Silicon‐based materials prepared by IPN formation and their properties

Abstract

Both "condensation" and "hydrosilylation" reactions have been successfully applied to the synthesis of silicon-based interpenetrating polymer networks (IPNs) consisting of a stable Si-O and/or a Si-C linkage. A ladder silsesquioxane oligomer (LDS 1, commercial name: Glass Resin™ GR100) and a polycarbosilane (PCS) by hydrosilylation polymerization of bifunctional Si-H and Si-vinyl monomers were used as the two components for the IPN (Table I). Si-based IPN material was prepared by melt-and-compression-molding method of the B-staged resin. Evaluating the flowcuring nature of the B-staged resin thus obtained with a KOKA-type flow tester led to suitable conditions for melt-and-compression molding. LDS/PCS materials with various shapes (3-4 mm thick) were prepared by melt-and-compression molding. The mechanical properties of the LDS/PCS materials were evaluated. The flexural modulus and Izod impact strength of LDS/PCS (8:2 w/w) were larger than those of each component, a tendency that proved to be a positive effect derived from IPN formation in the LDS/PCS combined system. In addition, the thermal, electrical, and optical properties of these silicon-based materials were studied and are reported on.

Synthesis of Organic−Inorganic Hybrid Gels from Siloxane or Silsesquioxane and α,ω-Nonconjugated Dienes by Means of a Photo Hydrosilylation Reaction

“…Organic−inorganic hybrid polymers usually have characteristics derived from both the organic and inorganic components. Various types of organic−inorganic hybrid polymers that contain Si have been synthesized by a variety of synthetic methods including condensation reaction, hydrosilylation, and so on. – Hydrosilylation of multifunctionalized cross-linking reagents containing Si−H or vinyl groups is one useful method for synthesizing organic−inorganic hybrid polymers having network structures. – We think that the precise control of the network structures and the fundamental characterization of the organic−inorganic hybrid gel is essential not only to improve properties but also to develop novel network polymers with specific features. The authors recently developed organic−inorganic hybrid gels by means of hydrosilylation of a cyclic siloxane or a cubic silsesquioxane with α,ω-nonconjugated dienes using a highly efficient hydrosilylation catalyst, platinum−divinyltetramethyldisiloxane complex (Karstedt’s catalyst), and quantitatively characterized the network structures of the gels by means of a characteristic analytical method, namely, scanning microscopic light scattering (SMILS). , In a previous investigation, we synthesized organic−inorganic hybrid gels having homogeneous network structure with controlled mesh sizes ranging from 0.5 to 5 nm by means of the hydrosilylation reaction between tetrafunctional cyclic siloxane (1,3,5,7-tetramethylcyclotetrasiloxane, TMCTS) and 1,5-hexadiene (HD) or 1,7-octadiene (Scheme ) .…”

Flame-retardant epoxy resins: An approach from organic-inorganic hybrid nanocomposites

“…In recent years, many works have focused on the study of organic–inorganic hybrid materials, which were considered innovative advanced materials promising new applications in many fields, such as optics, electronics, mechanics, and biology 1–15. Many polymers, including polyimide, epoxy, polystyrene, poly(dimethyl siloxane), and poly(hydroxyethyl methacrylate), have been used to produce hybrid materials.…”

Organosilicon – Organic Hybrid Polymers and Materials

“…For example, such resins were obtained by hydrosilylation of divinyl (or dialkynyl) species with octahydrido POSS in the presence of Karstedt's catalyst: Ladder silsesquioxane oligomer and policarbosilane were used as the components of the silicon based interpenetrating networks, IPN. Polycarbosilane was synthesised by hydrosilylation polymerisation of bifunctional Si-H and Si-vinyl monomers, catalysed by Karstedt's catalyst [121,122].…”