Multilayer pipe
US6187402A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 3, 1998 |
| Grant date | Feb 13, 2001 |
| Priority date | — |
| Expiry date | Sep 3, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31938
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A multilayer pipe having improved resistance to rapid crack propagation is described.; The pipe consists of at least two layers of different propylene plastic materials, which are so selected and combined that the pipe has a resistance to rapid crack propagation, measured as the critical temperature, which is equal to or lower than 0.degree. C. The pipe is made of polypropylene plastic, and at least one of the layers of the pipe comprises a polypropylene plastic, which is selected from a propylene contanig from 1.0 to 10.0% by weight of ethylene or C.sub.4 -C.sub.10 -.alpha.-olefin repeating units and having an MFR.sub.2 value of between 0.05 and 0.40 g/10 min or an elastromer-modified polypropylene containing from 1.0 to 30% by weight of ethylene or C.sub.4 -C.sub.10 -.alpha. olefin repeating units and having an MFR.sub.2 value of between 0.05 and 50 g/10 min.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.