PURPOSE: To provide a process for producing an in situ blend which can be extruded into a film having an appearance grade tolerable as a commercial product.
CONSTITUTION: Ethylene, an α-olefin comonomer, and a magnesium/titanium catalysts system are brought into contact with each other under polymerization conditions in each of two fluidized bed reactors connected in series. (a) In the first reactor for producing a low-MI copolymer, (1) the α-olefin is present in an amount of about 0.01 to about 0.4 mol per mol of ethylene, (2) the ethylene partial pressure is at least 40 lb./in2. (b) In the second reactor for producing a high-MI copolymer, (1) the α-olefin is present in an amount of about 0.005 to about 0.6 mol per mol of ethylene, (2) hydrogen is present in an amount of about 1 to about 3 mol per mol of ethylene, and (3) a hydrocarbylaluminum promoter containing diethylzinc in an amount of about 2 to about 40 mol per mol of the titanium is added.
MAIKERU UIRIAMU TEIRUSUTON
TOMASU EDOWAADO SUPURITSUGUZU
BAAKUHAADO ERITSUKU WAGUNAA
ARAKARUGUDO BENKATAPASHIA RAMA
