Heat-expandable microspheres, composition, and formed product

Abstract

Provided are heat-expandable microspheres which have high expansion performance to exhibit highly thermoresponsive expansion behavior in short heating time and the application thereof. The heat-expandable microspheres are composed of a thermoplastic resin shell and a blowing agent encapsulated therein and vaporizable by heating. The thermoplastic resin is a polymer of a polymerizable component containing a nitrile monomer, and the nitrile monomer contains acrylonitrile and methacrylonitrile in a ratio of 100 parts by weight/40 parts by weight to 80 parts by weight. The blowing agent contains a blowing agent (a) having a specific heat in the range from 0.8 J/g·K to 2.0 J/g·K. Also disclosed is a composition containing the heat-expandable microspheres and a formed product manufactured by forming the composition.

Dependencies are inferred from the claim text.