Ethylene polymer and fuel tank comprising the same
US5547722A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 1995 |
| Grant date | Aug 20, 1996 |
| Priority date | — |
| Expiry date | Mar 31, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31928
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
An ethylene homopolymer or copolymer comprising ethylene and not more than 10% by weight of an .alpha.-olefin having from 3 to 20 carbon atoms and a fuel tank obtained therefrom are disclosed, said ethylene homopolymer or copolymer having (1) an intrinsic viscosity [.eta.] of from 2 to 6 dl/g, (2) a density of from 0.945 to 0.970 g/cm.sup.3, (3) an R value of from 2.5 to 4, said R value being defined as a .sigma..sub.2 /.rho..sub.1 ratio, wherein .sigma..sub.1 and .sigma..sub.2 mean stress in elongation with a strain at 2 sec and 4 sec, respectively, under a flow at an elongational strain rate .epsilon. of 0.5 sec.sup.-1, and (4) a relationship between high-velocity impact strength (HRI-IZOD) measured at -30.degree. C. and a melt index under a load of 21.6 kg (HLMI) satisfying formula: EQU HRI-IZOD.gtoreq.-log HLMI+1.15 The ethylene polymer exhibits high melt tension and excellent molding properties such as uniform stretchability in blow molding to provide molded articles, such as a fuel tank, having excellent mechanical characteristics, such as high stiffness and high impact resistance, and excellent fire resistance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.