Selinger Jonathan V, Jeon Hong G, Ratna B R
Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Code 6900, 4555 Overlook Avenue, SW, Washington, DC 20375, USA.
Phys Rev Lett. 2002 Nov 25;89(22):225701. doi: 10.1103/PhysRevLett.89.225701. Epub 2002 Nov 7.
In liquid-crystalline elastomers, the nematic order parameter and the induced strain vary smoothly across the isotropic-nematic transition, without the expected first-order discontinuity. To investigate this smooth variation, we measure the strain as a function of temperature over a range of applied stress, for elastomers cross-linked in the nematic and isotropic phases, and analyze the results using a variation on Landau theory. This analysis shows that the smooth variation arises from quenched disorder in the elastomer, combined with the effects of applied stress and internal stress.
在液晶弹性体中,向列序参数和诱导应变在各向同性 - 向列相转变过程中平滑变化,没有预期的一级不连续性。为了研究这种平滑变化,我们测量了在一系列外加应力下,向列相和各向同性相交联的弹性体的应变随温度的变化,并使用朗道理论的一个变体来分析结果。该分析表明,这种平滑变化源于弹性体中的淬火无序,以及外加应力和内应力的影响。