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 CC 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.