Patent ID: 6143212
Filing Date: 2000-11-07
Classification: B01J,B29B

Abstract:
A super-low temperature plastic powder manufacturing method using gas, comprising the following steps:(a) material melting, wherein coarse granular thermo-plastic material is melted to form a plastic solution;(b) high air pressure blowing for separation, wherein high pressure air is injected to impact said plastic solution to cool and harden it gradually and to thereby reduce its adhesive strength, said plastic solution is subjected to said high pressure air blowing to gradually form fine, rounded plastic micro-granules;(c) super-low temperature liquid nitrogen impacting for brittling, wherein super low temperature liquid nitrogen is used to impact said plastic micro-granules, thereby greatly reducing elongation, impact strength, and fracture resistance of said plastic micro-granules, therefore, said plastic micro-granules are rendered brittle and extremely fragile; and(d) low temperature calendaring, wherein said fine, rounded plastic micro-granules are subjected to pressing rolling by a pair of low temperature rolling wheels, said low temperature calendaring is also under the action of said super low temperature liquid nitrogen.