Surface modification of silica with a hydrophilic polymer and its influence on reinforcement of natural rubber latex

Abstract

Surface modification of precipitated silica particles was carried out in both aqueous and non aqueous media separately with a polyacrylic based hydrophilic polymer synthesized in the laboratory. FTIR spectroscopy and thermo gravimetric analysis of the modified and unmodified silica particles were performed to confirm successful surface modification. Colloidal stability of the aqueous dispersions of the unmodified/modified silica particles were observed at different pH levels. The dispersions at neutral pH were incorporated in different proportions to un-compounded and compounded natural rubber latex (NRL) separately and thin latex films were produced from them by casting. Dispersability of silica particles within the rubber matrix was examined through microstructure studies of films cast from unmodified/modified silica incorporated un-compounded NRL. The influence of surface modification upon the reinforcement of NRL was investigated through tensile and tear strength properties of vulcanized NRL cast films containing modified silica. The uniform dispersion of silica particles and the improved mechanical properties envisaged better compatibility of modified silica particles with NRL by means of interfacial interactions. A significant improvement in the mechanical properties was observed in the films produced with 5-7 phr of modified silica.

Ti3C2Tx MXene‐Reinforced Natural Rubber Nanocomposites with Tailored Mechanical and Antiaging Properties

“…In general, the addition of foreign material into NR latex affects its stability, which can be determined by Zeta potential. [ 68 ] Also, it is considered stable dispersion should have a zeta potential of below −30 mV or above +30 mV. [ 69 ] As shown in Figure a, the zeta potential of NR latex (NRMX‐0) is about −43.5 mV, which belongs to a negatively charged stable colloidal system.…”

Properties of rice husk ash silica filled natural rubber and acrylonitrile-butadiene rubber blends

“…Broadband in the range around 3800-3000 cm -1 wavenumbers can be observed and that is due to the stretching and vibration modes of hydroxyl (-OH) groups of silanol groups and adsorbed water molecules present on the silica surface (Somaratne et al, 2014;Premaratne et al, 2014). The peak at 1639 cm -1 wavenumber is due to the bending vibration mode of hydroxyl bonds in the adsorbed water molecules (Zhou et al, 2002;Somaratne et al, 2014;Premaratne et al, 2014). These features have indicated the hydrophilic nature of RHAS.…”

“…These features have indicated the hydrophilic nature of RHAS. Also, the peaks at 1085 cm -1 and 795 cm -1 wavenumbers can be attributed to the asymmetric and symmetric stretching vibration modes of the Si-O-Si bonds, respectively, while the peaks at 494 cm -1 and 465 cm -1 wavenumbers demonstrate the bending vibration of the Si-O-Si bonds (Guo et al, 2008;Somaratne et al, 2014). The stretching vibration mode of the Si-OH bond is represented by the wavenumber of 958 cm -1 .…”