A special class of smart material was developed using shape memory polyurethane (SMPU) elastomer and graphene nanoplatelets (GNPs) via melt-blending process using micro-compounder. The shape recovery of the developed composites was studied under microwave irradiation. The nanocomposites were developed having 0.2, 0.4, 0.6, and 0.8 phr GNPs in the SMPU matrix. The effects of GNP reinforcement on morphology, shape memory effects, and viscoelastic properties of the composites were investigated. The recovery stress of virgin SMPU increased with reinforcement and maximized on the incorporation of 0.6 phr GNPs. The deformation-induced shape memory creation process influenced significantly the recovery stress of composites as compared to virgin SMPU. The recovery stresses of SMPU at 50, 75, and 100% strain were 1.5, 1.7, and 1.9 MPa, whereas the values of GNP-SMPU composites were 3.2, 3.4, and 4.1 MPa corresponding to 0.6 phr GNP reinforcement. The value of storage modulus above the glass transition temperature of SMPU increased from 9.2 to 15.1 MPa on the addition of 0.6 phr GNPs. The peak of the damping factor, tan δ shifted toward higher temperatures with the increased GNP content. The morphological study confirms the uniform dispersion of GNPs in the SMPU matrix. The microwave-induced heating of 0.8 phr GNP composite shows 80% shape recovery in 60 s, which is faster than convectional heating.

使用形状记忆聚氨酯（SMPU）弹性体和石墨烯纳米片（GNP）通过使用微复合物的熔融共混工艺开发了一种特殊的智能材料。在微波辐射下研究了所开发复合材料的形状恢复。开发出在SMPU基质中具有0.2、0.4、0.6和0.8phr GNP的纳米复合材料。研究了GNP增强对复合材料的形貌，形状记忆效应和粘弹性的影响。原始SMPU的恢复应力随着增强而增加，并在掺入0.6 phr GNP时达到最大。与原始SMPU相比，变形诱导的形状记忆创建过程显着影响了复合材料的恢复应力。SMPU在50％，75％和100％应变下的恢复应力分别为1.5、1.7和1.9 MPa，而GNP-SMPU复合材料的值为3.2、3.4和4.1 MPa，相当于0.6 phr GNP增强。添加0.6 phr GNP后，SMPU的玻璃化转变温度以上的储能模量值从9.2增至15.1 MPa。随着GNP含量的增加，阻尼系数的峰值tanδ向更高的温度移动。形态学研究证实了GNP在SMPU基质中的均匀分散。微波诱导的0.8 phr GNP复合材料的加热在60 s内显示80％的形状恢复，比对流加热更快。随着GNP含量的增加，tanδ向更高的温度移动。形态学研究证实了GNP在SMPU基质中的均匀分散。微波诱导的0.8 phr GNP复合材料的加热在60 s内显示80％的形状恢复，比对流加热更快。随着GNP含量的增加，tanδ向更高的温度移动。形态学研究证实了GNP在SMPU基质中的均匀分散。微波诱导的0.8 phr GNP复合材料的加热在60 s内显示80％的形状恢复，比对流加热更快。