KR840001493B1 - Thermoplastic resin composition having good heat cycle property - Google Patents

Abstract

A thermoplastic resin compsn., having good heat-cycle properties, consists of 100 wt.% of an ABS-type resin-poly-carbonate resin mixt. contg. 95 wt.% or less ABS-type resin, or 100 wt.% of polycarbonate resin and 0.05-3.0 wt.% organosilicone compd.

Description

Thermoplastic composition with excellent thermal cycling

The present invention relates to a thermoplastic resin composition having excellent thermal cycling properties. More specifically, the present invention relates to a thermoplastic resin composition having excellent heat cycle properties, molded articles thereof, and plated molded articles thereof. More specifically, based on the mixed weight of the polycarbonate resin and the ABS resin, the organo-silicon together with 100 parts by weight of the mixture containing ABS resin in an amount of less than 95% by weight or 100 parts by weight of the polycarbonate resin The present invention relates to a thermoplastic resin composition having excellent thermal cycling properties containing 0.05 to 3.0 parts by weight of a compound. Undesirable "swelling" occurs frequently in metal-plated plastic products between the plastic substrate surface and the metal film plated thereon. This is because the difference in the coefficient of linear expansion between the plastic gas and the metal film is large and separated from each other due to changes in environmental conditions, especially temperature. The properties of plastics, plastic products or plated plastic products involved in this swelling are referred to as "thermal cycling".

In recent years, the demand for plated plastic products, which are cheap and lightweight, is rapidly increasing. In addition, plated plastic products tend to be used under strict conditions. Therefore, there has been a great demand for the appearance of plated plastic products having good thermal cycling. Until now, polycarbonate resins have been widely used as thermoplastic resins suitable for metal plating. However, its thermal cycle is not high enough. In order to improve the thermal cycle, a method of plating a metal film thickly, for example, 40 to 50 µ in copper, 10 to 20 µ in nickel, and 0.1 to 0.3 µ in chromium, has been proposed. It must be.

These effects are also insufficient. In addition, copper plating has been considered indispensable for reducing the effects of the difference in the coefficient of linear expansion between the plastic substrate and the metal film, but there has been a problem of corrosion. In the case of omitting copper plating, so-called "double nickel plating" or "triple nickel plating" has been proposed, but the product thus manufactured has much lower thermal cycling. As a result of extensive research, a thermoplastic resin composition comprising a polycarbonate resin or a mixture of ABS resin and an organo-silicon compound is provided as a molded product for metal plating, and the plated product is heat cycleable. It turns out that this is excellent. It should be noted that the molded product of the thermoplastic resin composition is obtained as a plated product having satisfactory thermal cycle even when the plated metal film is thin and the metal plating is made of nickel plating without copper plating.

The thermoplastic composition of the present invention is organic-based with 100 parts by weight of polycarbonate resin or 100 parts by weight of a mixture containing ABS resin in an amount of less than 95% by weight based on the mixed weight of polycarbonate resin and ABS resin. The silicon compound is composed of 0.05 to 3.0 parts by weight. The polycarbonate resin may be any known one, but is usually prepared by polymerizing 2,2- (4,4′-dihydroxydiphenyl) -propane as a diol component by a transesterification method or a phosgene method. Aromatic polycarbonates, such as polycarbonates of 4′-dihydroxydiphenylalkane, are used (a typical example of polycarbonate resins and their preparation is described in Polymer Science and Technology, Described on page 764 (1969). ABS resins are graft copolymers prepared by graft polymerization of two or more monomers selected from the group consisting of aromatic vinyl compounds, vinyl cyanide compounds and diene rubber with methacrylic acid esters: aromatic vinyl compounds, vinyl cyanide compounds and methacryl A mixture of a copolymer obtained by polymerization of at least two monomers selected from the group consisting of acid esters and the graft copolymers described above: of monomers selected from the group consisting of aromatic vinyl compounds, vinyl cyanide compounds and methacrylic acid esters, and the like. It is selected from the mixture of the copolymer obtained by the at least 2 types of superposition | polymerization, the copolymer manufactured from the vinyl cyanide compound, and the diene monomer. Examples of the diene rubbers include poly-butadiene, acrylonitrile-butadiene copolymers, styrenebutadiene copolymers, and the like. Examples of the aromatic vinyl compound include styrene α-methylstyrene, methyl-α-methylstyrene, vinyltoluene alkoxystyrene, vinylpyridine, and the like. Examples of the vinyl cyanide compound include acrylonitrile, methacrylonitrile, chloroacrylonitrile and the like.

Examples of methacrylates include methyl methacrylate, ethyl methacrylate, and the like. The graft polymerization and the polymerization reaction described above may be carried out by ordinary polymerization methods such as emulsion polymerization, suspension polymerization, solution polymerization, bulk polymerization or emulsion-suspension polymerization. (A typical example of ABS resin and its preparation is polymer science and technology. Dictionary 1, 436-444 (1964) and Kirk-Othmer's Encyclopedia of Chemical Technology, 3rd Edition, Volume 1, 442-456 (1978). In the case of using an ABS resin, the amount is less than 95% by weight, preferably 10 to 80% by weight based on the mixed weight of the polycarbonate and the ABS resin.

If the amount of ABS resin is 95% by weight or more, sufficient heat resistance cannot be obtained, and the plated molded product made of the obtained thermoplastic resin composition is easily deformed, and when used at an elevated temperature, cracking occurs in the metal film plated on the molded product. Let's do it.

As organo-silicon compounds, R ¹ to R ⁴ are lower alkyl or aryl, and m is 1 to 2,000.

Polysiloxanes: R ¹ to R ⁴ are the same as defined above, respectively; Silane of R ¹ R ² R ³ R ⁴ Si; R is lower alkyl or aryl, X is halogen and n is an integer of 1 to 3; Halosilanes of R ₄ -nSiX _n and the like can be used. More specifically, polysiloxanes (ie, polydimethylsiloxane, polymethylethylsiloxane, polydiethylsiloxane, polymethylphenylsiloxane), silanes (ie, tetraethylsilane, trimethylhexane), halosilanes (ie, triethylchlorosilane, Diethyl dicyclosilane, phenyltrichlorosilane, diphenyldichlorosilane) and the like can be used. These organo-silicon compounds preferably have a viscosity of 10 ¹ to 10 ⁵ cst (centistokes) for convenience in mixing.

The organo-silicon compound is used in an amount of 0.5 to 3.0 parts by weight based on 100 parts by weight of the polycarbonate resin containing the ABS resin type resin when using the ABS type resin. When less than this amount, the uniform dispersion cannot be obtained and thermal cycling property will fall. When the amount is higher than this amount, the operation during addition and kneading becomes somewhat difficult, and thermal cycle and heat resistance are lowered.

To prepare the thermoplastic resin composition of the present invention, a polycarbonate resin, an organo-silicon compound or a polycarbonate resin ABS type resin, and an organo-silicon compound are usually mixed together by a mixing operation. If necessary, preliminary additives such as stabilizers, lubricants or fillers may be added thereto.

The thermoplastic resin composition thus prepared is then molded into the shape required by the usual molding method such as injection molding or extrusion molding. Following the molded article prepared in this way, a typical embodiment of the metal plating by the plating method is shown in the following table.

Figure 1.

In the typical plating operation described above, a copper film and then a nickel film are formed on the molded article surface. In order to improve corrosion resistance, the second copper sulfate bath is often replaced by one nickel sulfate bath or two nickel sulfate baths. In this case, two kinds of nickel plating or three kinds of nickel plating are performed. Usually, these two nickel-plated or three-nickel-plated products have a significant decrease in thermal cycling. However, when the resin composition of the present invention is used as a base material, excellent thermal cycleability can be achieved even in double nickel plating or triple nickel plating products.

Practical, practical and preferred embodiments of the present invention are well illustrated by the following examples in which parts and percentages are by weight unless otherwise indicated.

Thermal cycling was tested by the following method:

After plating, the molded product was allowed to stand at room temperature for 15 minutes and then left for 1 hour in a -40 ° C cooler. The molded product was taken out of the cooler, left for 15 minutes at room temperature, and then left at 110 ° C for 1 hour. The molded product was then placed in a stove and left for 15 minutes at room temperature.

These cycles are repeated by taking one of the above processes (ie room temperature / 15 minutes → -40 ° C./1 hour → room temperature / 15 minutes → + 110 ° C./1 hour) in one cycle. At the end of each cycle, if no abnormalities such as swelling or cracking appear on the plated film of the molded product, it is determined that the thermal cycle test has been passed. The thermal cycleability of the resin composition is expressed as the number of passed samples / number of test samples after the end of a specific cycle.

[Example 1-5 and Comparative Example 1-4]

A resin composition was prepared by mixing polycarbonate resin, ABS resin and organo-silicon compound together at a ratio shown in Table 1 with a Banbury mixer at a temperature of 200 to 220 ° C. for 5 minutes. This resin composition was injection molded using an injection molding machine (50z) to produce ten jar openings.

The openings were prepared in Examples 1 and 3 to 5 and Comparative Examples 1, 3 and 4 by copper (thickness 20μ), nickel (thickness 10μ) and chromium (thickness 0.2μ) by the method shown in Table 1 or by the method of remodeling thereof. Example 2 In Comparative Example 2, nickel (matte; thickness 14μ), nickel (gloss; thickness 6μ) and chromium (thickness 0.1μ) were plated. Thermal cycling is measured and the results are shown in Table 1.

TABLE 1

Claims (1)

100 parts by weight of the mixture containing ABS resin in an amount less than 95% by weight based on the weight of the mixture of the polycarbonate resin and the ABS resin or 100 parts by weight of the polycarbonate resin and 0.05 to 3.0 parts by weight of the organic-silicon compound A thermoplastic resin composition having excellent heat cycle properties composed of parts.