Role of Initiator Structure on Thiol-Ene Polymerization: A Comprehensive Theoretical Study

Abstract

In this study, the effects of initiator structure on thiol-ene polymerization were investigated with two initiators, four thiols, and eight monomers by utilizing the M06-2X/6-31++G(d,p) level of theory. For this purpose, a comparative investigation was carried out by modeling hydrogen abstraction from thiols (kHA) and addition reaction to monomers (ki), which is considered a side reaction. It was confirmed that the 2,2-dimethoxy-2-phenylacetophenone (DMPA) initiator is a suitable thiol-ene initiator except for the polymerization of electron-deficient or conjugated monomers. It was determined that the azobisisobutyronitrile (AIBN) initiator could not give a homogeneous thiol-ene product regardless of the monomer structure. However, it has been found that aromatic thiols should be used to obtain relatively better results with this initiator.

Keywords

• Thiol-ene polymerization
• density functional theory
• reaction kinetics
• structure-reactivity relationships

Supporting Institution

THE SCIENTIFIC AND TECHNOLOGICAL RESEARCH COUNCIL OF TURKEY

Project Number

217Z073

Thanks

I. Degirmenci is thankful to the Scientific and Technological Research Council of Turkey (TUBITAK, Project Number: 217Z073) for funding and usage of computing resources.

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