Patent ID: 6303668
Filing Date: 2001-10-16
Classification: C08J,C09K,C11D,C23G

Abstract:
In a method for manufacturing a polymeric cellular foam, the improvement which consists in selecting a blowing agent comprising a composition forming a minimum boiling point binary azeotrope or pseudo-azeotrope at atmospheric pressure, said composition being selected from(a) a composition consisting of from approximately 47 wt % to 70 wt % of 1,1,1,3,3-pentafluorobutane and from approximately 30 wt % to 53 wt % of n-pentane;(b) a composition consisting of from approximately 61 wt % to 81.5 wt % of 1,1,1,3,3-pentafluorobutane and from 18.5 wt % to 39 wt % of cyclopentane;(c) a composition consisting of form approximately 30 wt % to 61 wt % of 1,1,1,3,3-pentafluorobutane and from approximately 39 wt % to 70 wt % of isopentane; and(d) a composition consisting of from approximately 76 wt % to 91.5 wt % of 1,1,1,3,3-pentafluorobutane and from approximately 9.5 wt % to 24 wt % of n-hexane.