Excluded chain dimensions and network size in g.p.c

Attempts have been made to correlate the average network size of polystyrene, poly(methyl methacrylate), poly(methyl acrylate), poly(n-butyl acrylate) and poly(vinyl acetate) gels with the maximum size of the polymer molecule which can permeate the gels. The average size of the network structure ( r c ) was estimated from the average molecular weight between crosslinkages ( M c ) derived from the glass transition temperatures of the gels. The maximum molecular size which could permeate into the network was expressed as the root-mean-square end-to-end distance [ ( r 2 ) 1 2 ] of the permeable substance with the molecular weight at exclusion limit ( M lim) obtained by gel permeation chromatography. Both r c and ( r 2 ) 1 2 decreased with increasing total dose of γ-irradiation or increasing amount of the crosslinking agent. Linear relations were also obtained between r c and ( r 2 ) 1 2 covering a wide range of total dose and amount of the crosslinking agent.