Abstract
Reported herein are the systematic design and characterization of several novel polyurethane (PU) copolymers containing a macrocyclic porogen (beta-cyclodextrin; beta-CD). These copolymers were synthesized from the reaction between beta-CD with different types of diisocyanate linker molecules (e.g., 1,6-hexamethylene diisocyanate (HDI), 4,4'-dicyclohexylmethane diisocyanate (CDI), 4,4'-diphenylmethane diisocyanate (MDI), 1,4-phenylene diisocyanate (PDI) and 1,5-naphthalene diisocyanate (NDI)) at variable synthetic conditions. The copolymers were characterized using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), solid state C-13 CP-MAS NMR, H-1/C-13 solution NMR spectroscopy, thermogravimetric analysis (TGA) and elemental analyses (CHN). The PU copolymers were generally insoluble in water and the optimal preparation of copolymer materials for sorption-based applications is for beta-CD/linker synthetic mole ratios from 1:1 to 1:3. The practical upper limit of the crosslink density (similar to 1:7, beta-CD/linker) depends on the steric bulk of the cross linker units. Crown Copyright (C) 2010 Published by Elsevier Ltd. All rights reserved.