Side-chain liquid-crystalline elastomers

The units giving rise to the liquid-crystalline behavior can be in the side chains. Although most of the polymers studied have been linear, there has been some work on hyperbranched or comb-like structures. The orientation of the mesogenic groups is important. Frequently backbones include siloxanes and acrylates, but a variety of other structures [Pg.38]

The side chains in these structures can rearrange either parallel or perpendicular to the deformed chain backbone,as illustrated in figure 3.2. The outcome depends on the nature and length of the flexible spacer connecting the mesogenic groups to the chain backbone. As expected, the physical properties can become strongly anisotropic. [Pg.39]

The phase transitions depend significantly on spacer length, as has been demonstrated for oligo-oxyethylene spacers.Closer coupling between the mesogenic groups and the polymer backbone tends to make the system more sensitive to the mechanical deformation, at least in the case of methylene groups in the spacer. [Pg.39]

Relatively high degrees of cross linking can be introduced without destroying the liquid crystallinity. Cross linking can generally be induced [Pg.39]

Approximately parallel and perpendicular arrangements of mesogenic side groups on a chain backbone stretched in the vertical direction. [Pg.39]

Side-Chain liquid-crystalline elastomers 9.3.1 Some general aspects... [Pg.368]

Only comparatively few dynamic mechanical measurements in the vicinity of the nematic-isotropic transition have been reported these include some for side-chain liquid crystalline elastomers [7, 8], and some for liquid crystalline elastomers with mesogenic groups in the main chains and in the side-chains (combined LCE) [9]. The latter reference describes the evaluation of... [Pg.278]

In addition to the phase transitions de-seribed so far, a number of other phase transitions involving liquid crystalline phases has been reported. These include for side-chain liquid crystalline elastomers SmC-I [32], N-SmA [6, 30], N-SmF [32], SmA-SmC [32], SmA-SmB [32] and SmC-SmF [32], Furthermore, a phase transition between a SmA phase and a re-entrant... [Pg.290]

Zanna JJ, Stein P, Marty JD, Mauzac M, Martinoty P. 2002. Influence of molecular parameters on the elastic and viscoelastic properties of side chain liquid crystalline elastomers. Macromolecules 35 5459 5465. [Pg.144]

Gleim, W., and Finkelmann, H., Side chain liquid crystalline elastomers, in Side Chain Liquid Crystal Polymers (C. B. McArdle, ed.), Blackie, Glasgow. 1989, pp. 287-308. [Pg.1184]

Rogez D, Martinoty P (2011) Mechanical properties of monodomain nematic side-chain liquid-crystalline elastomers with homeotropic and in-plane orientation of the director. Eur Phys J E Soft matter 34(7) 69. doi 10.1140/epje/i2011-11069-8... [Pg.85]

Sanchez-Ferrer A, Fischl T, Stubenrauch M, Wurmus H, Hoffmann M, Finkelmann H (2009) Photo-crosslinked side-chain liquid-crystalline elastomers for microsystems. Macromol ChemPhys 210(20) 1671-1677. doi 10.1002/macp.200900308... [Pg.89]

Gleim W, Finkehnann H (1989) Side chain liquid crystalline elastomers. In McArdle CB (ed) Side chain liquid crystalline polymers. Blaclde and Son, Glasgow... [Pg.91]

Selected Mechanical Properties of Uniaxial Side Chain Liquid Crystalline Elastomers... [Pg.41]

Sanchez-FerrCT A, Finkehnann H (2013) Opto-mechanical effect in photoactive nematic main-chain liquid-erystalline elastomers. Soft Matter 9 46214627 Sanchez-FerrCT A, Merekalov A, Finkehnann H (2011) Opto-mechanical effect in photoactive nematic side-chain liquid-crystalline elastomers, macromol. Rapid Commun 32 671-678 Shankar MR, Smith ML, Tondiglia VP, Lee KM, McConney ME, Wang DH, Tan LS, White TJ (2013) Cmitactless, photoinitiated snap-through in azobenzene-functionalized polymtas. Proc Natl Acad Sci 110 18792-18797... [Pg.457]

Nair B R, Gregoriou V G and Hammond P T (2000) FT-IR studies of side chain liquid crystalline elastomers. Polymer 41 2961-2970. [Pg.32]

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