Preparation and properties of organic–inorganic hybrid gel films based on polyvinylpolysilsesquioxane synthesized from trimethoxy(vinyl)silane

Abstract

Polyvinylpolysilsesquioxane (PVPS) organic-inorganic hybrid gel films comprising polyethylene and siloxane backbone linkages were prepared through two routes: trimethoxy(vinyl)silane (VTS) was first subjected to radical polymerization of the vinyl groups, followed by acid-catalyzed hydrolytic polycondensation of the trimethoxysilyl groups (route A) to afford PVPS; in the second route PVPS was prepared in reverse order (route B). PVPS gel films were transparent and homogeneous. We find that the mechanical and heat-resisting properties correlate both to the degree of polymerization and the degree of cross-linking.

Influence of symmetry/asymmetry of the nanoparticles structure on the thermal stability of polyhedral oligomeric silsesquioxane/polystyrene nanocomposites

“…Silica and layered silicates were first used for this purpose [2–5], so giving rise to composites showing improvements of mechanical and thermal properties if compared with those of conventional polymers [6–8]. The dispersion at nanoscale level of filler in polymeric matrix generally significantly improves physical, mechanical, magnetic, optical, barrier, and flammability properties in comparison with virgin polymer [9–16]. Also, it leads the pronounced increase of thermal stability [12, 16–18], it being important feature because nanocomposites so obtained can be subjected to high temperatures during processing and/or in service.…”

Radical polymerization behavior of trimethoxyvinylsilane

“…Silicon‐containing polymers are of great interest to industry for a variety of applications. Radical polymerizations of vinylsilanes have been attempted by many workers for preparation of silicon‐containing polymers 1–12. Hydrovinylsilanes, such as vinylsilane and diphenylvinylsilane, are radically polymerized to yield oligomers, in which vinyl and hydrosilylative polymerizations proceed concurrently 4–6.…”

“…Si‐trisubstituted vinylsilanes, including trialkylvinylsilanes, were reported to react only sluggishly under usual radical polymerization conditions, although they are considered to undergo vinyl polymerization 6, 9, 10. On the other hand, trimethoxyvinylsilane (TMVS) and triethoxyvinylsilane, as trialkoxyvinylsilane, were observed to give polymers of low molecular weight in high yields in the polymerization with di‐ tert ‐butyl peroxide at high temperatures (130–150 °C) 7, 8. The resulting poly(TMVS) was further hydrolyzed with acid catalyst to give polyvinylpolysilsesqioxane as an organic–inorganic hybrid 8…”

Synthesis of hyperbranched polymethylvinylborosiloxanes and modification of addition‐curable silicone with improved thermal stability

“…A weak peak at 2.09 ppm corresponded to hydrogen in B―OH groups . The weak peaks at 3.17–3.58 ppm corresponded to hydrogens in Si―OCH 3 groups that remained as different terminal groups . The Si―CH 3 group was selected as a reference because it did not participate in condensation.…”