JPH0118100B2 - - Google Patents

Description

[Detailed description of the invention]

<Industrial Application Field> The present invention can provide molded products that have good moldability, excellent mechanical properties such as impact resistance and tensile strength, and excellent sliding properties with other types of resins and metals. This invention relates to a polyester resin composition. <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 mix lubricants such as silicone and other oils and 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 it with (Japanese Patent Publication No. 1971-7181). <Problems to be solved by the invention> We have found that it is effective to add a polyolefin having a single composition with almost no side chains, especially as a sliding member, but aromatic polyester When molded by injection molding, the polyolefin is liberated and adheres to the mold or precipitates on the surface of the molded product, causing cloudiness and significantly worsening the appearance of the molded product. As a result of intensive studies, the present inventors found that linear polyolefins and fatty acids consisting of a single composition of glycidyl group-containing copolymers consisting of α-olefins and glycidyl esters of α,β-unsaturated acids, as well as aromatic polyesters. The inventors have discovered a slippery polyester resin composition containing a partially saponified product of an ester or a fatty acid ester, which provides an excellent surface of a molded article, and has arrived at the present invention. <Means for Solving the Problems> That is, the present invention provides glycidyl group-containing copolymer 1 consisting of (A) α-olefin and glycidyl ester of α,β-unsaturated acid based on 100 parts by weight of aromatic polyester. ~11 parts by weight (B) Linear polyolefin 1 consisting of a single composition with a molecular weight of 100,000 to 1 million
The present invention provides an easily slippery polyester composition containing 11 parts by weight and (C) fatty acid ester, 0.1 to 1 part by weight of a partially saponified product of fatty acid ester. 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-naphthalene dicarboxylic acid, 1,5-naphthalene dicarboxylic acid, bis(p-carboxyphenyl)methane, anthracene dicarboxylic acid, 4, Examples include 4'-diphenyl dicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, and ester-forming derivatives thereof. In addition, if the acid component is 40 mol% or less, aliphatic dicarboxylic acids such as adipic acid, sebacic acid, azelaic acid, and dodecanedioic acid, and fatty acids such as 1,3-cyclohexanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid. Dicarboxylic acids other than aromatic dicarboxylic acids, such as group dicarboxylic acids and their ester-forming derivatives, may be substituted. In addition, as the diol component, alicyclic diols having 2 to 10 carbon atoms, namely ethylene glycol, propylene glycol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, decamethylene Examples include glycol, cyclohexanediol, etc., long chain glycols with a molecular weight of 400 to 6000, ie, polyethylene glycol, poly-1,3-propylene glycol, polytetramethylene glycol, etc., and mixtures thereof. Examples of preferred aromatic polyesters used in the present invention include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate,
Examples include polycyclohexylene dimethylene terephthalate and polyethylene-2,6-naphthalate, among which polybutylene terephthalate, which has appropriate mechanical strength, is most preferred. Further, these aromatic polyesters preferably have a relative viscosity in the range of 1.2 to 1.8 when a 0.5% orthochlorophenol solution is measured at 25°C. If the relative viscosity of the aromatic polyester is less than 1.2, sufficient mechanical strength cannot be obtained, and if it is 1.8 or more, a molded product with good surface gloss cannot be obtained, which is not preferred. The α-olefin in the glycidyl group-containing copolymer (A) consisting of an 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 preferable. Can be used. Also,
Glycidyl esters of α,β-unsaturated acids have the general formula (In the formula, 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, These include glycidyl itaconate, among which glycidyl methacrylate is preferably used. The copolymerized amount of glycidyl ester of α,β-unsaturated acid in the glycidyl group-containing copolymer is suitably in the range of 1 to 50% by weight, particularly 2 to 30% by weight. Also, an additional 40% by weight
Unsaturated monomers copolymerizable with the above copolymers, such as vinyl ethers, vinyl esters such as vinyl acetate and vinyl propionate, acrylic acid and methacrylic acid esters such as methyl, ethyl, propyl, and butyl, as long as the following: One or more types of acrylonitrile, styrene, carbon monoxide, etc. may be copolymerized. Preferred examples of the glycidyl group-containing copolymer (A) in the present invention include ethylene/glycidyl methacrylate copolymer, ethylene/vinyl acetate/glycidyl methacrylate copolymer, and ethylene/carbon monoxide/glycidyl methacrylate copolymer. Coalescence, ethylene/glycidyl acrylate copolymer, ethylene/
Examples include glycidyl acrylate/vinyl acetate copolymer. In the present invention, the amount of glycidyl group-containing copolymer (A) added is 1 to 11 parts by weight, preferably 2 to 5 parts by weight, per 100 parts by weight of the aromatic polyester.
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 polyolefin (B) used in the present invention is a polyolefin having a single composition having a molecular weight of 100,000 to 1,000,000 and having 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. Furthermore, if the molecular weight is less than 100,000, it will precipitate on the surface of the molded product and the surface appearance will deteriorate. A preferred linear polyolefin with a single composition has a molecular weight of 300,000 to 40.
The amount added is 1 to 11 parts by weight, preferably 2 to 5 parts by weight, per 100 parts by weight of aromatic polyester. If the amount added is less than 1 part by weight, the sliding properties will not be improved sufficiently, and if it is more than 11 parts by weight, it will cause trouble during melt-kneading, which is not preferable. Next, the fatty acid ester (C) that can be used in the present invention is an ester obtained from a monohydric or polyhydric alcohol and a saturated or unsaturated fatty acid,
Specifically, methyl alcohol, ethyl alcohol, propyl alcohol, ethylene glycol,
Alcohols such as propylene glycol, tetramethylene glycol, decamethylene glycol, pentaerythritol, glycerin, capric acid, lauric acid, myristic acid, valmitic acid,
Esters obtained from saturated or unsaturated fatty acids such as stearic acid, montanic acid, melisic acid, linoleic acid, linolenic acid, and tetracosenoic acid, and partially saponified fatty acid esters are
It is obtained by partially saponifying a fatty acid ester as described above with an alkali metal or an alkaline earth metal. The amount added is 0.1 to 100 parts by weight of polyester.
1 part by weight, preferably 0.1 to 0.3 parts by weight. 1
If the amount exceeds 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 tertiary amines such as triphenylamine and 2,4,6-tris(dimethylaminomethyl)phenol;
Phosphite esters such as triphenylphosphite and triisodecylphosphite, phosphonium compounds such as triphenylallylphosphonium bromide, tertiary phosphines such as triphenylphosphine, carboxylic acid metal salts such as lithium stearate and calcium stearate, Examples include sulfonic acid metal salts such as sodium dodecylbenzenesulfonate and sodium 3,5-dicarbomethoxybenzenesulfonate, and sulfuric acid ester salts such as sodium lauryl sulfate.
It is preferable to add 0.001 to 5 parts by weight per 100 parts by weight. 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, phosphites, and UV absorbers (e.g., various resorcinols, salicylates, benzotriazoles, benzophenones, etc.), dyes (e.g., nitrosine), and pigments (e.g., cadmium sulfide, phthalocyanines, carbon black, etc.) Coloring agents, flame retardants (e.g. decabromodiphenyl ether, halogens such as brominated polycarbonate, melamine or cyanuric acid, phosphorus, etc.), flame retardant aids (e.g. antimony oxide), antistatic agents (e.g. dodecyl One or more conventional additives such as sodium benzenesulfonate, polyalkylene glycol, etc.), crystallization promoters, etc. can be added. Additionally, small amounts of other thermoplastic resins (e.g. acrylic resins, fluororesins, polyamides, polyacetals, polycarbonates,
polysulfone, polyphenylene oxide, etc.)
Thermosetting resins (e.g., phenol resins, melamine resins, epoxy resins, etc.) and soft thermoplastic resins (e.g., ethylene/vinyl acetate copolymers, polyester elastomers, etc.) can also be added, and only one type of these resins may be used. Alternatively, two or more types may be used in combination. The method for producing the composition of the present invention is not particularly limited, but preferably uses an extruder to produce the aromatic polyester, glycidyl group-containing copolymer, linear polyolefin consisting of a single composition, and fatty acid ester. An example of this method is to melt and knead the mixture. 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 1-3, Comparative Examples 1-4 Polybutylene terephthalate with a relative viscosity of 1.62
For 100 parts by weight, glycidyl group-containing copolymers, polyolefins, and saponified fatty acid esters of the types and proportions shown in Table 1 were kneaded and pelletized using a single-screw extruder (SE-65 manufactured by Toshiba Machine Co., Ltd.) set at 250°C. Then, using a 5oz screw in-line injection molding machine set at 250℃, 10cm x 10
Create a square plate of cm x 2mm ^t and use Noril “SE-90J”
The cylinder made using
cm ² and a rotation speed of 5 m/min, the dynamic friction coefficient was measured, and the molded surface after 100 shot molding was observed. The test results are shown in Table 1. The coefficient of friction is reduced by adding polyolefin. 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 of the compositions of the present invention have good sliding properties and the surface condition of the molded articles is good.

[Table] <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.

Claims (1)

[Claims] 1 (A) α based on 100 parts by weight of aromatic polyester
-Glycidyl group-containing copolymers 1 to 11 consisting of olefin and glycidyl ester of α,β-unsaturated acid
parts by weight, (B) 1 to 11 parts by weight of a linear polyolefin consisting of a single composition with a molecular weight of 100,000 to 1 million, and (C) 0.1 to 1 part by weight of a fatty acid ester or a partially saponified product of a fatty acid ester. Easy slippery polyester resin composition.