聚(氨酯-脲-酰胺)热塑性弹性体的合成及表征

Synthesis and Characterization of Poly(urethane-urea-amide) Thermoplastic Elastomers

以双端氨基的尼龙1212预聚物(OPA)为硬段、异氰酸酯封端的聚醚型聚氨酯预聚物(OPU)为软段,通过改变软、硬段的摩尔比制得了不同相对分子质量的聚(氨酯-脲-酰胺)热塑性弹性体(PUUA)。通过傅里叶变换红外光谱(FT-IR)考察了OPU合成过程中-NCO基团与C-O-C醚键的相对强度变化,进而确定了合成OPU的反应时间为60 min。通过核磁氢谱和FT-IR确定了产物结构。凝胶渗透色谱法(GPC)测试结果表明,硬、软段摩尔比在1.2~1.5范围内,产物重均分子量可在(1.82~3.59)×104范围内调控。差示扫描量热分析(DSC)结果表明,随着硬、软段摩尔比由1.2提高至1.5,硬段的熔点由185℃降低至174℃,结晶温度由167℃降低至138℃,但OPU软段的熔点和结晶温度基本不变。PUUA的力学性能测试结果表明,其拉伸强度为28 MPa,断裂伸长率可达417%,缺口冲击未能冲断,是一种性能优异的热塑性弹性体。

Poly(urethane-urea-amide)elastomers(PUUA)with different molecular weight were prepared using amino-terminated nylon 1212 prepolymer(OPA)as hard segment and isocyanate-terminated polyether polyurethane prepolymer(OPU)as soft segment.The molecular weight of PUUAs was determined by different mole ratios of soft and hard segments.The relative intensity changes of-NCO group and C-O-C ether bond during the synthesis of OPU were investigated by Fourier transform infrared spectroscopy(FT-IR),and then the reaction time for the synthesis of OPU was determined to be 60 min.The structures of PUUAs were characterized by 1H-NMR and FT-IR.Gel permeation chromatography(GPC)test results show that the average molecular weight of the PUUAs could be controlled within the range of(1.82~3.59)×10^(4) by controlling the mole ratio of hard and soft segments in the range of 1.2~1.5.DSC results show that with the increase of the mole ratio of the hard and soft segments from 1.2 to 1.5,the melting temperatures of the hard segment are decreased from 185℃to 174℃,and the crystallization temperatures are decreased from 167℃to 138℃,but at the same time,the melting and crystallization temperature of the OPU soft segments is still maintained.The tensile strength of PUUA is 28 MPa,the elongation at break can reach 417%,and it has not been broken in notch impact test.The results show that PUUA is a thermoplastic elastomer with excellent properties.