Synthesis of calcium silicate hydrate/polymer complexes: Part II. Cationic polymers and complex formation with different polymers

Abstract

Some high molecular weight cationic polymers, poly(diallyldimethylammonium chloride) (PDC) and poly(4-vinylbenzyltrimethylammonium chloride) (PVC), have been incorporated into the calcium silicate hydrate (C–S–H) structure during precipitation of quasicrystalline C–S–H from aqueous solution. Expansion of the interlayer spacing [0.9 nm (PDC), 1.5 nm (PVC)] and a high-carbon content provided evidence that these polymers were intercalated between layers of C–S–H when Ca/Si <1.0. Intercalation characteristic properties strongly depended on both of the type of polymer and Ca/Si ratio in C–S–H. Poly(4-vinyl-1-methylpyridinium bromide) and methyl glycol chitosan (iodide) also interacted with C–S–H, probably by surface adsorption. The C–S–H/polymer complexes were examined by Fourier transform infrared spectroscopy, ²⁹Si nuclear magnetic resonance magic angle spinning, and ¹³C cross-polarization, magic angle spinning nuclear magnetic resonance spectroscopy. Mechanisms of intercalation of different kinds of polymers between the C–S–H layers are discussed.