Synthesis and photoinitiated cationic polymerization of monomers with the silsesquioxane core

Abstract

A synthetic scheme was developed to prepare cationically polymerizable octafunctional monomers with silsesquioxane (TJ cores. Epoxy and 1-propenoxy functional groups were attached to the core by the hydrosilation of T~with an appropriate precursor. The steric constraintsand the requirementsfor the hydrosilationreaction are discussed.The monomers were fully characterized and then polymerized by exposure to ultraviolet irradiation in the presence of onium salt photoinitiators. The polymerization conditions for the monomers were optimized and compared with each other using real-time infrared spectroscopy. Thermal analysis was also performed on the resulting crosdinked polymers.

Thermal and Lithographic Performance of Silsesquioxane with Cycloaliphatic Epoxy‐Siloxane Hybrid Spacer for Soft Lithography

“…Of note is that thermal degradation improved at higher spacer chain length in terms of onset degradation temperature as well as the residual ceramic yield. The thermal degradation found here display almost similar behavior as found from the work of Crivello and Malik [14] whose 5% degradation occurring at about 290 °C. The degradation range at 480-550 °C is attributable to siloxane linear structure which undergoes depolymerisation and decomposition in the form of cyclic oligomers.…”

“…The effect of steric hindrance of the bulky cycloaliphatic epoxy ring to the incorporation into www.advancedsciencenews.com www.mme-journal.de the silsesquioxane structure seems insignificant due to the less congested linear chain polysiloxane spacer. [14] Viscosities of EPSQ-1, EPSQ-2, and EPSQ-3 were determined as 5.5, 6.4, and 9.2 Pa s −1 suggesting that the increase in spacer chain length enhance the viscosity. The crystallographic properties of EPSQ were studied by WAXD as shown in Figure 3.…”

Solution‐Processed, Photo‐Patternable Fluorinated Sol–Gel Hybrid Materials as a Bio‐Fluidic Barrier for Flexible Electronic Systems

“…Using these results, the degree of FEH polymerization is confirmed by the calculation of epoxy conversion degree (ECD). [30] Detailed calculation of ECD is included in the Experimental Section. The ECD value is 93.89%, which indicates successful polymerization of FEH by UV curing.…”

Transparent Omniphobic Coating with Glass‐Like Wear Resistance and Polymer‐Like Bendability

“…Although there have been publications on the crosslinking of GPOSS, the mechanical properties of crosslinked neat GPOSS have not been reported. Previous work on GPOSS and other functional POSS compounds has focused on their use as nanofillers to enhance the rigidity, wear resistance, glass transition temperature, anti‐oxidation properties, and flammability resistance of polymers …”