Nanostructured Epoxies Based on the Self-Assembly of Block Copolymers: A New Miscible Block That Can Be Tailored to Different Epoxy Formulations

TLDR: In this article, it was shown that random copolymers of methyl methacrylate (MMA) and N,N-dimethylacrylamide (DMA) containing different molar fractions of DMA can be used as a miscible block for the nanostructuration of epoxies, a fact that is particularly illustrated for a DGEBA−DDS epoxy network.

Abstract: Nanostructured thermosets may be obtained by the self-assembly of amphiphilic block copolymers (BCP) in a reactive solvent and fixation of the resulting morphologies by the cross-linking reaction. Nanostructuration requires the presence of a block that remains miscible in the thermosetting polymer during polymerization. The selection of the miscible block depends on the particular system, and in some cases (e.g., for epoxy−amine network based on diglycidyl ether of bisphenol A, DGEBA, and 4,4‘-diaminodiphenyl sulfone, DDS) it is very difficult to find such a block. In this paper it is shown that random copolymers of methyl methacrylate (MMA) and N,N-dimethylacrylamide (DMA) containing different molar fractions of DMA can be used as a miscible block for the nanostructuration of epoxies, a fact that is particularly illustrated for a DGEBA−DDS epoxy network. The miscibility of the random copolymer during formation of the epoxy network was first analyzed determining cloud-point conversions as a function of th...