Synthesis and characterization of silica nanocomposite in situ photopolymerization

Abstract

This study was carried out on nanocomposites consisting of nanometer silica fillers embedded in thermoset polymers that were prepared via the in situ polymerization of ultraviolet (UV) curable systems containing different contents of nanometer silicas by irradiation of UV light. Because of the introduction of nanosilicas, the curing rates of the UV curing of dispersing systems were played down; that is, the curing times were prolonged, but the mechanical properties of the nanocomposites, such as tensile strength and Young's modulus, increased, and the thermostability of the nanocomposites at temperatures lower than 400 K improved. The dispersing states of nanometer silicas within the polymer matrix were characterized by transmission electron microscopy, and the results show that the nanometer silicas had good homogeneously dispersing states within nanocomposites containing less than 3 wt % nanometer silicas.

Synthetic clay nanocomposite‐based coatings prepared by UV‐cure photopolymerization

“…16 As an alternative to the procedures described above, the preparation of nanocomposites using UV-curing technology has only recently been reported. 12,17,18 Uhl et al 17 demonstrated that the presence of clay reduced the cure time of urethane/acrylate-based films. More-over, Decker et al 12 synthesized highly resistant nanocomposites based on polyurethane-acrylate systems using high solvent-free UV cure and pretreatment of the clay through surface alkylammonium cation exchange to render it more organophilic.…”

Preparation and characterization of UV‐curable MPS‐modified silica nanocomposite coats

“…Muh et al 7 first synthesized UV-curable hybrid nanocomposite through a sol-gel process of alkoxysilane-containing bismethacrylate-based monomers. Xu et al 19 introduced nanosilica fillers into biphenyl A epoxy acrylate directly and successfully prepared corresponding nanocomposites with improved thermal stability and mechanical properties. However, all these UV-curable nanocomposites contained reactive dilutes (e.g., TMPTA, HDDA) or oligomers (e.g., epoxy acrylate, urethane acrylate) or both of them in UV-curable formulation.…”

A kinetics study on thein situreversible addition–fragmentation chain transfer and free radical polymerization of styrene in presence of silica aerogel nanoporous particles

“…However, some researchers reported that silica nanoparticles slow down the polymerization rate because they absorb UV radiation in UV-curing systems. [22] In other studies, silica nanoparticles have resulted in an increase the rate of polymerization which has been attributed to changes in propagation and termination rate constants. [23][24][25] Also, modified nanoparticles as multifunctional sites form a three-dimensional network which leads to reduction in the mobility of chains and thus slow down the rate of polymerization.…”