氧化石墨烯/天然橡胶复合材料的制备与性能

采用己内酰胺（CPL）改性氧化石墨烯（GO）（CPL-GO），与天然橡胶（NR）复合后通过熔融共混法制备了CPL-GO/NR复合材料。考察了CPL-GO用量对CPL-GO/NR复合材料物理机械性能、界面相互作用和气体阻隔性能的影响。结果表明，CPL改性GO后，X射线衍射层间距增加，片层堆砌更为松散，CPL-GO与水接触角增至91.2°。当CPL-GO的质量分数为2.0%时，CPL-GO/NR复合材料的拉伸强度为26.1 MPa，较纯NR提高了50.9%。随着CPL-GO用量的增加，复合材料的储能模量增加，损耗因子的峰值减小，表明GO经CPL表面改性后与NR复合，增强了两相界面间的相互作用，从而提高了复合材料抵抗变形的能力。在40 ℃下，当CPL-GO的质量分数为3.0%时，CPL-GO/NR复合材料的气体渗透系数较纯NR下降了57.1%。

Preparation and properties of graphene oxide/natural rubber composites

Graphene oxide(GO) was modified with caprolactam (CPL) to obtain CPL-GO, then CPL-GO/natural rubber (NR) composites were prepared by melt blending method after combining with NR. The effect of amount of CPL-GO on the physical and mechanical properties, interfacial interaction and gas barrier properties of CPL-GO/NR composites were investigated. The results showed that the spacing of X-ray diffraction layers of CPL-GO increased, the GO lamellar stacking became looser, the water contact angle of CPL-GO increased to 91.2°, which contributed to the good dispersion of GO in the rubber matrix. When the mass fraction of CPL-GO was 2.0%, the tensile strength of CPL-GO/NR composite was 26.1 MPa, which was 50.9% higher than that of pure NR. With the increasing amount of CPL-GO, the storage modulus of the composite increased, and the peak value of the loss factor decreased. It indicated that the composite of GO after surface modification of CPL compounded with NR enhanced the interaction between the two-phase interfaces, which improved the ability of the composite to resist deformation. At 40 ℃, when the mass fraction of CPL-GO was 3.0%, the gas permeability coefficient of CPL-GO/NR composite decreased by 57.1% compared with that of pure NR.