Characterization of Thermoplastic Polyurethane (TPU) and Ag-Carbon Black TPU Nanocomposite for Potential Application in Additive Manufacturing

Polymers

Ajit K. Roy¹  Amanda M. Schrand²  Jianjun Hu³  Steven T. Patton³  Lawrence Grazulis³  Chenggang Chen³ 

[1] Materials &Munitions Directorate, Air Force Research Laboratory, Eglin Air Force Base, Valparaiso, FL 45433-7750, USA;Nonstructural Materials Division, University of Dayton Research Institute, Dayton, OH 45469-0050, USA;

关键词: thermoplastic polyurethane;    nanocomposite;    compression;    electromechanical response;    viscoelasticity;    adhesion;    chain relaxation/ordering;    additive manufacturing;   

DOI  :  10.3390/polym9010006

来源: DOAJ

【 摘 要 】

Electromechanical, adhesion, and viscoelastic properties of polymers and polymer nanocomposites (PNCs) are of interest for additive manufacturing (AM) and flexible electronics. Development/optimization of inks for AM is complex, expensive, and substrate/interface dependent. This study investigates properties of free standing films of a thermoplastic polyurethane (TPU) polymer and an Ag–carbon black (Ag-CB) TPU PNC in a lightly loaded low strain compression contact as a rough measure of their suitability for AM. The TPU exhibited high hysteresis and a large viscoelastic response, and sufficient dwell time was needed for polymer chain relaxation and measurable adhesion. A new discovery is that large enough contact area is needed to allow longer time constant polymer ordering in the contact that led to higher adhesion and better performance/reliability. This has previously unknown implications for interface size relative to polymer chain length in AM design. The standard linear model was found to be a good fit for the viscoelastic behavior of the TPU. The PNC exhibited no adhesion (new result), low electrical resistance, and relatively small viscoelastic response. This implies potential for AM electrical trace as well as switch applications.

【 授权许可】

Unknown