process for preparation of a resin hard foam cell a7's average gross

摘要

Disclosed is a process for producing medium to coarse cell rigid phenolic resin foams having improved abrasion wear by adding to a mixture of phenol-formaldehyde resin, hardening and foaming agent, prior to foaming an additive dispersion consisting of a copolymer of fumaric acid diesters and of a vinyl aromatic compound such as styrene and optionally an olefin such as propylene.