JPS6223784B2 - - Google Patents

Description

[Detailed description of the invention]

[] Background of the Invention The present invention relates to a modified aromatic polycarbonate resin composition that is improved in moldability, mechanical properties, and the like. More specifically, the present invention relates to a composition having as one component a modified polycarbonate resin obtained by polymerizing a vinyl or vinylidene monomer on an aromatic polycarbonate resin. Aromatic polycarbonate resin has the highest level of impact resistance among thermoplastic resins, as well as good electrical properties, heat resistance, and transparency, so it is used mainly in the electrical and electronic equipment fields as a so-called engineering plastic molding material. It is widely used. However, this resin has poor flowability during molding, resulting in inferior moldability for complex-shaped products or large parts, and has a long shot cycle during injection molding, making it difficult to manufacture compared to other easily moldable materials. Currently, they have problems in terms of molding processing, such as poor properties, and cannot be used as easily as general-purpose resins. Furthermore, since the molding temperature tends to be high in order to avoid the problem of poor fluidity during molding, the molded product tends to yellow, which tends to cause problems in terms of product quality. From this point of view, improving the fluidity of aromatic polycarbonate resin while maintaining its quality characteristics has become a major goal for expanding the market for this resin, and various studies have been carried out to date. ing. For example, aromatic polycarbonate resins are blended with vinyl resins such as polystyrene, ABS resins, or olefin resins such as polyethylene. However, aromatic polycarbonate resins and polyethylene have poor compatibility and have significantly different refractive indexes, so the blended product becomes opaque and its practical use is extremely limited. Even in the case of aromatic polycarbonate resin and ABS resin, although the compatibility between them is relatively good, the transparency of the blended product is still impaired. On the other hand, although aromatic polycarbonate resin and polystyrene give relatively transparent compositions, the dependence of the melt viscosity of the two components on shear rate is significantly different, so phase separation of the two components occurs during injection molding at high shear rates. Recognized,
Its practicality was low. In order to improve these drawbacks, aromatic polycarbonate resin is dissolved in a vinyl or vinylidene monomer or a mixture of this monomer and a solvent, and a polymerization initiator for this monomer is added to form a bulk polymerization method. Alternatively, a method is known in which this monomer is grafted onto an aromatic polycarbonate resin by a bulk-suspension polymerization method. However, with this method, the polymerization system becomes highly viscous, making it difficult to stir and remove the heat of polymerization.To avoid this, adding a large amount of solvent to reduce the viscosity increases production costs due to solvent recovery. cormorant. In order to solve this problem, the present inventor has made a proposal (Japanese Patent Application No. 106059/1982). That is, the method consists of impregnating aromatic polycarbonate resin particles dispersed in an aqueous medium with a vinyl or vinylidene monomer and polymerizing the monomer in the state of this aqueous dispersion.
The modified polycarbonate resin obtained in this way has been improved with respect to the above-mentioned problems,
It can be used in a wide range of applications as a molding material with improved flowability. [] Summary of the Invention (Summary) The present invention specifies this prior invention more specifically, and relates to a specific resin composition containing this modified polycarbonate resin. Therefore, the modified polycarbonate resin composition according to the present invention is characterized by mainly consisting of the following components. Ingredients: 100 parts by weight of a modified aromatic polycarbonate resin prepared by the method below.Production method: Aromatic polycarbonate resin particles are impregnated with vinyl or vinylidene monomer in an aqueous medium so that the amount of the free monomer is 50% by weight. Then, the temperature of this aqueous dispersion is raised to polymerize the monomer. Ingredients Thermoplastic resin selected from the following group: 5 to 250 parts by weight (1) Aromatic polycarbonate resin, (2) Styrenic thermoplastic resin, (3) Acrylic or methacrylic thermoplastic resin, (4) Vinyl chloride resin resins, (5) mixtures of two or more of these resins. (Effects) In addition to the properties inherent to the modified polycarbonate resin according to the prior invention, the composition of the present invention has properties resulting from the combined use of the components according to the present invention. Therefore, products containing the above-mentioned specific resin materials as components have high impact resistance,
It has excellent dimensional stability, heat resistance, surface hardness, toughness, etc. Furthermore, those containing inorganic fillers have excellent mechanical strength, heat resistance, creep resistance, and dimensional stability. [] DETAILED DESCRIPTION OF THE INVENTION The composition of the present invention mainly consists of components. 1 component An aromatic polycarbonate resin modified with vinyl or vinylidene monomer. (1) Aromatic polycarbonate resin particles The aromatic polycarbonate resin used is
At least most of the dihydroxy compounds constituting the carbonic acid ester have two phenolic hydroxyl groups. Specifically, there are bisphenols, especially bisphenol A. Aromatic polycarbonate resins may be produced by reacting the above-mentioned "dihydric phenols" with carbonate precursors, such as phosgene, bischloroformates, carbonic diesters, etc., but in the present invention, suitable products are available on the market. Bye. The aromatic polycarbonate resin used in the present invention is in the form of particles. The particle size is preferably 1 to 5 mm. Particle sizes smaller than the above can be used if the particle properties can be sufficiently maintained in an aqueous medium after impregnation with vinyl or vinylidene monomers, while larger particles can also be used if a crushing operation is not required after polymerization. It is. (2) Vinyl or vinylidene monomer Any radical polymerization is possible as long as the required amount can be impregnated into a given aromatic polycarbonate resin particle in an aqueous medium and the desired modification effect can be produced in the polycarbonate resin. Vinyl or vinylidene monomers can be used. Specific examples of vinyl or vinylidene monomers that can be used in the present invention include styrene and styrene derivatives, such as α-methylstyrene, vinyltoluene, chlorostyrene, methacrylic esters such as methyl methacrylate (especially C ₁ - C ₈ alkyl esters), acrylic esters such as ethyl acrylate, etc.
_C1 - _C8 alkyl esters), conjugated dienes such as 1,3-butadiene and isoprene, vinyl esters such as vinyl acetate, unsaturated nitriles such as acrylonitrile and methacrylonitrile, vinyl chloride, vinylidene chloride, etc. There are unsaturated monos or dihalides, etc. These can be used together. In addition, such monomers may include crosslinkable diene or polyene monomers,
For example, a very small amount of divinylbenzene can be used in combination. The amount of vinyl or vinylidene monomer is 1 part by weight per 100 parts by weight of the aromatic polycarbonate resin.
It is preferably about 50 parts by weight, particularly about 3 to 40 parts by weight. If it is less than 1 part by weight, the effect of improving moldability is not sufficient, while if it is more than 50 parts by weight, not only can no further improvement in moldability be expected, but the impact resistance and heat resistance, which are characteristics of aromatic polycarbonate resin, are descend. Furthermore, during impregnation or polymerization, the aromatic polycarbonate is dissolved in these vinyl or vinylidene monomers, and the resulting improved particles may have irregular particle sizes or become blocked, making stirring impossible. (3) Radical polymerization initiator In the present invention, aromatic polycarbonate resin particles are impregnated with vinyl or vinylidene monomer in an aqueous medium without substantially polymerizing the monomer, and then this aqueous dispersion is heated. Monomers are polymerized, and the polymerization is usually promoted by a radical polymerization initiator. Moreover, this polymerization initiator must be able to be impregnated into the aromatic polycarbonate resin particles together with the monomer. Therefore, the radical polymerization initiator used in the present invention is oil-soluble. Preferably, the decomposition temperature is 50 to 150°C to obtain a half-life of 10 hours. Here, "decomposition temperature to obtain a half-life of 10 hours" means that when 0.1 mole of polymerization initiator is added to 1 liter of benzene and left at a certain temperature for 10 hours, the decomposition rate of the polymerization initiator is It means that temperature which is 50%. It goes without saying that if the impregnation step is carried out at a sufficiently low temperature, a polymerization initiator that is more decomposable at lower temperatures can be used. Specific examples of radical polymerization initiators that can be used in the present invention include lauroyl peroxide (62°C), benzoyl peroxide (74°C), t
- Organic peroxides such as butyl peroxybenzoate (104 °C), dicumyl peroxide (117 °C), etc., azobisisobutyronitrile (65 °C), etc.
℃), and others (the temperature in the above-mentioned cutlet is the above-mentioned half-life temperature). There is no limit to the amount of polymerization initiator, but it is generally about 0.01 to 10% by weight of the monomer weight used, usually
It is about 0.1 to 2.0% by weight. The polymerization initiator is usually used dissolved in vinyl or vinylidene monomer. (4) Impregnation of polycarbonate resin particles with a monomer in an aqueous medium A typical method for impregnating aromatic polycarbonate resin particles with a vinyl or vinylidene monomer in an aqueous medium is to impregnate an aqueous dispersion of polycarbonate resin particles with a monomer. Preferably, the monomer in which a polymerization initiator (and other additives as necessary) is dissolved is added and stirred. Another method is to add polycarbonate resin particles to an aqueous dispersion of monomers dissolved in a polymerization initiator and stir the mixture. The impregnation step should be operated at a sufficiently low temperature in relation to the decomposition temperature of the polymerization initiator used, generally between room temperature and 100 DEG C., so that substantially no polymerization occurs. In this step, the monomer is impregnated such that the amount of free monomer is 50% by weight or less of the amount of monomer used. Aromatic polycarbonate is relatively compatible with vinyl monomers and vinylidene monomers, so even if 50% by weight or more of the monomers are liberated before the start of polymerization, these monomers will become aromatic during polymerization. Since the polycarbonate particles are impregnated (including attached), the polymer particles obtained by polymerizing these monomers will not precipitate independently from the modified aromatic polycarbonate resin particles. The impregnation time is usually about 5 minutes to 3 hours. The content of aromatic polycarbonate resin particles and vinyl or vinylidene monomer in the aqueous dispersion is usually about 30 to 70% by weight. Such aqueous dispersions can be maintained in a stable dispersed state simply by sufficient stirring, but dispersions can be prepared more easily and stably by using an appropriate suspension stabilizer. can. As the suspension stabilizer in this case, those that can be used as a suspension stabilizer in the aqueous suspension polymerization of vinyl or vinylidene monomers can generally be used, and specifically, for example, polyvinyl alcohol, Water-soluble polymer substances such as methylulose and hydroxycellulose, anionic surfactants such as alkylbenzene sulfonates, non-ionic surfactants such as polyoxyethylene alkyl ether, and water-insoluble polymers such as magnesium oxide and calcium phosphate. Inorganic salts, etc., alone or in combination, are 0.01 to 0.01 to water.
It is used in an amount of about 10% by weight. When impregnating aromatic polycarbonate resin particles with vinyl or vinylidene monomers (and polymerization initiators), auxiliary materials such as plasticizers, lubricants, ultraviolet stabilizers, antioxidants, foaming agents, mold release agents, and colorants are used. (these auxiliary materials may already be added to the polycarbonate resin). (5) Polymerization If the aqueous dispersion thus prepared is heated to a temperature above which the polymerization initiator used decomposes at an appropriate rate, the impregnated vinyl or vinylidene monomer will polymerize. As a result, modified aromatic polycarbonate resin particles are produced. Since radical polymerization is to be carried out, heating should be carried out in an atmosphere substantially free of oxygen, and it is preferable to appropriately stir the aqueous dispersion during polymerization. The polymerization temperature is determined in correlation with the decomposition temperature of the polymerization initiator used, and is generally about 50 to 150°C, and the polymerization temperature does not need to be constant throughout the polymerization period. The polymerization time is usually about 2 to 10 hours. Polymerization pressure is normal pressure ~ 10Kg/cm ²
The degree is normal. After polymerization, if the same post-treatment as for normal aqueous suspension polymerization of styrene is performed, the shape of the aromatic polycarbonate resin particles used is maintained almost unchanged, and the modified aromatic polycarbonate resin particles can be used immediately as a molding material. Aromatic polycarbonate resin particles are obtained. The modified aromatic polycarbonate of the present invention is an aromatic polycarbonate containing a homogeneously dispersed polymer of vinyl or vinylidene monomers, or a vinyl or vinylidene monomer grafted onto an aromatic polycarbonate backbone, or It is presumed to be a mixture, and the polymer particles unique to the vinyl monomer do not exist separately from the aromatic polycarbonate particles. 2 Component The component is a specific thermoplastic resin. These are usually amorphous. (1) Aromatic polycarbonate resin An appropriate one may be selected from the aromatic polycarbonate resins described above to be modified with vinyl or vinylidene monomers. (2) Styrenic thermoplastic resin A typical example is a homopolymer of styrene or a styrene derived by substitution in the nucleus or side chain (particularly methyl or halo (particularly chloro) substituted products). Other typical examples are such copolymers of styrene or substituted styrene, especially in two-component systems in which styrene or substituted styrene accounts for at least 50% by weight of the monomer components. Specifically, for example, styrene-acrylonitrile, acrylonitrile-(poly)butadiene-
Copolymers (including graft copolymers) of styrene, acrylonitrile-chlorinated polyethylene-styrene, acrylonitrile-ethylenepropylene rubber-styrene, methyl methacrylate-(poly)butadiene-styrene, styrene-elastomer-methyl methacrylate, etc. There is. (3) Acrylic or methacrylic thermoplastic resin One representative example is a thermoplastic homopolymer of acrylic acid or methacrylic acid, or its functional derivatives such as salts, amides, and esters.
Typical monomers are esters, especially lower alkyl esters. Other representative examples are such copolymers of acrylic monomers, especially those in which acrylic monomers account for at least 50% by weight of the monomer component. Specific examples include methyl acrylate-acrylonitrile copolymer, ethyl acrylate-styrene copolymer, and ethyl acrylate-ethyl methacrylate copolymer. (4) Vinyl chloride resin There are homopolymers and copolymers of vinyl chloride or vinylidene chloride. Comonomers for the copolymer include, for example, vinyl acetate, ethylene, acrylic acid or its ester, and others. (5) Mixtures of these It goes without saying that a mixture of at least two of the above four resins is intended, but a small to non-essential amount of compatible thermoplastic resins other than those listed above may also be added. It is also within the scope of the present invention. It should be noted that even when these four resins are used alone, cases where a small amount or a non-essential amount of compatible thermoplastic resins other than these are included are also within the scope of the present invention. 3. Inorganic filler and others By incorporating an inorganic filler into the resin composition of the present invention, additional effects such as a reinforcing effect and a dimensional stabilizing effect can be imparted. Inorganic fillers include calcium carbonate, soft clay, talc, mica, silica powder, glass powder,
Basic magnesium carbonate, magnesium hydroxide,
Non-reinforcing powder fillers such as calcium sulfate, inorganic pigments such as titanium oxide and zinc oxide, metal powders such as aluminum, copper and iron, carbon black,
There are reinforcing powder fillers such as finely divided silicic acid, synthetic silicates, and hard clay, fibrous inorganic fillers such as glass fiber, asbestos, rock wool, and slag wool, and other inorganic fillers that can be blended into modified polycarbonate resins and thermoplastic resins. All fillers can be used for the purposes of this invention. These can be used alone or in combination. The resin composition of the present invention can contain various other auxiliary materials that can be contained in the thermoplastic resin composition.
Specifically, there are, for example, antioxidants, ultraviolet absorbers, pigments or dyes other than those mentioned above, neutralizing agents, antistatic agents, foaming agents, lubricants, mold release agents, and others. 4. Mixing ratio The mixing ratio of the components is as follows. Component: 100 parts by weight Component: 5 to 250 parts by weight, preferably 20 to 200 parts by weight The inorganic filler added as necessary is 5 to 230 parts by weight, preferably 10 to 200 parts by weight, per 100 parts by weight of the total amount of components. , is. Other auxiliary materials may be used in conventional amounts. 5. Compounding method and others Ingredients, inorganic fillers, etc. to be blended as necessary are prepared using ordinary resin melt-kneading methods, such as single-screw extruder, twin-screw extruder, roll, Banbury, etc., to ensure that each component is homogeneous. It can be melted and kneaded into pellets. Furthermore, by dry blending, it is also possible to directly mold the pellets obtained by simply mixing the pellets of each component. In addition to the method of kneading or dry blending the inorganic filler to the above resin composition, it is also possible to knead or dry blend resin pellets with a high content of inorganic filler (masterbatch) to the above resin composition. be. 6 Experimental Examples Example 1 Into an autoclave with a capacity of 80, 36 kg of pure water, 720 g of tricalcium phosphate as a suspending agent, and 1.8 g of sodium dodecylbenzenesulfonate as a suspending agent were added to create an aqueous medium, and this was used as an aqueous medium. aromatic polycarbonate resin particles (Teijin Kasei product "Teijin Panlite L1250" average particle size of approximately 3
mm) 12.6Kg was suspended by stirring. Separately, t-butyl peroxybenzoate 10 is used as a polymerization initiator.
g in 5.4 kg of styrene and put it into the suspension system, and after replacing the inside of the autoclave with nitrogen gas, the temperature inside the system was raised to 90°C and held at this temperature for 3 hours to start polymerization. Styrene containing the agent was impregnated into polycarbonate resin particles. This aqueous suspension was heated to 100°C, and at that temperature
Polymerization was carried out by maintaining the temperature for a certain period of time, and the temperature was further raised to 130°C, and the temperature was maintained for 3 hours to complete the polymerization.
After cooling, the contents were taken out and washed with acid and water to obtain 18 kg of styrene-modified polycarbonate particles (polystyrene content: 30% by weight). Furthermore, styrene-modified polycarbonate particles having a styrene content of 3% by weight and 10% by weight were obtained in the same manner by changing the amount of styrene. 100 parts by weight of the modified polycarbonate thus obtained (polystyrene content 30 and 10% by weight) and 200 parts by weight of unmodified polycarbonate (Teijin Panlite L1250) were blended, Fluidity due to spiral flow was measured at a molding temperature of 280°C under the conditions of an injection pressure of 1000 kg/cm ² , an injection time of 15 seconds, a cooling time of 20 seconds, and a mold temperature of 40°C using a Uinlite method (injection capacity: 5 ounces). As a result, this blend retains the same finely dispersed polystyrene structure as the modified polycarbonate (styrene content 10% by weight), and its fluidity is similar to that of the modified polycarbonate with the same polystyrene content. have. Furthermore, even in the region where the modified polycarbonate is diluted with the unmodified polycarbonate and contains very little polystyrene, the fluidity is significantly improved compared to the unmodified polycarbonate, and the transparency does not decrease at all. The results are shown in Table-1-1. Comparative Example 1 Aromatic polycarbonate used in Example-1 (Teijin Kasei product “Teijin Panlite L1250”)
and polystyrene ("Dialex HF77" manufactured by Mitsubishi Monsanto) were blended, and the fluidity by spiral flow was determined under the same conditions as in Example 1. The results are shown in Table-1-2. When compared with all compositions with the same polystyrene content, in the case of a simple blend, the flowability improvement effect is small and the degree of haze is also reduced.

【table】

[Table] Example 2 A predetermined amount of unmodified polycarbonate and glass fiber as an inorganic filler were combined with the modified polycarbonate obtained in Example 1 (polystyrene content of 30 and 10% by weight), and an injection molding machine (manufactured by Meiki Manufacturing Co., Ltd.) was used. Screw line type (injection capacity 5 oz), injection pressure 1000Kg/cm ² , injection time 15 seconds, cooling time 20 seconds,
The fluidity due to spiral flow was measured at a molding temperature of 280°C under the conditions of a mold temperature of 40°C, and the results are shown in Table 2. Comparative Example 2 A predetermined amount of glass fiber as an inorganic filler was combined with the unmodified polycarbonate used in Example 1, and the fluidity by spiral flow was measured under exactly the same conditions as in Example 2. The results are shown in Table-2. In the case of unmodified polycarbonate, when glass fibers are introduced, the moldability deteriorates significantly, and injection molding becomes difficult at high filling amounts. However, when compared to Example 2 with the same glass fiber loading, it is clear that the presence of the modified polycarbonate significantly improved the fluidity. When compared with the same filling amount, approximately 1.2 times more fluidity can be imparted.

[Table] Example 3 The modified polycarbonate obtained in Example 1 (polystyrene content 30%) was combined with predetermined amounts of calcium carbonate and talc as inorganic fillers, and unmodified polycarbonate (Teijin Panlite L1250), Fluidity due to spiral flow was measured under the same conditions as in Example 2 at a molding temperature of 280°C. The results are shown in Table-3. Comparative Example 3 A predetermined amount of calcium carbonate and talc as inorganic fillers were combined with the unmodified polycarbonate used in Example 1, and the fluidity by spiral flow was measured under exactly the same conditions as in Example 3. The results are shown in Table-3. Introducing calcium carbonate and talc into unmodified polycarbonate significantly deteriorates flowability, making injection molding difficult at high loadings. However, the presence of modified polycarbonate as in Example 3 significantly improves flowability.

[Table] Example 4 The modified polycarbonate obtained in Example 1 (polystyrene content 10%) was added with polystyrene ("Dialex HF77" manufactured by Mitsubishi Sunmont Corporation) as an amorphous thermoplastic resin, and an acrylonitrile-styrene copolymer ( AS resin) (Daicel “Sevian No.
10''), further combined with a predetermined amount of unmodified polycarbonate (Teijin Panlite L1250), Example 2
The fluidity due to spiral flow was measured under the same conditions as above at a molding temperature of 280°C. This result is shown in Table-
As shown in 4. Comparative Example 4 To the unmodified polycarbonate resin used in Example 1, specified amounts of polystyrene (Mitsubishi Monsanto "Dialex HF77") and acrylonitrile-styrene resin (Daicel "Sevian No. 10") were added as amorphous thermoplastic resins. The fluidity by spiral flow was measured under the same conditions as in Example 4. The results are shown in Table-4. Compared to Example 4, the effect of improving fluidity by adding the modified polycarbonate is remarkable.

【table】

Claims (1)

[Scope of Claims] 1. A modified polycarbonate resin composition mainly consisting of the following components. Ingredients: 100 parts by weight of a modified aromatic polycarbonate resin prepared by the method below.Production method: Aromatic polycarbonate resin particles are impregnated with vinyl or vinylidene monomer in an aqueous medium so that the amount of the free monomer is 50% by weight. Then, the temperature of this aqueous dispersion is raised to polymerize the monomer. Ingredients Thermoplastic resin selected from the following group: 5 to 250 parts by weight (1) Aromatic polycarbonate resin, (2) Styrenic thermoplastic resin, (3) Acrylic or methacrylic thermoplastic resin, (4) Vinyl chloride resin resins, (5) mixtures of two or more of these resins. 2. The modified polycarbonate resin composition according to claim 1, which contains 5 to 230 parts by weight of an inorganic filler per 100 parts by weight of the total amount of components.