JPS6160750A - Polyester composition - Google Patents

Abstract

PURPOSE:To obtain a polyester compsn. having excellent heat resistance and improved crystallization velocity, by blending a crystallization promotor and a modified polyolefin wax with a linear polyester. CONSTITUTION:A compsn. consists of 100pts.wt. linear polyester (A) mainly composed of ethylene terephthalate units, 0.05-15pts.wt. crystallization promotor (B) and 0.1-15ps.wt. modified polyolefin max (C) selected from those modified by oxidation, with an unsaturated carboxylic acid or its derivative, with an unsaturated silane compsn. and with a styrene hydrocarbon. Preferred examples of the crystallization promotors are metal salts of a copolymer mainly composed of an arom. olefin and an alpha,beta-unsaturated carboxylic acid.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a polyester composition containing ethylene terephthalate as a main constituent unit, which has excellent heat resistance and an improved crystallization rate.

[Conventional technology]

Conventionally, substantially linear polyesters containing ethylene terephthalate as the main constituent unit, such as polyethylene terephthalate, have excellent properties such as rigidity, heat resistance, and gas barrier properties, and can be used in various shapes such as films, sheets, laminates, and containers. Although it is used as a material for molded objects, it has the disadvantage that it has a slow crystallization rate and cannot be molded at high speed.

Therefore, measures such as increasing the temperature of the molding die have been adopted to improve the crystallization rate of the polyester, but these methods have drawbacks such as thermal deterioration of the resin and warping of the molded product. Therefore, methods have been proposed in which various additives are added to the polyester for the purpose of increasing the crystallization rate of the polyester and improving mechanical properties such as heat resistance and bending rigidity. These methods include methods of blending talc and other various inorganic compounds with the polyester, methods of blending metal salts of aliphatic or aromatic carboxylic acids, methods of blending polyalkylene glycols, alkoxypolyalkylene glycols, ethylene/(meth) ) Methods of blending various polymers such as acrylate copolymers, unsaturated polyesters, and polyamides are also known. Among them, Tokuko Sho 4
No. 5-26225 proposes a copolymer of ethylene or styrene and a salt such as acrylic acid or methacrylic acid, and Japanese Patent Publications No. 55-47058, No. 55-47059 and No. 59-15445 propose filling materials, etc. A technique has been proposed that combines (1) a sodium salt or potassium salt of an affi compound having a pendant carboxyl group and (2) an organic ester; / Sodium salt of maleic anhydride copolymer is exemplified.

Also, JP-A-56-145943, JP-A-56-1276
No. 55 and No. 57-145145 propose a technique of blending a copolymer salt and a polyalkylene glycol or a derivative thereof similar to the above (2).

Also, JP-A No. 56-109244, No. 56-10924
No. 5 proposes a technique of blending polyethylene wax with polyethylene terephthalate resin, and Japanese Patent Publication No. 19998 proposes a technique of blending polyethylene as well.

[Problem that the invention seeks to solve]

However, although the method of blending these additives can considerably improve the crystallization rate of the polyester, sufficient improvement in the crystallization rate to satisfy the current demand for high-speed moldability has not been achieved. The development of even better compounding agents is desired.

The present inventors recognized the above-mentioned demand for a polyester having ethylene terephthalate as its main constituent unit, and as a result of searching for a polyester composition having an excellent crystallization rate and excellent heat resistance, the polyester The present inventors have discovered that when a crystallization accelerator and a specific modified polyolefin wax are added to a polyolefin resin composition, the above-mentioned problems can be solved by achieving effects that exceed those expected from the known techniques described above, and have thus arrived at the present invention.

[Means for solving problems]

To summarize the invention of the present inventor, the present invention consists of a substantially linear polyester having ethylene terephthalate as a main constituent unit (A): 100 parts by weight, a crystallization accelerator (B)
: o, os to 15 parts by weight, and oxidation-modified polyolefin wax, unsaturated carboxylic acid or its derivative graft-modified polyolefin wax, unsaturated epoxy compound-modified polyolefin wax,
Modified polyolefin wax (C) selected from the group consisting of unsaturated silane compound modified polyolefin wax and styrenic hydrocarbon modified polyolefin wax:
0.1 to 15 parts by weight of a polyester composition. The present invention will be explained in detail below.

(About component (A)) The polyester (A) blended into the polyester composition of the present invention is a substantially linear polyester containing ethylene terephthalate as a main constituent unit.

The content of ethylene terephthalate structural units in the polyester is 70 mol% or more, preferably 80 mol% or more. The dicarboxylic acid component units constituting the polyester may include other aromatic dicarboxylic acid component units other than the terephthalic acid component units, which may contain small amounts of other aromatic dicarboxylic acid component units in addition to the terephthalic acid component units. Specific examples of the dicarboxylic acid component unit include isophthalic acid, phthalic acid, and naphthalene dicarboxylic acid. The diol component units constituting the polyester may contain small amounts of other diol component units in addition to the ethylene glycol component units. Specifically, other diol component units other than ethylene glycol component units include propylene glycol, 1.
3-propanediol, 1,4-butanediol, neopentyl glycol, cyclohexanediol, cyclohexane dimetatool, 1,4-bis(β-hydroxyethoxy)benzene, 1,3-bis(β-hydroxyethoxy)benzene, 2.2-bis(4-β-hydroxyethoxyphenyl)propane, bis(4-β-hydroxyethoxyphenyl)sulfone, bis(4-hydroxyphenylmethane, 2.2-bis(4-hydroxyphenyl)propane, etc.) Diol component units having 3 to 20 carbon atoms and polyethylene glycol, polypropylene glycol, having a molecular weight of 300 to 10,000;
Examples include polyalkylene glycol units such as polytetramethylene glycol. In addition to the aromatic dicarboxylic acid component units and the diol component units, the polyester may also contain a small amount of a polyfunctional compound as required. Specific examples of polyfunctional compound component units include trimellitic acid, trimesic acid, pyromellitic acid, aromatic polybasic acids such as 3.3', 5.5'-tetracarboxydiphenyl, butanetetracarboxylic acid, etc. aliphatic polybasic acids, phloroglucin, aromatic polyols such as 1,2,4.5-tetrahydroxybenzene, aliphatic polyols such as gliscent, trimethylolethane, trimethylolprotwin, pentaerythritol, tartaric acid , oxypolycarboxylic acids such as malic acid, and the like.

Further, the polyester may contain a small amount of an oxycarboxylic acid compound such as p-hydroxybenzoic acid in addition to the aromatic dicarboxylic acid component unit, the diol component unit, and the polyfunctional compound.

The composition of the constituent components of the polyalkylene terephthalate is:
The content of terephthalic acid component units is usually 40 to 51
The content of aromatic dicarboxylic acid component units other than terephthalic acid component units is usually 0 to 10 mol%, preferably O to 7 mol%. range, the content of ethylene glycol component units is usually 35 to 51 mol%,
It is preferably in the range of 40 to 50.5 mol%, and the content of diol component units other than ethylene glycol component units is usually in the range of O to 15 mol%, preferably 0 to 10 mol%, and the polyfunctional compound component. The content of units is usually in the range of 0 to 10 mol%, preferably in the range of O to 8 mol%. In addition, the intrinsic viscosity of the polyester [
η] (value measured at 50°C in p-chlorophenol solution) is usually 0.45 to 2. Oaj/g, preferably in the range of 0.50 to 1.8 J/g, the melting point usually in the range of 180 to 280°C, preferably 200 to 270°C, and the glass transition temperature usually in the range of 40 to 140°C. , preferably in the range of 50 to 120°C.

[About component (B)] As the crystallization promoter (B) to be blended into the polyester composition of the present invention, any known ones can be used. For example, solid inorganic compounds such as talc and clay, caproic acid, etc. Salts of organic carboxylic acids, such as stearic acid, montanic acid, benzoic acid, terephthalic acid, 5-(N-phthalimido)-caproic acid, such as sodium, potassium salts:!
! Mention may be made of organic polymers having pendant carboxyl groups, such as metal salts of copolymers of olefins or aromatic olefins with unsaturated carboxylic acid compounds such as acrylic acid or methacrylic acid or maleic anhydride. Of course, these may be used in combination, and among these crystallization promoters, aromatic olefins and α, β
Particularly preferred are metal salts of copolymers containing unsaturated carboxylic acids as a main component.

[About component (C)]

Component (C) blended into the polyester composition of the present invention is various modified polyolefin waxes.

Of course, these may be used in combination.

Specifically, the polyolefin waxes used as raw materials for the modified polyolefin waxes include polyolefin waxes obtained by thermal decomposition, radical decomposition, etc. of polyolefins such as polyethylene, polypropylene, and poly4-methyl-1-pentene, and high-pressure Polyethylene wax produced by radical polymerization of ethylene, as well as ethylene, propylene,
Or these olefins and propylene, l-hexene,
Examples include polyolefin waxes obtained by medium/low pressure polymerization of α-olefins such as 4-methyl-1-pentene, 1-octene, and -decene in the presence of a transition metal compound. Among these polyolefin waxes, those containing ethylene as a main component are preferred.

The intrinsic viscosity [η] (value measured at 135°C in decalin solvent) of the polyolefin wax is usually 0.0.
4 to 1.0+1!7/g, preferably 0.06
Or 0.8d! /g range.

As the oxidized polyolefin wax, the above-mentioned polyolefin wax can be prepared by a known method, for example, Japanese Patent Publication No. 48-37.
991, JP-A No. 48-29876, and the like can be used.

The oxygen content of oxidized polyolefin wax is usually 0.1
to 1)% by weight, preferably 0.2 to 8% by weight, and the contained oxygen exists in the form of a hydroxyl group, an aldehyde, a carbonyl group such as a ketone, or a carboxyl group. Oxidized polyolefin wax is also used as a raw material wax when producing other modified polyolefin waxes described below. Modified waxes used in the compositions of the present invention described below include those obtained in this manner. It is also possible to use modified waxes containing ester groups derived from oxidized polyolefin waxes and alcohols and/or organic acids.

Unsaturated carboxylic acids or derivatives thereof The unsaturated carboxylic acids (seven acids) used in the production of graft-modified polyolefin wax include (meth)acrylic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid,
Citraconic acid, crotonic acid, isocrotonic acid, nadic acid (endocys-bicyclo(2,2,1)hept-5
-ene-2゜3-dicarboxylic acid), or derivatives thereof, such as acid halides, amides, imides, anhydrides, esters, etc. Specifically, maleyl chloride, maleimide, maleic anhydride, etc. , citraconic anhydride, monomethyl maleate, acrylic acid amide, dimethyl maleate, glycidyl maleate, methyl (meth)acrylate, ethyl (meth)acrylate, n-
Examples include butyl (meth)acrylate and 2-ethylhexyl (meth)acrylate. Among these,
Anhydrides and esters are preferred, particularly maleic anhydride, nadic anhydride, ethyl (meth)acrylate, n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate.

The graft-modified polyolefin wax can be prepared by a known method,
For example, under the melting conditions of the polyolefin wax, the above monomers are combined with a radical initiator, such as an organic peroxide,
It can be produced by reaction using an organic bereester azo compound.

The amount of graft modification is usually 0.2 to 5 oiiit when expressed by the monomer content in the graft modified polyolefin.
%, preferably 0.5 to 40% by weight.

The unsaturated carboxylic acid or its derivative or graft-modified polyolefin wax is also used as a raw material wax for producing other modified polyolefin waxes described below. Furthermore, a modified polyolefin wax containing an ester group derived from an unsaturated carboxylic acid or its derivative graft-modified polyolefin wax and an alcohol can also be used.

As the unsaturated epoxy compound-modified polyolefin wax, known waxes, such as those obtained by the method described in JP-A-55-157613, can be used as they are. Examples of unsaturated epoxy compounds include allyl glycidyl ether, 2-methylallyl glycidyl ether, glycidyl ether of 〇- or m- or p-allyl phenol, 2-(o- or m- or p-allylphenyl) ethylene oxide, isopropenyl Allyl-type unsaturated epoxy compounds such as glycidyl ether of phenol, styrene-type unsaturated epoxy compounds, and even 3,4-epoxy-
Epoxy group-containing aliphatic unsaturated compounds such as 1-butene and 3.4-epoxy-3-methyl-1-butene can be mentioned, and 10-4 to 3xlO-2g of epoxy group per 1g of polyolefin wax can be mentioned. It is preferable to use a modified polyolefin wax containing within the range.

As the unsaturated silane compound-modified polyolefin wax, for example, those described in JP-A-54-145785 can be used. That is, it is graft-modified with, for example, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(methoxyethoxy)silane, etc., and the amount of grafting is usually 3 to 45% by weight.
, and (5 to 30% by weight) is preferred.

The styrenic hydrocarbon-modified polyolefin wax is prepared using styrene, α-methylstyrene, p-methylstyrene, 〇-methylstyrene, 2.4
-Dimethylstyrene, 2,5-dimethylstyrene, etc. can be used. Specifically, for example, one manufactured by the method disclosed in JP-A No. 58-65713 can be used. The content of styrenic hydrocarbons in the modified wax is usually in the range of 1 to 90% by weight, preferably 5 to 75% by weight.

As described above, oxidized polyolefin waxes and modified waxes obtained by graft-modifying unsaturated carboxylic acid or its derivative graft-modified polyolefin waxes with styrene hydrocarbons are also included in the styrenic hydrocarbon-modified polyolefin waxes used in the present invention.

Among the above-mentioned modified polyolefin waxes, oxidized waxes, waxes further grafted with oxidized styrene yarn threads, and waxes grafted with α,β-unsaturated carboxylic acid esters are particularly preferred.

[Blending ratio of each component]

The blending ratio of component (B) to the polyester (A) is in the range of 0.05 to 15 parts by weight, more preferably 0.1 to 10 parts by weight per 100 mff of (A). Similarly, the blending ratio of (C) is 0.1 to 15 parts by weight, more preferably 0.1 to 15 parts by weight per 100 parts by weight of (A).
．． It ranges from 2 to 10 parts by weight.

〔Effect of the invention〕

Only when the blending ratio of (B) and (C) to the polyester (A) is within the above-mentioned essential range, sufficient crystallization rate and sufficient heat resistance improvement effects specific to the composition of the present invention can be achieved. appears. If the blending ratio of (B) is less than 0.05 parts by weight, a sufficient crystallization rate cannot be obtained, and if it is more than 15 parts by weight, mechanical properties such as bending strength will deteriorate. Similarly, if the blending ratio of component (C) is less than 0.1 part by weight, sufficient crystallization promoting effect will not be exhibited, and if it is more than 15 parts by weight, mechanical properties such as flexural strength will deteriorate. It becomes like this.

[Other ingredients]

The polyester composition of the present invention comprises the polyester (A
), may consist of only the three essential components such as (B) and (C) above, but various compounding agents or additives conventionally blended with polyester may be blended within the range that does not impair its practicality. can do. For example, reinforcing fillers such as diatomaceous earth, calcium carbonate, silica, silica alumina, alumina, carbon mica, titanium oxide, carbon fiber, glass fiber, aramid fiber, ester (including polyester), ether (including polyether), etc. Various plasticizers, lubricants, surfactants, thickeners such as pentaerythritol, trimellitic acid, pyromellitic acid, flame retardants,
Examples include ultraviolet stabilizers, antioxidants, mold release agents, and colorants. The blending ratio of these compounding agents or additives is appropriate.

Furthermore, various other polymers, such as polyolefins, olefin copolymers, or modified polymers thereof,
Polystyrene, polyamide, polycarbonate, polyacetal, polysulfone, polyphenylene oxide, fluororesin, silicone resin, epoxy resin, etc. may be blended.

The polyester composition of the present invention can be prepared by mixing a polymer mixture consisting of each essential component and, if necessary, compounding agents and additives, and melt-kneading the mixture according to a conventionally known method, or by mixing these essential components and necessary additives. Depending on the situation, it can also be obtained by adding various compounding agents and additives to polyester metal.

〔Example〕

Next, the present invention will be specifically explained using examples.

In addition, in the examples, molding and evaluation of the polyester compositions were performed by the following method.

Press molding The dried polyester composition was molded using a press molding machine (molding temperature: 290°C) into 15 cm x 10 cm + xO,
A rapidly cooled press sheet having a shape of 2 cm was produced.

Injection molded Toshiba! B. Using an injection molding machine model 15-35P manufactured by Machine aS, a bending test sample with a thickness of 0.2 c++ was prepared at a mold temperature of 70°C.

Width 1.27 cm, length 6.3 cut from a bending test press sheet
A 5 cm strip test piece or an injection molded test piece of the same shape was tested using an Instron tensile tester model 1) 22 at 23° C. and a crosshead speed of 5 mm/min.

Width 1.2 cut from heat-resistant press sheet or injection molded sample
Using a rectangular test piece of 7 cm and length 2 cm+, a DuPont Dynamic Mechanical Analyzer Model 9 was used.
The temperature dependence of the elastic modulus was measured using Model 81. 100℃
The ratio of the elastic modulus at 30℃ to that at 30℃ E100 /30
was used as an index representing heat resistance.

ΔHH/ΔHc It was measured using a differential calorimeter (abbreviated as DSC, type ■ manufactured by Perkin Enmer Co., Ltd.).

That is, approximately 5a+g of sample was weighed from a quenched press sheet or an injection sheet, and heated at 20°C/win.
After increasing the temperature at 290℃ and holding it for 5ml at 20℃/win
DSC measurements were performed under the condition that the temperature was raised at . From the obtained calorific curve, the calorific value ΔH+ was determined from the peak area at the crystallization temperature when the temperature was raised, and the calorific value ΔHc was determined from the peak area at the crystallization temperature when the temperature was lowered.

ΔHH/ΔHc obtained in this way is an index of ease of crystallization, and the smaller this value is, the easier it is to crystallize the polyester.

Examples 1-9, Comparative Examples 1-7 Intrinsic viscosity 0.65L! ! /g of polyethylene terephthalate, various crystallization accelerators, and modified polyolefin wax were triblended in the proportions shown in Table 1, and then 20 m
mφ extruder (Dulmage type screw, full flight screw if glass fiber is mixed, L/D-2
8) for melt mixing.

Table 1 shows the results of examining the physical properties of the polyester composition thus obtained. The compositions of the invention correspond to (
It can be seen that the composition has better properties than the composition containing only components A) and (B).

In Table 1, each symbol is as follows.

fllB-1 is sodium stearate.

(2) B-2 is sodium 5-(N-phthalimido)-caproate.

(31B-3 is a sodium salt of ethylene/methacrylic acid copolymer (Surlyn 1605, manufactured by DuPont).

(41B-4 is a sodium salt of styrene/methacrylic acid copolymer (methacrylic acid content: 10 mo 1%, degree of neutralization near 5%), and was synthesized as in Reference Example 1 below.

Reference example 1> 624 g of styrene in a reactor equipped with a stirrer.

After charging 33.8 g of methacrylic acid and 920 ml of toluene and bubbling with nitrogen for 15 minutes, the reactor was sealed with nitrogen and the temperature was raised to 100°C.

A dropping funnel was charged with 2 g of benzoyl peroxide and 60 ml of toluene, and after bubbling with nitrogen for 15 minutes, the mixture was added dropwise to the reactor over about 30 minutes. After the dropwise addition was completed, the reaction was continued for 4 hours, and the reaction product was precipitated into a large excess of hexane.

The yield of molded polymer was 292 g. GPC(TH
F solvent, the number average molecular weight in measured at 40 ° C. is 84,
000, and the molecular weight distribution Mw/Mn was 1.5. The methacrylic acid content in the molded polymer determined by elemental analysis was 10 mo1%.

In a reactor equipped with a cooler, 200 g of the styrene/methacrylic acid copolymer synthesized by the above method and 120 g of toluene were added.
0ml was charged and the temperature was raised to 100°C. Using a dropping funnel, an aqueous solution containing 6.18 g of NaOH was added dropwise over 5 minutes, and the reaction mixture was reacted for 4 hours. The resulting reaction solution was precipitated in hexane to recover the precipitated polymer. The degree of neutralization of the molded polymer is 7
It was 5%.

+51B-5 is a sodium salt of a styrene/methacrylic acid copolymer (methacrylic acid content: 7, 15 mo1%, medium strength: 5%), and was synthesized in the same manner as B-4.

(61C-1) is a sample obtained by graft copolymerizing 14-t% of n-butyl methacrylate to [η)-0,234/g polyethylene wax, and was synthesized by the following method (Reference Example 2). Various modified waxes were also synthesized using the same method.

Reference example 2> The plate [η] of the boot olefin is 0.23d! /g of polyethylene wax 59
5 g was charged into the glass reactor of 1) and dissolved at 140°C. Then, n-butyl methacrylate 105
g and g-tart, -butyl peroxide 9.0 g
were added and reacted by heating for 4 hours. Then, 140℃
The mixture was aerated for 1 hour under a vacuum of 10 mm+Hg to remove volatile components, and then cooled and solidified. Obtained n
- Butyl methacrylate grafted amount of n-butyl methacrylate in polyethylene wax is 14wt
%Met.

(7) C-2 is n-butyl methacrylate 40-t
% graft copolymerized modified polyethylene wax. ((V) is 0.07d!/g, propylene is 2m
O1% copolymerized wax was used as a raw material before modification. ) +81G-3 is a polyethylene wax obtained by graft copolymerizing 30-t% of ethyl methacrylate.

([η] is 0.134/g, propylene content is 41) 1
o1% polyethylene wax was used as a raw material. ) +91C-4 is 2-ethylhexyl methacrylate 5
It is a 0wt% graft copolymerized polyethylene wax. (The raw material is the same as the raw material wax for C-2.) αQl C-5 is a polyethylene wax obtained by graft copolymerizing 10 wL% of 2-ethylhexyl methacrylate. (The raw material is the raw material wax of C-1.) (1 Li C-6 is an oxidized wax with an oxygen content of 4.9% by weight. ([η] is 0.23 d!/g, and the propylene content is 4 mo1% polyethylene wax was used as a raw material.) θ2) C-7 is an oxidized wax with an oxygen content of 7.0% by weight. (The raw material is the same as the raw wax of C-1,)01)
C-8 is an oxidized wax with an oxygen content of 0.9% by weight (the raw material is the same as the raw wax for C-2) and 35% styrene.
It is a modified wax that has been graft copolymerized in wt%.

04) C-9 is a wax co-grafted with 20 wt% styrene and 10 wt% acrylonitrile. (The raw material is C.
It is the same as the raw material wax of -3. ) θ5) C-1
0 is a maleic anhydride grafted wax with a value of 30 mg/g. (The raw material is the same as the raw material wax for C-3.) (16) C-1) uses 7wt of vinylmethoxysilane.
% grafted wax. (The raw material is the same as the raw wax for C-1.)

Claims (1)

[Claims] (1) Substantially linear polyester having ethylene terephthalate as the main constituent unit (A): 100 parts by weight, crystallization accelerator (B): 0.05 to 15 parts by weight, oxidation-modified polyolefin wax, unsaturated carboxylic acid Modified polyolefin wax (C) selected from the group consisting of a graft-modified polyolefin wax or a derivative thereof, a polyolefin wax modified with an unsaturated epoxy compound, a polyolefin wax modified with an unsaturated silane compound, and a polyolefin wax modified with a styrene hydrocarbon: 0.1 to 15% by weight A polyester composition comprising: