JPH0562903B2 - - Google Patents

Description

[Detailed description of the invention]

<Industrial Application Field> The present invention relates to an aromatic polyester composition that not only has excellent hydrolysis resistance and molding fluidity, but also has good weather resistance. <Prior Art> Aromatic polyester resins represented by polybutylene terephthalate and polyethylene terephthalate are now being used in a wide range of fields due to their excellent chemical, physical, and mechanical properties. However, since these resins have ester bonds in their main chains, they have the disadvantage of poor stability against water, that is, poor hydrolysis resistance, which limits their use in the presence of moisture. This is the current situation. In order to improve the hydrolysis resistance of such aromatic polyesters, a wide range of studies have been conducted, including methods of adding epoxy compounds, typified by bisphenol-A diglycidyl ether, to aromatic polyesters. However, even when such an epoxy compound is added, the effect of improving hydrolysis resistance is not sufficient.
As shown in Publication No. 161452, attempts have been made to use bisphenol-A diglycidyl ether and various carbodiimide compounds in combination. <Problems to be solved by the invention> However, when the hydrolysis resistance of aromatic polyester is improved by the above method, there are problems such as a significant decrease in the fluidity of the resin during molding retention. However, no method for improving the hydrolysis resistance of aromatic polyesters has yet been found. <Means for Solving the Problems> Therefore, the present inventors conducted intensive studies to obtain an aromatic polyester composition that satisfies both hydrolysis resistance and molding fluidity at the same time. When a hindered phenol compound and/or a sulfur-containing ester compound are added to aromatic polyester in combination, not only the above objectives are achieved, but surprisingly, the weather resistance of aromatic polyester is also significantly improved. We have found that this can be improved, and have arrived at the present invention. That is, the present invention provides (A) an epoxy compound represented by the following general formula () based on 100 parts by weight of aromatic polyester (B)
0.01-10 parts by weight (However, in the formula, Ar represents an aromatic group or alicyclic group having 6 to 20 carbon atoms, and n represents an integer of 0 or 1 to 20.) (C) Hindered phenol compound and/or sulfur-containing compound At least one ester compound
The present invention provides an aromatic polyester composition containing 0.01 to 5 parts by weight. The aromatic polyester (A) used in the present invention is a polyester having an aromatic ring in the chain unit of the polymer, and is composed of 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 polycondensation reaction containing as a main component. The aromatic dicarboxylic acids mentioned here include terephthalic acid, isophthalic acid, orthophthalic acid, 1,
5-naphthalene dicarboxylic acid, 2,5-naphthalene dicarboxylic acid, 2,6-naphthalene dicarboxylic acid, 2,2'-biphenyldicarboxylic acid, 3,3'-
Biphenyldicarboxylic acid, 4,4'-biphenyldicarboxylic acid, 4,4'-diphenyl etherdicarboxylic acid, 4,4'-diphenylmethanedicarboxylic acid, 4,4'-diphenylsulfondicarboxylic acid, 4 , 4'-diphenylisopropylidene dicarboxylic acid, 1,2-bis(phenoxy)ethane-
4,4'-dicarboxylic acid, 2,5-anthracenedicarboxylic acid, 2,6-anthracenedicarboxylic acid, 4,4'-p-terphenylenedicarboxylic acid,
These include 2,5-pyridinedicarboxylic acid, and terephthalic acid is preferably used. Two or more of these aromatic dicarboxylic acids may be used in combination. In addition, in small amounts, adipic acid,
A mixture of one or more types of aliphatic dicarboxylic acids such as azelaic acid, dodecanedioic acid, and sebacic acid, and alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid can be used. In addition, as diol components, ethylene glycol, propylene glycol, butylene glycol, hexylene glycol, neopentyl glycol, 2-methyl-1,3-propanediol,
Examples include aliphatic diols such as diethylene glycol and triethylene glycol, alicyclic diols such as 1,4-cyclohexanedimethanol, and mixtures thereof. If the amount is small, one or more long-chain diols having a molecular weight of 400 to 6,000, such as polyethylene glycol, poly-1,3-propylene glycol, and polytetramethylene glycol, may be copolymerized. Specific aromatic polyesters include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate,
In addition to polyethylene-1,2-bis(phenoxy)ethane-4,4'-dicarboxylate, copolymerized polyesters such as polyethylene isophthalate/terephthalate, polybutylene terephthalate/isophthalate, polybutylene terephthalate/decanedicarboxylate, etc. can be mentioned.
Among these, polybutylene terephthalate and polyethylene terephthalate, which have well-balanced mechanical properties and moldability, can be preferably used. The aromatic polyester used in the present invention has a relative viscosity of 1.15 to 2.0, particularly 1.3 to 1.85, measured at 25°C in a 0.5% o-chlorophenol solution.
Preferably. The epoxy compound (B) used in the present invention is represented by the above general formula (). A specific example of Ar in formula () is 1,4-
Phenylene, 1,3-phenylene, 1,2-phenylene, 2-methyl-1,4-phenylene, 4,
4′-biphenylene, 3,3′-biphenylene, 2,
2'-biphenylene, 3,4'-biphenylene, 1,
4-naphthylene, 1,5-naphthylene, 2,6-
Naphthylene, 2,7-naphthylene, 1,4-cyclohexylene, 1,3-cyclohexylene, 1,
Preferred examples include 2-cyclohexylene, 4,4'-bicyclohexylene, and 2,6-decahydronaphthylene, among which 1,4-phenylene,
Particularly preferred are 1,3-phenylene and 2,6-naphthylene. The value of the degree of polymerization n of the compound of formula () is 0 or an integer of 1 to 20, preferably 0 or an integer of 1 to 10, and may be a mixture of compounds having various degrees of polymerization. Particularly preferred are those whose average degree of polymerization is in the range of 0 to 2 and the ratio of weight average molecular weight (Mw) to number average molecular weight (Mn), Mw/Mn, is in the range of 1.00 to 3.0. The method for producing the epoxy compound represented by the formula () is not particularly limited, but for example, a hydroxycarboxylic acid and an epihalohydrin are mixed at 40°C in the presence of a catalyst such as a quaternary ammonium salt, a tertiary amine, or a tertiary phosphine. An example of a manufacturing method is to perform halohydrin ester etherification by reacting at ~150°C, and then add an alkali metal salt to dehydrohalogenate. A product with a high degree of polymerization can be obtained by further reacting a hydroxycarboxylic acid in the presence of a catalyst while changing the ratio. In the present invention, the amount of the epoxy compound represented by the formula () added is 0.01 to 10 parts by weight, preferably 0.05 to 5 parts by weight, per 100 parts by weight of the aromatic polyester.
It is desirable that the amount is 0.2 to 3 parts by weight, more preferably 0.2 to 3 parts by weight. If the amount added is less than 0.01 parts by weight, the effect of improving the hydrolysis resistance of aromatic polyester will not be sufficient, while if it exceeds 10 parts by weight,
Both are unfavorable because they impair the mechanical properties of the aromatic polyester. Among component (C) used in the present invention, hindered phenol compounds include those having a structural unit represented by the following formula (). (In the formula, R is methyl, ethyl, propyl, t-
It is an alkyl group having 1 to 10 carbon atoms such as butyl. ) Those having the structural unit () preferably have a molecular weight of 500 or more, and specifically include the following compounds. Triethylene glycol-bis-3-(3'-t-butyl-
4'-hydroxy-5-methylphenyl)propionate, 1,3,5-tris(3',5'-di-t-
Butyl-4'-hydroxybenzoyl)isocyanurate, 1,3,5-trimethyl-2,4,6-
Tris(3',5'-di-t-butyl-4'-hydroxybenzyl)benzene, hexamethylene glycol-bis[β-(3,5-di-t-butyl-4-
Hydroxy-phenyl)propionate], 6-
(4'-hydroxy-3',5'-di-t-butylanilino)-2,4-bis-octyl-thio-1,3,
5-triazine, tetrakis [methylene-3(3',
5'-di-t-butyl-4'-hydroxy-phenyl)propionate]methane, 2,2'-thio[diethyl-bis-3-(3'',5''-di-t-butyl-
4″-Hydroxyphenyl)propionate], n
-octadecyl-3-(4'-hydroxy-3',5'-
di-t-butylphenol) propionate,
N,N'-hexamethylene-bis-3-(3',5'-
di-t-butyl-hydroxy-propamide), 1,
3,5-tris(3',5'-di-t-butyl-4'-
hydroxybenzyl) isocyanurate, 3,5
-di-t-butyl-4-hydroxy-benzyl phosphoric acid dimethyl ester, bis(3,5-di-t-butyl-4-hydroxy-benzyl phosphoric acid) monomethyl ester nickel salt, etc. n-octadecyl-3-(4'-hydroxy-3',5'-di-t-butylphenol)propionate, tetrakis[methylene-3-(3',5'-di-t-butyl-4'-hydroxy -phenyl)propionate]methane, triethylene glycol-bis-3-(3'-t-butyl-4'-hydroxy-5-methylphenyl)propionate, and the like can be preferably used. Among component (C) used in the present invention, the sulfur-containing ester compound is an ester compound having at least one sulfur atom in the molecule, and specifically,
Those having the structure of the following general formula () or () are preferable. S(−R′COOR″) ₂ () (R″SR′COOCH ₂ )− ₄ C () (In the formula, R′ is an alkylene group having 1 to 10 carbon atoms, and R″ is an alkylene group having 3 to 40 carbon atoms. ) Preferred examples of R' include methylene group, ethylene group, propylene group, butylene group, hexylene group, etc., and preferred examples of R'' include
Examples include octyl group, decyl group, tridecyl group, dodecyl group, myristyl group, and stearyl group. Specific examples of these sulfur-containing ester compounds include dioctylthiodipropionate, didodecylthiodipropionate, dodecylstearylthiodipropionate, distearylthiodipropionate, dimyristylthiodipropionate, didecyl Thiodipropionate, didodecyl-β,β′-thiodibutyrate, distearyl-
β,β′-thiodibutyrate, pentaerythritol-tetrakis (dodecylthiopropionate),
Pentaerythritol-tetrakis (dodecylthioacetate), Pentaerythritol-tetrakis (dodecylthiobutyrate), Pentaerythritol-tetrakis (octadecylthipropionate)
Examples include. Among these, didodecylthiodipropionate, distearylthiodipropionate, distearyl-β,β'-thiodibutyrate, and pentaerythol-tetrakis (dodecylthiopropionate) are preferred. In the present invention, the added amount of the hindered phenol compound and the sulfur-containing ester compound as component (C) is 0.01 to 5 parts by weight, preferably 0.05 to 5 parts by weight, either alone or in total, based on 100 parts by weight of the aromatic polyester. 3 parts by weight, more preferably 0.05~
The amount is preferably 1 part by weight. If the amount added is less than 0.01 part by weight, the effect of improving the hydrolysis resistance and weather resistance of the aromatic polyester will not be sufficient.
On the other hand, if the amount exceeds 5 parts by weight, the mechanical properties of the aromatic polyester will be impaired, which is not preferable. The feature of the present invention is that only when both the above-mentioned epoxy compound and hindered phenol compound and/or sulfur-containing ester compound are used in combination, it not only has excellent hydrolysis resistance and molding fluidity, but also has high weather resistance. The purpose is to provide a composition. In other words, if the epoxy compound of formula () is not used, or if the epoxy compound is used but is other than the epoxy compound of formula (), there will be problems with hydrolysis resistance and/or molding fluidity. However, when a hindered phenol compound and/or a sulfur-containing ester compound is used in combination, the hydrolysis resistance and weather resistance are further improved compared to when the epoxy compound of formula () is used alone. do. Although not particularly essential, by further adding fibrous and/or granular fillers to the composition of the present invention, the rigidity can be significantly improved without impairing other physical properties. Such fillers include glass fibers, carbon fibers, metal fibers, aramid fibers, asbestos, potassium titanate whiskers, wollastenite, glass flakes,
Examples include glass beads, talc, mica, clay, calcium carbonate, barium sulfate, titanium oxide, and aluminum oxide, among which chopped strand type glass fibers are preferably used. These addition amounts are usually aromatic polyester
It is preferable to use 120 parts by weight or less per 100 parts by weight. Furthermore, the composition of the present invention may contain conventional additives such as antioxidants, heat stabilizers, ultraviolet absorbers, lubricants, mold release agents, colorants including dyes and pigments, and nucleating agents, to the extent that the purpose of the present invention is not impaired. One or more types of additives can be added. Also small amounts of thermoplastic resins (e.g. polyphenylene oxide, polycarbonate, polyamide, polypropylene, polyethylene, ethylene/
Propylene copolymer, ethylene/butene-1 copolymer, ethylene/propylene/non-conjugated diene copolymer, ethylene/ethyl acrylate copolymer, ethylene/glycidyl methacrylate copolymer, ethylene/vinyl acetate/methacrylic acid (glycidyl copolymer, ethylene/propylene-g-maleic anhydride copolymer, etc.) can also be added. The method for producing the composition of the present invention is not particularly limited, but preferably, an aromatic polyester, an epoxy compound, a hindered phenol compound, and/or a sulfur-containing ester compound are mixed using an extruder. Examples include a method of melt-mixing, and a method of adding the three components at the final stage of polymerization of the aromatic polyester. When adding inorganic fillers and other additives, it is preferable to melt-knead them together with the above three using an extruder. 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 performance. <Example> The effects of the present invention will be explained in further detail with reference to Examples below. Parts in the examples indicate parts by weight. Examples 1 to 5, Comparative Examples 1 to 6 Polybutylene terephthalate with a relative viscosity of 1.75
For 100 parts, mix the amounts listed in Table 1 of the following epoxy compounds, hindered phenol compounds and/or sulfur-containing ester compounds (A) to (F) in a V blender, then use a 30 mmφ twin screw extruder. ,250℃
The mixture was melt-kneaded and pelletized. After drying the pellets at 130°C for 5 hours, they were molded using a 5-ounce screw-in-line injection molding machine set at 250°C, with a mold temperature of 80°C and a molding cycle (injection time/cooling time/intermediate time) of 15 seconds/ Formed in 20 seconds/10 seconds to obtain ASTM No. 1 dumbbells, and
The minimum molding pressure (gauge pressure), which is the minimum pressure required to fill the mold with resin, was measured. Regarding the obtained ASTM No. 1 dumbbell, 100℃
A 15-day hot water test was carried out using a Sunshine Weather-Ometer, with an arc current of 50 A and an arc voltage of 80 V, rainfall of 12 minutes/cycle of 60 minutes, and room temperature.
Treatment was carried out at 90°C for 40 days. For each obtained specimen, ASTM
A tensile test was conducted according to D-638. The above results are shown in Table 1. [List of additives] A: B: C: D: _{E :} S _{( -CH2CH2COOC12H25} ) _{-2F : ( - H25C12SCH2CH2COOCH2 ) -4C}

【table】

[Table] As is clear from the results in Table 1, when a specific epoxy compound and a group of hindered phenol compounds and/or sulfur-containing ester compounds are added together to aromatic polyester, the hydrolysis resistance It can be seen that an aromatic polyester composition not only has excellent molding fluidity but also has no deterioration in mechanical properties even when subjected to weatherometer treatment. In contrast, in the case where only the epoxy compound is added and the hindered phenol compound and the sulfur-containing ester compound are not added (Comparative Example 1), and when the hindered phenol compound and the sulfur-containing ester compound are added, the epoxy compound of the present invention When the amount of addition is small (Comparative Examples 2 to 4),
Mechanical properties deteriorate significantly during hot water treatment and weatherometer treatment. Furthermore, when an epoxy compound other than the epoxy compound of the present invention is used (Comparative Examples 5 and 6), not only there is a problem in molding fluidity but also the effect of improving hydrolysis resistance and weather resistance is small. Examples 6-9, Comparative Examples 7-10 Polybutylene terephthalate with a relative viscosity of 1.45
For 100 parts, use the amounts listed in Table 2 of 20 parts of glass fiber (3 mm long chopped strand type), epoxy compound, hindered phenol compound and/or sulfur-containing ester compound (A) to (F). hand,
Extrusion, molding, and physical property evaluation were performed in the same manner as in Example 1. From the results in Table 2, even when glass fiber is added, the composition of the present invention not only has excellent hydrolysis resistance and molding fluidity, but also shows no decrease in mechanical properties when subjected to hot water treatment and weatherometer treatment. It can be seen that an extremely small aromatic polyester composition is obtained. <Effects of the Invention> The aromatic polyester composition of the present invention not only has excellent hydrolysis resistance and molding fluidity, but also has good weather resistance, so it can be used under high temperature and humidity conditions, or when exposed to sunlight, wind and rain. used in places,
It is useful as mechanical parts, automobile parts, etc.

Claims (1)

[Claims] 1 (A) Based on 100 parts by weight of aromatic polyester (B) An epoxy compound represented by the following general formula ()
0.01-10 parts by weight (However, in the formula, Ar represents an aromatic group or alicyclic group having 6 to 20 carbon atoms, and n represents an integer of 0 or 1 to 20.) (C) Hindered phenol compound and/or sulfur-containing compound At least one ester compound
An aromatic polyester composition containing 0.01 to 5 parts by weight.