PURPOSE: To prepare a copolymer having a high melting point, a high degree of flexibility, tear resistance and contact transparency by producing a propylene- ethylene copolymer in a specific polymerization embodiment using control parameters in multi-reactors in the presence of highly active Ti/Al catalytic series.
CONSTITUTION: Propylene is homopolymerized or copolymerized with a small amount of ethylene in the presence of a Ti catalyst and an organic Al catalyst in a first reactor maintained at 50-100°C and 250-650 psig. The resulting products are fed into a secondary reactor maintained at 25-80°C and 100-500 psig. The resulting products are copolymerized with a small amount of ethylene, so that (a) a control parameter QC is calculated from integral size of a 13C NMR peak corresponding to the molecular structure of a propylene/ethylene copolymer. Additionally, (b) the range of QC for the treatment is defined, and (c) a measurement value QA of a parameter for a copolymer obtained from a secondary reactor is measured and (d) the ethylene feed is adjusted so as to QA is maintained within the range defined in the above (b) to carry out a gas phase polymerization.
MAIKERU BII EDOWAAZU
CHIYAARUZU KEI BIYUURAA
RISA KEI JIYONSON
POORU II BOUEN
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