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The reaction of tetrafunctional diamines and bifunctional amines with monoepoxy compounds was investigated by gel‐permeation chromatography. At a stoichiometrically equivalent ratio of the functional groups or excess of amine, the consecutive reaction of the epoxide groups with the hydrogen atoms of the amino groups is the only reaction that is taking place; if epoxide is present in excess, the OH groups formed in the reaction are gradually added to the epoxide groups. The ratio of the rate constants of the reaction of the epoxy group with the hydrogen atoms of the primary and secondary amino group was calculated from the concentrations of the reaction products at various excess amounts of amines. The ratio is in good accord with the value calculated from the gel points and limiting stoichiometric ratios in the curing of diepoxides with diamines.

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Homogeneous membranes based on fullerene-polyphenylene oxide compositions containing up to 2 wt% fullerene C 60 were prepared. The effect of fullerene addition on PPO transport properties was studied in gas separation and pervaporation processes. Permeability coefficients of H 2 , O 2 , N 2 , CH 4 , and CO 2 were measured; a correlation between gas transport properties and membrane free volume was established. Pervaporation properties were studied for the system with ethyl acetate synthesis reaction: quaternary system ethanol-acetic acid-water-ethyl acetate and some constituent binary and ternary mixtures. Pervaporation in binary systems, ethanol -water and ethyl acetate-water was considered with the use of the data on sorption capacities and interaction parameters. In pervaporation of a quaternary reacting mixture, the permeate containing essentially ethyl acetate was obtained. Results show that membranes with fullerene additives exhibit improved transport properties.

SynopsisThe effects of inert solvent concentration of crosslinking agent and initiator and polymerization temperature on specific surface area, porosity, penetration modulus, stress a t break, and inner and surface morphology of the copolymer glycidyl methacrylate-ethylene dimethacrylate were investigated. There is a direct influence of interfacial tension between the continuous and dispersed phases in suspension a t the beginning of polymerization on the morphology of the bead, and hence on the resulting physical characteristics of the structure.