| 摘要 |
PURPOSE:To produce an extruded polyolefin resin foam board with large thickness and cross section by extruding a polyolefin resin compd. contg. chlorodifluoromethane, 1-chloro-1,1-difluoroethane and a specified amt. of a foam shrinkage inhibitor thereby causing the board to have a specified cross section and a specified density variation in the direction of the thickness. CONSTITUTION:In a process wherein a polyolefin resin compsn. contg. chlorodifluoromethane and 1-chloro-1,1-difluoroethane is extruded to produce a foam board, 0.3-5wt.% (based on the compsn.) foam shrinkage inhibitor (e.g. stearic acid mono- or diglyceride) is compounded into the compsn. before the extrusion. The compsn. is then extruded in such a manner that the extruded foam board has a thickness of 35mm or higher, a cross section of 100cm<2> or higher, and a density variation in the direction of the thickness expressed by a specific formula of 15% or lower. |
