Articles formed from foamable polypropylene polymer
AssigneeExxonMobil Chemical Patents Inc.
InventorsPawan K. Agarwal, Aspy K. Mehta
Life of this patent
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Abstract
This invention relates generally to articles formed from polypropylene polymer foams and desirably isotactic polypropylene polymer foams. The polypropylene polymers are obtained from metallocene catalysis. The polypropylene polymer has molecular weight distributions and densities that fall within broad ranges. The polypropylene polymer foam may be prepared in a multiple stage polymerization process using the same metallocene component in at least two stages.
Claims12
An article of manufacture comprising a polypropylene polymer foam comprising:
- isotactic propylene homopolymer with a molecular weight distribution in the range from 2.5 to 20.0, hexane extractables of less than 1.0 weight percent, a melt flow rate in the range of 0.2 dg/min to 30.0 dg/min and wherein the polypropylene polymer foam has a density in the range of from 0.3 to 1.0 g/cm3 and
- wherein the isotatic propylene homopolymer comprises a blend of first and second propylene homopolymers, wherein the first propylene homopolymer has a melt flow rate in the range of 0.15 dg/min to 4.0 dg/min and a molecular weight distribution in the range of 1.8 to 2.5, and wherein the second propylene homopolymer has a melt flow rate in the range of 5 dg/min to 1000 dg/min and a molecular weight distribution in the range of 1.8 to 2.5.
An article of manufacture comprising a polypropylene polymer foam having a density in the range of from 0.3 to 1.0 g/cm3 comprising:
- isotactic propylene homopolymer with a molecular weight distribution in the range from 2.5 to 20.0, hexane extractables of less than 1.0 weight percent, a melting point greater than 145° C., and a melt flow rate in the range of 0.2 dg/min to 30.0 dg/min, wherein the isotactic propylene homopolymer further comprises a blend of first and second propylene homopolymers, wherein the first propylene homopolymer has a melt flow rate in the range of 0.15 dg/min to 4.0 dg/min and a molecular weight distribution in the range of 1.8 to 2.5 and comprises from 40 percent to 80 percent of the isotactic propylene homopolymer, and wherein the second propylene homopolymer has a melt flow rate in the range of 5 dg/min to 1000 dg/min and a molecular weight distribution in the range of 1.8 to 2.5 and comprises from 20 percent to 60 percent of the isotactic propylene homopolymer.
Dependencies are inferred from the claim text.