Polyurethane Rigid Foams Reinforced by Doubly Modified Nanosilica

Abstract

Nanosilica was modified by γ-glycidoxypropyltrimethoxysilane and further modification was accomplished by diethanol amine. The modified nanosilica was used in polyurethane rigid foam formulations. Formulated polyurethane rigid foams were characterized by Fourier transform infrared Spectroscopy and thermal analysis methods. Tensile test, dynamic mechanical analysis, thermomechanical analysis, and scanning electron microscopy were performed for the evaluation of mechanical, thermomechanical, and morphological properties. The modified nanosilica enhanced thermal stability and static mechanical properties, and reactive functional groups on the nanosilica surface affected reactant ratios by causing decrements in hard segments, which were accomplished by reduced storage modulus (E’).