Process for preparing high tear-strength polydiene polyurethane
US4053446A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Aug 31, 1976 |
| Grant date | Oct 11, 1977 |
| Priority date | — |
| Expiry date | Aug 31, 1996 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08K3/04
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Polydiene polyurethanes having high tear strength are obtained by using polydiene glycols, prepared with use of lithium-based catalyst, having a number average molecular weight of 1,000 to 5,000 and functionality of 1.8 - 2.1, diisocyanates and chain-extending agents, and by controlling chemical cross-link density being 4 .times. 10.sup.-5 mole/cc and less. When the chemical cross-link density is within the above range, elongation and tensile strength in addition to tear strength of the polyurethane are improved significantly. Furthermore, when 10 - 50 parts by weight of the specified carbon black are added to 100 parts by weight of the mixture of the prepolymer, the chain-extending agent and the additive prior to curing the prepolymer, these mechanical properties of the polyurethane are improved further.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.