SEM micrographs of the WSNR vulcanizates with PEO
loadings at 20 and 40 phr before and after immersion in
water for 14 days are presented in Fig. 5. The white solid
materials that could be SAP, SAPC, or PEO are clearly observed
as particulates and agglomerates before immersing
in water (Fig. 5a and b), but after immersion in water for
14 days, a large number of holes were seen while the white
particulates or agglomerates had disappeared or being
eroded (Fig. 5c and d), i.e., clear differences in morphologies
of the vulcanizates are observed in Fig. 5a and c and
b and d, respectively.