Fabrication of Novel Thermoplastic Polyurethane Elastomers With Both Heat Resistance and Conductivity Prepared From p-Phenylene Diisocyanate

Conductive polyurethane (CPU) with excellent processability has broad prospects in the communication field. However, the poor thermal stability of polyurethane (PU) limits its application. To solve this problem, a type of CPU with heat resistance was synthesized from p-phenylene diisocyanate (PPDI), poly-(tetramethylene ether) glycol (PTMG), aniline trimer (AT), and subsequently doped with camphorsulfonic acid (CSA). Besides, both polydimethylsiloxane (PDMS) and polycarbonate diol (PCDL) were introduced into CPU backbones, and PPDI-based CPU (PCPU) was synthesized with a high reaction efficiency of 94%. The structure of PCPU was confirmed by FT-IR, 1 H NMR, and GPC. The microphase separation structure, thermal stability, mechanical properties, and conductive performances were investigated using multiple characterization techniques such as DSC, XRD, TGA, DMA, and so on. The addition of PDMS promoted microphase separation and significantly improved the thermal stability of PCPU. Meanwhile, introducing PCDL into soft segments might increase the hydrogen-bond content in the PU system. When the molar ratio of PTMG to PCDL is 3:1, the thermal stability and mechanical properties of PCPU can be maximized. Furthermore, the conductive segments composed of AT formed a spatial conductive network within the PCPU. Obviously, such highly heat-resistant PCPU showed considerable potential for being used in high-temperature environments.