Patent ID: 9676882
Date: 2017-06-13
CPC Classifications: C08F,C08L

Claim:
1. An in-situ propylene polymer composition comprising at least 50 mole % propylene and at least 1 mol % comonomer, said in-situ propylene polymer composition having a Composition Distribution Breadth Index (CDBI) of 50% or more, a 1% secant flexural modulus of at least 1500 MPa, an Mw/Mn of at least 5, and a melt flow rate of 50 dg/min or more, wherein the CDBI is defined to be the percent of polymer whose composition is within 50% of the median comonomer composition as calculated from the composition distribution curve, wherein the curve is obtained by eluting 100 cm 3 of a polymer solution of about 1 percent concentration through a column of length 164 cm and 1.8 cm ID (inner diameter) packed with non-porous glass beads (2030 mesh) and immersed in a temperature programmable oil bath under 3 atmospheres pressure at 140° C. and maintained at 120° C., subsequently crystallizing the polymer solution by cooling the column to 0° C. at a cooling rate of −20° C./min and maintaining the column temperature at this temperature for 25 min, then eluting the polymer solution by pumping pure solvent, preheated to the temperature of the oil bath, through the column at a flow rate of 27 cm 3 /min, and passing the effluent from the column through a heated line to an IR detector which is used to measure the absorbance of the effluent stream, wherein the absorbance of the polymer carbon-hydrogen stretching bands at about 2960 cm −1 is used to measure the relative weight percent concentration of polymer fractions in the effluent, collecting polymer fractions in 3° C. intervals, followed by raising the temperature at a rate of 1° C./min to 120° C., to obtain a composition distribution curve.