Comparative study of photodegradation and metastability in solution-processed and plasmatic polysilylenes

This study deals with photodegradation and metastability of polysilylenes. Physical properties of chemically prepared poly[methyl(phenyl)silylene] and polysilylenes prepared in radio-frequency and microwave discharges are compared. The position and width of the photoluminescence band due to the main chain excitations for both materials preserve but its intensity strongly depends on the preparation conditions and changes considerably during the photodegradation. The difference in photodegradation rate of both materials is explained by their different susceptibility to silyl radical formation and reverse recombination due to the chain and side groups rigidity.     

Stabilization of carbon black with ionic-hydrophobic polyelectrolytes

The mode of action and efficiency of amphipolar copolymers of different molecular architectures with copolymers consisting of ionic (acrylic acid) and hydrophobic (styrene) constitutional units and sequences (segments, blocks, grafts) as stabilizers of carbon black dispersion are discussed. The pigment-copolymer interactions were investigated by the ESA method as well as lumifuge and rheological measurements. The results indicate that there are distinctive differences in the stabilization behavior depending on the molecular architecture with better results being achieved for block and graft copolymers.     

Lewis acidic organoboron polymers

We have developed a highly efficient new method for the introduction of Lewis acidic boron centers into the side chains of organic polymers. Our methodology involves three steps: (i) the controlled polymerization of a functional monomer, (ii) the exchange of the functional group for Lewis acidic boron centers, and (iii) the fine-tuning of the Lewis acidity of the individual centers through substituent exchange reactions with nucleophiles. This approach gives access to a family of new well-defined organoboron polymers including moderately Lewis acidic poly(arylboronates) and the first examples of highly Lewis acidic fluorinated triarylborane polymers.