Phase Separation and Mechanical Properties of Polyurethane Elastomer with Blended CTO/PCL-3057 Soft Segment
Polyurethane elastomers(PUE)with castor oil(CTO)mass fractions of 30%,50%,60%,70%,and 100%were prepared using a blend of CTO and polycaprolactone terpolymer(PCL-3057)as soft segments,trimethylolpropane as crosslinking agent,and reacting with polymethylene polyphenyl polyisocyanate(PAPI).The influence of soft segment composition on the phase separation structure and mechanical properties of PUE was studied.The results indicated that the formation of hydrogen bonds between hard segments was mainly promoted by CTO,while the formation of hydrogen bonds between soft and hard segments was mainly promoted by PCL-3057.When the content of both accounted for 50%,PUE had good crystallinity,high hydrogen bonding degree,complete microphase separation,and appropriate crosslinking degree,resulting in high mechanical strength and good toughness.The glass transition temperature(Tgs)of PUE soft segment could be reduced by CTO with good flexibility,while it could be reduced by excessive polar groups in PCL-3057.When the content of both groups accounted for 50%,Tgs was the highest.The dynamic mechanical properties of PUE could be significantly improved by PCL-3057 at both low and high temperatures.
NETL
NSTL
万方数据
