PROCESS FOR PREPARING HIGHLY CRYSTALLINE POLYPROPYLENE

• Main Authors: MATSUDA KIYOSHI, NAMIKI ICHIRO, CHIBA HIROMASA, HANARI TOHRU, MORI KINYA
• Format: Patent
• Language: English
• Published: 16.08.1995
• Edition: 6
• Subjects: CHEMISTRY; COMPOSITIONS BASED THEREON; COMPOSITIONS OF MACROMOLECULAR COMPOUNDS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; TECHNICAL SUBJECTS COVERED BY FORMER USPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ARTCOLLECTIONS [XRACs] AND DIGESTS; THEIR PREPARATION OR CHEMICAL WORKING-UP

A highly crystalline polypropylene (PP) from which highly stiff molded products can be produced and also which can be used for use applications for which conventional PP could not have been used is provided, which PP is chracterized by the following conditions (A) and (B): (A) its melt flow rate (MFR) and absorbance ratio according to the method of infrared absorption spectra (IR tau ; an absorbance ratio of a wave-number of infrared rays of 997 cm<-> to that of 973 cm<-> ) satisfy an equation of IR- tau >/=0.0203 log MFR + 0.950 and its MFR is in the range of 0.1 to 200; and (B) when a dilute solution of the PP dissolved in xylene is slowly cooled with stirring, an initially deposited component in 2 to 3% by weight has an IR- tau value of 0.97 or more and the weight average M.W. (Mw1) of the deposited components and that (Mwo) of the PP have a ratio of 3 or more.