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Synthesis of Block and Graft Copolymers Containing Liquid Crystalline Segments

  • Ailton S. Gomes
  • Maurício R. Pinto
  • Celton A. Barbosa

Abstract

Block and graft copolymers are interesting state of matter in respect to their morphologies, while the liquid crystalline state contribute with unique thermal scientific and and flow properties. The combination of these different states of matter has been allowed many technological attributes to the obtained materials. If a system is composed by segregated amorphous and side chain liquid crystalline segments, some desirable and eligible non-LC characteristics can be originate from the non-LC moieties without critical disturbance of the mesomorphic properties of the LC counterparts. For example: mechanical strength and stiffness, film forming and compatibilizing aid. In this way, the liquid crystalline state can be physically supported by a stiff and resilient film. Several relevant and recent methodologies of synthesis have been worked up: (i) polymer-analogous reaction of AB type prepolymers (Adams et al., 1994; Arnold et al., 1994); (ii) ionic living block copolymerization between conventional and LC monomers and organometallic catalyzed living insertion polymerization (Bohnert and Finkelmann, 1994; Yamada et al., 1995) and (iii) the use of macromonomer and macroinitiator systems (Pugh and Percec, 1986; Chiellini and Galli, 1994). Our synthetic goal to the synthesis of block and graft copolymers are based on:
  1. (1)

    radical polymerization of a liquid crystalline acrylate monomer (LC monomer) in the presence poly(ethylene-co-vinyl acetate) functionalized with thiol groups as macrotransfer agent;

     
  2. (2)

    chemical modification of poly(styrene-b-acrylic acid), ionomers and t-butyl ester derived therefrom by reactive low molecular weight liquid crystals and,

     
  3. (3)

    radical block copolymerization between styrene and a LC monomer by INIFERTER techniques.

     

Keywords

Block Copolymer Graft Copolymer Copolymer Sample Liquid Crystalline State Critical Disturbance 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. Adams, J., Sänger, J., Tefehne, C., and Gronski, W., 1994, Liquid-crystalline/amorphous diblock and triblock copolymers-influence of morphology and microstructure on phase behaviour, Macromol. Rapid Commun., 15: 879–886.CrossRefGoogle Scholar
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Copyright information

© Springer Science+Business Media New York 1998

Authors and Affiliations

  • Ailton S. Gomes
    • 1
  • Maurício R. Pinto
    • 1
  • Celton A. Barbosa
    • 1
  1. 1.Instituto de Macromoléculas Professora Eloisa ManoUFRJRio de JaneiroBrasil

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