| 摘要 |
PURPOSE:To prepare a vinyl chloride resin composition improved in heat resistance by previously dissolving an antioxidant in a plasticizer and adding the solution to a vinyl chloride resin. CONSTITUTION:As the vinyl chloride resin used, one produced by a suspension polymerization process or a bulk polymerization process and having an average degree of polymerization of 700-10000 is desirable. The antioxidant is used in an amount of 0.1-5 pts.wt. per 100 pts.wt. resin and is used in the form of a solution prepared by previously dissolving in a plasticizer. It is preferable that the antioxidant used is a phenolic antioxidant, a sulfur antioxidant or a phosphorus antioxidant and has a molecular weight of 500 or above and a melting point of 40 deg.C or above. The dissolution of the antioxidant in the plasticizer is carried out with slow agitation at 200 deg.C or below. Although the plasticizer is not particularly limited, it is suitably has a molecular weight of 400 or above. When oil resistance in addition to heat resistance is necessary, a polyester plasticizer is used. When heat resistance, thermal aging resistance and oil resistance are further to be improved, an alkyl biphenyltetracarboxylate is suitably used. The amount of the plasticizer used is 10-200 pts.wt. per 100 pts.wt. resin. |
