Functionalized particulate bicarbonate as blowing agent, foamable polymer composition containing it, and its use in manufacturing a thermoplastic foamed polymer

Abstract

A chemical blowing agent for foaming a thermoplastic polymer, for example PVC plastisol or a polymer resin in an extrusion process, comprising a functionalized particulate bicarbonate containing at least one additive, preferably excluding an exothermic blowing agent. The additive may be selected from the group consisting of polymers; inorganic salts; oils; fats; resin acids, any derivative thereof, and salts thereof; amino acids; fatty acids; carboxylic or polycarboxylic acids, soaps; waxes; derivatives thereof; salts thereof; or any combinations thereof. The particulate bicarbonate may be functionalized by spray-drying, coating, extrusion or co-grinding with at least one additive. The functionalized particulate bicarbonate may comprise 50 wt % to less than 100 wt % of the bicarbonate component, and 0.02-50 wt % of the additive. A foamable polymer composition comprising such chemical blowing agent. A process for manufacturing a foamed polymer, such as foamed PVC, comprising shaping and heating the foamable polymer composition, and a foamed polymer obtained by such process.

Dependencies are inferred from the claim text.