| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing preliminary expanded particles of polypropylene-based resin, capable of reducing a heated steam pressure for forming, necessary for obtaining ≥75% melt-adhesion rate on foam-molding within a mold of the preliminary expanded particles of the polypropylene-based resin consisting of the polypropylene-based resin particles prepared by an underwater cut method. SOLUTION: This method for producing the preliminary expanded particles of the polypropylene-based resin is provided by obtaining the polypropylene-based resin particles by extruding the polypropylene-based resin containing ≥1 pt.wt. and ≤20 pts.wt. polyethylene-based resin having ≥10 and ≤2,000 mPa s melt viscosity at 140°C based on 100 pts.wt. polypropylene-based resin into water from a nozzle of a die, cutting by a cutter blade rotating in the water, under conditions that the shearing speed of the molten polypropylene-based resin composition in passing through the nozzle of the die is ≤95,000 sec<SP>-1</SP>and the apparent melt viscosity of the molten polypropylene-based resin is ≥70,000 mPa s, and then obtained from the above polypropylene-based resin particles. COPYRIGHT: (C)2010,JPO&INPIT
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