The Effects of Carbon–Silica Dual-Phase Filler on the Crosslink Structure of Natural Rubber

Abstract

Carbon–silica dual-phase filler (CSDPF)/natural rubber (NR) vulcanizate was prepared by mechanical blending, followed by a hot-press vulcanization. The dispersion of CSDPF in the NR matrix and the effects of CSDPF on the filler–rubber interaction and structure of the rubber network were studied. Scanning electron microscope results showed that CSDPF dispersed uniformly; however, there were some aggregates of CSDPF when loading too many fillers. With an increase in CSDPF, the interaction between CSDPF and NR chains increases, which was detected by bound rubber in the CSDPF/NR compound. The spectra of solid-state nuclear magnetic resonance revealed that CSDPF could promote the formation of poly-sulfidic crosslink in the rubber vulcanization network. Further, the molecular chain movement ability of vulcanizates decreases according to the spin–spin relaxation of 1H nuclei in CSDPF/NR compounds. The crosslink density of vulcanizate increases, while the chemical crosslink and physical crosslink in the vulcanization network also increase according to the tube model.

Preparation of Poly(acrylic acid-co-acrylamide)-Grafted Deproteinized Natural Rubber and Its Effect on the Properties of Natural Rubber/Silica Composites

“…The morphology of the silica-filled composites was examined by scanning electron microscope (SEM) using an FEI Quanta 450 (Philips, Hillsboro, OR, USA). The rectangular rubber sheets (3.0 cm × 1.0 cm × 0.2 cm), after vulcanization, were frozen in liquid nitrogen and broken to investigate the dispersion of the silica in the natural rubber matrix [ 29 ]. The cross-section of samples was observed by SEM, and the dispersion of the silica was studied by energy dispersive spectroscopy coupled with SEM (SEM/EDS).…”

Review: Natural rubber – Improvement of properties

“…[ 64 ] Thorough investigation by NMR reveal that CSDPF reduce rubber chain mobility, increase crosslinking density, and promote the formation of polysulfide bonds in rubber. [ 65 ] However, modified CSDPF may facilitate the formation of more monosulfide bonds in network. [ 66 ]…”

“…[64] Thorough investigation by NMR reveal that CSDPF reduce rubber chain mobility, increase crosslinking density, and promote the formation of polysulfide bonds in rubber. [65] However, modified CSDPF may facilitate the formation of more monosulfide bonds in network. [66] Owing to two phase in one structure, CSDPF reduce filler-filler interaction, increase rubber-filler interaction that results in higher reinforcement effect in rubber, particularly in tire compounds: higher tear and abrasion resistance, improved rolling and wet skid resistance at the almost same tensile strength and elongation at break in comparison with compound containing only CB.…”

Synergistic effects of silane‐modified carbon black and nano‐silica hybrid fillers on the performance of natural rubber compounds

“…The use of CB in combination with silica has been widely studied and previously reported. [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31] Based on the authors' best knowledge, the use of silane-modified-CB resulting from covalent bond formation between commercial CB and a silane coupling agent has not been considered and reported. Authors already reported the surface modification of commercial CB by a silane coupling agent.…”