JPS62146949A - Polyethylene terephthalate molding composition - Google Patents

Abstract

PURPOSE:To provide the titled compsn. having excellent impact resistance, appearance, etc., by blending a polyethylene terephthalate resin prepd. by using a tin compd. or a Ti compd. as a polymn. reaction catalyst with an olefin copolymer having glycidyl groups. CONSTITUTION:A dicarboxylic acid component mainly composed of terephthalic acid is reacted with a diol component mainly composed of ethylene glycol in the presence of at least one member selected from tin compds. and titanium compds. (e.g., monobutyltin oxide, tetrabutyl titanate) as a polymn. catalyst to produce a thermoplastic polyester. 100pts.wt. thermoplastic polyester is blended with 0.5-80pts.wt. olefin copolymer having glycidyl groups (e.g., an ethylene/ glycidyl methacrylate copolymer) to obtain the desired polyethylene terephthalate molding resin compsn.

Description

Detailed Description of the Invention <Industrial Application Field> The present invention provides a polyethylene terephthalate composition for molding which has excellent mechanical properties such as impact resistance and surface appearance such as surface smoothness. It is related to

<Prior Art> Thermoplastic polyesters composed of aromatic dicarboxylic acid components and aliphatic or alicyclic diols are widely used as fibers and films.

Among them, polyethylene terephthalate has excellent heat resistance, rigidity, and surface properties.

However, compared to polybutylene terephthalate, it has a slow crystallization rate, is difficult to mold, and has poor impact resistance, making it unsuitable for use as engineering plastics.

Conventionally, to improve the impact resistance of polyethylene terephthalate, it has been proposed and implemented to use a large amount of reinforcing filler such as galanu fiber, but is it possible to strengthen it with filler? This certainly improves impact resistance, but
It has a major drawback in that most of the screter surface characteristics possessed by unreinforced polyethylene terephthalate, such as surface smoothness, surface slipperiness, surface appearance, flexibility, and fluidity, are lost. For this reason, polyethylene terephthalate reinforced with the above-mentioned reinforcing filler cannot be used in fields where these characteristics are important, such as automobile exterior parts and electrical and electronic external parts.

As a method for improving impact resistance, the present inventors have previously discovered a method (Japanese Patent Application Laid-open No. 32045/1983) of combining a saturated polyester and an olefin copolymer containing a glycidyl group.

On the other hand, in addition to antimony compounds, germanium compounds, tin compounds, and titanium compounds are known to be used as polymerization reaction catalysts for polyethylene terephthalate, but antimony compounds are industrially advantageous and common. .

<Problems to be Solved by the Invention> However, in the method of combining a saturated polyester and an olefin copolymer having a glycidyl group,
When polyethylene terephthalate produced by a normal production method is used as a saturated polyester, that is, a low polymer obtained by esterifying a terephthalic acid component and an ethylene glycol component by a transesterification method or a direct esterification method can be used as a polymerization reaction catalyst. When polyethylene terephthalate obtained by polymerizing an antimony compound to a predetermined degree of polymerization is used, it is industrially most advantageous, but it is not sufficiently effective in improving impact resistance due to the formation of gelled products. It has been found that this method has the drawbacks of not being able to obtain a smooth surface and lacking in surface smoothness.

The object of the present invention is to provide a polyethylene terephthalate resin composition that eliminates the above-mentioned drawbacks and allows molded products with excellent mechanical properties such as impact resistance and excellent surface appearance such as surface smoothness to be obtained. It is about providing something.

<Means for solving the problem> According to the studies of the present inventors, the present invention can be achieved by combining a thermoplastic polyester produced using a specific polymerization reaction catalyst and an olefin copolymer containing a glycidyl group. It has been found that the invention can solve the problem it seeks to solve.

That is, the present invention uses one or more selected from tin compounds and titanium compounds as a polymerization reaction catalyst in a thermoplastic polyester e consisting of a dicarboxylic acid component mainly consisting of a terephthalic acid component and a diol component mainly consisting of an ethylene glycol component. 0 parts by weight of the glycidyl group-containing olefin copolymer per 100 parts by weight of the thermoplastic polyester produced using
．． The present invention provides a polyethylene terephthalate composition for molding comprising 5 to 80 parts by weight of a bearing part.

As the tin compound used as a polymerization reaction catalyst in the present invention, alkyltin oxides such as mono-butyltin oxide and di-butyltin oxide are preferably used.

In addition, titanium compounds include tetraalkyl titanates,
Examples include titanium compounds such as titanyl oxalate salts, titanyl oxalate, and titanium tetrachloride, such as tetraethyl titanate, tetrapropyl titanate, tetrabutyl titanate, and their partial hydrolysates, titanyl ammonium oxalate, sodium titanyl oxalate, Potassium titanyl oxalate, calcium titanyl oxalate, titanyl n+-rontium oxalate, manganese titanyl oxalate, sodium titanate chloride, ammonium titanate fluoride, etc., and tetraethyl titanate and tetrabutyl titanate are preferably used.

These polymerization reaction catalysts may be used alone or in combination of two or more. The amount of these additions to polyester is
0.005 to 0.2% is preferable, especially 0.01 to 0.2%
o, ii Amount% is preferred.

Further, the addition time of these polymerization reaction catalysts may be any time as long as it is before the start of polymerization.

The dicarboxylic acid component mainly containing terephthalic acid component used in the present invention is terephthalic acid or its alkyl ester,
The main dicarboxylic acid component is an ester-forming derivative such as phenyl ester, and a portion (20 mol% or less) of it is used as isophthalic acid, orthophthalic acid, 2.6-naphthalenedicarboxylic acid, 5-naphthalenedicarboxylic acid, bis(
P-carboxyphenyl)methaneanthracenedicarboxylic acid, 4,4'-diphenyldicarboxylic acid, 1,2-bis(phenoxy)ethane-4,4'-dicarboxylic acid, 5
- Aromatic dicarboxylic acids such as sodium sulfoisophthalic acid, aliphatic dicarboxylic acids such as adipic acid, sepacic acid, azelaic acid, and dodecanedioic acid, and alicyclic acids such as 1,3-cyclohexanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid. It may be replaced with one or more of the formula dicarboxylic acids and their ester-forming derivatives.

The main diol component is ethylene glycol or its ester-forming component, and a portion (20 mol% or less) of the diol component is aliphatic glycol having an ash number of 2 to 20, i.e., ethylene glycol, cefropylene glycol, 1.4- Butanediol, neopentyl glycol, 1.5-bentanediol, 1.6-hexanediol, decamethylene glycol, cyclohexane dimetatool, cyclohexanediol, etc., and one or more of their ester-forming derivatives may be used instead. good.

The method for polymerizing the thermoplastic polyester comprising the dicarboxylic acid component and the diol component is not particularly limited, but for example, terephthalic acid and ethylene glycol may be directly esterified without a catalyst or in the presence of a catalyst (for example, a tin compound or a titanium compound). Alternatively, a low polymer is first prepared by transesterifying dimethyl terephthalate and ethylene glycol in the presence of a catalyst (such as a magnesium compound, zinc compound, cobalt compound, calcium compound, or manganese compound); A method of obtaining a thermoplastic polyester by adding a polymerization reaction catalyst consisting of one or more selected from tin compounds and titanium compounds and polymerizing under reduced pressure can be mentioned. Further, the timing of adding this polymerization reaction catalyst is not particularly limited, and may be added at any time before the polymerization reaction, or may be added directly before the esterification reaction or before the transesterification reaction.

In addition, when producing thermoplastic polyester, to improve the color tone of the polymer, phosphoric acid, phosphorous acid, hypophosphorous acid, and their furkylene ethers or aryl ethers, such as monomethyl phosphate, dimethyl phosphate, and trimethyl phosphate, are used. , methyldiethyl phosphate, triethyl phosphate,
Triisopropyl phosphate, tributyl phosphate, triphenyl phosphate, tribenzyl phosphate, tricyclohexyl phosphate, trinoflV sulfite, triethyl phosphite,
Tributymu phosphite, tri(δ-hydroxybutyl) phosphite, triphenyl phosphite, etc. Special phosphoric acid, phosphorous acid, trimethyl phosphate, trimethyl phosphite, etc. Table esterification reaction or ester It may be added after the chemical exchange reaction.

Further, it is preferable that the thermoplastic polyente P has a logarithmic viscosity of 0.36 to 140, particularly 0.52 to 1.18, when a 0.5% orthochlorophenol solution is measured at 25°C. If it is less than 0.36, it is difficult to obtain sufficient mechanical properties, and if it exceeds 1.40, it is difficult to obtain a molded product with good surface gloss.

The glycidyl group-containing olefin copolymer used in the present invention is a copolymer consisting of an α-olefin and a glycidyl ester of an a,β-unsaturated acid, and the α-olefin in the copolymer is ethylene, propylene, etc. , butene-1, etc., but ethylene is preferably used. In addition, glycidyl esters of α,β-unsaturated acids are compounds represented by the general formula (in the formula, R is a hydrogen atom or a lower alkyl group), and specifically, glycidyl acrylate, methacrylic acid These include glycidyl, glycidyl ethacrylate, and glycidyl methacrylate is preferably used. The amount of copolymerized glycidyl ether of α,β-unsaturated acid is suitably in the range of 0.5 to 50% by weight. Furthermore, unsaturated monomers that can be copolymerized with the above copolymers at 40% by weight or less, such as vinyl ethers, vinyl acetate, vinyl natonohinyl ethers propionate, acrylic acids such as methyl, ethyl, and propyl; Entels of methacrylic acid, acrylonitrile, styrene, etc. may be copolymerized.

Specific examples of olefin copolymers containing glycidyl groups include ethylene/glycidyl methacrylate copolymers and ethylene/glycidyl methacrylate/vinyl acetate copolymers. These can be used in combination of two or more types.

The glycidyl group-containing olefin copolymer is preferably used in an amount of 0.5 to 80 parts by weight, particularly 5 to 50 parts by weight, based on 100 parts by weight of the thermoplastic polyester.

When using a glycidyl group-containing olefin copolymer, organic sulfonic acid metal salts such as sodium dodecylbenzenesulfonate and sodium dodecylsulfonate, and sulfuric acid esters of alcohols such as sodium lauryl sulfate, etc. A better impact resistance improvement effect can be obtained by adding a small amount of /L/salt.

The composition of the present invention contains lithium,
sulphates, carbonates and oxides of sodium, magnesium, aluminum, calcium, zinc and barium;
Salts of the above metals with aliphatic carboxylic acids or aromatic carboxylic acids having an ash number of 1 to 36, salts of ethylene-α, β-unsaturated acid copolymers with the above metals, powdered clay minerals, etc. are effective. It can also be used.

Specific examples of these moldability improvers include barium sulfate, magnesium carbonate, calcium carbonate, aluminum oxide, zinc oxide, sodium stearate, and stearin 1.
Shun barium, epoxy IL- barium sinuteate, monomethyl sodium terephthalate, disodium terephthalate, isophthalate/l/
Preferred examples include monomethyl sinodium acid, disodium isophthalate, partially sodium-substituted ethylene-methacrylic acid copolymer, mica, talc, kaolin, and clay, with barium stearate being particularly preferred.

The amount of these moldability improvers added is the thermoplastic poly-1-;t
0.01 to 25 parts by weight to tez1/loo weight part C,
Particularly preferred is 0.05 to 10 parts by weight.

The composition of the present invention may also contain antioxidants, heat stabilizers (for example, hindered phenol, hydroquinone, phosphites, substituted products thereof, etc.), ultraviolet absorbers ( (e.g. resorcinol, salicylates, benzotriazoles, benzophenones, etc.), lubricants and mold release agents (e.g. montanic acid and its salts, esters, hafester, nutary μ alcohol, stearamide and polyethylene waxes, etc.), dyes (e.g. nitrosine, etc.) and pigments (e.g. cadmium sulfide,
Common additives such as colorants, flame retardants, plasticizers, antistatic agents, etc. (including phthalocyanine, carbon black, etc.)
More than one species may be added.

In addition, other thermoplastic resins, such as polyolefin resins such as polyethylene and polypropylene, modified polyolefin resins such as ethylene-vinyl acetate copolymers, borinutylene resins, ABS resins, polyamide resins, polyacetal resins, polyester μ resins other than those of the present invention, and polycarbonates. Resins, polyphenylene oxide, polysulfone, polyphenylene sulfide, polyarylate resins, etc. can be added.

As a method for producing the polyethylene terephthalate resin composition of the present invention, for example, as described above, a glycidyl group-containing olefin copolymer is added to polyethylene terephthalate using one or more selected from tin compounds and titanium compounds as a polycondensation catalyst. and other additives may be blended all at once, supplied to a screw extruder, and mixed by melt extrusion.

The resin composition of the present invention can be easily molded by conventional methods such as injection molding and extrusion molding, and molded articles having impact resistance and good color tone can be obtained.

The present invention will be explained below with reference to Examples.

<Example> Examples 1 to 6, Comparative Examples 1 to 7 Ethylene glycol in a molar amount 180 times that of dimethyl terephthalate was added and stirred, and then acetic acid was added as a transesterification reaction catalyst to 0.09% by weight of cobalt tetrahydrate was added, the temperature was gradually raised, and transesterification was carried out at normal pressure and 240 to 245°C to obtain a low polymer. To this, 10.02% by weight of trimethyl phosphate/L was added and stirred thoroughly, and then mono-n-butyltin oxide, tetrabutyl titanate or antimony trioxide was added as a polymerization reaction catalyst to the polyester to be produced, as shown in Table 1 e. Added in the indicated proportions. Next, pressure reduction and temperature increase were started, and the degree of vacuum reached 0.03 T approximately 50 minutes after the start of pressure reduction.
Orr.

After polymerization at a temperature of 280° C. for about 2 hours, the mixture was discharged into water to obtain polyethylene terephthalate chips having a logarithmic viscosity of 0.65.

To 100 parts by weight of the obtained polyethylene terephthalate chips, ethylene/glycidyl methacrylate copolymer (copolymerization weight ratio 88/12) and other additives shown in Table 1 were blended in the proportions shown in Table 1. Blend and
The mixture was melt-kneaded and pelletized in an extruder equipped with a 40 mm diameter screw set at 275°C. 2 of the obtained berets
It was subjected to an injection molding machine with a mold clamping pressure of 75 tons set at 80°C, and molded at a mold temperature of 130 to 150°C to meet ASTM D2.
An impact test piece with a specification of 56 f was obtained.

Then, using the obtained test piece, ASTM D256
Therefore, an impact test was conducted to evaluate the impact resistance.

These results are shown in Table 1.

Note that the surface smoothness of the obtained test pieces in Examples 1 to 6 was better than that in Comparative Examples 1 to 7.

161 Examples 7 to 8, Comparative Examples 8 to 16 15 times m/l'i of ethylene glycol was added to the terephthalic acid and stirred, and then monomer was added as a direct esterification catalyst to the amount of polyester produced. Butyltin oxide and tetrabutyl titanate were added in the proportions shown in Table 2, and the temperature was gradually raised to 245°C under N2 gas pressure.
This was directly esterified to obtain a low polymer. To this was added 0.02% of phosphoric acid and stirred well, and then monobutyltin oxide, tetrabutyl titanate or antimony trioxide as a polymerization reaction catalyst was added to the polymerization shown in Table 2. Then, pressure reduction and temperature increase were started, and about 50 minutes after the start of pressure reduction,
Approximately 2 minutes at a vacuum level of 0.03 Torr and a temperature of 280°C
After hr polymerization, the logarithmic viscosity was 0.6σ by discharging it underwater.
of polyethylene terephthalate was obtained. The same method as in Example 1 was followed by blending with ethylene/glycidyl copolymer.
Molding and evaluation were performed. The results are shown in Table 2.

Note that the surface smoothness of the obtained test pieces in Examples 7 to 8 was better than that in Comparative Examples 8 to 16.

As is clear from the results in Tables 1 and 2, the properties of molded articles obtained from the composition of the present invention are significantly superior in impact resistance compared to conventional products using antimony trioxide. .

<Effect of the invention> The present invention? This has made it possible to obtain a polyethylene terephthalate composition for molding that has excellent mechanical properties such as impact resistance and surface appearance such as surface smoothness.

Claims (1)

[Claims] Thermoplastic polyester 100, which is composed of a dicarboxylic acid component mainly consisting of a terephthalic acid component and a diol component mainly consisting of an ethylene glycol component, produced using one or more selected from tin compounds and titanium compounds as a polymerization reaction catalyst. A molding polyethylene terephthalate composition comprising 0.5 to 80 parts by weight of a glycidyl group-containing olefin copolymer.