| 摘要 |
PURPOSE:To increase heat resistance and solvent resistance by using a polymer containing specific part by weight of nitrile monomer, non-nitrile monomer and crosslinking agent and preparing a microcapsule volatile expanding agent. CONSTITUTION:(a) 80wt% (hereinafter referred as %), preferably 85-97% of nitrile monomer (Example: acrylonitrile and/or methacrylonitrile, or the like), (b) less than 20%, preferably 10-3% of non-nitrile monomer (Example: methyl methacrylate or the like), (c) 0.1-1%, preferably 0.2-0.5% of crosslinking agent (divinylbenzene or the like) and (d), if necessary, a polymerization initiator are blended together. To this compound, a volatile expanding agent to be gaseous in a temperature of less than softening point of the polymer to be formed is mixed, and the mixture is suspension polymerized in an aqueous medium containing emulsion dispersion auxiliary and the like to prepare microcapsules. Thermal expansion microcapsules are of superb heat resistance and solvent resistance. |
