JPS5842644A - Modified polyester composition for molding - Google Patents

Abstract

PURPOSE:To provide the titled compsn. having excellent crystallization characteristics and remarkably improved water absorption properties, by blending a polyoxyalkylene compd.-modified polyester, an ionizable metal salt of an org. compd. having an acidic proton, and a phenolic antioxidant with a polyester. CONSTITUTION:A polyester (A) modified with 0.1-50wt% polyoxyalkylene compd. of the formula (wherein R1 is H, an n-valent org. group; R2 is a 2-4C aliph. hydrocarbon group; 0.1<C2/C3+C4 (molar ratio)<1.0; R3 is H, a hydrocarbon org. group which may contain N, O, S, P or a metallic element; m, n are each a positive integer), 0-20wt% (based on the total amount of the compsn.) ionizable metal salt of an org. compd. (B) having an acidic proton, and 0-5wt% phenolic antioxidant (C), are blended with a polyester such as polyethylene terephthalate to obtain the titled compsn.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a modified polyester composition for molding which has excellent crystallization properties and significantly improved water absorption properties. Specifically, it relates to a modified polyester obtained by copolymerizing and/or mixing a specific polyoxyalkylene compound with a polyester, and further includes an ionizable metal salt of an organic compound having at least one acidic proton and a phenolic antioxidant. This composition has a wide crystallizable region, a rapid crystallization rate, significantly improved water absorption properties, good thermal oxidative stability, and is economically advantageous for molding. The present invention relates to a modified polyester composition for use.

High molecular weight linear polyesters obtained from dicarboxylic acids, mainly terephthalic acid, or their ester-forming derivatives, and diols or their ester-forming derivatives have a high softening point, and have excellent heat resistance, chemical resistance, and light resistance. It is widely used in fibers, films, and molded products because of its excellent electrical, physical, and mechanical properties. However, when such polyester is used as an injection molded article,
The crystallization rate is slow compared to the same crystalline polymers such as nylon and polyacetal, and in particular polyethylene terephthalate (polyethylene terephthalate), crystallization hardly progresses at temperatures below 100°C. It has been strongly desired to improve the crystallization properties of polyester, especially polyethylene terephthalate, to shorten the molding cycle, and to expand the mold temperature range during molding.

In order to improve the crystallization properties of polyethylene terephthalate, there is a method of blending or copolymerizing low-molecular or high-molecular compounds with plasticizing ability, such as ester compounds, aliphatic copolyesters, and polyoxyalkylene compounds. Among them, polyoxyalkylene compounds, particularly polyoxyethylene glycol or its derivatives, are now known as one of the soft segments with great plasticizing ability and crystallization promoting ability because of their excellent compatibility with polyethylene terephthalate.

However, polyoxyethylene compounds are hydrophilic and have the disadvantage of being extremely easy to absorb water. On the other hand, polyoxypropylene and polyoxytetramethylene compounds are hydrophobic except for low molecular weight compounds and do not absorb water easily, but their compatibility with polyethylene terephthalate is problematic, and therefore their crystallization properties are The improvement effect is smaller than that of polyoxyethine compounds. Furthermore, polyoxypropylene compounds are susceptible to thermal oxidative decomposition;
Polyoxytetramethylene has the disadvantage of high production economic costs.

In order to solve these problems, the present inventors have carried out extensive research, and have surprisingly discovered that it is possible to copolymerize and/or mix a specific polyoxyalkylene compound with polyester, and more advantageously, to achieve this composition. By incorporating an ionizable metal salt of an organic compound having at least one acidic proton and a phenolic antioxidant into the product, it has excellent crystallization properties, good thermal oxidation stability, and significantly improved water absorption properties. The inventors have discovered that a composition can be obtained, and have arrived at the present invention.

That is, the present invention is based on the general formula % formula % (wherein, R1 is hydrogen or an n-valent organic group, and R2 is a C2-
C4 aliphatic hydrocarbon group, and C2/C3+C
4 (Mo/L/ratio) 0.1 or more and less than 1.0, R3 is a hydrocarbon organic group that may contain nitrogen, oxygen, sulfur, phosphorus, or metal elements, or hydrogen; , n are positive integers. ) A modified polyester obtained by copolymerizing and/or mixing 0.1 to 50% by weight of a polyoxyalkylene compound represented by ionizable metal salt of an organic compound (6), 0 to 5% by weight of a phenolic antioxidant (Q
This is a modified polyester composition for molding.

The polyester referred to in the present invention is at least 80 mol%
A dicarboxylic acid component of up to terephthalic acid and at least 80 mol% of ethylene glycol, furopane-
After direct esterification or transesterification with the diol component which is 1+ 3-diol, butane-1,4-diol, pentane-1,5-diol, hexane-1,6-diol, cyclohexane-1,4-dimetatool. , obtained by polycondensation. Particularly preferred is polyethylene terephthalate, and more preferably polyethylene terephthalate having an intrinsic viscosity of 0.55 or more and less than 0.70. 0 to 20 mol% of the dicarboxylic acid component of the polyester is other aromatic dicarboxylic acid having 6 to 14 carbon atoms, aliphatic dicarboxylic acid having 4 to 8 carbon atoms, or alicyclic dicarboxylic acid having 8 to 12 carbon atoms; Good too. Examples of such dicarboxylic acids include phthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 4°4-diphenyldicarboxylic acid, adipic acid, cepacic acid, cyclohexanedicarboxylic acid, and the like.

Furthermore, 0 to 20 mol% of the diol component may be other aliphatic diols having 8 to 10 carbon atoms, other alicyclic diols having 6 to 15 carbon atoms, or aromatic diols having 6 to 12 carbon atoms. . Examples of such diols include 2,2-dimethylpropane-1°S-diol, 2,2-bis-(4
'-Hydroxycyclohexyl)-propane, 2,2-
Examples include bis-(4'-hydroxyphenyl)propane and hydroquinone. Furthermore, an oxycarboxylic acid such as ε-oxycaproic acid, hydroxybenzoic acid, etc. may be copolymerized in an amount of 20 mol % or less of the dicarboxylic acid component and diol component. Of course, the polyester is 3
It may be branched with a trihydric or tetrahydric alcohol, or a tribasic or tetrabasic acid. Examples of suitable branching agents include:
Examples include trinosinic acid, trimellitic acid, trimethylolpropane, pentaerythritol, and the like.

The specific polyoxyalkylene compound referred to in the present invention is
General formula % Formula % (However, R1 is hydrogen or an n-valent organic group, R2 is C2 ~
C4 aliphatic hydrocarbon group, and C2/C3+C
4 (molar ratio) is 0.1 or more and less than 1.0, and R3 is a hydrocarbon organic group containing nitrogen, oxygen, sulfur, phosphorus, or a metal element, or hydrogen.

n is a positive integer. ). Specific examples of such polyoxyalkylene compounds include polyoxyethylene propylene/tetramethylene glycol (random or block) derived from -functional alcohols, trifunctional alcohols, polyfunctional alcohols, and their - Methyl ether, glycidyl ether, phenyl ether, methyl ester, benzoic acid ester, phthalic acid ester, trimellitic acid ester, etc., and metal salts such as heptatalic acid ester and trimellitic acid ester are also preferably exemplified. . When using a polyoxyalkylene compound containing a metal salt, an especially excellent ability to promote crystallization is observed, and it also contributes to oxidative stability. does not necessarily require the use of ionizable metal salts or phenolic antioxidants. Of course, the specific polyoxyalkylene compound in the present invention is not limited to those exemplified above. These may be used alone or in combination of two or more.

The molecular weight range of such a specific polyoxyalkylene compound is preferably 200 to 100,000, particularly 700 to 5 d00 in view of the degree of compatibility with the polyester chain, the degree of water absorption improvement effect, and the physical properties of the resulting composition. The amount used is 0.1 to 50% by weight, particularly preferably 1 to 15% by weight, based on the polyester from the viewpoint of the level of crystallization promotion, mechanical strength, etc. Furthermore, from the viewpoint of uniform dispersion of the specific polyoxyalkylene compound in the present invention, it is particularly preferable that the specific polyoxyalkylene compound is copolymerized with polyester.

Copolymerization and/or mixing of such polyoxyalkylene compounds can be carried out by adding the polyoxyalkylene compound during the production of polyester and reacting or mixing it, mixing the polyester with a mixing device such as an extruder, or adding the polyoxyalkylene compound after mixing. This can be accomplished by a method such as a melt polycondensation reaction. Furthermore, it is also possible to subsequently subject the copolymer or mixture to a solid-phase polycondensation reaction.

Examples of the ionizable metal salt of an organic compound having at least one acidic proton according to the present invention include carboxylic acid, hydroxycarboxylic acid, sulfonic acid, sulfinic acid,
Examples include metal salts of organic compounds of the group comprising phosphoric acids, phosphonic acids, phosphinic acids, alcohols, glycols, phenols, amides, imides, lactams, and sulfonamides, and further examples include metal chelate compounds. Among them,
organic or hydroxycarboxylic acids such as acetic acid, stearic acid, succinic acid, quinnamic acid, benzoic acid,
Metal salts such as t-butylbenzoic acid, nitrobenzoic acid, chlorobenzoic acid, phthalic acid, terephthalic acid, tetrabromophthalic acid, tetrachlorophthalic acid, hydroxyprobionic acid, hydroxybenzoic acid, salicylic acid, and organic acid components, For example, metal salts of polymeric copolymers containing acrylic acid, methacrylic acid, maleic acid, etc. as monomer components are preferably exemplified. In addition, metals of metal salts include lithium,
Sodium, potassium, calcium, magnesium, zinc, aluminum, etc. are preferred, and sodium is particularly preferred. Addition of these metal salt compounds not only further improves the crystallization rate of the modified polyester, but also contributes to improving the thermal oxidative stability. Its usage amount is 0 per total composition.
-20% by weight, preferably 0.1-10% by weight.

The method of adding and blending such metal salt compounds is arbitrary;
For example, it may be applied at any stage during the production of polyester or modified polyester, during melt cross-extrusion, or during injection molding.

The phenolic antioxidant referred to in the present invention is n-octadecyl-3-(4'-hydroxy-3').

5'-di-t-butyl-phenyl)propionate, tetrakis[methylene-3-(3,5-di-t-butyl-
4-hydroxy-phenyl)propionate]methane,
4.4'-Butylidene-bis(3-methyl-6-t-butylphenol), hexamethylene glycol-bis-
[β-(3,5-di-t-butyl-4-hydroxyphenyl)propione, 4,4′-methylene-bis(2
, 6-di-t-butylphenol), 1,3.5-)listyl-2,4,6-)lis(3,5-di-t-butyl-4-hydroxy-benzyl)benzene, 6-(4- hydroxy-3,5-di-t-butylanilino) -2,
4-bis-otatiruthio-1,3,5-triazine,
Tris(3,5-sheet t-7'thyl-4-hydroxyphenyl)isocyanurate, Tris[β-(3,5-di-t-phthyl-4-hydroxyphenyl)propionyl-oxyethyl]isocyanurate), 1. 3.5-4 lis(3',5'-di-t-butyl-4-hydroxybenzyl)in cyanurate, 2,2-thio[diethyl-bis-3-(3,5-di-t-butyl) -4-hydroxyphenyl)propionate], but is of course not limited to these.

The amount of these 7-enol antioxidants added is 0 to 5% by weight, preferably 0.1 to 1% by weight, based on the total composition. ``Any method can be used to blend these into polyester. For example, a method of adding it during or after the production of a polyoxyalkylene compound, a method of adding and blending the modified polyester during polycondensation or production using an extruder, a method of kneading the modified polyester with an extruder, Examples include a method of simply mixing and direct injection molding.

In the present invention, mechanical strength, heat resistance, and dimensional stability can be further improved by incorporating a granular or plate-like inorganic filler. - Examples of the granular or plate-like inorganic fillers used include mica, kaolin, clay, talc, asbeth 1, lucium silicate, lucium sulfate, and lucium carbonate, with mica and talc being particularly preferred. These may be used alone or in combination of two or more. The blending amount is 0 to 200 parts by weight per 100 parts by weight of the modified polyester, and when considering mechanical strength, heat resistance, and fluidity, preferably 10 parts by weight.
~50 parts by weight.

In the present invention, a fibrous reinforcing agent can also be blended in order to further improve heat resistance under high loads, strength at high temperatures, and dimensional accuracy. Examples of the fibrous reinforcing agent used include glass fibers, mineral fibers, carbon fibers, silicon carbide fibers, boron carbide fibers, potassium titanate fibers, and gypsum fibers, with glass fibers and mineral fibers being particularly preferred. A fibrous reinforcing agent whose surface has been treated with a silane coupling agent or the like is preferably used to improve its affinity with the modified polyester. The blending amount of these fibrous reinforcing agents is 0 to 200 parts by weight per 100 parts by weight of the modified polyester, and preferably 5 to 150 parts by weight when considering heat resistance, strength, fluidity, etc.

Furthermore, in the present invention, flame retardancy can be further improved by incorporating a flame retardant.

The flame retardants used are those from Groups ■, ■, and ■ of the periodic table.
Examples include compounds containing elements of groups 1 and 2.

Particularly preferred are halogen compounds, phosphorus compounds, and antimony compounds. These can be used alone or in combination of two or more. Specific examples of flame retardants include (tetrabromo bispheno-7-A or derivatives thereof, tecaglomodiphenyl ether, tetrabromo phthalic anhydride, perchlordicyclofructadiene derivatives, triphenyl phosphate,
Examples include antimony trioxide. )・Rogen-containing polymers can also be exemplified. The blending amount of the flame retardant is 0 to 30 parts by weight per 100 parts by weight of the modified polyester.

Any method may be used to blend the granular or plate-like inorganic filler, fibrous reinforcing agent, and flame retardant. Examples include a method of mixing and extruding together with the modified polyester in an extruder, a method of simply mixing with the modified polyester and directly injection molding, and a method of adding and blending at the time of manufacturing the modified polyester.

The thus obtained composition of the present invention is particularly preferred for injection molding, but it can also be made into molded articles by extrusion molding or other molding methods.

As is clear from the examples described below, the molded product obtained by molding the composition of the present invention has excellent molding processability, can stably obtain a molded product with a good surface appearance, and has low water absorption. It has good thermal oxidative stability.

In addition to other known nucleating agents, thermal oxidation stabilizers, light stabilizers, etc., additives such as plasticizers, lubricants, and colorants may be added to the composition of the present invention. Furthermore, it is also possible to incorporate a small proportion of other types of thermoplastic resins, or to introduce a small proportion of a rubber component in order to improve impact resistance.

The composition of the present invention can be widely used for molding various molded parts, pipes, containers, etc., and can be particularly suitably used for automobile parts, electrical parts, etc. In some cases, fibers, films,
It can also be used for sheets.

The present invention will be explained below with reference to Examples. In addition, in the examples, the intrinsic viscosity of the polymer is 1. V, in phenol/tetrachloroethane (l: 1 part by weight), 25-0,5? /dl
It was determined from the logarithmic viscosity measured in terms of concentration.

The melting point of modified polyester is 7m, the cooling crystallization temperature T<) of the molten state, and the heating crystallization temperature TO from the glass state.
(Measurement of Fl was performed using a Perkin-Elsimer DSC-IB.
Depends on the type. Heat distortion temperature of molded products (ASTM-D64
8. Water absorption rate is ASTM-D570 Vcf! - Measured using the method based on Thermal oxidative stability is 275-60 in air.
It was expressed as the weight loss rate after holding for 30 minutes.

Examples 1-2. Comparative Examples 1 to 3 In a 41 autoclave equipped with a stirrer, dimethyl terephthalate 1942y (10 mol) and ethylene chloride 9! J Coal 1366y (22 mol), varnish f), 1.2y of zinc acetate as an exchange catalyst, and 160~2% under nitrogen atmosphere.
The transesterification reaction was carried out by hot stirring at 10'C for 2 hours ffl. After the theoretical amount of methanol has been distilled off, Table-IK
194 y of 2Na monotrimellitic acid ester of polyoxyalkylene glycol having the composition shown, 2.1 y of IJ phenyl (phosphoric acid) as a heat stabilizer, and 0.7 y of antimony trioxide as a polycondensation catalyst were added. Subsequently, a polycondensation reaction was carried out at 270°C and <1'I'brr. The properties of the obtained polymer are shown in Table-1. 1゜3.5-trimethyl-2,
4,6-)Lis(3,5-di-t-7'chill-4-hiF
Penceen (manufactured by Shell Chemical Co., Ltd., I)
Onox 330) 0.5'% by weight was added and mixed, and then injection molded at a mold temperature of 100°C to obtain a molded product. The injection moldability and physical properties of the obtained molded article are also shown in Table IK. From Table 1, it is clear that the composition of the present invention achieves a low absorption rate while maintaining good crystallization properties, moldability, physical properties, and thermo-oxidative stability.
゛ ・Examples 3 to 6. Comparative Examples 4 to 7 In a 41 autoclave equipped with a stirrer, dimethyl terephthalate 1942y (10 mol) and ethylene glycol:'
zlz1366y (22 mol), polyoxyalkylene glycol 170y1 shown in Table 2, 1.2y of zinc acetate as a transesterification catalyst, and 160-2% under nitrogen atmosphere.
Transesterification was carried out by heating and stirring at 10° C. for 2 hours.

After the theoretical amount of methanol was distilled off, 0.7y of antimony trioxide was added as a heavy bond catalyst.

Triphenyl phosphate g,ly was added as a heat stabilizer. Subsequently, a polycondensation reaction was carried out at 270'C (1'l'orr).The properties of the obtained polymer are shown in Table 2.
0.5% by weight of onox 330, sodium pt-butylbenzoate as an organic acid metal salt-containing compound, ionomer resin (HI-MILAN, manufactured by Mitsui Polychemical Co., Ltd.), glass fiber with a fiber length of 311I as a reinforcing agent ( (manufactured by Shio Fiberglass Co., Ltd.) in the proportions shown in Table 2,
Mixed pellets are made by an extruder, and then the mold temperature is 100%.
A molded article was obtained by injection molding at ℃. The injection moldability and physical properties of the obtained molded article are also shown in Table 2.

As is clear from Table 2, in the composition of the present invention,
Good crystallization characteristics, moldability, and physical properties are maintained, and
A low water absorption rate is achieved.

Example 7. Comparative Examples 8-9 Polyethylene terephthalate ('1.V, = 0.60)
, polyoxyalkylene glycol, calcium stearate as a metal salt compound, tetrakis [methylene-3-(3,5-di-t-phthyl-4
-Hydroxyphenyl) flobionate comethane (manufactured by Cipa-Geigy + Irganoxlolo) -
3, mixed wire pellets were formed using a twin-screw extruder, and the pellets were injection molded at a mold temperature of 100° C. to obtain a molded product. The injection moldability and physical properties of the obtained molded article are shown in Table 3.

As is clear from Table 3, in the composition of the present invention,
Good crystallization properties, moldability, and physical properties are maintained, and low water absorption is achieved.

Claims (1)

[Claims] 1. General formula % formula % (wherein R1 is hydrogen or an n-valent organic group, R2 is C2-
C4 aliphatic hydrocarbon group, and C2/C3+C
4 (molar ratio) is 0.1 or more and less than 1.0, R3 is a hydrocarbon organic group or hydrogen that may contain nitrogen, oxygen, sulfur, phosphorus, or metal elements, and m and n are positive integers. A modified polyester (4) formed by copolymerizing and/or mixing 0.1 to 50% by weight of a polyoxyalkylenated compound represented by A) and at least 0 to 20% by weight based on the total composition. Ionizable metal salts of organic compounds with one acidic proton (average, 0 to 5% by weight of phenolic antioxidants (
A modified polyester composition for molding consisting of Q. 2. The composition according to claim 1, which is obtained by copolymerizing and/or mixing 1 to 15% by weight of a polyoxyalkylene compound with respect to the polyester. 8. The composition according to claim 1, wherein the polyester is polyethylene terephthalate. 4. The composition according to claim 1, wherein the ionizable metal salt of an organic compound having at least one acidic proton is present in an amount of 0.1 to 10% by weight based on the total composition. 5. The phenolic antioxidant is 0.1 per total composition.
12. The composition of claim 11, wherein the amount is 1% by weight.