Synthesis of Functionalized Hyperbranched Polymers via Catalytic Chain Transfer Polymerization and Thiol-ene Click Chemistry

摘要

Hyperbranched polymers are widely used in diverse applications. It was found that stimuli responsive hyperbranched polymers can be used to deliver low molecular weight compounds to hair over a large period of time [1]. Many formulations containing low or high molecular weight compounds with silicon functionalities are known for various personal care applications in [2, 3]. It was shown that using a specific concentration of a cobalt oxime boron fluoride (COBF) chain transfer catalyst in the Catalytic Chain Transfer Polymerization (CCTP) of ethylene glycol dimethacrylate ( EGDMA) results in hyperbranched polymers via the cascade trimerization of the monomer [4]. It controls the competition between monomer insertion and chain transfer. Using a lower concentration of COBF, however results in crosslinked polymers because at low levels COBF fails to inhibit cross-linking of the vinyl groups [5]. CCTP does not only give polymers of highly interesting architecture, it is also an excellent tool for the synthesis of vinyl terminated low molecular weight polymers [6, 7]. These double bonds provide the potential for further reactions [8] and therefore allow for the synthesis of a wide range of functionalized polymers in a very straightforward way from few basic starting materials.