In order to improve the toughness,heat and humidity resistance of castor-oil-based polyurethane(CO—PU),the PU samples with symmetrical bishydrophobic alkyl groups were prepared by using a mixed soft segment composed of CO and poly(adipic acid-2-butyl-2-ethyl-1,3-propanediol)glycol(PBEPG).The results of Fourier transform infrared spectroscopy(FTIR),dynamic mechanical analysis(DMA)and thermogravimetry analysis(TG)reveal that,with the increase of PBEPG mass fractions,the degree of microphase separation between soft and hard segments of PU is improved,the glass transition temperature of PU is decreased,and the maximum thermal degradation temperature of PU is increased.When CO∶PBEPG(mass ratio)is 70∶30,the PU sample exhibits ductile fracture,its tensile strength is 21.4 MPa,and its tensile strength remains 90%after aging at relative humidity of 100%and 100℃for 60 h,showing high mechanical strength,heat and humidity resistance.
关键词
蓖麻油基聚氨酯/烷基侧基/耐湿热性能/氢键
Key words
Castor-Oil-Based Polyurethane/Alkyl Side Group/Heat and Humidity Resistance/Hydrogen Bonding
维普
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