Extremely Rapid Polythioether Synthesis in the Presence of TBD

Abstract

A straightforward, novel, and extremely rapid method is developed for the synthesis of polythioether based on the reaction of dimethyl acetylenedicarboxylate with electron-deficient triple bond and 1,6-hexanedithiol in CHCl3 using an organobase 1,5,7-triazabicyclo[4.4.0]dec-5-ene at room temperature. The influence of various parameters, such as concentration of monomers, solvent, catalyst, and reaction time, on the polymerization was investigated through kinetic studies. Polythioether with molecular weight up to ∼50 kDa was quantitatively achieved in 1 min, under the optimum experimental conditions. Various dithiol compounds were then reacted with dimethyl acetylenedicarboxylate to enhance polymer diversity. Following, three propiolate compounds were reacted with 1,6-hexanedithiol to explore their ability for polythioether synthesis, but low to moderate molecular weights were achieved compared to those with dimethyl acetylenedicarboxylate. The versatility of these polythioethers was shown by postpolymeriz...