摘要 |
PURPOSE:To prevent the clogging of a screen mesh by compounding a polypropylene with specified amts. of a hydrotalcite compd. and a magnesium hydrosilicate mineral. CONSTITUTION:100 pts.wt. polypropylene having a mol.wt. distribution (expressed by the ratio of the wt.-average to the number-average mol.wt.) of 7 or lower is mixed with 0.005-0.5 pt.wt. hydrotalcite compd. of formula I (wherein M is Al, Cr, or Fe; (x) is 1-10; (y) is 1-5; and (n) is a positive number) (e.g. a compd. of formula II) and 0.05-5 pts.wt. magnesium hydrosilicate mineral (e.g. talc), pelletized, and extrusion molded at 220 deg.C on an extruder equipped with a 60- to 100-mesh screen. |