Preparation, characterization and application of polymeric diols with comb-branched structure and their nanocomposites containing montmorillonites

The polymeric diols with comb-branched structure (CPD) and their nanocomposites containing montmorillonites (MMT) were prepared through three-step reaction on basis of molecular design. The effect of experimental parameters, such as molar mass of oligomer polyols, catalysts and MMT on conversion of –NCO group during polymerization was investigated by utilizing FTIR to measure content of –NCO group varied as reaction time. In addition, the structure of comb-branched polymeric diols was characterized by FTIR and 1H NMR. The results show that the comb-branched chains contain reactive Cdouble bond; length as m-dashC double bonds in CPD. The nature of dispersion of montmorillonites in CPD was characterized by X-ray diffraction. The results show that Na+-MMT is exfoliated and organo-MMT is intercalated in CPD via in-situ polymerization. Finally, the properties of water-borne polyurethane modified with CPD or CPD/2T-MMT nanocomposite were compared with those of common water-borne polyurethane, and the comb-branched chains and 2T-MMT improve the properties of water-borne polyurethane.