A high surface area porous hybrid material was synthesized by one-step click chemistry, which captures 1.83 mmol g−1 CO2 at 273 K.

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Several new poly(alkylarylsilane)s, [Et 3 Si(CH 2 ) 2 Si(C 6 H 4 R)] n [R = H (1), p-Me (2), p-OMe (3), p-NMe 2 (4)] with M w = 2.9-4.6 Â 10 3 and PDI = 1.41-1.64, have been synthesized by dehalocondensation of appropriate dichlorodiorganosilanes using Na dispersion in refluxing toluene. The σ-σ* electronic transitions associated with the silicon backbone of 1-4 exhibit a progressive red shift (λ max : 320-342 nm) as a result of increasing electron donating ability of the substituent on the phenyl ring. This intrinsic optimization of band gap energy has been considered as a measure of oxidation potential of these polysilanes which varies in the following order: 1 > 2 > 3 > 4. The result obtained from electronic spectra is further confirmed by electrochemical studies using cyclic voltammetry which reveals a lowering of the oxidation potential (V peak ) from 0.95 to 0.49 V in the polysilanes 1-4. These polysilanes act as reducing agents of variable strengths toward Ag(I) and Pd(II) ions and afford the formation of metal nanoparticles with optimized size domains [21.0-4.8 nm for Ag; 31.6-16.6 nm for Pd], the smaller size nanoparticles being formed by the use of polysilanes with lower oxidation potential (or higher λ max ). The polymer-metal nanocomposites have been characterized by NMR and UV-vis spectroscopy as well as powder X-ray diffraction, TEM, and DLS studies.

The network polysilanes (polysilynes) [RMe2SiCH2CH2Si]n, [R=Ph (1), 2‐Furyl (2)] have been synthesized by room temperature reaction of the corresponding organotrichlorosilane with Na dispersion in tetrahydrofuran (THF) medium. The method allows the formation of high molecular weight polymers [Mw/PDI = 10,504/2.2 (1), 9176/1.5 (2)] in improved yields than those obtained from classical Wurtz coupling reaction (Na, toluene, 110 °C). These polymers act as reducing agents for Ag(I) and Au(III) ions to afford stable metal nanoparticles of 4–8 nm size domains in toluene medium. The corresponding polymer–silver nanocomposites, 1a and 2a, are fluorescent in the green light region (λmax = ∼ 530 nm) due to the formation of silver nanoclusters (AgNCs) along with the nanoparticles (AgNPs). A simple chemical approach has been developed to modulate the plasmonic and emission intensities of the nanocomposite 1a by reacting with varying concentrations (10−12 to 10−7M) of HgI2 in toluene. The method allows enhancement of the fluorescence intensity associated with AgNCs. The results are explained by invoking coupling between the energies of surface plasmon resonance and the nanocluster electronic transition. The polymer–gold nanocomposites, 1b and 2b, are non‐fluorescent and the plasmonic resonance at 530 nm associated with AuNPs is found to be insensitive to Hg(II) ions. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012

Poly(hydrosilane)s, [R(H)Si]n [R = Ph, Si(CH2)3SiMe2Th, cy‐Hex], are investigated as sources of silyl radicals. The Si–H bonds in these oligomers exhibit good to excellent hydrogen donating properties which ensure the formation of reactive silyl radicals. For free radical photopolymerization, the polymerization initiating properties of these structures are checked. These polymers are found to be advantageous to overcome the classical oxygen inhibition of the FRP process. Their ability in FRPCP is also evaluated for an epoxy monomer. The mechanisms are investigated through ESR and laser flash photolysis experiments. magnified image

Herein, the evaluation of four commercial alkoxysilanes and two laboratory synthesized novel diethoxysilacycloalkanes as external donors towards propylene polymerization has been done.

The branched polysilane [(PhMeSi)0.8‐co‐(Et3Si(CH2)2Si)0.2]n (PS‐1) as well as the network polysilane [Et3Si(CH2)3Si]n (PS‐2) have been investigated as new polymerization photoinitiating structures. The behavior of PS‐1 was compared with that of [(PhMeSi)]n to demonstrate the enhancement of the photoinitiation for the branched system. As a result of the Si–Si bond cleavage under light and the formation of reactive silyl radicals or silyl cations, these compounds act as efficient photoinitiators (PIs) for free radical photopolymerization (FRP) and free radical promoted cationic polymerization (FRPCP). The polymerization initiating ability of PS‐1 is higher than that of PS‐2 under air. The initiating ability for the ring‐opening polymerization of epoxides is excellent for PS‐1. These polymeric PIs overcome the classical oxygen inhibition in FRP or FRPCP.

Linear polysilanes, [{PhHSi} x {Ph(RSCH 2 CH 2 CH 2 )-Si} 1Àx ] n [R ¼ n-dodecyl (1), n-hexyl (2), n-butyl (3)], have been synthesized and their reactivity with HAuCl 4 Á3H 2 O (Polymer:Au ¼ 10:1, RT, toluene) examined to gain an insight into the role of polymer-supported thioether groups in the stabilization of in situ generated gold nanoparticles (AuNPs). The method allows a simple approach for expeditious synthesis of assemblies of AuNPs comprising of well-separated individual nanoparticles of average diameter 4.5 6 1.9 nm. In this regard, polysilane 1 with dodecyl side chains serves as a superior matrix than 2 and 3 and confers long shelf-life stability to the nanoparticle assembly. The structural attributes are preserved in Au-Pd bimetallic nanoparticles which have been synthesized from the polymer-gold nanoassembly.