Application of sulfonamide derivative of calixarene for improvement of mechanical properties and thermal stability of polyurethane composite

Abstract

A calixarene derivative, 5,11,17,23-tetrakis (hydroxyl ethyl sulfonamide) calix [4]arene, was synthesized through a linear reaction from parent calix [4]arene. This sulfonamide calixarene derivative was used as a precursor to produce calixarene-polyurethane composite. Structural properties of calixarene-based synthesized precursors were studied using spectroscopic techniques such as 1 H-NMR, 13 C-NMR, and IR. Also, mechanical properties of produced polyurethane composite such as fracture elongation, modulus, and tensile strength were studied which indicated that these properties were deeply dependent upon calixarene ratio in composite. An increase in calixarene ratio resulted in a decrease the fracture elongation. In contrast, an increase in calixarene ratio caused a considerable decrease of modulus and tensile strength. The modulus and tensile strength were increased by 16.98 and 20 % as the calixarene/polyol ratio reached 3 %. Finally, TGA and DSC studies showed that calixarene ratio considerably enhanced the thermal stability of polyurethane.

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

“…When calixarene are used as cross‐linking agents in PU chains, the resulted composites show improved mechanical properties because of forming strong hydrogen bonds among the chains. Since produced composites have the same functional groups compared to those formed of calixarene having 4 hydroxyl groups, the major IR peaks of calixarene derivatives and composites are almost the same.…”

“…Taghvaei et al have studied the similar composites containing sulfonamide calixarene derivatives, such as 5,11,17,23‐tetrakis (hydroxyl ethyl sulfonamide) calix[4]arene, with PU containing different ratios of calixarene . They have found that the calixarene decreases the fracture elongation while it causes a considerable increase of modulus and tensile strength …”

“…The PU‐calixarene composite ability to separate alkaline metal cations has been studied . Calixarene based synthesis of PU and enhancement pf mechanical and structural properties of PU have been widely reported at literature . Zheng et al have used calix[4]arene as chain extender at PU preparation .…”

“…Generally, calixarenes have played an important role as complexing agent to improve the stability, elasticity, and thermal properties of polymers and the role of amide groups and macro cycles in mentioned properties have been studied . The improvement of PU mechanical properties has been studied through formation of its composite with different ratios of calix[4]arene derivative . In this work, a calixarene derivative, 5,11,17,23‐tetrakis (hydroxyl ethyl sulfonamide) calix[4]arene, was synthesized through a linear reaction from parent calix[4]arene used as precursor to produce PU‐calixarene composite.…”

“…In this work, a calixarene derivative, 5,11,17,23‐tetrakis (hydroxyl ethyl sulfonamide) calix[4]arene, was synthesized through a linear reaction from parent calix[4]arene used as precursor to produce PU‐calixarene composite. If the monoethanol amine used in this work is replaced with diethanol amine after the chlorosulfonation of calixarene, the effect of produced calixarene would be remarkably different regarding 8 hydroxyl groups instead of 4 hydroxyl groups …”