Method of making polyethylene foam
Abstract
Abstract A PROCESS FOR PREPARING POLYETHYLENE FOAM CONSISTING ESSENTIALLY OF FORMING A MIXTURE OF SOLID POLYETHYLENE AND NORMALLY SOLID, HEAT DECOMPOSABLE ORGANIC FOAMING AGENT HAVING A DECOMPOSITION TEMPERATURE AT LEAST ABOUT 10*C. ABOVE THE MELTING POINT OF THE POLYETHYLENE MATERIAL; SUBJECTING SAID ADMIXTURE TO HIGH ENERGY IONIZING RADIATION TO PRODUCE A PERCENT GEL OF ABOUT 30 TO ABOUT 80; HEATING THE IRRADIATED BODY IN STAGES, FIRST AT A TEMPERATURE SLIGHTLY BELOW THE DECOMPOSITION POINT OF THE FOAMING AGENT AND IMMEDIATELY THEREAFTER RAPIDLY HEATING TO A TEMPERATURE WELL ABOVE THE DECOMPOSITION POINT TO FORM AN EXPANDED BODY AND COOLING THE HEATED BODY TO A TEMPERATURE BELOW THE FREEZING POINT OF THE POLYETHYLENE.
Inventors
- 👤 William A Patterson
- 👤 Stanley Norman Weissman
- 👤 Henry G Schirmer
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
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