Isotactic propylene copolymer fibers, their preparation and use
US6906160B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 5, 2002 |
| Grant date | Jun 14, 2005 |
| Priority date | — |
| Expiry date | Nov 5, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T442/608
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Fibers comprising a propylene homopolymer or a copolymer of propylene and at least one of ethylene and one or more unsaturated comonomers exhibit desirable properties. The homopolymers are characterized as having 13C NMR peaks corresponding to a regio-error at about 14.6 and about 15.7 ppm, the peaks of about equal intensity. The copolymers are characterized as (A) comprising at least about 60 weight percent (wt %) of units derived from propylene, and (B) having at least one of the following properties: (i) 13C NMR peaks corresponding to a regio-error at about 14.6 and about 15.7 ppm, the peaks of about equal intensity, (ii) a B-value greater than about 1.4 when the comonomer content of the copolymer is at least about 3 wt %, (iii) a skewness index, Six, greater than about −1.20, (iv) a DSC curve with a Tme that remains essentially the same and a Tmax that decreases as the amount of comonomer in the copolymer is increased, and (v) an X-ray diffraction pattern that reports more gamma-form crystals than a comparable copolymer prepared with a Ziegler-Natta (Z-N) catalyst.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.