Method for foaming a crystalline olefin polymer containing a blowing agent and a heat sink

Claim 1

A METHOD FOR FOAMING AN OLEFIN POLYMER HAVING A CRYSTALLINITY IN THE RANGE IF 5 TO 100 PERCENT INTO A UNIFORMLY CELLULAR MASS, SAID POLYOLEFIN HAVING A HEAT OF CRYSTALLIZATION SUFFICIENTLY HIGH TO PREVENT COMPLETE ABSORPTION OF THE RELEASED ENERGY DURING EXPANSION BY THE BLOWING AGENT ANY BY CONDUCTION OF THE THERMAL ENERGY RELEASED UPON SOLIDIFICATION AND HAVING BEEN PRODUCED BY POLYMERIXZING A 1-OLEFIN HAVING A MAXIMUM CHAIN LENGTH OF 8 CARBON ATOMS PER MOLECULE, WHICH COMPRISES UNIFORMLY DISPERSIN IN SAID POLYMER A NORMALLY GASEOUS BLOWING AGENT AND AN INERT HEAT SINK WHICH WILL EVAPORATE DURING THE COOLING OF SAID POLYMER AND WHICH HAS A SUFFICIENTLY HIGH LATENT HEAT OF VAPORIZATION TO BE ABLE TO ABSORB AT LEAST A PORTION OF THE THERMAL ENERGY RELEASED DURING THE SOLIDIFICATION OF THE POLYOLEFIN, SAID HEAT SINK BEING SELECTED FROM THE GROUP CONSISTING OF ALKANOLS HAVING FROM 3 TO 5 CARBON ATOMS PER MOLECULE, ELEVATING THE TEMPERATURE OF SAID DISPERSION TO MELT SAID POLYMER WHILE SUBJECTING SAID DISPERSION TO SUPERATMOSPHERIC PRESSURE SUFFICIENTLY HIGH TO PREVENT VAPORIZATION OF THE HEAT SINK, SUDDENLY RELEASING SAID PRESSURE TO PERMIT THE VAPORIZATION AND EXPENSION OF SAID NORMALLY GASEOUS BLOWING AGENT AND SAID HEAT SINK THEREBY EXPANDING, COOLING AND SOLIDIFYING SAID MOLTEN POLYMER TO FORM A MASS A LOW DENSITY FOAM, SAID HEAT SINK AND BLOWING AGENT BEING SELECTED SO AS TO OBSORB THE THERMAL ENERGY RELEASED DUE TO SENSIBLE HEAT AND HEAT IF CRYSTALLIZATION DURING THE PROCESS OF SOLIDIFYING THE POLYMER.

Claim 2

A METHOD FOR FOAMING AN OLEFIN POLYMER HAVING A CRYSTALLINITY IN THE RANGE IF 5 TO 100 PERCENT INTO A UNIFORMLY CELLULAR MASS, SAID POLYOLEFIN HAVING A HEAT OF CRYSTALLIZATION SUFFICIENTLY HIGH TO PREVENT COMPLETE ABSORPTION OF THE RELEASED ENERGY DURING EXPANSION BY THE BLOWING AGENT ANY BY CONDUCTION OF THE THERMAL ENERGY RELEASED UPON SOLIDIFICATION AND HAVING BEEN PRODUCED BY POLYMERIXZING A 1-OLEFIN HAVING A MAXIMUM CHAIN LENGTH OF 8 CARBON ATOMS PER MOLECULE, WHICH COMPRISES UNIFORMLY DISPERSIN IN SAID POLYMER A NORMALLY GASEOUS BLOWING AGENT AND AN INERT HEAT SINK WHICH WILL EVAPORATE DURING THE COOLING OF SAID POLYMER AND WHICH HAS A SUFFICIENTLY HIGH LATENT HEAT OF VAPORIZATION TO BE ABLE TO ABSORB AT LEAST A PORTION OF THE THERMAL ENERGY RELEASED DURING THE SOLIDIFICATION OF THE POLYOLEFIN, SAID HEAT SINK BEING SELECTED FROM THE GROUP CONSISTING OF ALKANOLS HAVING FROM 3 TO 5 CARBON ATOMS PER MOLECULE, ELEVATING THE TEMPERATURE OF SAID DISPERSION TO MELT SAID POLYMER WHILE SUBJECTING SAID DISPERSION TO SUPERATMOSPHERIC PRESSURE SUFFICIENTLY HIGH TO PREVENT VAPORIZATION OF THE HEAT SINK, SUDDENLY RELEASING SAID PRESSURE TO PERMIT THE VAPORIZATION AND EXPENSION OF SAID NORMALLY GASEOUS BLOWING AGENT AND SAID HEAT SINK THEREBY EXPANDING, COOLING AND SOLIDIFYING SAID MOLTEN POLYMER TO FORM A MASS A LOW DENSITY FOAM, SAID HEAT SINK AND BLOWING AGENT BEING SELECTED SO AS TO OBSORB THE THERMAL ENERGY RELEASED DUE TO SENSIBLE HEAT AND HEAT IF CRYSTALLIZATION DURING THE PROCESS OF SOLIDIFYING THE POLYMER.