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Colorless transparent vulcanizates of silicone elastomers were prepared by mixing the components in a common solvent followed by solvent removal. We studied the correlation between the mechanical behavior of polydimethylsiloxane (PDMS)-rubber compositions prepared using MQ (mono-(M) and tetra-(Q) functional siloxane) copolymers with different ratios of M and Q parts as a molecular filler. The composition and molecular structure of the original rubber, MQ copolymers, and carboxyl-containing PDMS oligomers were also investigated. The simplicity of the preparation of the compositions, high strength and elongation at break, and their variability within a wide range allows us to consider silicone elastomers as a promising alternative to silicone materials prepared by traditional methods.

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Nanogels can be called the new old§ objects of polymer chemistry. New because we have formulated the criteria for the assignment of objects to this group within the macromolecule-particle concept and developed the methods for their directed and controlled synthesis. Old because the application of these criteria to the earlier known systems allow us to surely classify them as nanogels. It is shown that this classification per se provides insight into the organization of their molecular structures and enables directed modification. This means a transition from the empirical control of the properties to molecular design. The current review presents a brief historical overview of densely cross-linked nanogels and their main synthetic routes and highlights the principles and approaches to the control of their structures and molecular-mass characteristics, application scope, and prospects for further development.

Comb-like polymethylsiloxanes consisting of a silsesquioxane backbone and dimethylsiloxane side chains were synthesized by means of the "grafting to" method using a linear polyfunctional matrix [SiMe(ONa)O] n and monofunctional oligomers (CH 3 ) 3 Si[OSi(CH 3 ) 2 ] n OCOCH 3 . The effects of architecture of the synthesized methylsiloxane polymers on their physicochemical properties, rheology, and behavior at the air-water interface were studied and compared with those for the linear analoguepolydimethylsiloxane.

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Polycondensation of diethoxydimethylsilane (DEDMS) in an active medium containing an excess of acetic acid was studied. It has been shown that the process selectivity could be well managed only if water was generated in the reaction mixture. We have found that both linear oligomers and cyclosiloxanes could be obtained with high selectivity and 80 % yield at least under conditions of the active medium. Further condensation of the linear oligomers led to the formation of α, ω-dihydroxypolydimethylsiloxanes with the molecular weight ranging from 3500 to 70000 Da. The obtained polydimethylsiloxane samples having hydroxyl end groups correspond to the industrial samples of liquid siloxane rubbers in terms of molecular weight parameters and virtually do not contain any low molecular cyclosiloxane impurities.