Spatial heterogeneity crosslink density

Veksli et al. have investigated the NR crosslinked networks prepared by two-stage y-irradiation of rubber latex with dilferent spatial heterogeneity. The irradiated latex emulsions (L-network) and dried latex (S-network) have dilferent crosslink density. The ESR spectra of spin probe dispersed in both L- and S-rubber networks at dilferent temperatures are shown in Figure 25.10(a) and (b). The shapes of the spectral line of the spin probed L- and S-rubber networks are dilferent at and above —23 °C, referred to the Ts mx and correlates with Tg of NR matrix. The improvement of narrow component with increase in temperature is higher for S-network in comparison... 

Pan, S.-J. Mark, J. E., Model Networks of End-Linked Polydimethylsiloxane Chains. XV. Spatially Heterogeneous Networks Containing Domains of Very High Crosslink Density. Polym. Bull. 1982, 7, 553-559. 

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