| 摘要 |
PURPOSE:To obtain an extrusion molded product which is continuously stably excellent in appearance and physical properties by a method wherein melt extrusion is carried out by specifying molten resin temperature required for melt extrusion of a styrene polymer of a syndiotactic structure, its staying time, and shear speed at an extrusion mouthpiece part. CONSTITUTION:Styrene polymer used for melt extrusion has a syndiotactic structure and its melt viscosity measured under conditions of 100 deg.C and 10/sec in shear speed is 10<3> poise or over to and excluding 10<6> poise. Furthermore, molten resin temperature and staying time at that temperature satisfy a thermal decomposition index of the formula I, and further shear speed at an extrusion mouthpiece is 400/sec or lower. However, in the formula I, SIGMA(t1XDELTAT1) is the thermal decomposion index, (t) is molten resin staying time (min), DELTAT is molten resin temperature-melting point temperature ( deg.C), and (i) is a section number of each melt section. Then, a molded product which is excellent in both physical properties and appearance is continuously stably manufactured. |
