JPH083012B2 - Resin composition with excellent retention heat stability - Google Patents

Description

TECHNICAL FIELD The present invention relates to a thermoplastic resin composition having excellent retention heat stability. The composition of the present invention is used for automobile parts, electricity,
It can be preferably used for electronic parts, office equipment parts, heat appliances and the like.

(Prior Art and Problems Thereof) A composition comprising a copolymer having an imide group in a side chain and one or more polymers selected from polycarbonate, polyester and polyamide has conventionally been excellent in heat resistance and mechanical properties. It is widely known that it has properties. For example, a resin composition composed of a copolymer of styrene and maleimide and a polycarbonate (US Pat. No. 4,160,792), a copolymerization product of a monomer mixture composed of styrene and maleic anhydride in the presence of a rubber block copolymer. A resin composition (US Pat. No. 4,122,130) consisting of a rubber-modified imidized copolymer obtained by reacting the combined product with ammonia and / or a primary amine and a polycarbonate, and a copolymer consisting of styrene and maleic anhydride to an ammonia and / or a An imidized copolymer reacted with a primary amine and a graft copolymer obtained by copolymerizing a monomer mixture of styrene, acrylonitrile and a vinyl monomer copolymerizable therewith in the presence of a rubbery polymer. Resin composition comprising at least one polymer selected from polycarbonate and polyester resin (JP-A-57-125241) And styrene and alpha, beta-
A resin composition (JP-A-58-71952) comprising a copolymer with an unsaturated dicarboxylic acid imide compound and a polyamide can be mentioned.

However, these compositions have the drawbacks of discoloration when the molded product is left at a high temperature, coloring when retained in the cylinder during molding, and a large decrease in mechanical properties, particularly impact strength. The thermal stability of these compositions is far inferior to that of a copolymer having an imide group or polycarbonate, polyester, or polyamide alone.

(Means for Solving the Problems) The present inventor intends to improve the discoloration resistance and residence heat stability of a resin composition comprising a copolymer having an imide group and at least one resin of polyester or polyamide. The present invention has been achieved through intensive studies for the purpose.

The present invention relates to a component A: an acid anhydride group of a copolymer containing an unsaturated dicarboxylic acid anhydride is adjusted to 40 to 90 with ammonia and / or a primary amine.
Mol% imidized rubbery polymer 0-40% by weight, aromatic vinyl monomer residue 30-88% by weight, unsaturated dicarboxylic acid imide derivative residue 10-68% by weight, unsaturated dicarboxylic acid anhydride unit 2 to 98 parts by weight of an imidized copolymer composed of 2 to 20% by weight of a monomer residue and 0 to 40% by weight of a vinyl monomer residue other than these residues, and a component B: selected from polyester and polyamide. 1
2 to 98 parts by weight of the above polymer, 40 to 80% by weight of an aromatic vinyl monomer, 0 to 40% by weight of a vinyl cyanide monomer, and 5 to 80% by weight of a C component: a rubbery polymer, and 0 to 50 parts by weight of a graft copolymer obtained by copolymerizing 20 to 95% by weight of a monomer mixture consisting of 0 to 40% by weight of a vinyl monomer copolymerizable therewith, and D component: an aromatic vinyl unit Aromatic vinyl monomer obtained by copolymerizing a monomer mixture consisting of 40 to 80% by weight of a vinyl monomer, 0 to 40% by weight of a vinyl cyanide monomer and 0 to 40% by weight of a vinyl monomer copolymerizable therewith. A thermoplastic resin composition comprising 0 to 70 parts by weight of the body.

As the method for producing the component A copolymer, an aromatic vinyl monomer, an unsaturated dicarboxylic acid anhydride and a vinyl monomer mixture copolymerizable therewith are copolymerized in the presence of a rubbery polymer, if necessary. The polymer has an acid anhydride group content of 0.
4-0.90 mol, preferably 0.5-0.9 mol, more preferably
The imidized copolymer can be obtained by a method of converting 0.6 to 0.8 molar equivalent of ammonia and / or a primary amine to convert a part of the acid anhydride group into an imide group.

Aromatic vinyl monomers used for the component A copolymer include styrene, α-methylstyrene, vinyltoluene,
It is a styrene monomer such as t-butylstyrene or chlorostyrene and a substituted monomer thereof, and among these, styrene is particularly preferable.

Examples of unsaturated dicarboxylic acid anhydrides include anhydrides such as maleic acid, itaconic acid, citraconic acid, and aconitic acid, with maleic anhydride being particularly preferred.

Examples of vinyl monomers copolymerizable with these include acrylonitrile, methacrylonitrile, vinyl cyanide monomers such as α-chloroacrylonitrile, and acrylate monomers such as methyl acrylate and ethyl acrylate. There are methacrylic acid ester monomers such as methyl methacrylic acid ester and ethyl methacrylic acid ester, acrylic acid, vinyl carboxylic acid monomers such as methacrylic acid, acrylamide, methacrylamide and the like, among which acrylonitrile, Monomers such as methacrylic acid esters, acrylic acid and methacrylic acid are preferred.

Further, the ammonia or primary amine used in the imidization reaction may be in an anhydrous or aqueous state, and examples of the primary amine include alkylamines such as methylamine, ethylamine, butylamine and cyclohexylamine, and Examples thereof include aromatic amines such as chloro- or bromo-substituted alkylamines, aniline, tolylamine and naphthylamine, and halogen-substituted aromatic amines such as chloro- or bromo-substituted aniline.

Further, when the imidization reaction is performed in a solution state or a suspension state, it is preferable to use a normal reaction vessel, for example, an autoclave, and when the imidization reaction is performed in a bulk molten state, an extruder equipped with a devolatilizer may be used. Good. Further, a catalyst may be present at the time of imidization, and for example, a tertiary amine or the like is preferably used.

The temperature of the imidization reaction is about 50 to 350 ° C, preferably 100 to 300 ° C. When the temperature is lower than 50 ° C, the reaction rate is slow and the reaction requires a long time, which is not practical. On the other hand, when the temperature exceeds 350 ° C, the physical properties are deteriorated due to thermal decomposition of the polymer.

The amount of acid anhydride residue is adjusted by the molar equivalent of ammonia and / or primary amine added to the acid anhydride group.

As the solvent for imidization in a solution state, there are acetone, methyl ethyl ketone, methylisobutyl ketone, acetophenone, tetrahydrofuran, dimethylformamide and the like. Among these, methyl ethyl ketone and methyl isobutyl ketone are preferable. The non-aqueous medium used for imidization in suspension in a non-aqueous medium includes aliphatic hydrocarbons such as heptane, hexane, pentane, octane, 2-methylpentane, cyclopentane and cyclohexane.

Further, as the rubber-like polymer, a butadiene polymer, a copolymer with a vinyl monomer copolymerizable with butadiene, an ethylene-propylene copolymer, an ethylene-propylene-diene copolymer, a block of butadiene and aromatic vinyl A copolymer, an acrylic acid ester polymer, a copolymer of an acrylic acid ester and a vinyl monomer copolymerizable with me, and the like are used.

Component A copolymer is a rubbery polymer 0-40% by weight, preferably 0-30% by weight, aromatic vinyl monomer residue 30-88% by weight, preferably 40-70% by weight, unsaturated dicarboxylic acid imide. Derivative residue 10 to 68% by weight, preferably 3 to 60% by weight, unsaturated dicarboxylic acid anhydride monomer residue 2 to 20% by weight, preferably 2 to 15% by weight, and vinyl monomer copolymerizable therewith It is an imidized copolymer composed of 0 to 40% by weight of body residue, preferably 0 to 30% by weight, and the amount of the rubber-like polymer is 40% by weight.
If it exceeds, heat resistance, moldability and dimensional stability are impaired.
When the amount of the aromatic vinyl monomer residue is less than 30% by weight, moldability and dimensional stability are impaired, and when it exceeds 88% by weight, impact strength and heat resistance are impaired. When the amount of the unsaturated dicarboxylic acid imide derivative residue is less than 10% by weight, the effect of improving the heat resistance is not sufficient, while when it exceeds 68% by weight, the resin composition becomes brittle and the moldability is significantly deteriorated.

2% by weight of unsaturated dicarboxylic acid anhydride monomer residue
If it is less than 20%, the effect of improving discoloration resistance and retention heat stability of the obtained resin composition is not observed, and if it exceeds 20% by weight, the retention heat stability of the resin composition obtained again becomes poor, which is not preferable. When the amount of the vinyl monomer residue copolymerizable with these exceeds 40% by weight, dimensional stability and heat resistance are impaired.

The unsaturated dicarboxylic acid anhydride residue in the component A of the present invention is
If it exceeds 20% by weight, the thermal stability of the A component unit is low, and the thermal stability of the resulting blended resin composition is insufficient, which results in the disadvantage that the retention thermal stability is also reduced. When the unsaturated dicarboxylic acid anhydride content in the component A is 2 to 20% by weight, the thermal stability of the component A alone is not sufficiently good, but the thermal stability of the resulting blended resin composition is extremely good. It is possible to obtain a resin composition that is specifically excellent in discoloration resistance and retention heat stability. 2% by weight of unsaturated dicarboxylic acid anhydride residue
If it is less than 1, the thermal stability of the component A is good, but
Conversely, the thermal stability of the resulting blended resin composition decreases,
Disadvantages of deterioration in discoloration resistance and residence heat stability appear.

Next, as the polyester which can be used as the component B, terephthalic acid, adipic acid, sebacic acid, isophthalic acid,
Dicarboxylic acids such as naphthalenedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid, or dimethyl terephthalate, diethyl terephthalate, and dicarboxylic acid derivatives such as dimethyl 1,4-cyclohexanedicarboxylic acid and ethylene glycol, 1,3-propylenediol, It is a polymer having an ester bond, which is synthesized from diol compounds such as 1,4-butanediol and poly (tetramethylene oxide) glycol. Further, different dicarboxylic acids and their derivatives and different diol compounds are used as raw materials. Polyester may be used as well.

Polyamides that can be used as the component B include nylon-6, nylon-6,6, nylon-6,10, nylon-11, nylon-12, a copolymer of terephthalic acid and trimethylhexamethylenediamine, and an aliphatic dicarboxylic acid. A copolymer of acid and xylylenediamine, a polyether amide or a polyether ester amide which is a block copolymer having a polyether as a soft segment and a polyester amide or a polyamide as a hard segment.

The composition of the present invention contains at least one polymer selected from these polyesters and polyamides as an essential component, but may of course contain two or more polymers.

Next, the C component and its manufacturing method will be described. The rubber-like polymer used in the component C is butadiene homopolymer or a polymer composed of vinyl monomer copolymerizable therewith, ethylene-propylene-diene copolymer or acrylic acid ester homopolymer or vinyl monomer copolymerizable therewith. There are polymers that consist of polymers.

Aromatic vinyl monomer of C component is styrene, α-
It is a styrene monomer such as methylstyrene, vinyltoluene, t-butylstyrene, chlorostyrene or a substituted monomer thereof, and among them, monomers such as styrene and α-methylstyrene are particularly preferable.

Examples of the vinyl cyanide monomer include acrylonitrile, methacrylonitrile, α-chloroacrylonitrile and the like, and acrylonitrile is particularly preferable. Examples of vinyl monomers copolymerizable with them include acrylic acid ester monomers such as methyl acrylic acid ester, ethyl acrylic acid ester and butyl acrylic acid ester, and methacrylic acid ester such as methyl methacrylic acid ester and ethyl methacrylic acid ester. Examples thereof include monomers, vinylcarboxylic acid monomers such as acrylic acid and methacrylic acid, acrylic acid amides, methacrylic acid amides, acenaphthylene and N-vinylcarbazole. Of these, methyl methacrylic acid ester, acrylic acid and methacrylic acid are particularly preferable.

The method for producing the C component graft copolymer is 5
From 40 to 80% by weight of an aromatic vinyl monomer, 0 to 40% by weight of a vinyl cyanide monomer in the presence of 80% by weight, and 0 to 40% by weight of a vinyl monomer copolymerizable therewith, if necessary. It is obtained by graft-copolymerizing 20 to 95% by weight of the following monomer mixture. For the polymerization, any known polymerization technique can be adopted, for example, suspension polymerization, aqueous heterogeneous polymerization such as emulsion polymerization,
Bulk polymerization, solution polymerization, precipitation polymerization of the produced polymer in a non-solvent, and the like.

The aromatic vinyl monomer used as the component D is a styrene monomer such as styrene, α-methylstyrene, vinyltoluene, t-butylstyrene, chlorostyrene, or a substituted monomer thereof. And α
Monomers such as methylstyrene are particularly preferred.

Examples of the vinyl cyanide monomer include acrylonitrile, methacrylonitrile, α-chloroacrylonitrile and the like, and acrylonitrile is particularly preferable. As vinyl monomers copolymerizable with these, acrylic acid esters such as methyl acrylic acid ester, ethyl acrylic acid ester and butyl acrylic acid ester, and methacrylic acid ester monomers such as methyl methacrylic acid ester and ethyl methacrylic acid ester. , Vinyl carboxylic acid monomers such as acrylic acid and methacrylic acid, acrylic acid amides, and methacrylic acid amides. Of these, methyl methacrylic acid ester, acrylic acid and methacrylic acid are particularly preferable.

In the present invention, the ratio of blending each of the components A, B, C and D is 2 to 98 parts by weight, preferably 10 to 90 parts by weight, and 2 to 98 parts by weight, preferably 10 parts by weight, for the B component. -90 parts by weight, 0 to 50 parts by weight of C component, preferably 0
˜35 parts by weight, component D is 0 to 70 parts by weight, preferably 0 to 50 parts by weight. When the ratio of the component A is less than 2 parts by weight,
The heat resistance is insufficient, and if it exceeds 98 parts by weight, the impact strength decreases. If the proportion of the component B is less than 2 parts by weight, either the falling weight impact strength or the fluidity is impaired, and if it exceeds 98 parts by weight,
There are disadvantages that the hot water resistance is lowered and the mechanical properties and dimensions are largely changed by moisture absorption. By including the C component, the impact strength is improved, but if it exceeds 50 parts by weight,
Heat resistance and fluidity are reduced. Further, the fluidity is improved by including the component D, but if it exceeds 70% by weight, there is a drawback that heat resistance and impact strength are lowered.

The method for blending the resin composition of the present invention is not particularly limited, and known means can be used. Examples of the means include a Banbury mixer, a tumbler mixer, a Henschel mixer, a mixing roll, a single-screw or twin-screw extruder, and the like. As a mixing form, there are methods such as ordinary melt mixing, multistage melt kneading using master pellets and the like, solution blending, mixing in a reaction liquid and the like to obtain a composition.

Further, the composition of the present invention further comprises a polyether sulfone,
Resins such as polyetherketone and polyphenylene sulfide, stabilizers, flame retardants, plasticizers, lubricants, antistatic agents, UV absorbers, colorants and talc, silica, clay, mica, glass fiber, fillers such as calcium carbonate, and It is also possible to add a conductive material such as carbon fiber or silver powder.

Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded. All parts and% in the examples are expressed on a weight basis.

(Examples of the Invention) Experimental Example 1 Production of Component A (A-1 to A-5) 60 parts of styrene, 100 parts of methyl ethyl ketone, and 10 parts of polybutadiene cut into small pieces were charged into an autoclave equipped with a stirrer. After stirring at room temperature for one day to dissolve the rubber, the system was replaced with nitrogen gas and the temperature was raised to 85 ° C.
A solution prepared by dissolving 40 parts of maleic anhydride and 0.15 part of benzoyl peroxide in 250 parts of methyl ethyl ketone was continuously added over 8 hours. The temperature was maintained at 85 ° C for a further 3 hours after the addition. A part of the viscous reaction liquid was sampled and the amount of unreacted monomer was quantified by gas chromatography. As a result, the polymerization rates were 98% for styrene and 98% for maleic anhydride. To the obtained copolymer solution, 0.3 parts of aniline or methylamine and the equivalent of triethylamine shown in Table 1 to maleic anhydride were added and reacted at 140 ° C. for 7 hours. The reaction solution was taken out in a vat, vacuum dried and pulverized to obtain imidized copolymer pairs A-1 to A-5. Table 1 shows the results of evaluating the thermal stability of the imidized copolymers A-1 to A-5 by a thermobalance.

Experimental Example 2 Production of C Component (Graft Copolymerization) (C-1) 80 parts of polybutadiene latex (solid content 50%, average particle size 0.35 μ, gel content 90%), sodium stearate 1
Part, sodium formaldehyde sulfoxylate 0.1
Parts, tetrasodium ethylenediaminetetraacetic acid 0.03 parts, ferrous sulfate 0.003 parts and water 200 parts were charged in an autoclave replaced with nitrogen gas. Temperature 65
After heating to ℃ 30% acrylonitrile and styrene
60% of monomer mixture consisting of 70%, 0.3 part of t-dodecyl mercaptan, 0.2 part of Kyumen Hyde peroxide 4 parts
After the addition was completed, polymerization was continued for 2 hours at 65 ° C. The polymerization rate was 96%. After adding an antioxidant to the obtained latex, it was salted out with calcium chloride, washed with water and dried to obtain a white powdery polymer C-1.

Experimental Example 3 Production of D component (D-1) 70 parts of α-methylstyrene, 30 parts of acrylonitrile, 2.5 parts of sodium stearate, 0.6 part of t-dodecyl mercaptan
Parts and 250 parts of water were heated to 70 ° C., and 0.05 part of potassium persulfate was added thereto to initiate polymerization. After 5 hours from the start of polymerization, 0.03 part of potassium persulfate was added and the temperature was raised to 75 ° C.
The temperature was raised to and maintained for 3 hours to complete the polymerization. Polymerization rate is 97
% Has been reached. The obtained latex was coagulated with calcium chloride, washed with water and dried to obtain a white powdery copolymer. This was designated as Copolymer D-1.

Experimental Example 4 Evaluation of physical properties of resin composition As component A, imidized copolymers of A-1 to A-5, and B
Nylon 6 as an ingredient (Ube nylon 10 manufactured by Ube Industries, Ltd.)
13B), polybutylene terephthalate (Duranex 2002 manufactured by Polyplastics Co., Ltd.) or polyester elastomer (Perprene P70B manufactured by Toyobo Co., Ltd.), C-1 as the C component and D-1 as the D component are blended at the ratios shown in Table 2. The blend was extruded with a 30 mmφ devolatilizer screw extruder to form pellets. Each of the blends contained 0.2 parts of octadecyl-3- (3,5-ditersialybutyl-4-hydroxyphenyl) -pyropionate (antioxidant). The physical properties of the composition thus obtained were measured and the results are also shown in Table 2.

 The physical properties were measured by the following methods.

(1) Vicat softening point (VSP): Measured according to ASTM D-1522 with a load of 5 kg.

(2) Impact strength of normal molding: Notched Izod impact strength was measured according to ASTM D-256. The test piece was molded at a cylinder temperature of 210 ° C. and a mold clamping time of 45 seconds.

(3) Impact strength during retention molding: Notched Izod impact strength was measured according to ASTM D-256. The test piece was molded at a cylinder temperature of 270 ° C. and a mold clamping time of 180 seconds.

(4) Thermal stability: Indicates the temperature when the weight loss of the imidized copolymer and the resin composition is 5% in the thermobalance analysis under the conditions of a nitrogen gas flow of 50 cc / min and a heating rate of 10 ° C./min.

(5) Discoloration resistance: The molded product was left standing at 120 ° C. for 3 hours while the gear was open and visually evaluated.

(Effects of the Invention) An imidized copolymer obtained by imidizing an acid anhydride group of an unsaturated dicarboxylic acid anhydride copolymer with ammonia and / or a primary amine in an amount of 40 to 90 mol%, polyester or polyamide is selected. In the resin composition containing one or more polymers as essential components, a resin composition having excellent retention heat stability and excellent discoloration resistance, and excellent heat resistance and impact strength was obtained.

Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location C08L 51/06 LKY 67/02 LPB 77/00 LQS

Claims (1)

[Claims] 1. A component: 0 to 40 parts by weight of a rubber-like polymer obtained by imidizing the acid anhydride group of a copolymer containing an unsaturated dicarboxylic acid anhydride with ammonia and / or a primary amine in an amount of 40 to 90 mol%. %, Aromatic vinyl monomer residues 30 to 88% by weight, unsaturated dicarboxylic acid imide derivative residues 10 to 68% by weight, unsaturated dicarboxylic acid anhydride monomer residues 2 to 20% by weight, and residues thereof. 2 to 98 parts by weight of an imidized copolymer composed of 0 to 40% by weight of a vinyl monomer residue other than the group, and B component: 1 selected from polyester and polyamide
2 to 98 parts by weight of at least one polymer, and C component: 5 to 80% by weight of a rubber-like polymer, 40 to 80% by weight of an aromatic vinyl monomer, 0 to 40% by weight of a vinyl cyanide monomer. And 0 to 50 parts by weight of a graft copolymer obtained by copolymerizing 20 to 95% by weight of a monomer mixture consisting of 0 to 40% by weight of a vinyl monomer copolymerizable therewith, and D component: an aromatic vinyl monomer. Aromatic vinyl copolymer obtained by copolymerizing a monomer mixture comprising 40 to 80% by weight of a monomer, 0 to 40% by weight of a vinyl cyanide monomer and 0 to 40% by weight of a vinyl monomer copolymerizable therewith. A thermoplastic resin composition comprising 0 to 70 parts by weight of a polymer.