Synthesis and Characterization of Functionalized Calix[4]arene Derivatives and Preparation of Rigid Polyurethane Foams by the Incorporation of Calixarene

Calix[4] arenes namely, 5,11,17,23 tetra tert butyl calix[4] arene and 5,11,17,23 tetra chlorosulfonyl calix[4] arene were synthesized to produce octakis (hydroxyl ethyl) sulfonamide calix[4] arene which was used in polyurethanecalixarene rigid foam composite formulation. The effect of calixarene ratio on mechanical properties of synthesized composites was studied at three calixarene ratios including 1.5, 2, and 3 % (w/w). The obtained data indicate that the tensile strength and modulus are increased as the calixarene ratio increases while the fracture strain is decreased. Quantitatively, addition of 3% (w/w) of calixarene to the polyurethane resulted in 30.99% and 30.01% improvements in modulus and tensile strength, respectively. Contrarily, a decrease of about 13.1% was observed in fracture strain when compared to the properties of the pristine polyurethane rigid foam. The effect of Calixarene on thermal stability of Calixarene-polyurethane composite indicating that Calixarene component strictly enhances the thermal stability of composite.