Get access
Advertisement

Vinyl-terminated liquid-crystalline dendrimers based on dendritic polyols and their siloxane-based elastomers

Authors

  • Yuteng Lin,

    1. State Key Laboratory of Chemical Engineering, Department of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
    Search for more papers by this author
  • Jianzhong Sun

    Corresponding author
    1. State Key Laboratory of Chemical Engineering, Department of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
    • State Key Laboratory of Chemical Engineering, Department of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
    Search for more papers by this author

Abstract

A new series of side-chain liquid-crystalline dendrimers (LCDs) by grafting vinyl-terminated phenyl benzoate-based promesogens to a novel polypropyleneimine-derived dendritic polyols are reported. Polarized optical microscopy and X-ray diffraction studies show that both the compounds display a smectic-A (SmA) mesophase. The second-generation dendrimer bearing eight-branched promesogens exhibits a more stable SmA mesophase with a wide mesomorphic temperature range. It is demonstrated that “promoting groups” in the structure of LCD for the enhancement of mesomorphic stability are unnecessary in the case of strong anisotropic interactions. In contrast to conventional LCDs, these two compounds possess reactive vinyl terminals that endow them with the potential for the preparation of polymeric materials. For the first time, a type of thermoset elastomers is explored from LCDs via hydrosilylation crosslinking reaction of vinyl terminals and siloxane crosslinker. Two-dimensional X-ray diffraction study indicates that the lamellar structures of original dendrimers are reserved in the elastomer networks. Stress–strain curves reveal that these elastomers exhibit excellent elasticity under successive uniaxial compression. The combination of anisotropic structures of rigid units and elasticity of flexible networks in this novel series of elastomers makes them promising candidates for the application in artificial muscles or cartilages. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013

Get access to the full text of this article

Ancillary