Back to results
US 10,766,981 B2Granted
Bimodal polypropylenes and method of making same
AssigneeExxonMobil Chemical Patents Inc.
InventorsRohan A. Hule, Sudhin Datta, Yi Ping Ni
Life of this patent
Estimating the term…
Abstract
Bimodal polypropylene compositions and a process to form melt blended bimodal polypropylene compositions comprising combining at least two polypropylenes in at least a two-pass process, and forming a bimodal polypropylene composition having a Flexural Modulus (190° C., 1% secant) of at least 1700 MPa, as well as one or more other selected properties. These compositions are suitable for thermoformed articles and injection molded articles, any of which may be foamed.
Claims31
A process to form bimodal polypropylene compositions comprising:
- 1) combining at least two polypropylenes comprising:
- a) a high molecular weight polypropylene, HMW PP, having a weight average molecular weight (Mw) of 300,000 g/mole or more, and a MWD within the range from 2.0 to 4.5;
- and
- b) a low molecular weight polypropylene, LMW PP, having a weight average molecular weight (Mw) of 300,000 g/mole or less, and a MWD within the range from 2.0 to 4.5, in at least a two-pass process, and
- 2) forming a bimodal polypropylene composition having a Flexural Modulus (190° C., 1% secant) of at least 1700 MPa, wherein the Flexural Modulus of the bimodal polypropylene composition is equal to or at least 5% greater than the HMW PP Flexural Modulus alone, and the bimodal polypropylene composition has one or more of the following characteristics:
- (a) a melt flow rate (MFRbPP, 230° C., 2.16 kg) within the range from 2 g/10 min to 200 g/10 min;
- and/or
- (b) a combined molecular weight distribution (MwbPP/MnbPP, MWDbPP) within the range from 2.5 to 20.0, and/or
- (c) a ΔMw, the Mw difference between at least two polypropylenes, of at least 100,000 g/mole;
- and
- 3) injection molding or blow molding articles from the bimodal polypropylene composition.
8 more elements
A polypropylene composition comprising:
- a) 35 wt. % to 60 wt. % of a high molecular weight polypropylene having a weight average molecular weight of 400,000 g/mole or more, and a MWD within the range from 2.0 to 4.5;
- and
- b) 40 wt. % to 65 wt. % of a low molecular weight polypropylene having a weight average molecular weight of 300,000 g/mole or less, and a MWD within the range from 2.0 to 4.5, based on a combined weight of the high and low molecular weight polypropylene,
- said polypropylene composition having a Flexural Modulus (190° C., 1% secant) of at least 1700 MPa, wherein the Flexural Modulus of the polypropylene composition is equal to or at least 5% greater than a Flexural Modulus of the high molecular weight polypropylene alone, and wherein the high molecular weight polypropylene and the low molecular weight composition have been melt blended together and the weight average molecular weight of the high molecular weight polypropylene is at least 200,000 g/mol greater than weight average molecular weight of the low molecular weight polypropylene.
1 more element
Dependencies are inferred from the claim text.