| 摘要 |
PURPOSE:To prevent resin particles from adhering to each other by fusion when they are heated above the m.p. of the resin, by adding carbon powder as a dispersant in carrying out a heat-treatment of polyolefin resin particles by dispersing in a dispersing medium. CONSTITUTION:100pts.wt. particle of a polyolefin resin such as polyethylene or polypropylene is mixed with about 0.001-5pts.wt. carbon powder as a dispersant, particle diameter of about 10-500mum, such as carbon black or graphite. Then, the resin particles mixed with the carbon powder are dispersed in a medium which does not dissolve the resin particle (e.g., water, ethylene glycol) and heated to effect a desired chemical treatment (e.g., crosslinking) or a physical treatment (e.g., pre-expansion). In this way, it becomes possible to carry out a desired heat treatment suitably without causing adhesion of resin particles by fusion when they are heated to a temperature above the m.p. of the resin. |
