| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a thermally expandable microcapsule which achieves the excellent heat resistance and high expansion ratio and which can be used suitably for the application necessary for the post-processing at high temperatures; and to provide a resin composition, an exapansion-molded item, and an expanded sheet each of which uses the thermally expandable microcapsule. <P>SOLUTION: The thermally expandable microcapsule is included with a volatile expanding agent as a core agent inside a shell comprised of a polymer. The shell comprises a polymer which is formed by polymerizing a monomer mixture containing, based on 100 pts.wt. of a monomer mixture, 95-100 pts.wt. of a nitrile-based monomer (I) containing 70-90 wt.% of acrylonitrile, 0.1-3 pts.wt. of a polymerizable monomer (II) containing two or more double bonds in the molecule, and 0-4 pts.wt. of a polymerizable monomer (III) excluding the nitrile-based monomer (I) and polymerizable monomer (II), and has the degree of crosslinking of 40-80 wt.%. The core agent contains the volatile expanding agent with a vapor pressure at 40°C of 0.15 MPa or more. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
