| 摘要 |
PURPOSE:To obtain polyurethane elastomer with low temperature dependancy of the bending modulus by reaction injection molding a certain polyol compound and polyisocyanate compound. CONSTITUTION:By mixing two flows of pressurized liquid, one with polyisocyanate compound as its principal component and the other with polyol compound as principal component, then injecting it into a mold, polyurethane elastomer or microcellular polyurethane elastomer can be molded. And by using polyoxialkylenpolyol with 5- 90% in weight of oxibutylene chain as at least one of the polyol compounds, polyurethane elastomer with low temperature dependency of the bending modulus can be obtained. And as the proportion of oxibutylene chain increases, the temperature dependancy decreases, but it is desirable to be within above mentioned figures considering other characteristics and formation reaction of polyurethane. |
