| 摘要 |
PURPOSE:Polymer particles useful for producing bottles, etc. having improved feeding properties during melt molding, and a low bubble admixing ratio, comprising a bulk specific gravity and a variation from diameters corresponding to spheres in specific ranges. CONSTITUTION:In producing chips by extruding a thermoplastic polymer obtained by melt polymerization, etc. preferably an aromatic polyester, especially a polyethylene terephthalate, etc. from a polymerizer into a strand state, cooling it in water, followed by cuttint it laterally, the shape of an extrusion die, the cooling condition, winding speed, etc. are adjusted, to give the aimed particles having >=0.78, preferably >=0.8 bulk specific gravity rho(g/cm<3>) shown by the formula I (A is weight of container g; B is inner volume of container cc; weight of container having test portion g), 0.1-0.24, preferably 0.12-0.22 variation (sigma) from diameters corresponding to spheres shown by the formula II (a, b, and c are thickness, width, and length of particles; V is volume; Dp is diameters corresponding to spheres, and shown by the formula III), preferably 1-5mm. Dp, and having few protrusions, in dies or cylindrical shape. |
