Synthesis of a liquid zirconium hybrid resin and the ability of the resin to accelerate the curing of a transparent silicone-modified cycloaliphatic epoxy nanocomposite

摘要

A liquid zirconium hybrid resin (Zr-QR) was synthesized through sol-gel reactions of zirconium butoxide with silanol-terminated polydimethylsiloxane (DMS-S12) and -glycidoxypropyltrimethoxysilane (Z-6040). The sol-gel reactions were monitored using Fourier transform infrared (FTIR) spectroscopy and proton nuclear magnetic resonance spectroscopy. The Zr-QR morphology was investigated using field emission transmission electron microscopy. The Zr-QR had a well-ordered morphology and the dimensions were less than 5 nm. These properties were achieved because DMS-S12 was used to separate the zirconium clusters and Z-6040 was used to stabilize the Zr-QR. The acceleration of the curing reaction between silicone-modified cycloaliphatic epoxy (SEP) and methylhexahydrophthalic anhydride (MHHPA) caused by the Zr-QR was investigated. Differential scanning calorimetry and FTIR spectroscopy investigations showed that the Zr-QR first reacted with MHHPA, producing chelating ligands and carboxylic acid. Unlike in the conventional method (adding acetic acid to cause non-reactive chelating ligands to form), the carboxylic acid produced effectively accelerated the curing reaction between the SEP and MHHPA. The chelating ligand produced from the Zr-QR and MHHPA suppressed the gelation of the Zr-QR itself during the nanocomposite (SEP-Zr-QR) curing process. The cured SEP-Zr-QR nanocomposite exhibited excellent optical transmittance at visible wavelengths.(c) 2015 Society of Chemical Industry