Preparation method for polycarbonate resin composition

Abstract

A preparation method for a polycarbonate resin composition that is characterized by involving a process for using, as a starting material, a polycarbonate resin that includes a polycarbonate-polyorganosiloxane copolymer (A), and for including at least one substance from among a styrene resin (B), a flame retardant (C), a flame retardant aid (D), and an inorganic filler (E). The polycarbonate-polyorganosiloxane copolymer (A) has a specific polycarbonate block (A-1) and a specific polyorganosiloxane block (A-2). The differential molecular weight distribution curve of the polyorganosiloxane block(A-2), which is obtained from measurement by gel permeation chromatography using polystyrene as a conversion standard and in which the horizontal axis is the logarithmic value log(M) of the molecularweight M and the vertical axis is the value dw / dlog(M) obtained by differentiating the concentration fraction w by the logarithmic value log(M) of the molecular weight, satisfies the following: (1) the maximum value of dw / dlog(M) is reached in the range of 3.4<=log(M)<=4.0; and (2) in the differential molecular weight distribution curve, the value obtained by integrating the values of dw / dlog(M)in the range of 4.00<=log(M)<=4.50 is 6-40% of the value obtained by integrating the values of dw / dlog(M) across the entire range of log(M).

Description

technical field [0001] The present invention relates to a method for producing a polycarbonate-based resin composition having impact resistance using a resin excellent in transparency as a raw material. Background technique [0002] Polycarbonate resin (hereinafter sometimes abbreviated as "PC resin") has attracted attention due to its excellent properties such as high impact resistance, chemical resistance, and flame retardancy. Therefore, it is expected to be widely used in various fields such as the field of electrical equipment, the field of electronic equipment, and the field of automobiles. In particular, applications to housings of mobile phones, mobile personal computers, digital cameras, video cameras, power tools, etc., and other daily necessities are expanding. [0003] Generally, 2,2-bis(4-hydroxyphenyl)propane [common name: bisphenol A is generally used as a representative polycarbonate resin. Sometimes abbreviated as "BPA"] Homopolycarbonate obtained from dih...

AI Technical Summary

Problems solved by technology

However, in this method, there is a problem that impact resistance decreases

[0006] In Patent Document 6, an attempt was made to improve transparency while maintaining excellent impact resistance by blending two types of polycarbonate-polyorganosiloxane copolymers having different light transmittances, but it cannot be said that the transparency is sufficient.

[0007] Thus, it has been difficult for conventional polycarbonate-based resin compositions to have both excellent transparency and excellent impact resistance, especially impact resistance at low temperatures.

[0008] Here, in a production line for producing polycarbonate-based resins, if a PC resin with low transparency is mixed with a PC resin with high transparency, the transparency of the finally obtained PC resin will be greatly reduced.

Therefore, in the case of producing PC resin with high transparency on the same production line after producing PC resin with low transparency, in order to suppress the decrease in transparency of the finally obtained PC resin, a long period of time is required when switching manufactured products. During the transition period, a significant decrease in productivity occurs

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