Abstract

A polydimethylsiloxane-α,ω-diol (UHMW-PDMS) with unusually high molecular weight (Mw = 1,395,000 g/mol) and narrow polydispersity (PDI = 1.49), free of monomer or catalyst traces, was obtained in high yield by a scalable process, easy to achieve (bulk anionic ring-opening polymerization of octamethylcyclotetrasiloxane catalyzed by tetramethylammonium hydroxide). Spectral and thermogravimetric analysis confirmed the theoretical structure, purity and thermal stability of the polymer. Individual or aggregated macromolecules were assessed by dynamic light scattering (DLS) and visualized by microscopic methods (TEM, AFM). The mechanical, dielectric, and thermal performances of application interest for this polymer were evaluated on samples of chemically defined elastomer cUHMW-PDMS prepared by condensation crosslinking through the polymer chain ends with tetraethylorthosilicate. The results were compared with those obtained on a lower molecular weight (Mw = 720,100 g/mol, PDI = 1.87) homologue (PDMS) prepared and processed in identical conditions, but also with a commercial silicone elastomer. UHMW-PDMS-based elastomer shows superior results on elastic recovery and stress decay at high elongation, as compared with reference samples.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.