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Es war eine Sensation, als im Januar dieses Jahres die Nachricht um die Welt ging, dass das seit fünfzig Jahren bekannte Magnesiumdiborid MgB2 bereits unterhalb der relativ moderaten Temperatur von 39 K supraleitend wird (siehe Bild). Die kommerziell erhältliche Verbindung war bei der Suche nach neuen Supraleitern einfach übersehen worden.

The nanocomposite of PDMS using functionalized fumed silica and nonreactive POSS as fillers were prepared by blend method in a planetary mixer. Fumed silica was functionalized by aliphatic and aromatic groups to study the filler–filler interactions with the aliphatic and aromatic POSS fillers and consequently their influence on the properties in the PDMS matrix. Transmission electron microscope (TEM) showed a good dispersion in the systems having the silica and POSS fillers with similar modifications. However, aliphatic and aromatic filler combinations showed more aggregated structures. Moreover, aliphatic POSS despite of good dispersion at higher loadings, act as lubricant, which is attributed to the disturbance in the PDMS‐ silica filler interaction and also the filler–filler interaction within fumed silica. There is a decrease in complex viscosity with the functionalization of fumed silica and with the aromatic/aliphatic POSS fillers. The thermal stability of aromatic functionalized fillers improves owing to the thermally stable phenyl groups. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Soluble poly(imide‐siloxane)s were obtained by carefully designing the synthesis and introducing poly(ethylene glycol) (PEG) units, thereby making the system amphiphilic in nature. The solubility of the synthesized PEG containing poly(mide‐siloxane)s (PPIS) in various solvents was tested and their thermal properties were investigated. Polymeric siloxane networks were prepared by combining imide groups and hydrophilic PEG components with sufficient variability in their composition to analyze their physicochemical details. The amine groups of the imides were varied in their rigidity and bulkiness, and their effect on the mechanical and thermal properties was studied. Here we have also examined the surface property of the networks through contact angle measurements, morphology through SEM, existence of amorphous nature by WAXD, and their structure–property relationships were correlated. The thermal analysis revealed the phase separation of the three components poly(dimethyl siloxane) (PDMS), PEG, and imide, showing a tricomponent amphiphilic conetworks. The mechanical properties were found to be improved by the phase separated PPIS containing more rigid imide groups. The overall properties of the amphiphilic conetwork has the features of differing hydrophilicity, mobility, and morphology distributed across a matrix, which has a microphase separated design suitable for gas separation and biomedical applications. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1707–1726, 2007

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