申请人:KANEGAFUCHI KAGAKU KOGYO KABUSHIKI KAISHA
公开号:EP0017086A1
公开(公告)日:1980-10-15
Expandable thermoplastic polymer beads are described which comprise composite beads consisting of a core and a skin and containing a foaming agent; the core being composed of a polymer made from one or more vinyl monomers; the skin being composed of an olefin polymer containing some or all of said vinyl monomers; the foaming agent being a gas or a liquid at ordinary temperatures and pressures and having a boiling point below the softening point of the core material of the beads. Furthermore a process for the production of the expandable thermoplastic polymer beads is described, which comprises suspending grains of a vinyl polymer, a powdered olefin polymer, one or more vinyl monomers and a cross-linking agent in an aqueous medium containing a dispersing agent, and polymerizing the vinyl monomers in the presence of an initiator, wherein a foaming agent is added to the dispersion mixture during or after the polymerization or grains of the vinyl polymer containing the foaming agent are used as starting material, the foaming agent being a gas or a liquid at iordinary temperature and pressure.
所述可膨胀热塑性聚合物珠由复合珠组成,复合珠由芯材和表皮组成,并含有发泡剂;芯材由一种或多种乙烯基单体制成的聚合物组成;表皮由含有部分或全部所述乙烯基单体的烯烃聚合物组成;发泡剂在常温常压下为气体或液体,其沸点低于珠芯材料的软化点。此外,还描述了一种生产可膨胀热塑性聚合物珠的工艺,该工艺包括将乙烯基聚合物颗粒、粉末状烯烃聚合物、一种或多种乙烯基单体和交联剂悬浮在含有分散剂的水介质中、在聚合过程中或聚合后向分散混合物中加入发泡剂,或使用含有发泡剂的乙烯基聚合物颗粒作为起始材料,发泡剂在常温常压下为气体或液体。