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CPP: Fachverband Chemische Physik und Polymerphysik

CPP 24: Poster Session I

CPP 24.42: Poster

Montag, 16. März 2020, 17:30–19:30, P3

Studies on the Effect of Stoichiometric Changes on Thermomechanical Properties of Anhydride-cured Epoxy Resin — •Farnaz Emamverdi — BAM, Berlin, Germany

Introducing boehmite nanoparticles (BNPs) to anhydride-cured epoxy networks can improve the mechanical properties of the polymer. Understanding of the interaction between BNPs and the epoxy system is crucial since previous studies reveal that the interaction between the BNPs and the epoxy induces changes in the curing reaction locally. AFM-based studies revealed that the anhydride molecule has a preferential interaction with the BNP. It is hypothesized that such preferential absorption disturbs the curing reaction and causes a stoichiometric imbalance at the interphase in the epoxy matrix. To explain this behavior, we prepared off-stoichiometric samples where ratio between epoxy and anhydride were systematically altered. Previous studies have failed to focus on stoichiometric changes of epoxy-anhydride system. The effect of stoichiometric imbalance on the thermomechanical properties like the shear modulus and Tg is the focus of this study. The characterization for rich-hardener, poor-hardener and standard samples were done by FT-IR, TGA, DMA and DSC. Brown discoloration occurred is poor hardener sample. TGA results showed that all samples are thermally stable up to 200°C where the poor-hardener sample is the most stable one. DMA measurements show a post-curing effect for all samples, which is most pronounced in rich-hardener sample where G* dropped by 28%. Poor-hardener sample shows the highest Tg and crosslinking density.