Dehydrocoupling Polymerization: Poly(silylether) Synthesis by Using an Iron β‐Diketiminate Catalyst
Mirela A. Farcaş‐Johnson, Sara H. Kyne, Ruth L. Webster
Abstract
Abstract We describe the iron‐catalyzed polymerizations of diol and silane monomers to obtain fourteen different poly(silylether) products with number average molecular weights ( M n ) up to 36.3 kDa. The polymerization reactions developed in this study are operationally simple and applicable to 1° and 2° silane monomer substrates and a range of benzylic and aliphatic diol substrates as well as one polyol example. The polymers were characterized by IR spectroscopy, DSC and TGA and, where solubility allowed, 1 H, 13 C{ 1 H}, 29 Si{ 1 H} NMR spectroscopies, GPC and MALDI‐TOF were also employed. The materials obtained displayed low T g values (−70.6 to 19.1 °C) and were stable upon heating up to T –5%,Ar 421.6 °C. A trend in T –5%,Ar was observed whereby use of a 2° silane leads to higher T –5%,Ar compared to those obtained using a 1° silane. Reaction monitoring was undertaken by in situ gas evolution studies coupled with GPC analysis to follow the progression of chain‐length growth which confirmed a condensation polymerization‐type mechanism.