Twin polymerization is a novel modular approach for the synthesis of hybrid materials. Using this strategy two distinct polymers of either inorganic or organic nature are produced from a single source monomer in a mechanistically coupled process. Twin polymerization is an elegant way for producing nanostructured organic‐inorganic hybrid materials of composition and morphology on demand. The main objective of this Review is the explanation of the principle of various twin polymerization processes and their appropriate terminologies. Different types of twin polymerization are classified with respect to the underlying processes as described in individual examples, demonstrating its potential in material synthesis. Prospects of the synthetic methodology of twin polymerization are demonstrated for different molecular structures of twin monomers and the resulting hybrid materials. A comparison with other scenarios for the synthesis of two different polymers within one procedure is included.
In the present work, bilayered hybrids obtained by hydrosilylation of polysiloxane with carbazolyl moieties (Sil-Cz) and polyfluorene (Sil-PFO) had their photophysical behavior, morphological characteristics and interaction properties studied for applications in electroluminescent devices. Fluorescence spectra of the Sil-Cz did not show emission in the excimer/aggregate region (from 400 to 500 nm). This is an unexpected behavior since most of the carbazole-based materials present excimer and aggregation. Nonetheless, this unusual observation was also predicted by geometry optimization calculations. Fluorescence spectra were taken for both compounds separately and for the bilayered system show some evidence of interaction between carbazolyl and polyfluorene moieties, giving rise to the supposition that the can form a system with tunable luminescent properties. 相似文献
The spectroscopic behavior of ionic Eu3+ or Tb3+ complexes of an aromatic carboxyl‐functionalized organic salt as well as those of the hybrid materials derived from adsorption of the ionic complexes on Laponite clay are reported. X‐ray diffraction (XRD) patterns suggest that the complexes are mainly adsorbed on the outer surfaces of the Laponite disks rather than intercalated within the interlayer spaces. Photophysical data showed that the energy‐transfer efficiency from the ligand to Eu3+ ions in the hybrid material is increased remarkably with respect to the corresponding ionic complex. The hybrid material containing the Eu3+ complex shows bright red emission from the prominent 5D0→7F2 transition of Eu3+ ions, and that containing the Tb3+ complex exhibits bright green emission due to the dominant 5D4→7F5 transition of Tb3+ ions. 相似文献
Polyhedral oligomeric silsesquioxane with phenethyl substituents (PhenethylPOSS) as nanofiller was incorporated within Poly(bisphenol A carbonate) (PBAC) as matrix. Dielectric spectroscopy proved an almost complete miscibility of PhenethylPOSS up to 7 wt. %. At higher concentrations phase separation yields composites with a PBAC-rich matrix and POSS-rich domains which posses well shaped interfaces. The nanocomposites were also investigated with respect to their gas transport behaviour. An increase of the gas permeability was found at higher PhenethylPOSS concentrations, which is due to the phase separated structure. 相似文献
Conducting polymer based hybrid materials were synthesized by a new route. The use of pyrrole derivatives functionalized by a carboxylic acid or a -diketone group allows to control the polymerization rate of zirconium tetrapropoxide (Zr(OPr)4). The organic species entrapped in the resulting hybrid materials yield conducting polymers by electropolymerization. The results show that the formation of the conducting polymers depends on the nature of the monomer. Moreover, the presence of polysiloxane chains within the hybrid materials improves the properties of the latter. 相似文献
High‐molecular‐weight conjugated polymer HD‐PDFC‐DTBT with N‐(2‐hexyldecyl)‐3,6‐difluorocarbazole as the donor unit, 5,6‐bis(octyloxy)benzothiadiazole as the acceptor unit, and thiophene as the spacer is synthesized by Suzuki polycondensation. HD‐PDFC‐DTBT shows a large bandgap of 1.96 eV and a high hole mobility of 0.16 cm2 V−1 s−1. HD‐PDFC‐DTBT:PC71BM‐based inverted polymer solar cells (PSCs) give a power conversion efficiency (PCE) of 7.39% with a Voc of 0.93 V, a Jsc of 14.11 mA cm−2, and an FF of 0.56.
The main challenge of commercialization of the hydrogen economy is the lack of convenient and safe hydrogen storage materials, which can adsorb and release a significant amount of hydrogen at ambient conditions. Finding and designing suitable cost‐effective materials are vital requirements to overcome the drawbacks of investigated materials. Because of its outstanding electronic, thermal, and chemical properties, the electrically conducting polyaniline (PANI) has a high potential in hydrogen storage applications. In this review, the progress in the use of different structures of conducting PANI, its nanocomposites as well as activated porous materials based on PANI as hydrogen storage materials is presented and discussed. The effect of the unique electronic properties based on the π‐electron system in the backbone of these materials in view of the hydrogen uptake and the relevant mechanisms are highlighted.
We report the synthesis of the first organo‐POM with thermoresponsive properties. Our concept will provide chemists with a new tool to design POMs whose solubility is reversibly controllable through an external stimulus. POM–polymer TBA7[POM]‐poly(N,N‐diethylacrylamide) (POM–PDEAAm), was prepared by grafting PDEAAm‐NH2 (obtained by RAFT polymerization) onto the activated Dawson acyl‐POM, α2‐[P2W17O61SnCH2CH2C(?O)]6?. Extensive MS analysis was used to monitor the chain‐functionalization steps and to confirm the formation of the hybrid. Aqueous solutions of the (NH4)7[POM–PDEAAm] exhibited a LCST of 38 °C. Thus, the solubility/aggregation of the hybrid was reversibly controlled by changing the temperature. Above 38 °C, the solution became cloudy, and cleared again upon cooling. Dynamic light scattering (DLS) revealed the formation of small aggregates in the range 100 nm. We assumed that the charged POM head units prevented the formation of the larger‐scattering aggregates that are usually observed for PDEAAm, and promoted the formation of micelle‐like structures. The conjugate exhibited a temperature transition, which was different from that of the polymer and depended on the counterions associated with the POM. This result demonstrates the potential for merging organic (in this case, polymer) and inorganic structures to afford materials that exhibit new properties. 相似文献
A series of poly{(3‐hexylthiophene)‐co‐[3‐(6‐hydroxyhexyl)thiophene]}:titania (P3HT‐OH:TiO2) hybrids were synthesized via the in situ polycondensation of titanium (IV) n‐butoxide in the presence of P3HT‐OH. Introducing a hydroxyl moiety onto the side‐chain of poly(3‐hexylthiophene) (P3HT) significantly promotes the polymer‐titania interaction, resulting in the formation of homogeneous hybrid colloids. The UV‐vis spectra of P3HT‐OH:TiO2 films demonstrate that TiO2 markedly affects the stacking structure and the chain conformation of P3HT‐OH. The maximum absorption wavelength of these hybrid materials can be tailor‐made by merely varying the weight percentage of TiO2. Moreover, P3HT‐OH:TiO2 can be further utilized as an efficient compatibilizer in preparing photoactive P3HT:P3HT‐OH:TiO2 films with excellent miscibility. The photovoltaic cell based on such a hybrid exhibited a 2.4‐fold higher value of power‐conversion efficiency compared to the cell based on P3HT:TiO2.
The photoluminescence (PL) of CdSe quantum dots (QDs) that form stable nanocomposites with polymer liquid crystals (LCs) as smectic C hydrogen‐bonded homopolymers from a family of poly[4‐(n‐acryloyloxyalkyloxy)benzoic acids] is reported. The matrix that results from the combination of these units with methoxyphenyl benzoate and cholesterol‐containing units has a cholesteric structure. The exciton PL band of QDs in the smectic matrix is redshifted with respect to QDs in solution, whereas a blueshift is observed with the cholesteric matrix. The PL lifetimes and quantum yield in cholesteric nanocomposites are higher than those in smectic ones. This is interpreted in terms of a higher order of the smectic matrix in comparison to the cholesteric one. CdSe QDs in the ordered smectic matrix demonstrate a splitting of the exciton PL band and an enhancement of the photoinduced differential transmission. These results reveal the effects of the structure of polymer LC matrices on the optical properties of embedded QDs, which offer new possibilities for photonic applications of QD–LC polymer nanocomposites. 相似文献
Nitrogen-linked hexaazatrinaphthylene polymer ( N2-HATN ) as organic cathode material with low HOMO–LOMO gap was synthesized and was observed to possess reversible high capacity and unexpected long-term cycling stability. The pre-treated N2-HATN and pRGO combination demonstrated good structure compatibility and the resultant cathode exhibited a constant increment of capacity during the redox cycles. The initial capacity at 0.05 A g−1 was 406 mA h−1 g−1, and increased to 630 mA h−1 g−1 after 70 cycles. At 0.5 A g−1 discharging rate, the capacity increased from an initial value of 186 mA h−1 g−1 to 588 mA h−1 g−1 after 1600 cycles. The pseudocapacitance-type behavior is postulated to be attributed to the structure compatibility between the active material and pRGO. 相似文献
The development of magnetic nanoparticles with multiple functions has been an ever‐growing field because of their diverse applications in drug delivery, biosensing, cell labeling, and so on. In this study, a facile method was developed to construct multifunctional magnetic nanocomposites. The approach is based on the use of poly(glycidyl methacrylate), PGMA, with numerous epoxy groups as reactive polymer to combine with fluorescent dye, the surface of magnetic nanoparticles, and targeting ligands directly without expatiatory functionality design. The resultant nanocomposites with good superparamagnetic and fluorescent properties could be exploited for bioimaging. Moreover, after conjugation with a model protein, namely, transferrin, which specifically targets cells overexpressing transferrin receptors, the nanocomposites could be used selectively to recognize Hela cells in comparison with nonconjugated ones. These results indicate that the newly designed magnetic nanocomposites with PGMA as functional polymer could serve as a novel versatile platform to conjugate with various molecules for construction of diverse multifunctional magnetic nanocomposites to meet different requirements and potential uses in nanomedicine and biological chemistry. 相似文献
Vesicles can be individually fabricated from naturally occurring lipid or synthetic block copolymer molecules via self‐assembly in aqueous solutions; the blending of both vesicle‐forming amphiphiles leads to the formation of hybrid membranes. Their final stabilities and lateral morphologies are strongly determined by the molar composition, size, and charge properties of the interacting components as well as by the lipid chain melting temperature. Upon merging the best properties of lipo‐ and polymersomal membranes, hybrid lipid/polymer vesicles represent a new scaffold for medical applications combining, e.g., combining the biocompatibility of liposomes with the high thermal and mechanical stability and functional variability of polymersomes within a single vesicle type. Up to now, several hybrid membrane systems and their corresponding vesicular morphologies have been studied, highlighting the attractive properties and features useful in selective delivery receptor scaffolding.