JPH0689235B2 - Method for producing glass fiber reinforced polyester resin composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a glass fiber reinforced polyester resin composition. More specifically, a glass that has good mechanical properties, particularly impact resistance at low temperatures, and that does not impair the rigidity that is a characteristic of glass fiber reinforced resin, and that has excellent moldability and mold releasability. The present invention relates to a method for producing a fiber-reinforced polyester resin composition.

<Prior Art> Aromatic polyesters represented by polyethylene terephthalate and polybutylene terephthalate are used in a wide range of fields such as electric and electronic device parts and automobile parts due to their excellent properties.

In particular, for applications requiring rigidity, a method of blending an aromatic polyester with an inorganic filler such as glass fiber is generally performed, and at this time, notched impact strength is also partially improved.

However, in applications where particularly high notch impact strength is required, the incorporation of a reinforcing agent such as glass fiber alone is not sufficient, and therefore many improvement methods have been conventionally proposed.

Among them, a copolymer of ethylene and α-olefin having 3 or more carbon atoms, or a copolymer of α-olefin having 3 or more carbon atoms and a non-conjugated diene, as disclosed in JP-A-60-40154. On the other hand, the method of blending a modified ethylene copolymer obtained by graft-polymerizing an unsaturated epoxy monomer is relatively excellent.

On the other hand, for the purpose of improving tensile strength, flexural strength, hydrolysis resistance, etc., thermoplastic polyester resin, glass fiber surface-treated with a polyfunctional epoxy compound, and neutral or partially neutralized Montanwa A resin composition comprising a tuss salt or a montan wax ester salt
It is disclosed in Japanese Patent Publication No. 55-52340.

<Problems to be Solved by the Invention> However, when glass fibers are simply added to the method for improving the impact resistance of the aromatic polyester described in JP-A-60-40154, the resistance to Although the impact resistance is certainly improved, only the ones that are not suitable for practical use are obtained, such as the rigidity characteristic of glass fiber reinforced resin is impaired, or the molding fluidity and releasability are extremely poor. I can't.

Further, in the resin composition described in JP-A-55-52340, the glass fiber surface-treated with a polyfunctional epoxy compound is used for reinforcing the aromatic polyester, and is reinforced by tensile strength and bending strength. Although the effect was large, it was unsatisfactory in terms of impact strength.

Therefore, the present invention provides a method for producing a resin composition which has good impact resistance at low temperature, minimizes loss of rigidity, and has excellent balance of molding fluidity and releasability. It is an issue.

<Means for Solving Problems> As a result of intensive studies to solve the above problems, the present inventors have found that when glass fiber and a specific modified olefin copolymer are added to an aromatic polyester, The inventors have found that the above-mentioned problems can be solved by using glass fibers after surface-treating them with a polyfunctional epoxy compound, and arrived at the present invention.

That is, the present invention relates to (A) 100 parts by weight of aromatic polyester, (B) 3 to 200 parts by weight of glass fiber surface-treated with 0.01 to 10% by weight of a polyfunctional epoxy compound based on glass fiber, And (C) the melt flow rate is 0.0
0.01 to 20% by weight based on the copolymer of ethylene and α-olefin having 3 or more carbon atoms in the range of 5 to 100 or the copolymer of ethylene, α-olefin having 3 or more carbon atoms and non-conjugated diene Modified olefin copolymers 1-100 obtained by graft-reacting unsaturated epoxy monomers
A method for producing a glass fiber reinforced polyester resin composition, which comprises blending parts by weight.

The (A) aromatic polyester used in the production method of the present invention is a polyester having an aromatic ring in a polymer chain unit, and is an aromatic dicarboxylic acid (or an ester-forming derivative thereof) and a diol (or an ester-forming derivative thereof). A polymer or a copolymer obtained by a condensation reaction containing a functional derivative) as a main component.

Examples of the aromatic dicarboxylic acid used herein include terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, bis (p-carboxyphenyl) methane, anthracene dicarboxylic acid, 4 Examples include 4,4'-diphenyldicarboxylic acid, 4,4'-diphenyletherdicarboxylic acid, 1,2-bis (phenoxy) ethane-4,4'-dicarboxylic acid and ester-forming derivatives thereof.

If the acid component is 40 mol% or less, adipic acid,
Aliphatic dicarboxylic acids such as sebacic acid, azelaic acid and dodecanedioic acid, alicyclic dicarboxylic acids such as 1,3-cyclohexanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid and aromatic dicarboxylic acids such as ester-forming derivatives thereof You may substitute by the dicarboxylic acid other than.

As the diol component, an aliphatic diol having 2 to 10 carbon atoms, that is, ethylene glycol, propylene glycol, 1,4-butanediol, neopentyl glycol,
1,5-pentanediol, 1,6-hexanediol, decamethylene glycol, cyclohexanediol, cyclohexanedimethanol, etc.
400 to 6,000 long chain glycols, that is, polyethylene glycol, poly-1,3-propylene glycol, polytetramethylene glycol and the like and mixtures thereof may be copolymerized.

Examples of preferred aromatic polyesters used in the production method of the present invention include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate, polycyclohexylene dimethylene terephthalate, polyethylene-2,6-naphthalate, polyethylene-1, 2-bis (phenoxy)
Examples thereof include ethane-4,4'-dicarboxylate, and of these, polybutylene terephthalate having the appropriate mechanical strength is most preferable.

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. When the relative viscosity of the aromatic polyester is less than 1.2, sufficient mechanical strength cannot be obtained, and when it is 1.8 or more, a molded article having a good surface gloss cannot be obtained, which is not preferable.

The glass fiber (B) used in the production method of the present invention is generally used for resin reinforcement, and is surface-treated with a polyfunctional epoxy compound before use. The fiber length of the glass fiber is not particularly limited, but a chipped strand having a length of 1 to 5 mm can be preferably used.

The polyfunctional epoxy compound used for the surface treatment of glass fiber is a compound containing at least two epoxy groups in one molecule and containing no halogen. As a preferred example of the polyfunctional epoxy compound, for example, bisphenol type epoxy compound obtained by reacting bisphenol and epichlorohydrin at various ratios, novolak type epoxy compound obtained from novolak resin and epichlorohydrin, polycarboxylic acid and epichlorohydrin Glycidyl obtained from obtained polyglycidyl esters, alicyclic compound-type epoxy compounds obtained from alicyclic compounds (eg, dicyclopentadiene), aliphatic compounds having alcoholic hydroxyl groups (eg, butanediol, glycerin, etc.) and epichlorohydrin Epoxy group-containing copolymers composed of unsaturated monomers having an epoxy group such as ethers, epoxidized polybutadiene and glycidyl methacrylate, and other unsaturated monomers such as ethylene And the like. Among these polyfunctional epoxy compounds, more preferred are those represented by the following general formulas (I) and (II) (In the formula, R is an alkyl group having 4 to 40 carbon atoms, a cyclohexane ring, a cyclohexene ring or a benzene ring, and n is an integer of 0 to 30.) and bisphenol A
Type epoxy compound, ethylene / glycidyl methacrylate copolymer, ethylene / vinyl acetate / glycidyl methacrylate copolymer, ethylene / carbon monoxide / glycidyl methacrylate copolymer, ethylene / glycidyl acrylate copolymer, etc. Of these, the bisphenol A type epoxy compound represented by the formula (II) is the most preferable. The polyfunctional epoxy compounds listed above may be used in combination of two or more.

The amount of multifunctional epoxy compound used is based on glass fiber
It is necessary to treat it so as to contain 0.01 to 10% by weight, preferably 0.1 to 5% by weight. If the amount of the polyfunctional epoxy compound attached is less than 0.01% by weight, the impact resistance and rigidity are insufficiently improved, whereas if it exceeds 10% by weight, mechanical properties tend to deteriorate, which is not preferable.

The method of surface-treating the glass fiber with a polyfunctional epoxy compound is not particularly limited, but preferably aminosilane, epoxysilane, when sizing the glass fiber,
A preferable method is to use a polyfunctional epoxy compound as a part or all of the glass fiber sizing agent together with a silane coupling agent such as vinylsilane or alkoxysilane, or a coupling agent such as a titanate coupling agent. Further, a method of using an acid anhydride or an amine-based curing agent together with the epoxy compound is also preferable.

As the coupling agent, γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, N-β
Aminosilane such as-(N-vinylbenzylaminoethyl) -γ-aminopropyltrimethoxysilane and γ
-Epoxysilanes such as glycidoxypropyltrimethoxysilane are particularly preferably used.

The amount of glass fiber added in the production method of the present invention is 3 to 200 parts by weight with respect to 100 parts by weight of the aromatic polyester.
It is preferably 5 to 100 parts by weight.

In the method of the present invention, in order to improve the impact resistance of the aromatic polyester, (C) the melt flow rate is 0.05.
To 100 copolymers of ethylene and α-olefins having 3 or more carbon atoms or ethylene, α-olefins having 3 or more carbon atoms and non-conjugated dienes (hereinafter both are collectively referred to as unmodified The modified olefin copolymer obtained by graft-reacting 0.01 to 20% by weight of an unsaturated epoxy monomer with respect to the olefin copolymer) is used.

Α with 3 or more carbon atoms in unmodified olefin copolymer
-Olefin is propylene, butene-1, pentene-
1,3-methylpentene-1, octacene-1, etc., and propylene and butene-1 can be preferably used. Further, the non-conjugated diene is 5-methylidene-2-norbornene, 5-ethylidene-2-norbornene, 5-vinyl-2-norbornene, 5-propenyl-2-norbornene, 5-isopropenyl-2-norbornene, 5-
Crotyl-2-norbornene, 5- (2-methyl-2-
Butenyl) -2-norbornene, 5- (2-ethyl-2)
-Butenyl) -2-norbornene, 5-methacrylnorbornene, norbornene compounds such as 5-methyl-5-vinylnorbornene, dicyclopentadiene, methyltetrahydroindene, 4,7,8,9-tetrahydroindene, 1,5-cyclo Octadiene, 1,4-hexadiene, isoprene, 6-methyl-1,5-heptadiene, 11-ethyl-1,11-tridecadiene and the like, preferably 5-
Methylidene-2-norbornene, 5-ethylidene-2-
Norbornene, dicyclopentadiene, 1,4-hexadiene and the like can be used.

In the unmodified olefin copolymer consisting of ethylene and α-olefin having 3 or more carbon atoms, the copolymer ratio of ethylene and α-olefin having 3 or more carbon atoms is preferably 40/60 to 99/1 (molar ratio), It is particularly preferably 70/30 to 95/5 (molar ratio).

The copolymerization amount of the α-olefin having 3 or more carbon atoms in the unmodified olefin copolymer consisting of ethylene, α-olefin having 3 or more carbon atoms and the non-conjugated diene is 1 to 60 mol%.
Is more preferable, 5 to 40 mol% is particularly preferable, and the copolymerization amount of the non-conjugated diene is preferably 0.1 to 20 mol%, particularly preferably 0.5 to 10 mol%.

Further, the melt flow rate of the unmodified olefin copolymer is required to be in the range of 0.05 to 100, preferably 0.5 to 30, and when it is out of this range, the impact resistance of the aromatic polyester is required. The improvement effect of is small. Here, the melt flow rate is ASTM D-1238-65T (measurement temperature 190
℃) and the unit is g / 10 minutes.

Specific examples of the unmodified olefin copolymer include ethylene / propylene copolymer, ethylene / butene-1 copolymer, ethylene / propylene / dicyclopentadiene copolymer, ethylene / propylene / 5-ethylidene-2-norbornene. Preferred examples thereof include copolymers, and among them, ethylene / propylene copolymers and ethylene / butene-1 copolymers containing no non-conjugated diene have good heat resistance and can be more preferably used.

The unsaturated epoxy monomer obtained by grafting the unmodified olefin copolymer to obtain a modified olefin copolymer is an unsaturated glycidyl ester represented by the following general formula (III), or a general formula ( Examples thereof include glycidyl ethers represented by IV), epoxy alkenes represented by general formula (V), and p-glycidyl styrenes.

(However, in the formula, R ^{1 to} R ³ are each a hydrocarbon group having at least one ethylenically unsaturated bond, and R ⁴ is hydrogen or an alkyl group having 1 to 6 carbon atoms.) Specifically, Glycidyl acrylate, glycidyl methacrylate, glycidyl ethacrylic acid, monoglycidyl ester of itaconic acid, diglycidyl ester of butenedicarboxylic acid, monoglycidyl ester of butenedicarboxylic acid, diglycidyl ester of tetrahydrophthalic acid, 2-methylallylglycidyl ether, vinyl-glycidyl ether , 3,4-epoxybutene, 3,4-epoxy-3-methyl-1-butene, vinylcyclohexene monoxide, p
-Glycidyl styrene and the like can be mentioned, and glycidyl methacrylate can be preferably used. Two or more kinds of these unsaturated epoxy monomers may be used in combination.

The graft reaction amount of the unsaturated epoxy monomer is preferably 0.01 to 20% by weight, more preferably 0.05 to 5% by weight. If the graft reaction amount of the unsaturated epoxy monomer is less than 0.01% by weight, the impact resistance is not sufficiently improved, and if it exceeds 20% by weight, the heat resistance of the aromatic polyester is impaired. Is also not preferable. The term "graft reaction" as used herein means that the unsaturated epoxy monomer is chemically bonded to the unmodified olefin copolymer.

The modified olefin copolymer is produced by a conventional method, for example, an unmodified olefin copolymer having a melt flow rate of 0.01 to 100 is mixed with an unsaturated epoxy compound and an organic peroxide as an initiator. 0.01 to combined
It can be easily produced by adding 5% by weight and melt-kneading at 150 to 250 ° C. However, the graft reaction of the unmodified olefin copolymer having a non-conjugated diene as a copolymer component does not use an organic peroxide, and the thermal addition to the residual carbon-carbon double bond ( 200 to 3 by adding unsaturated epoxy compound using ene reaction)
It is preferable to melt and knead at 00 ° C for production. As a device for melt mixing, a screw extruder, a Banbury mixer, or the like can be used.

When an organic peroxide is used as an initiator in the production of the modified olefin copolymer, it preferably has a molecular weight of 140 or more. Specifically, tert-butyl cumyl peroxide,
Di-tert-butyl peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane, 2,5-dimethyl-2,5-di (tert-butylperoxy) ) Hexin-3, α, α′-di (tert-butylperoxy) diisopropylbenzene and the like.

The amount of the modified olefin copolymer added is 1 to 100 parts by weight, preferably 2 to 50 parts by weight, based on 100 parts by weight of the aromatic polyester. When the amount added is less than 1 part by weight, the effect of improving impact resistance is small, and when the amount added exceeds 100 parts by weight, the mechanical properties of the aromatic polyester tend to be deteriorated.

Incidentally, with respect to the resin composition obtained by the production method of the present invention,
When a compound that accelerates the reaction between the epoxy compound and the carboxylic acid is further added, the impact resistance of the aromatic polyester can be further improved. Examples of these compounds include tertiary amines such as triphenylamine and 2,4,6-tris (dimethylaminomethyl) phenol, phosphite esters such as triphenylphosphite and triisodecylphosphite, and triphenylallylphosphonium. Phosphonium compounds such as bromide, tertiary phosphines such as triphenylphosphine, carboxylic acid metal salts such as lithium stearate and calcium stearate, sodium dodecylbenzene sulfonate, 3,5
-Sulfonic acid metal salts such as sodium dicarbomethoxybenzenesulfonate, sulfate ester salts such as sodium lauryl sulfate, and the like.
0.001 to 5 parts by weight is preferably added to 0 parts by weight.

Also, small amounts of other thermoplastics (eg, polyamide,
Polyacetal, styrene resin, polycarbonate,
Polysulfone, polyphenylene oxide, etc.) can also be added.

The method for producing the composition of the present invention is not particularly limited, for example, aromatic polyester, glass fiber surface-treated with a polyfunctional epoxy compound, modified olefin copolymer and optionally other additives after dry blending, and then melted. The method of mixing is mentioned.

The polyester resin composition produced by the present invention can be easily molded by a usual method such as injection molding or extrusion molding, and the molded product obtained exhibits excellent performance.

<Example> Hereinafter, the effect of the present invention will be described in more detail with reference to examples.
In the following examples, the melt flow rate was changed to MFR.
Abbreviated.

Reference Example 1 (Production of Modified Olefin Copolymer A) 2 parts by weight of glycidyl methacrylate and organic peroxide based on 100 parts by weight of ethylene / propylene copolymer of MFR1.9 (copolymerization amount of propylene: 26 mol%). 0.65 parts by weight of 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane (initiator), which is a substance, is charged into a Henschel mixer in which nitrogen is passed, and the mixture is stirred for 5 minutes to form a uniform mixture. I made it. This mixture is extruded with L / D28 using a 40 mmφ extruder equipped with a tip dullage type screw, at a screw rotation speed of 60 rpm and a cylinder temperature of 200 ° C.,
A modified olefin copolymer (A) was obtained.

After crushing this pellet, unreacted glycidyl methacrylate was extracted with acetone for 20 hours using a Soxhlet extractor. After drying the pellet, the infrared absorption spectrum was measured to quantify the graft reaction amount of glycidyl methacrylate. As a result, glycidyl methacrylate
It was found that the graft reaction was 1.4% by weight.

Reference Example 2 (Production of Modified Olefin-Based Copolymers B to D) In the same manner as in Reference Example 1, various unmodified olefin-based copolymers shown in Table 1 were grafted with glycidyl methacrylate to be modified. Olefin-based copolymer (BD)
Got However, for those containing non-conjugated diene in the copolymerization component (C, D), the organic peroxide as an initiator was not used at the time of modification.

The results are shown in Table 1.

Reference Example 3 (Production of Modified Olefin Copolymers E and F) Maleic anhydride and maleimide were added as graft reaction components to the unmodified olefin copolymer used in Reference Example 1 for comparison. Modified olefin copolymers (E, F) were obtained in the same manner as in Reference Example 1 except that the amount of the organic peroxide shown in Table 1 was used.

The results are shown in Table 1.

Examples 1 to 4 and Comparative Examples 1 to 6 100 parts by weight of polybutylene terephthalate having a relative viscosity of 1.48, after treating the surface with aminosilane, bisphenol A type epoxy resin (1% by weight per glass fiber)
Fiberglass (3mm long tip strand) bundled in 20
Parts by weight and 10 parts by weight of the modified olefin copolymer A produced in Reference Example 1 were dry blended, and melt-mixed and pelletized by an extruder with an internal diameter of 40 mm and a single screw screen set at 250 ° C. The resulting pellets were then molded using a 5-ounce screw-in-line type injection molding machine set at 250 ° C to evaluate releasability and ASTM No. 1 dumbbell, 1/2 "width Izod impact. Create a test piece and a bending test piece and perform an Izod impact test at 23 ° C and -30 ° C.
A tensile test and a bending test at 23 ° C. were performed. In addition, MFR was measured using a part of the pellet. The results are shown in Table 2.
Shown in.

In addition, the modified olefin copolymers (BD) produced in Reference Example 2 were added (Examples 2 to 4), and the modified olefin copolymer was not added for comparison (Comparative Example 1). Examples in which the modified olefin copolymers (E, F) produced in Reference Example 3 were melt mixed (Comparative Examples 2 and 3), ethylene / glycidyl methacrylate copolymer (90/10 weight ratio, MFR = 3) 10 An example in which parts by weight were melt-kneaded (Comparative Example 4), an example in which an unmodified olefin copolymer was added (Comparative Example 5), and a vinyl acetate resin or an acrylic resin instead of the epoxy compound was used as the surface treatment agent for the glass fiber. The results are also shown in Table 2 for the used examples (Comparative Examples 6 and 7).

From the results of Table 2, the resin composition obtained by the production method of the present invention shows that the tensile strength, the elongation at break, the rigidity represented by the bending elastic modulus and the bending stress, and the impact resistance represented by the notched Izod impact value. Further, it can be seen that impact resistance at low temperature, molding fluidity represented by MFR, and mold releasability are balanced and excellent.

Further, Comparative Example 1 in which the olefin polymer is not added is inferior in impact resistance represented by a notched Izod impact value,
The releasability was also unsatisfactory.

Further, Comparative Examples 2 and 3, which used a non-unsaturated epoxy monomer as a modifier for the unmodified olefin polymer, also had poor impact strength.

The one using ethylene / glycidyl methacrylate as the olefin polymer was inferior in molding fluidity represented by MFR and was also inferior in releasability.

In Comparative Example 5, the unmodified olefin copolymer was used, but it lacked impact resistance.

In addition, Comparative Examples 6 and 7 using a material other than the polyfunctional epoxy compound as the surface treatment agent for the glass fiber have tensile strength, elongation at break, flexural modulus and rigidity represented by flexural stress, and impact resistance. It was unsatisfactory, and the molding fluidity and releasability were also unsatisfactory.

<Effects of the Invention> The resin composition obtained by the production method of the present invention has good impact resistance and impact resistance at low temperature, and has rigidity, molding fluidity,
It has excellent releasability in balance and is useful as electric / electronic parts, automobile parts, etc.

Claims (1)

[Claims] 1. Glass fiber 3 to 200 surface-treated with 0.01 to 10% by weight of a polyfunctional epoxy compound based on (B) glass fiber based on 100 parts by weight of (A) aromatic polyester.
Parts by weight, and (C) the melt flow rate is 0.05 to 100
Of ethylene and α-olefin having 3 or more carbon atoms, or ethylene, α-olefin having 3 or more carbon atoms
Characterized by incorporating 1 to 100 parts by weight of a modified olefin copolymer obtained by graft-reacting 0.01 to 20% by weight of an unsaturated epoxy monomer with respect to a copolymer consisting of olefin and non-conjugated diene. To produce a glass fiber reinforced polyester resin composition.