Particulate insulation of chopped polyurea formaldehyde foam - produced by chopping freshly made irregular strands, used for infilling cavity walls

摘要

A particulate insulation matl. is produced from fresh irregular strands of expanded urea formaldehyde resin which are continuously dried and chopped into pieces. The strands may be produced by extrusion or by continuous spread via a doctor comb. As insulation for infill of cavity walls etc. Prefabrication of the matl. under factory conditions ensures proper proportioning of the component reagents. Introduction as dimensionally stable particles avoids subsequent cavitation due to shrinkage of e.g. 2.5-4% volume typical of continuous foam insulation injected in situ.