摘要 |
An expandable composition comprising: a. a polymeric matrix selected from: a1. a copolymer containing: 90-99.995% of at least one vinyl aromatic monomer; and 0.005-10% by weight of a salt or ester of styrene sulfonic acid; or a2. a polymeric mixture comprising: 92-99.995% by weight of a vinyl aromatic (co) polymer; and 0.005-8% by weight of a product selected from a salt or ester of styrene sulfonic acid and a copolymer of styrene with a C1-C4 salt or ester of styrene sulfonic acid; and b. 1-10% by weight, calculated with respect to the polymeric matrix (a), of an expanding agent. |