JPH02142842A - Molded part of information processing machine - Google Patents

Abstract

PURPOSE:To obtain the title part improved in dimensional stability, heat resistance, mechanical strengths and moldability by molding a thermoplastic polymer composition comprising specified block copolymer, polyphenylene ether and vinylaromatic hydrocarbon polymer. CONSTITUTION:100 pts.wt. total of 10-95 pts.wt. block copolymer (A) comprising at least two polymer segments of a number-average MW of 5000-500000 containing 60-95wt.% vinylaromatic hydrocarbon and at least one polymer segment of a number-average MW of 1000-400000 based on a conjugated diene and 90-5 pts.wt. polyphenylene ether (B) of a number-average degree of polymerization of 50-500 is mixed with 2-500 pts.wt. vinylaromatic hydrocarbon polymer (C) (e.g., PS) to obtain a thermoplastic polymer composition of a melt flow rate (JIS K-6870, at 200 deg.C under a load of 5kg) of 0.001-70g/10min. This composition is molded into any desired shape to obtain a molded part of an information processing machine.

Description

Detailed Description of the Invention <Industrial Application Field> The present invention relates to a block copolymer comprising a vinyl aromatic hydrocarbon and a conjugated diene, a polyphenylene ether resin, and a thermoplastic polymer comprising a vinyl aromatic hydrocarbon polymer. The present invention relates to a plastic molded article for information equipment parts made of a combined composition.

<Conventional technology and its problems> Conventionally, parts of information equipment or information processing equipment such as word processors, facsimiles, copiers, printers, etc. have been made using aluminum die-casting, aluminum cuttings, unsaturated polyester resin by hand lay-up method, or RIM method.・Hard urethane made by casting was used, but with the recent spread of various information devices, the proportion of information device parts using thermoplastic plastics, which can be easily mass-produced, is increasing.

In addition, there is a growing demand for these information devices to be smaller and lighter, better designed, and more decorative through colorization, and improvements are needed in the dimensional stability, heat resistance, mechanical strength, moldability, appearance, etc. of plastic molded products. is required even more. Various plastics have been used to meet these requirements, but non-grade plastics generally have insufficient heat resistance, while crystalline plastics have the disadvantage of insufficient dimensional stability.

<Means for Solving the Problems> As a result of intensive studies to improve these drawbacks, the present inventors found that block copolymers with a high vinyl aromatic hydrocarbon content, polyphenylene ether, and vinyl aromatic hydrocarbon-based The present invention was completed based on the discovery that a molded product satisfying the above-mentioned performance requirements could be obtained by combining polymers.

That is, the present invention provides: (a) consisting of at least two polymer segments mainly composed of vinyl aromatic hydrocarbons and at least one polymer segment mainly composed of conjugated dienes, the vinyl aromatic hydrocarbon content being is more than 60% by weight and not more than 95% by weight 10~
95 parts by weight (b) Polyphenylene ether 5~
90i 1 part (C) Vinyl aromatic hydrocarbon polymer Information equipment parts made of a thermoplastic polymer composition consisting of 2 to 500 parts by weight based on 100 parts by weight of the above component (a) and component (b). Regarding molded objects.

The present invention will be explained in detail below.

The block copolymer of component (a) used in the present invention consists of at least two polymer segments mainly composed of vinyl aromatic hydrocarbons and at least one polymer segment mainly composed of conjugated dienes, Vinyl aromatic hydrocarbon content is more than 60% by weight and not more than 95% by weight, preferably 6% by weight
It is 5 to 90% by weight.

If the vinyl aromatic hydrocarbon content is less than 60% by weight, the surface hardness, heat resistance, and gloss will be poor, and if it exceeds 95% by weight, the impact resistance will be poor, which is not preferable.

In the present invention, a polymer segment mainly containing vinyl aromatic hydrocarbons is a polymer segment containing vinyl aromatic hydrocarbons in an amount of 50% by weight or more, preferably 70% by weight or more. A segment composed of a copolymer block of hydrogen and a conjugated diene and a vinyl aromatic or aromatic hydrocarbon homopolymer block, or a segment composed of a vinyl aromatic hydrocarbon homopolymer block. Further, a polymer segment mainly containing a conjugated diene is a polymer segment in which the content of conjugated diene is more than 50% by weight, preferably 70% by weight or more,
A segment composed of a copolymer block of a conjugated diene and a vinyl aromatic hydrocarbon and/or a conjugated diene homopolymer block. The vinyl aromatic hydrocarbon copolymerized in the copolymer blocks in these segments may be uniformly distributed or tapered. Further, the copolymer block may coexist with a plurality of portions where vinyl aromatic hydrocarbons are uniformly distributed and/or portions where vinyl aromatic hydrocarbons are distributed in a tapered shape.

The block copolymer of component (a) used in the present invention has a polymer structure of the following general formula: (A-B), l, A(-B-A), l, B-G-A
-B), l (In the above formula, A is a polymer block mainly composed of vinyl aromatic hydrocarbons, and B is a polymer block mainly composed of conjugated diene. The boundary between A block and B block do not necessarily need to be clearly distinguished. Also, n is an integer of 1 or more, preferably an integer of 1 to 5.

) or the general formula % formula % (In the above formula, A and B are the same as above, and X is, for example, silicon tetrachloride, tin tetrachloride, epoxidized soybean oil,
Indicates the residue of a coupling agent such as a polyhalogenated hydrocarbon, a carboxylic acid ester, or a polyvinyl compound, or the residue of an initiator such as a polyfunctional organolithium compound. m and n are 1
or more, preferably m is an integer of 1 to 10, and n is 1 to
It is an integer of 5. ) can be used. The block copolymer used in the present invention may be any mixture of block copolymers represented by the above general formula.

Vinyl aromatic hydrocarbons used in the method of the present invention include styrene, 0-methylstyrene, p-methylstyrene, p-methylstyrene,
Examples include -tert-butylstyrene, (1), 3-dimethylstyrene, α-methylstyrene, vinylnaphthalene, vinylanthracene, and styrene is particularly common. These may be used not only alone, but also as a mixture of two or more.

The conjugated diene used in the present invention is a diolefin having a pair of conjugated double bonds, such as 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl- 1,3-butadiene, 1.
Examples include 3-pentadiene and 1,3-hexadiene, and particularly common ones include 1,3-butadiene and isoprene. These may be used not only alone, but also as a mixture of two or more.

The block copolymer used in the present invention is prepared in a hydrocarbon solvent.
Obtained by polymerization using an organic lithium compound as an initiator.

Examples of hydrocarbon solvents include aliphatic hydrocarbons such as butane, pentane, hexane, isopentane, heptane, octane, and isooctane; alicyclic hydrocarbons such as cyclopenkune, methylcyclopentane, cyclohexane, methylcyclohexane, and ethylcyclohexane; or benzene and toluene. , ethylbenzene, xylene, and other aromatic hydrocarbons. Organolithium compounds have 1 in the molecule.
It is an organic lithium compound in which more than one lithium atom is combined, such as ethyllithium, n-propyllithium,
Isopropyllithium, n-butyllithium, 5ec-
Examples include butyl lithium, tert-butyl lithium, hexamethylene dilithium, butadienyl dilithium, isoprenyl dilithium, and the like.

In the block copolymer of component (a) used in the present invention, the number average molecular weight of segment I-A is 5,000 to 50.
0.000, preferably 70,000 to 300.00
0, and the number average molecular weight of segment B is 1,000
~400,000, preferably 3.000-300.0
It is 00. The number average molecular weight of the block copolymer as a whole is 10,000 to 1.000,000, preferably 30.000 to 500.000.

A particularly preferable block copolymer in the present invention is a block copolymer of component (a) used in the present invention, in which a vinyl aromatic hydrocarbon polymer block is present in the copolymer as a vinyl aromatic hydrocarbon polymer block. The proportion of hydrocarbons to the total vinyl aromatic hydrocarbons contained in the copolymer (hereinafter referred to as the block rate of vinyl aromatic hydrocarbons) is 75% by weight.
more than 98% by weight, preferably 77-96% by weight
It is a block copolymer of When the block rate of vinyl aromatic hydrocarbon is less than 75% by weight, surface hardness and heat resistance tend to decrease, and when it exceeds 98% by weight, impact resistance tends to decrease. The block rate of vinyl aromatic hydrocarbons can be determined by a method of oxidative decomposition of the copolymer with di-tert-butyl hydroperoxide using osmium tetroxide as a catalyst (for example, L, M, K
olthoff et al., J. Polymer
Sc+, 1.429 (1946)). That is, after oxidatively decomposing a block copolymer by the above method, a large amount of methanol is added to the decomposed product to obtain a vinyl aromatic hydrocarbon polymer component (generally having a number average molecular weight of about 1000 or more, usually about 3000).
to about 1,000,000) by the total amount of vinyl aromatic hydrocarbons contained in the block copolymer to determine the block rate of vinyl aromatic hydrocarbons.

In addition, the block copolymer of component (a) used in the present invention has a weight average molecular weight (hereinafter referred to as Mw) and a number average molecular weight (hereinafter referred to as Mw) of the vinyl aromatic hydrocarbon polymer block in the copolymer.
The overall ratio of Mn (hereinafter referred to as Mn) is preferably in the range of 1.2 to 2.0, preferably 1.3 to 1.8. M
When the w/Mn ratio is less than 1.2, impact resistance tends to decrease, and when it exceeds 2.0, molding anisotropy occurs and the molded product tends to warp. Become. Mw/Mn of the vinyl aromatic hydrocarbon polymer block in the block copolymer can be measured as follows. The vinyl aromatic hydrocarbon polymer component obtained by oxidative decomposition of the block copolymer by the above method is measured by gel permeation chromatography (GPC), It can be calculated according to the method described in 〉” published by Kodansha.

The calibration curve for GPC is prepared using standard polystyrene commercially available for GPC.

A particularly preferable block copolymer as the component (a) used in the present invention is a glass transition temperature (
It is a block copolymer having a Tg) of 65 to 98°C, preferably 75 to 96°C. When a block copolymer having a Tg in this range is used, a composition with less occurrence of micro-cracks when the composition is bent can be obtained. still,
The Tg referred to here is the temperature determined from the inflection point of the dynamic viscoelastic modulus (E') in the measurement of dynamic viscoelasticity, or the inflection point of temperature change in a differential scanning calorimeter (DSC). Says temperature.

Dynamic viscoelasticity can be measured using a Rheopybron (Model DDV-3) manufactured by Toyo Baldwin.

As the block copolymer used in the present invention, a block copolymer in which a polar group-containing atomic group is bonded to at least one polymer chain terminal can be used. Here, the polar group-containing atomic groups include nitrogen, oxygen, silicon, phosphorus, sulfur,
An atomic group containing at least one atom selected from tin. Specifically, carboxyl group, carbonyl group,
Thiocarbonyl group, acid halide group, acid anhydride group, carboxylic acid group, thiocarboxylic acid group, aldehyde group, thousand oaldehyde group, carboxylic acid ester group, amide group, sulfonic acid group, sulfonic acid ester group, phosphoric acid group , phosphate ester group, amino group, imino group, nitrile group, pyridyl group, quinoline group, epoxy group, thioepoxy group, sulfide group, isocyanate group, isothioneanate group, silicon halide group, alkoxy silicon group, tin halide Examples include atomic groups containing at least one polar group selected from the group consisting of alkyltin groups, alkyltin groups, phenyltin groups, and the like. More specifically, the terminal-modified block copolymer described in Japanese Patent Application No. 60-224806 can be used.

In the present invention, a hydrogenated product of the above-mentioned block copolymer or terminal-modified block copolymer can be used. Catalysts used in the hydrogenation reaction include (1) Ni;
Metals such as Pt, Pd, and Ru are combined with carbon, silica,
The so-called Ziegler method uses a supported heterogeneous catalyst supported on a carrier such as alumina or diatomaceous earth, (2) an organic acid salt such as Ni, Co, Fe, or Cr, or an acetylatonate salt, and a reducing agent such as organic AP. type catalyst, or Ru
Homogeneous catalysts such as so-called organic complex catalysts such as organometallic compounds such as , Rh, etc. are known. Specific methods include Japanese Patent Publication No. 42-8704, Japanese Patent Publication No. 436636,
Or JP-A-59-133203, JP-A-60
According to the method described in JP-A-220147, hydrogenation is performed in an inert solvent in the presence of a hydrogenation catalyst to obtain a hydrogenated product, and the hydrogenated polymer used in the present invention can be synthesized. At that time, the hydrogenation rate of aliphatic double bonds based on the conjugated diene compound in the polymer can be controlled to any value by adjusting the reaction temperature, reaction time, hydrogen supply amount, catalyst amount, etc.

For example, when improving heat deterioration resistance etc. while maintaining the properties of an unhydrogenated polymer, the aliphatic double bonds based on conjugated diene should be less than 3%, less than 80%, preferably 5% or more,
Hydrogenation of less than 5%, particularly preferably 10 to 45%, or 80% in order to improve heat deterioration resistance and weather resistance.
As mentioned above, it is recommended to hydrogenate preferably 90% or more. In this case, the aromatic double bond based on the vinyl aromatic compound copolymerized into the polymer block A mainly composed of a vinyl aromatic compound and, if necessary, the polymer block B mainly composed of a conjugated diene compound. Although there is no particular restriction on the addition rate, it is preferable that the hydrogenation rate is 20% or less. The amount of unhydrogenated aliphatic double bonds contained in the hydrogenated block copolymer can be easily determined using an infrared spectrometer, nuclear magnetic resonance apparatus, or the like.

Next, the polyphenylene ether of the component used in the present invention has a general formula: The remaining alkyl group, aryl group, and halogen atoms in 4 are hydrogen atoms, which may be the same or different from each other. The repeating unit represented by (I) and the general formula (R3 in the formula
, R4, R5 and R6 are each a linear, secondary or secondary branched alkyl group having 1 to 4 carbon atoms, an aryl group, a halogen atom, a hydrogen atom, etc., and these are the same or may be different from each other, but R3 and R4 cannot be hydrogen atoms at the same time); homopolymers and copolymers thereof; These include graft copolymers in which styrene is graft-polymerized.

Representative examples of homopolymers of polyphenylene ether include poly(2,6-dimethyl-1,4-phenylene) ether, poly(2-methyl-6-ethyl-1,4-phenylene) ether, and poly(2,6-dimethyl-1,4-phenylene) ether. -diethyl-1,
4-phenylene)ether, poly(2-ethyl-6-
n-propyl-1,4-phenylene) ether. Poly
(2,6-di-n-propyl-1,4-phenylene) ether, poly(2-methyl-6-n-butyl-1,4-phenylene) ether, poly(2-ethyl-6-isopropyl-1) ,4-phenylene)ether, poly(2-
Methyl-6-chloro1,4-phenylene) ether, poly(2-methyl-6hydroxyethyl-1,4-phenylene) ether, poly(2-methyl-6-chloroethyl-1,4-phenylene) ether, etc. Examples include homopolymers.

The polyphenylene ether copolymer is an alkyl phenol such as 0-cresol or 2,3.6-) lynchylphenol represented by the general formula (R, l, Ra, R5 and R6 in the formula have the same meanings as above). It includes a polyphenylene ether copolymer mainly having a polyphenylene ether structure obtained by copolymerizing with a substituted phenol.

The number average degree of polymerization (n) of polyphenylene ether is 50
-500, preferably 75-250. If the number average degree of polymerization is less than 50, the physical properties of the resulting composition, such as impact strength, will significantly deteriorate and it will be difficult to put it to practical use. 50 again
If it exceeds 0, the processing fluidity of the obtained composition will be poor and gelation will occur easily, which is undesirable.

The polyphenylene ether used in the present invention may be a modified polyphenylene ether obtained by adding and/or graft polymerizing a radically polymerizable vinyl compound to the above homopolymer or copolymer. Examples of vinyl compounds include the above-mentioned vinyl aromatic hydrocarbons, halogen-substituted products thereof, unsaturated monocarboxylic acid esters such as acrylic acid esters and methacrylic acid esters, and unsaturated carboxylic acid amides such as acrylamide and methacrylic acid amide. , unsaturated dicarboxylic acids such as maleic acid, fumaric acid, and itaconic acid, acid anhydrides, esters, amides, imides, and nitrile monomers such as acrylonitrile and methacrylonitrile of these unsaturated dicarboxylic acids.

The vinyl aromatic hydrocarbon polymer as component (C) used in the present invention is a polymer of the above vinyl aromatic hydrocarbon or a copolymer with a vinyl compound copolymerizable with the above vinyl aromatic hydrocarbon. It is a combination. The above-mentioned vinyl compounds can be used as the copolymerizable polymer. Preferred (co)polymers as component (C) are polystyrene, styrene-
Examples include α-methylstyrene copolymer, acrylonitrile-styrene copolymer, styrene-methacrylic acid ester copolymer, styrene-maleic anhydride copolymer, etc., and these may be used alone or as a mixture of two or more. Can be done. These (co)polymers are effective in further improving the surface hardness and rigidity of the composition.

Incidentally, in the present invention, a rubber-modified vinyl aromatic hydrocarbon polymer (hereinafter referred to as component (d)) can be blended. The rubber-modified vinyl aromatic hydrocarbon polymer is obtained by polymerizing a mixture of the vinyl aromatic hydrocarbon or a monomer copolymerizable therewith with an elastomer, and polymerization methods include suspension polymerization, emulsion polymerization, Bulk polymerization, bulk suspension polymerization, etc. are generally carried out. Monomers copolymerizable with vinyl aromatic hydrocarbons include α
- Examples include the above-mentioned vinyl compounds such as methylstyrene, acrylonitrile, acrylic esters, methacrylic esters, and maleic anhydride. In addition, as elastomers, natural rubber, synthetic isoprene rubber, butadiene rubber,
Styrene-butadiene rubber, high styrene rubber, polybutadiene rubber, chloroprene rubber, polybutene rubber, rubbery ethylene-propylene copolymer, rubbery butadiene-acrylonitrile copolymer, butyl rubber, various nitrile rubbers, rubbery ethylene-vinyl acetate Copolymers, rubbery ethylene-acrylic acid ester copolymers, rubbery active polypropylene resins, rubbery ethylene-acrylic acid ionomers, and the like are used.

These elastomers are generally 2 to 70 parts by weight, more typically 3 to 50 parts by weight, per 100 parts by weight of vinyl aromatic hydrocarbon or copolymerizable elastomer, or in latex. It is subjected to bulk polymerization, bulk-suspension polymerization, emulsion polymerization, etc.

Particularly preferred rubber-modified polymers include impact-resistant rubber-modified styrene polymers, acrylonitrile butadiene-styrene copolymers, acrylic ester-butadiene-styrene copolymers, methacrylic ester-butadiene-styrene copolymers, and resistant rubber-modified styrene polymers. Examples include impact rubber-modified styrene-maleic anhydride copolymers, and these can be used alone or as a mixture of two or more.

In the present invention, the blending weight ratio of component (a) and component (b) is such that component (a) is 10 to 95% by weight, preferably 20 to 95% by weight.
85% by weight, more preferably 30-80% by weight.

If component (a) is less than 10% by weight, the impact resistance and processability will be poor, and if it exceeds 95% by weight, the heat resistance and surface hardness will be poor, which is not preferable. A particularly preferable blending weight ratio is 35 to 75% by weight of component (a), and within this range, the composition has impact strength superior to that of each of component (a) and component (b) alone. A completely unexpected action and effect is realized.

In addition, in the present invention, the blending amount of component (C) is as follows: component (a)
and 2 to 500 parts by weight per 100 parts by weight of the total amount of component (b).
The amount is preferably 5 to 400 parts by weight, more preferably 10 to 300 parts by weight. If the amount of component (C) is less than 2 parts by weight, processability will be poor, and if it exceeds 500 parts by weight, impact resistance and heat resistance will decrease, which is not preferable.

Furthermore, in the present invention, the above-mentioned components may be added in an amount of 500 parts by weight or less, preferably 3 to 400 parts by weight, more preferably 5 to 300 parts by weight, based on 100 parts by weight of the composition consisting of component (a) and component (b). The impact resistance can be improved by blending component (d). If the amount of component (d) exceeds 500 parts by weight, the heat resistance will decrease, which is not preferable. still,
In order to obtain a composition with good transparency, it is recommended that the amount of component (d) is 50 parts by weight or less, preferably 25 parts by weight or less.

In addition, in the present invention, the thermoplastic polymer composition consisting of components (a), (b) and (C) conforms to JIS K-6870.
The melt flow (200°C, 5 kg load) measured according to
1 to 50 g/10 minutes, more preferably 0.1 to 30 g/10 minutes
A molding time of 10 minutes is preferable from the viewpoint of moldability.

Other thermoplastic resins and rubber-like polymers can be blended into the thermoplastic polymer composition used in the present invention. Thermoplastic resins include polyethylene, a copolymer of ethylene containing 50% or more of ethylene and other monomers that can be copolymerized with it, polypropylene, propylene that contains 50% or more of propylene and copolymerizable with this. Copolymers with Chizuma, polybutene resins, polyvinyl chloride resins, polyvinyl acetate resins and their hydrolysates, polyacrylate resins, acrylonitrile resins, polyamide resins, polyester resins, polyphenylene sulfide resins Resin, polyacecool resin, polycarbonate resin, polysulfone resin, thermoplastic polyurethane resin, polybutadiene resin, polyacrylate resin,
Examples include fluororesins, polyoxybenzoyl resins, and polyimide resins. Further, as the rubbery polymer, polybutadiene, polyisoprene, styrene-butadiene copolymer, butadiene-acrylonitrile copolymer,
Ethylene-propylene copolymer, ethylene-propylene copolymer, ethylene-propylene-diene copolymer, silicone rubber, epichlorohydrin rubber, acrylic rubber,
Examples include ethylene-vinyl acetate copolymer.

The thermoplastic polymer composition used in the present invention can contain any additives, if necessary.

The type of additive is not particularly limited as long as it is commonly used in plastic formulations, but examples include glass fiber,
Inorganic reinforcing agents such as glass peas, silica, charcoal, talc, organic fibers, organic reinforcing agents such as coumaron indene resin, crosslinking agents such as organic peroxide and inorganic peroxide, titanium white, carbon black, iron oxide, etc. pigment,
Examples include dyes, flame retardants, antioxidants, ultraviolet absorbers, antistatic agents, lubricants, plasticizers, other fillers, and mixtures thereof.

The thermoplastic polymer composition used in the present invention can be manufactured by any conventional compounding method. For example, melt-kneading methods using general kneading machines such as open rolls, intensive mixers, internal mixers, co-kneader continuous kneaders with twin-screw rotors, extruders, etc., and hardening agents after dissolving or dispersing each component in a solvent. A method of removing the particles by heating is used.

Examples of information equipment parts in the present invention include parts for information storage and processing equipment such as word processors, facsimiles, copying machines, printers, typewriters, office computers, personal computers, and minicomputers, as well as magnetic tapes for recording and audio recording, ICs, etc. Examples include information storage/processing body storage containers and/or container parts, information storage/processing cards such as magnetic cards, and IC cards.

Typical molded bodies for these information equipment parts include the following. Molded parts of word processors include exterior housings, operation panels, key tops, switches, lever holders, sensor holders,
Examples include covers such as paper guides, platelet holders, sliders, chassis 1 see-through windows, soundproof covers, and protective covers. As a molded body for facsimile parts,
Covers include exterior covers, switch buttons, panels, chassis Spencer guides, receiver frames, transmitter frames, recording paper boxes, see-through windows, soundproof covers, protective covers, etc. As a molded body for copying machine parts,
Covers such as the top cover, front/left/right control covers, document holder cover, internal cover, front cover, operation surface cover, soundproof cover/protective cover, display panel, bulletin board buttons,
Control panel, photoconductor flange, cleaning machine housing, collected developer storage bottle, developer reinforcement box, handle, rail for removal/detachment, toner box lid, lens housing, light shielding plate, quick-holding plate, charging insulator , shield, paper storage box, paper storage box cover, paper guide, copy paper tray, chute, frame, etc. The molded parts of the printer include the upper and lower exterior housings,
Covers such as display panels, cassette housings, cassette covers, cassette guides, paper covers, paper guides, hammer covers, lock lever knobs, selection levers, platen knobs, carriages, carriage bases, printer bodies, see-through windows, soundproof covers, protective covers, etc. Examples include the following. Molded parts of typewriter parts include knob caps, knobs, plantain gears, carriage retaining pins, paper ball levers, flight cables, word adjustment levers, paper guides, hammer covers, lock lever knobs, collection levers, Tape guide, ribbon holding plate, wheel guide, ribbon motor frame, ribbon winding shaft, daisy protector, carriage transfer device, run feed gear, hood housing, soundproof cover/protective cover/
Covers such as switch box covers, brand badges, model badges, paper guides, indicators
Examples include top cover forceps, eraser tables, check connector lids, operation panels, key tops, see-through windows, etc. Examples of molded parts of office computer parts include covers for main parts, printer covers, CRT covers, protective covers, gate guide plates, louvers, KB cases, fans, see-through windows, and the like. Molded parts of personal computers and minicomputers include main parts housing covers, CR
Examples include covers such as T-covers, storage storage unit housing covers, protective covers, keyboard cases, fans, terminal boards, floppy slots, knobs, relays, knobs, holders, connectors, transparent windows, etc. Among the above-mentioned equipment parts, particularly suitable molded bodies in the present invention are covers such as soundproof covers and protective covers, see-through windows, paper storage boxes, paper storage box covers, paper receivers, guides, frames, and magnetic tape storage containers. , IC storage containers, and other molded objects that require transparency.

As a method for obtaining the molded article of the information device component of the present invention from the thermoplastic polymer composition, any conventionally known molding method can be applied, including injection molding, extrusion molding, blow molding, calendering, lamination molding, and vacuum molding. Molding, pressure forming, foam processing, film processing, etc. can be applied.

(Example) Examples are shown below, but these are representative of the present invention and do not limit the scope of the present invention. In addition, in the following examples, the melt flow of the thermoplastic polymer composition used for molding the molded article of the present invention was 0.5 to 25 g/1.
It was in the range of 0 minutes.

Examples 1 to 5 and Comparative Examples 1 to 3 A styrene-butadiene block copolymer having a polymer structure represented by the general formula -B-A was produced in cyclohexane using n-butyllithium as a catalyst. In the production of a block copolymer, M w / M n is adjusted by changing the ratio of the amount of styrene used in Part A and the amount of styrene used in Part II. The monomer mixture was adjusted by continuously feeding a monomer mixture of styrene and butadiene to the polymerization vessel and simultaneously changing the ratio. In addition, the melt flow index (Ml(G)) was adjusted by changing the amount of n-butyllithium.

The obtained block copolymer was pelletized using an extruder, and then melt-kneaded with polyphenylene ether and polystyrene using a twin-screw press ratio machine. After that, Toshiba Machine ■ IS-8OA
A printer cover was injection molded at 250°C using an injection molding machine.

A physical property measurement test piece was prepared from the obtained injection molded product, and the physical properties were measured. The results are shown in Table 1. Note that the molded product of Example 5 was warped.

The following margins (Note 1) (Note 2) (Note 3) (Note 4) (Note 5) (Note 6) (Note 7) Use polyphenylene ether resin with an intrinsic viscosity of 0.57/g (25°C chloroform) .

Uses Styron 685 manufactured by Asahi Kasei.

Conforms to ASTM D-1709 Conforms to JIS K-5400 Conforms to JIS L6714 Conforms to JIS K-6871 Condition of microcracks observed when bending and deforming a test piece based on the bending test method according to ASTM D-790 was observed, and the microcracking property was evaluated based on the amount of deformation in the center of the specimen at the time of microcracking.

◎： The amount of deformation when micro cracks occur is Exceeds 10mm.

The amount of deformation exceeds 3 peng and is less than 10 peng. Microcracks occur within this range.

Microcracks occur when the amount of deformation is 3 Mn or less 6 ○ ; A styrene-butadiene block copolymer was produced. A composition consisting of the obtained block copolymer and polyphenylene ether polystyrene was prepared and molded into a paper storage box for a copying machine by injection molding.

Physical property measurement test pieces were prepared from the obtained injection molded products, and the physical property measurement results are shown in Table 2. The molded product of the present invention had good impact resistance, pencil hardness, and heat resistance, and was free from warping and had excellent gloss.

Margin below (Note 8) Using a dumbbell test piece according to ASTM D638, the dead end portion was measured at an incident angle of 60° using a gloss meter manufactured by Suga Test Instruments.

Evaluation rank O: 95% or more △: 85% or more, less than 95%
B1-A2-B2-83 and (At-B+-)-1-X
A block copolymer represented by (X represents a residue of IJ a) was produced in the same manner as in Examples 1 to 5. The obtained block copolymer and polyphenylene °
A composition consisting of ether and polystyrene was prepared and molded into a cover for a paper storage box of a copying machine by injection molding.

Physical property measurement test pieces were prepared from the obtained injection molded products, and the physical property measurement results are shown in Table 3. No warping was observed in any of the molded products.

Example 15 100 parts by weight of the block copolymer composition of Example 1, 3 parts by weight of antimony trioxide, and 3 parts by weight of decabromotetralin.
After melt-kneading 0 parts by weight and 35 parts by weight of glass fiber to prepare pellets, a part of the chassis of a word processor was injection molded.

The obtained injection molded parts had excellent impact resistance, heat resistance, and scratch resistance, and exhibited good flame retardancy.

Example 16 A styrene-butadiene block copolymer having a polymer structure represented by general 2A, -B-A2 was produced in cyclohexane using n-butyllithium as a catalyst. after that,
This block copolymer was hydrogenated using a Ti-based hydrogenation catalyst described in JP-A-59133203 to produce a hydrogenated block copolymer in which about 99% of the aliphatic double bonds in the butadiene portion were hydrogenated.

Next, the obtained hydrogenated block copolymer was melt-kneaded with polyphenylene ether and polystyrene using a twin-screw extruder.

A receiver frame of a facsimile was injection molded from the obtained composition to obtain a molded product without warping. Table 4 shows the physical properties of the injection molded product.

Table 4 Example 17 A thermoplastic polymer composition similar to that used in Example 1 was used to injection mold a video cassette half.

A physical property measurement test piece was prepared from the obtained injection molded product, and the physical properties were measured and the results are shown in Table 5.

Example 18 A thermoplastic polymer composition similar to that used in Example 9 was used to injection mold an audio cassette half. A physical property measurement test piece was prepared from the obtained injection molded product, and the physical properties were measured and the results are shown in Table 5.

Table 5 (Note 9) No damage occurred even when the molded product was dropped naturally onto the floor from a height of 1 m.

Example 19 In the composition of Example 1, styrene/methyl methacrylate copolymer, impact-resistant rubber-modified styrene polymer (HIPS), acrylonitrile, etc. were used instead of polystyrene.
Butadiene-styrene copolymer (ABS), methyl methacrylate-butadiene-styrene copolymer (MBS)
Compositions were created using each of these. Injection molding a protective cover for a personal computer from the resulting composition;
A molded product with excellent impact resistance, surface hardness, and heat resistance was obtained.

〔Effect of the invention〕

Since the thermoplastic polymer composition used in the present invention has excellent transparency, impact resistance, surface hardness, heat resistance, and gloss, these characteristics can be utilized to form molded parts of information equipment, such as word processors and facsimiles. It can be suitably used as a molded body for equipment parts such as copying machines, printers, typewriters, office computers, and personal computers, and magnetic tape storage containers. In particular, the injection-molded article of the present invention has less warp, so it is suitable for flat molded articles, molded articles with many flat plate parts, and large-sized molded articles.

hand Continued Supplementary Positive book (spontaneous) October 1999 da Day

Claims (1)

[Scope of Claims] (a) Consisting of at least two polymer segments mainly composed of vinyl aromatic hydrocarbons and at least one polymer segment mainly composed of conjugated dienes, the vinyl aromatic hydrocarbon content is is more than 60% by weight and 95% by weight or less: 10 to 95 parts by weight (b) Polyphenylene ether 5 to 90 parts by weight (c) Vinyl aromatic hydrocarbon polymer The above component (a)
and component (b) 2 to 500 parts by weight based on the total amount of 100 parts by weight.