Synthesis And Properties Of Damping Material Based On Polyurethane Elastomers

Polyurethane elastomers(PUEs) were well used as high performance damping material due to its characteristic properties of phase separation betewwen soft and hard segment. As a part of foundational investigation of damping material based on PUE, in this paper, the effect of chmeical composes and synthesis parameter, including hard segment/soft segment ratio, MDI isomers, polyols, NCO/OH ratio on the mechanical and damping performance of the resultant PUE were studied by FTIR, differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) respectively. After that, AO-80/PU composites were synthesized through in-situ polymerization,and the effects of AO-80 on the performances of resultant composites have been studied. The experiment results indicated:1. Increasing the hard segment content increased the crystallinity of hard segment and improved the pahse separation between hard and soft segment, which increased mechanical performance but decreased the tanδof the resultlant PUEs. The optimized NCO/OH ratio was 1.05.2. The degree of hydrogen bonding and crystallinity within hard segment were decreased with increasing the content of 2,4'-MDI isomer. This promoted the phase mixing between hard segments and soft segments and subsequently improved the Tgs and tan8 of the resultlant PUEs dramatically.3. By setting a constent hard segment content of 40%, the phase compatibility was increased by introduing DL400 to MDI/DL2000/BDO system, which improved the tanδbut decreased the mechanical performance of the resultant PUEs.4. AO-80 could partly react with diisocyanate MDI. By compositing, AO-80 can increase the damping performance of AO-80/PUE composites. In addition, AO-80 which reacting with diisocyanate MDI can improved the tanδof the resultant composites further.5. By mixing molding, the mechanical and damping performance of AO-80/PUE composites can be both improved.