Document Type and Number:
Japanese Patent JPS5418313
Kind Code:
B1
Abstract:
Blends of tough, rubbery, essentially completely insoluble alkyl acrylate polymer and of a hard, unplasticized vinyl chloride resin in which a very small proportion of the rubbery polymer is uniformly dispersed as a more or less continuous network are superior high impact rigid resin formulations. Such a product is produced by a two-step overpolymerization process starting in the first step with small latex particles 200-1700 A, more preferably 250 - 1250 A, and most preferably 250 - 800 A, in average diameter of a vinyl chloride seed resin and overpolymerizing on such seed resin particles a thin layer 50 - 700 A, more preferably 100 - 500 A, and most preferably 125 to 350 A, in thickness of the rubbery polyacrylate and, in the second step overpolymerizing on the first step rubber-coated latex particles additional vinyl chloride resin to produce a rubber/resin concentrate or masterbatch which is unique in its ability to be diluted, preferably in powder form, with rubber-free vinyl chloride resin to obtain a final composition containing from about 3 to about 6, more preferably 3 to 5.5 parts/wt. of rubber network material for every 100 parts/wt. of total vinyl chloride resin. The latter blended granular composition requires fluxing and fusing under shear at 350 DEG - 440 DEG F., more preferably about 375 DEG to about 420 DEG F, to develop high resistance to impact (Izod values of 10 to 20 ft.lbs/in. or more), maximized resistance to distortion by heat, maximized resistance to chemicals, and heretofore unrealized high resistance to degradation during processing and during outdoor exposure. In addition, such compositions also are unique in requiring no resinous processing aids during processing on commercial equipment. The vinyl chloride seed resin may be crosslinked, preferably with a crosslinking agent that induces the formation of graft linkages between the seed and the rubbery phases. The blends also exhibit during processing excellent high viscosity hot strength, good high temperature body and dimensional integrity, low die swell, and a somewhat lower coefficient of expansion than many other high impact resin compositions.
Application Number:
JP4630172A
Publication Date:
July 06, 1979
Filing Date:
May 12, 1972
Export Citation:
International Classes:
C08F2/20; C08F259/04; C08L27/06; C08L51/00; (IPC1-7): C08F285/00; C08F2/16