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This rapid communication reports the first successful clarification of the difference in the crosslink inhomogeneity at the nanometer scale for two types of structurally identical epoxy resins cured with a phenolic hardener under organophosphine catalysts.

Under hygrothermal conditions, the glass transition temperature of an amine-cured epoxy resin decreased over time. This decrease originated from a progressive reduction in the cross-linking density rather than from the plasticization effect of sorbed water. Degradation reactions involving scission of ether bonds occurred, producing bisphenol A and its derivatives. This bond scission was initiated by radical-mediated thermal decomposition, followed by hydrogen donation from sorbed water.

The enantiopurity of chiral compounds is key in determining their activity or therapeutic action. Here, the authors present a versatile NMR method of enantiomeric excess determination using a symmetrical achiral molecule as resolving agent, based on complexation with analyte, without formation of diastereomers.

Epoxy resins, which are obtained by the curing reaction of epoxy- and amine-compounds mixture, have been often utilized in contact with metals. We herein report on the chemical composition of the epoxy resin in close proximity to the copper interface on the basis of a non-destructive method. The concentration of the amine component in the interfacial region was 2-fold higher than that in the bulk, and the interfacial enrichment extended over at least 10 nm.

A combination of AFM-based AM-FM and nDMA methods evidences the effect of the curing temperature on the structural heterogeneities in epoxy networks: a lower pre-curing temperature provides a less heterogeneous network, which in turn can control the thermal and mechanical properties of resultant epoxy resins.

The segmental mobility of polymers at the interface contacted with air, a liquid and a solid is much different from that in the internal bulk phase. This review summarizes the recent studies offering a concept that the polymer interface is a useful medium for functionalization of solid polymer materials.

The cross-linking structure and physical properties of epoxy resins cured with amine under off-stoichiometric ratio conditions were examined. As the excess amine increased, some of the amine not only remained as unreacted monomers or low-molecular-weight isolated chains within the cross-linking structure, but also formed dangling chain ends. As a result, the cross-linking density and mass density decreased, as did the glass transition temperature. On the other hand, Young’s modulus increased with the excess amount of amine due to the suppression of the widening distance between phenyl groups.