English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Nanostructured thermosets may be obtained by self-assembly of amphiphilicblock copolymers in a reactive solvent and fixation of the morphologies by thecross-linking reaction. Nanostructuration requires the presence of a bock thatremains miscible in the polymer during polymerization. The selection of themiscible block depends on the particular system and in some cases (e.g., forepoxy-amine network based on diglycidyl ether of bisphenol A, and 4,4'-diaminodiphenylsulfone) it is very difficult to find such a block. In thismanuscript it is shown that random copolymers of methyl methacrylate (MMA) andN,N-dimethylacrylamide (DMA) containing different molar fractions of DMA, canbe used as a miscible block for the nanostructuration of epoxies. Themiscibility of the random copolymer during formation of the epoxy network wasfirst analyzed determining cloud-point conversions as a function of the molarfraction of DMA in the copolymer. A thermodynamic model of the phase separationwas performed using the Flory-Huggins model and taking the polydispersities ofboth polymers into account. A single expression of the interaction parameterbased on the theory of random copolymers provided a reasonable fitting of theexperimental cloud-point curves. The significant increase in the miscibilityproduced by using small DMA molar fractions in the copolymer was explained bythe high negative value of the binary interaction energy between DMA and theepoxy-amine solvent, associated to the positive value of the interaction energybetween DMA and MMA units. Block copolymers with poly(n-butyl acrylate) as theimmiscible block and the random copolymer P(MMA-co-DMA) as the miscible blockwere used for the nanostructuration of epoxy networks. The necessary molarfraction of DMA in the miscible block to stabilize a dispersion of nanosizedomains depended on the fraction of the immiscible block.

Nanostructured epoxies based on the self-assembly of block copolymers: a new miscible block that can be tailored to different epoxy formulations