摘要
采用甲苯-2,4-二异氰酸酯(TDI)对碳纳米管(CNT)进行表面修饰,制得TDI功能化CNT(CNT-TDI),将其分散于4,4′-二苯基甲烷二异氰酸酯中,通过原位聚合法制备CNT-TDI/热塑性聚氨酯弹性体(TPU)复合材料。利用FTIR、XPS和TG等测试手段,表征和分析了CNT-TDI的表面结构;利用旋转流变仪研究了CNT-TDI含量对CNT-TDI/TPU复合材料动态流变性能的影响。结果表明,TDI成功接枝改性CNT,接枝率约17%。动态流变研究结果表明,随CNT-TDI含量增加,复合材料的储能模量(G′)、损耗模量(G″)和复数黏度(η*)均明显提高,G′和G″交点对应的频率向低频移动,损耗峰频率也向低频偏移,说明复合材料的结构性增强,大分子链松弛时间延长;Han曲线上移且逐渐靠近对角线,van Gurp-Palmen曲线下移,说明复合材料的弹性响应逐渐增强;Cole-Cole曲线拖尾现象消失,说明填料的加入降低了TPU基体的微相分离程度。
The functionalized carbon nanotubes(CNT)were prepared by grafting toluene-2,4-diisocyanate(TDI)onto the surface of CNT.Then a series of TDI functionalized carbon nanotubes(CNT-TDI)/thermoplastic polyurethane elastomer(TPU)composites containing various weight percents of CNT-TDI were prepared by prepolymer method via in-situ polymerization.The structure of CNT-TDI was characterized by Fourier-transformed infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS)and thermogravimetric analysis(TG);and the influences of the dosage of CNT-TDI on the rheological properties of CNT-TDI/TPU composites were studied by a rotational rheometer.The results demonstrate that,TDI successfully grafts onto CNT via the reaction between the groups of-NCO and-COOH,and its content is about17%.The dynamic rheological studies show that the storage modulus(G′),loss modulus(G″)and the complex viscosity(η*)of pristine TPU increase significantly with the incorporation of CNT-TDI loading.The crossover of G′and G″and the tanδmove to low frequency with CNT-TDI contents increasing,which indicates the existence of a network structure in CNT-TDI/TPU composites.Han plots shift upward and gradually close to the diagonal line,and the van Gurp-Palmen plots shift downward,which implies that the elastic response exhibits an increasing trend.Cole-Cole curves show that the phase separation of composites decrease due to the presence of CNT-TDI.
作者
白静静
苏会博
刘志伟
BAI Jingjing;SU Huibo;LIU Zhiwei(Department of Materials Engineering, Taiyuan Institute of Technology, Taiyuan 030008)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2018年第24期4386-4391,共6页
Materials Reports
基金
山西省重点扶持学科材料科学与工程项目基金(20160711)
太原工业学院大学生创新创业训练项目(GK20170112)
关键词
碳纳米管
异氰酸酯
表面修饰
热塑性弹性体
流变性能
carbon nanotubes
isocyanate
surface modification
thermoplastic elastomer
rheological properties
