Functional poly(carbonate-co-ether) synthesis from glycidyl methacrylate/CO2 copolymerization catalyzed by Zn–Co(iii) double metal cyanide complex catalyst

Abstract

Polycarbonates with pendant functional groups have attracted much attention due to their capability for further chemical modification and post-polymerization. This work describes the synthesis of a poly(carbonate-co-ether) with massive pendant acrylate groups from the copolymerization of glycidyl methacrylate (GMA) with carbon dioxide (CO₂), using a nanolamellar zinc-cobalt double metal cyanide complex (Zn–Co(III) DMCC) catalyst. The carbonate linkage content (F_CO2) of the poly(carbonate-co-ether) could be varied from 42.2 to 68.0% by changing the polymerization conditions. Of importance, 4-methoxyphenol was applied for regulating the copolymerization. It could not only act as an inhibitor for completely depressing the self-polymerization of GMA via free radical polymerization of the double bond, but also modulate the molecular weight of the resultant copolymers. The obtained copolymer had two terminal hydroxyl groups, which were confirmed by the electrospray ionization-tandem mass spectrometry (ESI-MS) technique. A new thermoset with high glass transition temperature (T_g: 105 or 120 °C) and massive carbonate units as well as hydroxyl (or carboxylic) groups was prepared by the curing reaction of the GMA–CO₂ copolymer with allyl alcohol or acrylic acid in the presence of 2,2′-azobisisobutyronitrile (AIBN).