An Amphiphilic Acrylic Copolymer/Montmorillonite Nanocomposite1

摘要

A bi-component copolymer/layered silicate nanocomposite was synthesized by way of a two-stage radical copolymerization of emulsion intercalation and solution intercalation, using acrylates, methacrylic acid and acrylamide as monomers. The water-based product was designed with a structure of a hydrophobic copolymer dispersed in an aqueous copolymer solution to meet needs of warp sizing agents on adhesiveness to hydrophobic and/or hydrophilic fibers, appropriate glass transition temperature, as well as water-solubility. XRD patterns for the product films showed an exfoliated structure of montmorillonite (MMT) in the part of soluble acrylic copolymer as the MMT content equal to or less than 7%, while in the part of emulsion copolymer alone or the product as a whole, the MMT showed an intercalated structure. Determination of DSC indicated that chemical bondings occured between the hydrophobic and hydrophilic components, which guaranteed storage stability of the system and water-solubility of the sizing film, and that there were three T_gs corresponding to the emulsion copolymer, solution copolymer and the interfacial copolymer between the two phases. All the T_gs increased with increasing content of the MMT in the composites.