Surfactant bilayer adsorption and MPS admicellar polymerization on natural rubber latex particles

Abstract

The adsorption isotherms of four surfactants (CPC, DBSA, C7BzO and NP30) were considered. From the results revealed that the adsorption isotherms of CPC, DBSA and C7BzO presented the forming of bilayer adsorption which appropriated to use in admicellar polymerization while NP30 revealed the forming of monolayer adsorption for all NR content. Moreover the substrate content, the surfactant chain length, the head group size and the pH of solution affected the amount of surfactant adsorption on the NR particles. The polymethacryloxypropyltrimethoxysilane coated on NR particles at 5 %w/v of NR via admicellar polymerization using CPC and DBSA as a reaction template were characterized by particle size analyzer, FT-IR, TGA, FE-SEM, EDX and TEM. The results from particle size analyzer revealed that the size of PMPS-ad-NR was increased with MPS content. FT-IR spectrum of PMPS-ad-NR exposed the combination of characteristic peaks of NR and PMPS. Furthermore, the peak intensities disposed to be stronger when the MPS concentration increased. The PMPS-ad-NR decomposition curves presented the single transition like one single component of NR. When PMPS content was increased, the tail of the transition was shifted to end at higher temperature together with significant residue content. From FE-SEM and EDX, the synthesized products demonstrated the full coverage of PMPS over NR particles and exhibited the uniform dispersion of Si all over the samples. From TEM exposed that the core NR was fully coated by PMPS.