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A series of new molecular hybrids with stilbene chromophore (H1−H4) are prepared by hydrosilylation of octahydridosilsesquioxane (T8H). All these stilbene-containing hybrid materials are soluble in common organic solvents, such as chloroform, toluene, THF, and 1,2-dichloroethane, and possess good film-forming properties. Their structures and properties are characterized and evaluated by FT-IR, NMR, UV, PL, TGA, DSC, nonlinear optical (NLO), and optical limiting (OL) analyses. The results show that the thermal decomposition temperatures (Td, 5 mass % loss) of the hybrids are 20−60 °C greater than their corresponding stilbene monomers, and the hybrids show obvious nonlinear absorption (β up to 2.56 × 10−11 m/W) and optical limiting properties. The larger excited-state absorption cross sections than corresponding ground-state absorption cross sections of the hybrids indicate that reverse saturable absorption is a major mechanism responsible for the optical limiting of the hybrids.

A series of soluble polyhedral oligomeric silsesquioxane (POSS) based inorganic−organic hybrid nonlinear optical materials with different architectures, such as dumbbell-type, bead-type and network-type structure, were prepared based on the hydrosilylation addition reaction of multifunctional octahydridosilsesquioxane (T8H) with different azobenzene chromophore monomers. These resultant hybrid composites are soluble in common organic solvents such as tetrahydrofuran, toluene, and chloroform, and exhibit good film-forming ability. Their structures and properties were characterized and evaluated with IR, 1H NMR, 29Si NMR, TGA, DSC, optical limiting measurement and Z-scan technique, respectively. The results show that the structure of these resultant hybrids can be effectively tuned by simply varying the feed ratio and molecular structure of organic chromophore monomers. The incorporation of inorganic POSS into organic azobenzene chromophore has endowed the hybrids with well optical limiting properties and h...

A series of novel hybrid poly(acetoxylstyrene-co-isobutylstyryl-POSS)s (PAS−POSS) and poly(vinylpyrrolidone-co-isobutylstyryl-POSS)s (PVP−POSS) are synthesized and characterized. The POSS content in these hybrids can be controlled by varying the monomer feed ratio. The polyhedral oligosilsesquoixane (POSS) moiety can effectively increase the Tg of the resultant organic/inorganic hybrid polymer at a relatively high POSS content and produce the hybrid copolymer with narrower molecular weight distribution. The FTIR spectra are used to investigate the structure−property relationship of these hybrid polymers, and the Tg enhancement mechanism is discussed in detail.

Most of the existing metal carbonyl catalysts for acetylene polymerizations need to be preactivated by chlorine-containing additives or by UV irradiation in halogenated solvents. In this work, we developed a series of “simple” metal carbonyl catalysts of general structure M(CO)xLy (M = Mo, W), none of which require additives or pre-photoirradiation, most of which are air- and moisture-stable, and some of which work well in nonhalogenated solvents. The acetonitrile complexes M(CO)3(NCCH3)3 initiated polymerizations of a variety of mono- and disubstituted acetylenes at room temperature. The arene and diene complexes W(CO)3(mes) and Mo(CO)3(nbd) (mes = mesitylene, nbd = 2,5-norbornadiene) are tolerant of polar groups and effected polymerizations of functional acetylenes containing ester, ether, and cyano groups. The halogenated complexes MI2(CO)3(NCCH3)2 catalyzed polymerizations of phenylacetylene in toluene. The chlorine-containing acetylene monomers ClC⋮CC6H5 and ClC⋮CC6H13 were readily polymerized by the...

Carbon nanotube-containing poly(phenylacetylenes) (NT/PPAs) are prepared by in situ polymerizations of phenylacetylene catalyzed by WCl6−Ph4Sn and [Rh(nbd)Cl]2 (nbd = 2,5-norbornadiene) in the pres...