Photocurable Poly(ethylene glycol) Diacrylate Resins with Variable Silica Nanoparticle Loading

Abstract

Photocurable nanocomposites have tremendous potential in tissue engineering, advanced manufacturing, and structural, multifunctional materials. This project investigates the effect of silica (SiO 2 ) nanoparticle loading content on the thermal, mechanical, physical, and morphological characteristics of the nanocomposite. An increased concentration of SiO 2 nanoparticles causes a decrease in the gel fraction of the nanocomposite, which, at low nanoparticle loading, degrades the thermal and mechanical properties. However, further addition (>3.8 wt %) causes an increase in the glass-transition temperature, Young's modulus, and ultimate compressive strength. The addition of the nanoparticles had no significant effect on the hydrophilicity according to water uptake experiments. Small-angle X-ray scattering experiments, in conjunction with scanning electron microscopy and transmission electron microscopy, indicated a multimodal particle size distribution and the presence of largescale aggregates.

Covalently integrated silica nanoparticles in poly(ethylene glycol)-based acrylate resins: thermomechanical, swelling, and morphological behavior

“…As discussed in our previous study, the unfunctionalized SiO 2 nanoparticles cause a decrease in the gel fraction with the addition of 3.8, 7.4, and 10.7 wt%. 44 However, further addition of nanoparticles to achieve 13.8 wt% resulted in no statistically significant changes. 44 Unlike the unfunctionalized SiO 2 nanoparticles, the increasing weight fractions of V-SiO 2 and MA-SiO 2 do not cause a decrease in gel fraction.…”

“…The process to prepare silica-loaded nanocomposites was adapted from our previous protocols. 44 Composite samples were made by loading MA-SiO 2 into PEGDA. To reduce MA-SiO 2 aggregation, the nanoparticles were first dispersed in THF (0, 0.04, 0.08, 0.12, or 0.16 g of SiO 2 was added to 3 mL THF) and sonicated for 40 min.…”

“…Separately, DMPA was mixed with the PEGDA at a ratio of 0.0035 : 1 w/w (DMPA:PEGDA) based on a previous optimization study. 44 The THF solution was then pipetted into 1.0 g of the DMPA/PEGDA mixture and stirred at 23 1C for 45 min. Next, the THF was evaporated at 23 1C and the solution was transferred into a silicone mold and cured under a MelodySusie UV Gel Nail Polish Dryer UV light (Model DR-301C, wavelength (l) of B365 nm) for 3 min.…”

“…Water uptake was performed for 43 hours based on previously developed protocol. 44 An experiment to confirm the water uptake equilibrium time was conducted (see Fig. S1, ESI †).…”

“…32 Earlier work from our laboratory noted that nanocomposites containing unfunctionalized SiO 2 nanoparticles exhibited the behavior that the addition of particles caused the composite's Young's modulus and ultimate compressive stress to increase by 2Â and 3Â, respectively. 44 The high modulus SiO 2 nanoparticles stiffen the matrix around it by limiting mobility, which increases the modulus and contributes to a more robust material. Others have noted that the increase in modulus is dictated by the interfacial area, where a higher additive surface area leads to a stiffer matrix.…”