Morphology And Properties Of Ultra-Fin Full-Vulcanized Rubber Powder/Rubber Blends

In this work, a novel ultra-fine full-vulcanized rubber powder (UFPR) including ultra-fine full-vulcanized acrylonitrile butadiene rubber(UFPNBR),ultra-fine full-vulcanized silicon rubber (UFPSiR) and rubber including epichlorohydrin rubber(ECO) and hydrogenated acrylonitrile butadiene rubber(HNBR) blends were prepared by melt blending. The morphology, dynamic, static and aging properties of this kind novle rubber blends were investigated and compared with those of conventional rubber blends.The main results are listed as following: (1) In the UFPNBR/ECO composites, TEM observations showed that ECO was tending to be continuous phase with UFPNBR as dispersion phase in UFPNBR/ECO system, whereas in NBR/ECO system ECO was tending to be dispersion phase with NBR as continuous phase. Dynamic property illustrated by DMTA demonstrated that UFPNBR/ECO had good compatibility. The mechanical properties results indicated that compression set of the blends could be decreased with adding appropriate amount of UFPNBR. To compare with NBR/ECO system, the UFPNBR/ECO had low friability temperature and good aging resistance but the mechanical properties were slightly worse than that of NBR/ECO.(2)In the UFPSiR/ECO composites, SEM observations showed that the dispersed phase UFPSiR was prone to congregate, and the particle size of dispersed phase was about several microns. Dynamic property illustrated by DMTA demonstrated that two glass transition temperatures was observed. The results of DSC showed further that UFPSiR and ECO had low compatibility, and the movement of polymer chains of UFPSiR was confined by the polymer chains of ECO. The mechanical properties results indicated UFPSiR/ECO composites had no obvious difference with SiR/ECO, but with lower compression set to SiR/ECO.(3)In the UFPNBR/HNBR composites, TEM observations showed that HNBR was tending to be continuous phase with UFPNBR as dispersion phase in UFPNBR/HNBR system, whereas in NBR/HNBR system HNBR was tending to be bi-continuous phase. Dynamic property illustrated by DMTA demonstrated that the two kinds of blends had good compatibility. The mechanical properties results indicated that the compression set of the UFPNBR/HNBR blends could be decreased with adding UFPNBR. To compare with NBR/HNBR system, the UFPNBR/HNBR had low friability temperature and good aging resistance but the mechanical properties were slightly worse than that of NBR/HNBR.