Street signs and other products and method for making same from used rubber tires
US5733943A · kind A · utility
Inventor
Key dates
| Filing date | Feb 7, 1996 |
| Grant date | Mar 31, 1998 |
| Priority date | — |
| Expiry date | Feb 7, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31837
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Reground rubber from used tires is mixed with a styrene-butadiene copolymer and polypropylene or polyethylene. The mixture is placed under temperatures and pressures to form a plasticized, moldable material, which is then injected into a mold to form sheet material suitable for street signs and other products. Alternatively, acetal resin is substituted for the polypropylene or polyethylene. Alteratively, a moldable product is formed from 75% reground rubber and 25% styrene-butadiene copolymer, which is then combined with ground polypropylene and virgin rubber, in which the combination is comprised of 25% virgin rubber, by weight. The combination is then partially plasticized under temperature and pressure, and then injected into a mold to form sheet material for street signs and other products.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.