The inclusion of ethylene methyl acrylate copolymer (EMA) during the melt mixing of composites of poly(ethylene terephthalate) (PET) and graphene nanoplatelets (GNP) results in increased melt viscosity and shear stresses acting on the molten composite. This is due to ester groups of the acrylates in the co-monomer unit of EMA reacting via transesterification with PET creating cross-linked structures, as confirmed by solid state ¹³C magic-angle-spinning, nuclear magnetic resonance spectroscopy (¹³C MAS NMR), Fourier transform infrared (FTIR) spectroscopy and, isothermal time sweep oscillatory rheology measurements. The increase in shear stresses assists the exfoliation of the GNP in the PET matrix, resulting in lower electrical and percolation threshold values. The electrical percolation decreased from a volume fraction of 0.017 to 0.005 GNP and an AC conductivity of the PET-GNP composite on inclusion of EMA as high as 10 S/cm attained. The rheological percolation threshold value halved from a volume fraction of ∼0.0237 to ∼0.0117. Both EMA and GNP had a nucleating effect on the PET, as the crystallization temperature (Tc) of PET increased by > 20 °C and the crystalline content (Xc) by >25%.

在聚对苯二甲酸乙二醇酯（PET）和石墨烯纳米片（GNP）的复合材料熔融混合过程中，乙烯丙烯酸甲酯共​​聚物（EMA）的加入会导致熔体粘度增加和作用于熔融复合材料的剪切应力增加。这是由于EMA的共聚单体单元中丙烯酸酯的酯基通过与PET进行酯交换反应而产生了交联结构，如固态¹³ C魔角旋转核磁共振波谱所证实的（¹³C MAS NMR），傅立叶变换红外（FTIR）光谱和等温时扫描振荡流变学测量。剪切应力的增加有助于PET基质中GNP的剥离，从而导致较低的电阈值和渗滤阈值。电渗流从0.017 GNP的体积分数降低到0.005 GNP，并且在包含EMA的情况下，PET-GNP复合材料的AC电导率高达10 S / cm。流变渗透阈值从约0.0237的体积分数减半至约0.0117。EMA和GNP均对PET具有成核作用，因为PET的结晶温度（Tc）升高> 20°C，晶体含量（Xc）升高> 25％。