Studies On The Relationship Between Structure And Performance Of Pu Based Elastomer

It is well known that polyurethane based elastomer is a very important material. In this paper, the effects of synthetic method,the soft segements and their molecular weight as well as chemical crosslinking on the mechanical properties of MDI-polyurethane based elastomers were investigated in detail, in order to prepare the title elastomer. The micro-structure and thermally properties of the polyurethane elastomer were characteried with DSC and TG. All the results shouwed that: Firstly, the mechanical properties and thermally properties of the PU elastomer are mainly influenced by structure,in other word, phase separation degree. In addition,The properties of elastomer are also infected by synthetic method, post reaction condition and so on.Secondly, fixed hard segments content,with increasing the molecular weight of soft segments,the phase separation degree of MDI-PU elastomer was enhanced and the mechanical properties were improved remarkably with good tensile strength and lower compress set. Finally, the effect the introducing of chemical crosslinking strcture on phase separation and compress set is very poorly..