| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a production method for polyolefin-based resin foamed particles, wherein the method can obtain foamed particles improved in the uniformity of the foam diameters even if the foam diameter and the foaming ratio are larger than those of conventionals. <P>SOLUTION: The production method for polyolefin-based resin foamed particles, comprises melt-kneading a polyolefin-based resin (A) and a sulfate anhydride (B) represented by formula (I) in an extruder to provide a polyolefin-based resin melt, granulating the resin melt to obtain polyolefin-based resin particles, dispersing in a closed vessel the resin particles in an aqueous dispersant, also impregnating a physical foaming agent into the resin particles under heating to provide foamable resin particles, and then releasing with the aqueous dispersant the foamable resin particles in a lower pressure than the pressure in the closed vessel to foam to provide foamed particles. Formula (I) is expressed by M<SP POS="POST">I</SP>M<SP POS="POST">III</SP>(SO<SB POS="POST">4</SB>)<SB POS="POST">2</SB>, wherein M<SP POS="POST">I</SP>is a univalent cation and M<SP POS="POST">III</SP>is a trivalent metal ion. <P>COPYRIGHT: (C)2013,JPO&INPIT |
