Environmentally friendly thermosetting urethane resin system “CUA-4 System”
- Neither of these main agents nor curing agents fall under the regulations of the Law Concerning Special Chemical Substances, the Law Concerning Organic Substances, or the Law Concerning Poisonous and Deleterious Substances(Japan).
- Developed for elastomer (casting) applications.
- Low hardness is also possible.
Comparison of heat resistance between CUA-4 system and common urethane resins
| MOCA Type | CUA-4 system | |||||
|---|---|---|---|---|---|---|
| Main agent | General A type |
General A type |
KC-23-7 | KC-23-4 | KC-23-18 | |
| Curing agent | MOCA | MOCA | CUA-4 | CUA-4 | CUA-4 | |
| Cure condition | Compounding molar ratio | 0.95 | 0.95 | 0.95 | 0.95 | 0.96 |
| Prepolymer temperature (℃) | 90 | 80 | 90 | 90 | 90 | |
| Curing agent temperature (℃) | 120 | 120 | 150 | 150 | 150 | |
| Pot life (min） | 11.5 | 12 | 14（11）※ | （12）※ | 8.5（8）※ | |
| Primary curing temperature (℃)×time(hr) | 100×1 | 100×1 | 110×1 | 105×1 | 105×1 | |
| Secondary curing temperature (℃)× time (hr) | 110×16 | 110×6 | 110×17 | 105×17 | 105×17 | |
| Physical properties | Shore hardness ShoreA | A91 | A91 | A90-92 | A95 | A90 |
| 100%modulus (MPa） | 8.1 | 7.6 | 5.7 | 7.8 | 5.6 | |
| 300%modulus (MPa） | 19 | 13.4 | 9.2 | 14.4 | 9.2 | |
| Tensile strength (MPa） | 45 | 41.6 | 24.8 | 41.5 | 37.7 | |
| Elongation（％） | 392 | 450 | 569 | 488 | 586 | |
| Tear strength (N/mm) | 88 | 100.5 | 82 | 86.2 | 78.8 | |
| Rebound resilience (%） | 48 | 58 | 40.2 | 37.8 | 54.4 | |
| Compression set (%) | 28 | 28 | 40.8 | 46.8 | 28.7 | |
- Pot life: Time to reach 50,000 mPa-s. Figures in parentheses are the time to reach 20,000 mPa-s.