Synthesis and Characterization of Thermoplastic PDMS
Authors: Ahmed Kumkum , Shiblee MD Nahin Islam , Thundat Thomas , Nagahara Larry A. , Kawakami Masaru , Furukawa Hidemitsu , Khosla Ajit 
Published: February 2020

Polydimethylsiloxane (PDMS), a silicone based thermosetting elastomer, has been widely used because of its biocompatibility, low cost, low toxicity, high oxidative and thermal stability, optical transparent, low permeability to water, low electrical conductivity, and ease of micropatterning [1, 2]. Various nanocomposites have been fabricated employing PDMS, that are electrically conductive [3] magnetic [4, 5, 6] in nature and can be easily micromolded using conventional hybrid soft lithography techniques [7, 8].

With the emerge of 3D printing, we present synthesis of thermosplastic PDMS, which can be 3D printed and is recyclable. The crosslinked recyclable PDMS was prepared using the reaction between PDMS-diglycidyl ether（17.6mmol） and pripol 1017 (17.6mmol) with Zn(OAc) (0.88mmol)2 as the catalyst. The crosslinking process completed after 12-hour at 130 °C [8]. The prepared PDMS film and sheets were cut to small pieces using a palletizer and passed through a filament extruder to make PDMS filament. Their mechanical, thermal and solvent resistance properties were characterized and appropriate conditions for 3D printing has been optimized.

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