To provide a blowing agent improving the foaming magnitude by leaps and bounds by using a specific microcapsules and chemical blowing agent excellent in high foaming property, and a foamable polymer composition containing the blowing agent.
This blowing agent consisting of (A) microcapsules having 1 to 1,000 μm mean particle diameter and containing a low boiling liquid and (B) a chemical blowing agent is provided by showing 100 to 200°C blowing start temperature of the (A) and (B), and 150 to 250°C maximum blowing temperature of the blowing agent. The blowing agent can be used as a foamable polymer composition by being blended with a thermoplastic cross-linkable rubber composition consisting of (C-1) a cross-linkable rubbery polymer and (C-2) a thermoplastic resin.
COPYRIGHT: (C)2007,JPO&INPIT
Norio Kagami
Jun Komatsu