High surface gloss, co-extruded sheets from propylene polymer materials
US6306518A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 19, 1999 |
| Grant date | Oct 23, 2001 |
| Priority date | — |
| Expiry date | May 19, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31928
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A co-extruded sheet made from olefin polymer materials includes (1) at least one outer layer of (a) a propylene polymer having a melt flow rate of 0.5-15 dg/min, or a graft copolymer comprising a backbone of a propylene polymer material to which is graft polymerized a vinyl monomer, and (b) a nucleating agent having a melting point greater than 265.degree. C. and (2) another layer made from (a) about 5% to about 50% of a high melt strength propylene homopolymer or copolymer, (b) optionally about 5% to about 40% of an inorganic filler, (c) about 2% to about 50% of an olefin polymer composition, and (d) optionally about 5% to about 70% of one or more other olefin polymer materials. The sheet has high surface gloss and good chemical resistance, and can be thermoformed using a melt phase thermoforming process wherein the surface temperature of the nucleated propylene polymer layer is from at least 310.degree. F.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.