Tack Properties of Nanostructured Epoxy-Amine Resins on Plasma-Treated Glass Substrates.

A probe tack test, coupled with in situ imaging, was used to evaluate the influence of an air plasma treatment on glass substrates on the fracture energy of nanostructured epoxy-amine resins. Nanostructuration was achieved by the addition of thermoplastic triblock copolymers. The influence of the surface treatment was assessed by splitting the fracture energy (tack energy) into three main contributions (cavitation, viscous flow, and stretch). We showed that before gelation, the interfacial strength depended on the nature of the copolymers and on their interaction with grafted functions (R-COOH and R-C=O) by air plasma treatment. The latter also influenced the cohesion of the resins, impacting the copolymers' phase separation and, as a consequence, conversion rate. The tack test, coupled with rheology and thermal (differential scanning calorimetry) measurements, was relevant to explain how the balance of interactions contributed to the fracture energy up to the gel point.

Parameters Influencing Moisture Diffusion in Epoxy-Based Materials during Hygrothermal Ageing-A Review by Statistical Analysis.

The hygrothermal ageing of epoxy resins and epoxy matrix composite materials has been studied many times in the literature. Models have been developed to represent the diffusion behaviour of the materials. For reversible diffusions, Fick, Dual-Fick and Carter and Kibler models are widely used. Many parameters, correlated or not, have been identified. The objectives of this review by statistical analysis are to confirm or infirm these correlations, to highlight other correlations if they exist, and to establish which are the most important to study. This study focuses on the parameters of the Fick, Dual-Fick and Carter and Kibler models. For this purpose, statistical analyses are performed on data extracted and calculated from individuals described in the literature. Box plot and PCA analyses were chosen. Differences are then noticeable according to the different qualitative parameters chosen in the study. Moreover, correlations, already observed in the literature for quantitative variables, are confirmed. On the other hand, differences appear which may suggest that the models used are inappropriate for certain materials.