Effect of fillers on the properties of poly(ethylenevinylacetate) 1:1 blends with polychloroprene

Abstract

Effect of fillers (such as carbon black (N110), precipitated silica, and their 50.50 mixture) on 1:1 blends of poly(ethylenevinylacetate), EVAc, and polychloroprene, CR, was studied. Torque and effective occluded volume were determined from the rheometric data. Silica-filled systems showed higher relative torque, DminR, higher maximum torque rise (Dmax-Dmin), and higher in-rubber structure, ?f, compared to the carbon black-filled systems. The difference originated in higher agglomeration of silica. Corroborative evidence was also obtained from higher storage modulus leading to higher occluded volume effectiveness factor, fd. Carbon black filled compounds show higher OVEF, fy. values obtained from Young's modulus as well as higher interaction parameter, Y/r, where Y is the Young's modulus in the linear region (?= 1 to 3) and r is the ratio of storage moduli measured at 1 % and 5% double strain amplitude, DSA. The degradative effect of dicumyl peroxide, DCP, at higher doses (6 phr) lowers DminR, ?f, and fy (calculated from Young's modulus). The fd calculated from storage modulus for DCP and resol-cured compounds shows higher values compared to the uncured one. © ChemTec Publishing.