Investigation of Cure Reaction, Rheology, Volume Shrinkage and Thermomechanical Properties of Nano-TiO₂ Filled Epoxy/DDS Composites

Abstract

The cure reaction, rheology, volume shrinkage, and thermomechanical behavior of epoxy-TiO 2 nanocomposites based on diglycidyl ether of bisphenol A cured with 4,4 -diaminodiphenylsulfone have been investigated. The FTIR results show that, at the initial curing stage, TiO 2 acts as a catalyst and facilitates the curing. The catalytic effect of TiO 2 was further confirmed by the decrease in maximum exothermal peak temperature (DSC results); however, it was also found that the addition of TiO 2 decreases the overall degree of cure, as evidenced by lower total heat of reaction of the cured composites compared to neat epoxy. The importance of cure rheology in the microstructure formation during curing was explored by using rheometry. From the PVT studies, it was found that TiO 2 decreases the volume shrinkage behavior of the epoxy matrix. The mechanical properties of the cured epoxy composites, such as tensile strength, tensile modulus, flexural strength, flexural modulus, impact strength, and fracture toughness of the polymer composites, were examined. The nanocomposites exhibited good improvement in dimensional, thermal, and mechanical properties with respect to neat cross-linked epoxy system. FESEM micrographs of fractured surfaces were examined to understand the toughening mechanism.

Development of Epoxy‐Polyester Composite with Improved Thermophysical Properties for Restoration of Details of Sea and River Transport

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The Corrosion Protection Performance of the Polyurethane Coatings Containing Surface Modified Fe2O3Nanoparticles

“…Agglomerated nanoparticles can act as a defect within the coating, reducing the corrosion protection properties of the polymeric matrix. [7][8] Surface modification of the nanoparticles can reduce their surface energy and increase the interaction between the nanoparticles and the polymer matrix, preventing detrimental agglomeration. Among the different techniques for surface modification of nanoparticles, surface functionalization by organosilanes is the most commonly used method.…”

Remarkable enhancement of thermal stability of epoxy resin through the incorporation of mesoporous silica micro-filler

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