摘要 |
Process for the preparation of a closed cell, cross linked polymer foam comprising in a "single stage expansion": a. Pre-mixing of polymer material, crosslinking agent and chemical blowing agent at a temperature which is insufficient to activate crosslinking and decomposition of the chemical blowing agent; b. providing at least one shaped and sized preform comprising pre-mix (a) in an inert atmosphere in an autoclave and subjecting to elevated temperature to initiate both crosslinking and decomposition of the blowing agent; and c. subsequently subjecting to a rapid pressure reduction, which is sufficient to allow full expansion by the blowing gases released in b) above, apparatus therefor, polymer foam obtained thereby and the use thereof. |