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Graphene constitutes a two dimensional sp2 hybridized carbon material with outstanding electrical and mechanical properties. To date, novel methods for producing large quantities of graphene and its derivatives (doped or functionalized graphenes, nanoribbons and nanoplatelets) are emerging, and research dedicated to the fabrication of polymer nanocomposites using graphenes has started. In this Research News, we summarize the synthesis and properties of graphene and its derivatives, and provide an overview of the latest research dedicated to the fabrication of polymer composites for different applications, including mechanical, electrical, optical and thermal. Some of the recently fabricated composites exhibit outstanding properties, however, it is vital to understand the chemistry and physics of the interphases established between the polymer and the graphene surfaces. The challenges in the fabrication of super robust and highly conducting composites using graphenes are also discussed. It is believed that graphene‐based polymer composites will result in commercial products if their interphases and reactivity are carefully controlled.

A new method has been found for monitoring polymerization reactions in situ and in real time. The first moment of fluorescent emission,is calculated from fluorescence spectra as a function of polymerization time and can be successfully correlated with the conversion of functional groups, obtained by an independent technique, with a very low level of experimental scatter. The statistical analysis of the method has been performed; some simple computer experiments allowed to study the influence of the most important experimental variables yielding the confidence interval of knl as a function of the noise to signal ratio. This method was applied with stepwise polyaddition (epoxide curing) and polymerization by free radical mechanisms. 5-Dimethylaminonaphthalene-1-sulfonamide derivatives, 4-dialkylamino-4 0 -nitrostilbene and pyrene were used as probes and/or labels. Other methods reported in the literature have been applied also.Comparison with them reveals that the first moment method is more reliable for monitoring polyaddition reactions.

The aim of this study was to investigate the changes produced in the nanostructures and the photoluminescence spectra of bridged silsesquioxanes containing urea or urethane groups, by varying the relative rates between the self-assembly of organic domains and the inorganic polycondensation. Precursors of the bridged silsesquioxanes were 4,4‘-[1,3-phenylenebis(1-methylethylidene)]bis(aniline) and 4,4‘-isopropylidenediphenol, end-capped with 3-isocyanatopropyltriethoxysilane. The inorganic polycondensation was produced using either high or low formic acid concentrations, leading to transparent films with different nanostructures as revealed by FTIR, SAXS, and 29Si NMR spectra. For the bridged silsesquioxanes containing urea groups the self-assembly of organic domains was much faster than the inorganic polycondensation for both formic acid concentrations. However, the arrangement was more regular and the short-range order higher when the rate of inorganic polycondensation was lower. The photoluminescence spectra of the most ordered structures revealed the presence of two main processes:  radiative recombinations in inorganic clusters and photoinduced proton-transfer generating NH2 + and N- defects and their subsequent radiative recombination. In the less-ordered urea-bridged silsesquioxanes a third process was present assigned to a photoinduced proton transfer in H-bonds exhibiting a broad range of strengths. For urethane-bridged silsesquioxanes the driving force for the self-assembly of organic bridges was lower than for urea-bridged silsesquioxanes. When the synthesis was performed with a high formic acid concentration, self-assembled structures were not produced. Instead, large inorganic domains composed of small inorganic clusters were generated. Self-assembly of organic domains took place only when employing low polycondensation rates. For both materials the photoluminescence was mainly due to radiative processes within inorganic clusters and varied significantly with their state of aggregation.