Synthesis Of CMC Graft Copolymer And Its Application In Cement-Base Materials

CMC is a product of biological degradation, no-toxicity, salt-resistance, regeneration and inexpensive. As for the modification of CMC graft copolymerization, it can be endowed with some new properties while virtues while CMC inhered with can not be destroyed. The application of grafting copolymer of CMC mainly focus on the field of oil-drilling, mineral engineering, textile industry, paper industry, paint and coatings industry, daily-use chemical products and so on, however the relevant research and utility on the realm of cement-base material is rarely. Presently, CMC is used as thickening agent and water-retaining agent in the cement-base material separately. While we synthesized a copolymer emulsion, used CMC, methyl methacrylate as the substrate and monomer of graft copolymerization respectively, then was utilized in plant fibres reinforced cement-base composites. It demonstrated that when the dosage of the graft copolymer is1%, the composites obtain the better physical properties, such as flexural strength, bending modulus, and durability. But when the copolymer was used in cement mortar or concrete, the effect of modification is not ideal. Consequently, this paper used CMC as the substrate, water and KPS as solvent, initiating system respectively, styrenesulfonate and methacrylate as monomer, to synthesis a kind of ternary-graft-copolymer emulsion, extract the pure graft copolymer from the emulsion for structure characterization, which was used FTIR, XRD, SEM, and TG-DSC. And the copolymer emulsion was applied in cement-base material as modifier to research the effect about the flexural strength and compressive strength of cement-base material mixture with the copolymer, the best polymer-cement ratio is1.5%, analysis the modification mechanism by means of observe the micro morphology of the cement-base material with the aid of XRD, SEM.