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Multiarm Star-Shaped Polydimethylsiloxanes with a Dendritic Branching Center.

ABSTRACT: New multiarm stars have been synthesized based on polylithium derivatives of high-generation carbosilane dendrimers. In the synthesis of multiarm stars based on the eighth-generation dendrimer, steric hindrances were observed even during the synthesis of a polylithium initiator. Subsequently, this led to chain transfer reactions between growing arms, as well as other side effects. As a result, dense nanogel formations with a higher tendency of ordering than in classical objects of this type were isolated from the reaction mixture. The study of the rheology of multiarm stars based on sixth-generation dendrimers made it possible to determine the activation energies of viscous flow in these objects, which makes it possible to consider them as objects with a macromolecular nature and a reptation flow mechanism.

SUBMITTER: Tikhonov PA

PROVIDER: S-EPMC8199136 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature

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Multiarm Star-Shaped Polydimethylsiloxanes with a Dendritic Branching Center.

Tikhonov Pavel A PA Vasilenko Nataliya G NG Gallyamov Marat O MO Cherkaev Georgii V GV Vasil'ev Viktor G VG Demchenko Nina V NV Buzin Mikhail I MI Vasil'ev Sergey G SG Muzafarov Aziz M AM

Molecules (Basel, Switzerland) 20210529 11

New multiarm stars have been synthesized based on polylithium derivatives of high-generation carbosilane dendrimers. In the synthesis of multiarm stars based on the eighth-generation dendrimer, steric hindrances were observed even during the synthesis of a polylithium initiator. Subsequently, this led to chain transfer reactions between growing arms, as well as other side effects. As a result, dense nanogel formations with a higher tendency of ordering than in classical objects of this type were ...[more]

PMID: 34072317

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