改性石墨烯/聚氨酯复合乳液的合成及性能表征

通过逐步聚合反应将改性氧化石墨烯(DIGN)接枝到水性聚氨酯(WPU)链段中,制备得到DIGN/WPU纳米复合乳液。通过IR、AFM、SEM对氧化石墨烯(GO)、DIGN、WPU及DIGN/WPU纳米复合材料的结构进行表征;并研究了DIGN用量对乳液粒径,流变性能及其胶膜的热稳定性和力学性能的影响。结果表明:DIGN的引入使得乳液具有了假塑性流体特性,并随DIGN含量的增加,乳液黏度,粒径及分布指数增大,纳米复合材料的热稳定性明显改善;当w(DIGN)=1wt%时,拉伸强度增加80.33%,杨氏模量提高192.11%,断裂伸长率下降了42.74%。

Preparation and Property of Water-based modified graphene /polyurethane composite emulsion

Water-based graphene/polyurethane nanocomposite emulsion (DIGN/WPU) was prepared by stepwise polymerization, grafted isocyanate functionalized graphene (DIGN) to the water-borne polyurethane (WPU) chain segment. Fourier transform infared spectrometer (FTIR), Atomic Force Microscope (AFM) and scanning electron microscope(SEM) were used to characterize the structure of the Graphene oxide (GO), DIGN, WPU and DIGN/WPU composites. Simultaneously, effects of content of DIGN on emulsion particle size, rheological properties and thermal stability and mechanical properties of the films were systematically studied. The result showed that the nanocomposite emulsion behaves pseudo-plastic fluid with shear-thinning property, and with the increase of the content of DIGN emulsion viscosity, particle size and distribution index increased, the thermal stability of the nanocomposites are obviously improved. When the content of DIGN loading reaches 1%, the tensile strength increased by 80.33%,Young"s modulus increased by 192.11%, elongation at break decreased by 42.74%.