by weight, especially 2 to 30% by weight.
A range of weight percent is suitable. In addition, if the amount is 40% by weight or less, unsaturated monomers copolymerizable with the above copolymers, such as vinyl ethers, vinyl esters such as vinyl acetate and vinyl propionate, and acrylic acids such as methyl, ethyl, propyl, butyl, etc. Also, one or more types of methacrylic acid esters, acrylonitrile, styrene, carbon oxide, etc. may be copolymerized.

Preferred examples of the glycidyl group-containing copolymer in the present invention include ethylene/glycidyl methacrylate copolymer, ethylene/vinyl acetate/glycidyl methacrylate copolymer, ethylene/carbon oxide/glycidyl methacrylate copolymer, Examples include ethylene/glycidyl acrylate copolymer, ethylene/glycidyl acrylate/vinyl acetate copolymer, and the like.

In the present invention, the amount of (4) glycidyl group-containing copolymer added is 1-11 parts by weight per 100 parts by weight of aromatic polyester.
parts by weight, preferably 2 to 5 parts by weight. If the amount added is less than 1 part by weight, the impact properties will not be improved sufficiently, and if it is more than 11 parts by weight, the melt viscosity will increase and cause trouble during molding, so both are not preferred.

Next, the linear olefin (used in the present invention) is an olefin having a molecular weight of 100,000 to 1,000,000 and has substantially no side chains.

So-called high-pressure polyethylene with many side chains or polyolefin with a molecular weight of 1 million or more do not exhibit good sliding properties.

Moreover, if the molecular weight is less than 10,000, it will precipitate on the surface of the molded product and the surface appearance will deteriorate. A preferred linear polyolefin is polyethylene with a molecular weight of 300,000 to 400,000, and the amount added is 1 to 11 parts by weight, preferably 2 to 5 parts by weight, per 100 parts by weight of the aromatic polyester.

Addition amount: If it is less than 1 part by weight, the improvement in sliding properties will not be sufficient, and if it is more than 11 parts by weight, it will cause trouble when melting and mixing, which is not preferable.

Next, the fatty acid ester (C) that can be used in the present invention is an ester obtained from a -hydric or polyhydric alcohol and a saturated or unsaturated fatty acid, and specifically, methyl alcohol, ethyl alcohol, flobyl alcohol, Alcohols such as ethylene glycol, propylene glycol, tetramethylene glycol, decamethylene glycol, pentaerythritol, and glycerin, and capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, montanic acid, melisic acid, linoleic acid, and lylunic acid. , esters obtained from saturated or unsaturated fatty acids such as tetracosenoic acid, and partially saponified fatty acid esters are those obtained by partially saponifying fatty acid esters with alkali metals or alkaline earth metals. be.

The amount added is suitably 1 part by weight or less, and preferably 0.1 to 0.3 parts by weight, per 100 parts by weight of polyester. If it is more than 1 part by weight, it is not preferable because it may cause trouble during melt-kneading.

Incidentally, when a compound that promotes the reaction between the epoxy compound and the carboxylic acid is further added to the composition of the present invention, it is possible to obtain the effect that the impact resistance can be further improved. These compounds include triphenylamine, 2,4.
Tertiary amines such as 6-tris(dimethylaminomethyl)phenol, phosphite esters such as triphenylphosphite and triisodecylphosphite, tonophosphonium compounds such as triphenylallylphosphonium bromide, and tertiary phosphines such as triphenylphosphine. , carboxylic acid metal salts such as lithium stearate and calcium stearate, dodecylbenzenesulfonic acid) I
Jram, sulfonic acid metal salts such as sodium 3,5-cycarbomethoxybenzenesulfonate, sulfuric acid ester salts such as sodium lauryl sulfate, etc., and are added in an amount of 0.001 to 5 parts by weight per 100 parts by weight of polyester. It is preferable to

In contrast, the composition of the present invention may contain fibrous and granular fillers and reinforcing agents, antioxidants, and heat stabilizers (such as hindered phenols, hydroquinones, thioethers, phosphors, etc.) to the extent that the objects of the present invention are not impaired. UV absorbers (e.g., various resorcinols, salicylates, benzotriazoles, benzophenones, etc.), dyes (e.g., nitrosine), and pigments (e.g., cadmium sulfide,
phthalocyanine, carbon blank, etc.), flame retardants (e.g. decabromodiphenyl ether, halogen-based such as brominated polycarbonate, melamine or anuric acid-based, phosphorus-based, etc.), flame retardant aids (e.g. antimony oxide, etc.), One or more conventional additives such as antistatic agents (eg, sodium tif dodecylbenzenesulfonate, polyalkylene glycol, etc.), crystallization promoters, etc. can be added. Also small amounts of other thermoplastics (e.g. acrylics, fluororesins, polyamides,
Adding polyaceter (polycarbonate, polysulfone, polyphenylene oxide, etc.), thermosetting resin (e.g. phenol resin, melamine resin, epoxy resin, etc.), soft thermoplastic resin (e.g. ethylene/vinyl acetate copolymer, polyester elastomer, etc.) These resins may be used alone or in combination of two or more.

The method for producing the composition of the present invention is not particularly limited, but preferably the aromatic polyester, the glycidyl group-containing copolymer, the polyolefin and, if necessary, the fatty acid ester or the surrounding components are produced using an extruder. An example is a method of melt-kneading.

The resin composition of the present invention can be easily molded by conventional methods such as injection molding and extrusion molding, and the resulting molded product exhibits excellent properties.

<Example> The effects of the present invention will be explained in further detail with reference to Examples below.

Examples 1-4, Comparative Examples 1-4 Polybutylene terephthalate 100 with a relative viscosity of 1.62
Glycidyl group-containing copolymers, olefins, and saponified fatty acid esters in the types and proportions shown in Table 1 based on parts by weight were mixed in a single-screw extruder (5E-6 manufactured by Toshiba Machine Co., Ltd.) set at 250°C.
5) was kneaded and pelletized, and then a 5-ounce screw in-line injection molding machine set at 250°C was used to create a square plate of 1OαX IOOx 91 contact area 2. The cylinder made by the load 4. Ocd1 rotation speed 5 m/
Measure the dynamic friction coefficient in the mix and more! 005h
The surface of the molded product after ot molding was observed. Table 1 shows the test results.
Shown below. The coefficient of friction is reduced by adding olefins. In particular, the difference is remarkable when evaluated using the maximum value of the friction coefficient. Furthermore, when a saponified fatty acid ester is added, the friction coefficient further decreases.

However, if the copolymer does not contain a glycidyl group-containing copolymer, the surface condition of the molded product will be extremely poor.

As is clear from the results in Table 1, it can be seen that the molded articles made of the composition of the present invention have good sliding properties and the surface condition of the molded articles is good.

<Effects of the Invention> The polyester resin composition of the present invention has good sliding properties and can provide a molded article with a good surface condition.

Patent application Daitoshi Co., Ltd.

Claims (1)

[Claims] (A) 1 to 11 parts by weight of a glycidyl group-containing copolymer consisting of an α-olefin and a glycidyl ester of an α,β-unsaturated acid, (B) based on 100 parts by weight of the aromatic polyester;
Linear polyolefin 1 to 1 with a molecular weight of 100,000 to 1 million
1 part by weight and (C) 0 to 1 part by weight of a fatty acid ester or a partially saponified fatty acid ester.