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ABSTRACT Epoxidized natural rubbers (ENRs) were prepared. ENRs with different concentrations of up to 20 wt % were used as modifiers for epoxy resin. The epoxy monomer was cured with nadic methyl anhydride as a hardener in the presence of N,N-dimethyl benzyl amine as an accelerator. The addition of ENR to an anhydride hardener/epoxy monomer mixture gave rise to the formation of a phase-separated structure consisting of rubber domains dispersed in the epoxy-rich phase. The particle size increased with increasing ENR content. The phase separation was investigated by scanning electron microscopy and dynamic mechanical analysis. The viscoelastic behavior of the liquid-rubber-modified epoxy resin was also evaluated with dynamic mechanical analysis. The storage moduli, loss moduli, and tan δ values were determined for the blends of the epoxy resin with ENR. The effect of the addition of rubber on the glass-transition temperature of the epoxy matrix was followed. The thermal stability of the ENR-modified epoxy resin was studied with thermogravimetric analysis. Parameters such as the onset of degradation, maximum degradation temperature, and final degradation were not affected by the addition of ENR. The mechanical properties of the liquid-natural-rubber-modified epoxy resin were measured in terms of the fracture toughness and impact strength. The maximum impact strength and fracture toughness were observed with 10 wt % ENR modified epoxy blends. Various toughening mechanisms responsible for the enhancement in toughness of the diglycidyl ether of the bisphenol A/ENR blends were investigated. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39906. [ABSTRACT FROM AUTHOR]

Cage ‐ structured polyhedral oligomeric silsesquioxane (POSS) molecules were used as modifiers in the fabrication of poly(vinyl alcohol) (PVA) membrane for the separation of an azeotropic mixture of tetrahydrofuran (THF) and water system. Poly(ethylene glycol) and anionic octa(tetramethyl ammonium)‐functionalized POSS were used for this study. The membranes exhibited excellent water selectivity and permeance because of their preferential interactions toward water molecules in the azeotropic THF–water mixture. In the presence of poly(ethylene glycol)–POSS and anionic octa(tetramethyl ammonium)–POSS, the PVA membrane exhibited a significant increase in selectivity. A modified Maxwell–Stefan equation was used for the computation of the theoretical flux, which was compared with the experimental values. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47060. Poly(vinyl alcohol) (PVA) containing cage structured polyhedral oligomeric silsesquioxane (POSS) molecules as modifier to fabricate a membrane for the separation of azeotropic mixture of tetrahydrofuran (THF) ‐ water system. Polyethylene glycol (PEG) and anionic‐octa(tetramethylammonium) (Octa‐TMA) functionalized polyhedral oligomeric silsesquioxane (POSS) were employed for the present study. The membranes exhibited excellent water selectivity and permeance due to the preferential interaction of membrane towards water molecule in the azeotropic THF‐ water mixture. In the presence of PEG‐POSS and Octa‐TMA‐POSS, PVA membrane exhibited a significant increase in selectivity. Modified Maxwell‐ Stefan equation was used for the computation of theoretical flux and was compared with the experimental values. [ABSTRACT FROM AUTHOR]