公开(公告)号：US20070043177A1

公开(公告)日：2007-02-22

申请号：US10553788

申请日：2004-05-05

申请人： William Michie ,  Anthony Neubauer ,  Brad Cobler ,  Carl Baker

发明人： William Michie ,  Anthony Neubauer ,  Brad Cobler ,  Carl Baker

IPC分类号： C08G85/00

CPC分类号： C08F210/16 ,  B29C47/0014 ,  B29C47/0021 ,  B29C47/38 ,  B29C47/404 ,  C08F8/00 ,  C08L23/0815 ,  C08L2205/02 ,  C08L2308/00 ,  Y10S525/938 ,  C08F10/02 ,  C08F2/001 ,  C08L2666/06 ,  C08F210/14 ,  C08F2500/12 ,  C08F2500/07 ,  C08F2500/04 ,  C08F2500/09 ,  C08F2500/26

摘要： The present invention includes a multimodal polyethylene composition has (1) a density of at least about 0.940 g/cm3 as measured by ASTM Method D-1505; (2) a melt flow index (I5) of from about 0.2 to about 1.5 g/10 min (as measured by ASTM D-1238, measured at 190° C. and 5 kilograms); (3) a melt flow index ratio (I21/I5) of from about 20 to about 50; (4) a molecular weight distribution, Mw/Mn, of from about 20 to about 40; (5) a bubble stability measured on specified equipment according to specified conditions for a film of about 6×10−6 m thickness of at least about 1.22 m/s line speed, at least about 45 kg/hr (0.013 kg/sec) output rate, or at least about 0.5 lb/hr/rpm (0.0000011 kg/s/rps) specific output rate or a combination thereof; the composition comprising; and (6) a dart impact on 12.5 micron (1.25×10−5 m) film of at least 300 g; measured according to ASTM 1709, Method A; (A) a high molecular weight fraction which; (a) is present in an amount of from about 30 to about 70 weight percent (based on the total weight of the composition); (b) has a density of at least about 0.860 g/cm3 as measured by ASTM D-1505; (c) has a melt flow index (I21) of from about 0.01 to about 50 g/10 min (as measured by ASTM D-1238, measured at 190° C. and 21.6 kilograms); and (d) a melt flow index ratio (I21/I5) of from about 6 to about 12; and (B) a low molecular weight fraction which; (a) is present in an amount of from about 30 to about 70 weight percent (based on the total weight of the composition); (b) has a density of at least about 0.900 g/cm3 as measured by ASTM D-1505; (c) has a melt flow index (I2) of from about 0.5 to about 3000 g/10 min (as measured by ASTM D-1238, measured at 190° C. and 2.16 kilograms); (d) a melt flow index ratio (I21/I5) of from about 5 to about 15; and (e) is prepared using a mole ratio of alpha olefin to ethylene of less than or equal to about 0.001:1. The invention also include a process for producing a multimodal ethylene polymer, which process comprises the following steps: (1) contacting in a first gas phase fluidized bed reactor under polymerization conditions and at a temperature of from about 70° C. to about 110° C., a titanium magnesium catalyst precursor, cocatalyst, and a gaseous composition, the gaseous composition having; (i) a mole ratio of alpha-olefin to ethylene of from about 0.01:1 to about 0.8:1; and optionally (ii) a mole ratio of hydrogen to ethylene of from about 0.001:1 to about 0.3:1, to produce a high molecular weight polymer(HMW); and (2) transferring the HMW polymer from step 1 to a second gas phase fluidized bed reactor under polymerization conditions and at a temperature of from about 70° C. to about 110° C., with a gaseous composition having; (i) a mole ratio of alpha-olefin to ethylene of from about 0.0005:1 to about 0.01:1; and (ii) a mole ratio of hydrogen (if present) to ethylene of from about 0.01:1 to about 3:1 to form a polymer blend