A Straightforward Method to Synthesize Telechelic Poly(dimethylsiloxane)s

M.M.S. LENCINA; C. MÜLLER; V. HANAZUMI; F.L. REDONDO; M.D. NINAGO; C. VITALE; M.A. VILLAR; A.E. CIOLINO

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Encuentro; Annual Meeting of the Belgium Polymer Group (BPG 2017); 2017

Belgium Polymer Group (BPG)

One of the goals of polymer chemistry is developing new methodologies for the controlled synthesis of polymers with predictable, well-defined structures. Living anionic polymerization provides one of the best methodologies for synthesizing complex macromolecular structures like a,w-telechelic polymers. these macromolecules are obtainedby different synthetic methods, which usually involve the titration of alkyllithium over double diphenyl ethylene derivatives (DDPE). In this work we report the synthesis of a,w-telechelic PDMS by employing a novel bifunctional initiator, obtained from a commercial available siloxane precursor, poly(dimethylsiloxane) diglycidylether terminated (PDMS-DGE). the synthetic strategy involves high-vacuum reaction of sec-Bu-Li+ with DPE, and subsequently with PDMS_DGE to promote the nucleophilic ring-opening of the epoxide ends. The resulting bifunctional initiator was then employed in the polymerization of hexamethylciclotrisiloxane (D3) by using conventional anionic polymeriztion methods. Silane (-SiH), vinyl (-CH=CH2), hydroxil (-OH), trimethyl and even methacryloil ended PDMS were obtained. From SEC analysis, narroe molar mass distributions (Mw/Mn ≤ 1.3) and good control over the resulting number-average mnolar masses were observed. In addition, 1H-NMR and FTIR characterization confirmed the presence of the targeted functional groups in the resulting polymers.