METHOD FOR RAPID PURGING OF BLOWING AGENTS FROM FOAMED POLYMER PRODUCTS

摘要

Objects of thermoplastic polymer foam such as, e.g., sheeting of polyolefins such as polyethylene, are treated at elevated temperatures effective to rapidly purge the foam of a substantial portion of the residual blowing agent. Significant economies are achieved by reducing the amounts of residual blowing agents (such as flammable, toxic or environmentally hazardous gases) to levels presenting no fire hazard or other safety hazards in times substantially less than required in conventional aging under ambient conditions. The processes can be carried out in ovens or other heating zones which form continuations of the basic production line, with the extracted blowing agents recycled or disposed of by combustion.