Godinho M H, Pieranski P, Sotta P
CENIMAT - Centro de Investigaçao em Materiais, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa Campus da Caparica, 2829 - 516, Caparica, Portugal.
Laboratoire de Physique des Solides, UMR 8502, Université Paris-Sud, Bât. 510, 91405, Orsay, France.
Eur Phys J E Soft Matter. 2016 Sep;39(9):89. doi: 10.1140/epje/i2016-16089-2. Epub 2016 Sep 29.
The hygroscopic method developed previously for studies of lyotropic liquid crystals is used for the first time in experiments with millimetric capillary bridges made of a hydroxypropylcellulose/water mixture. Composition of such very small samples is controlled via humidity of the surrounding air. By a slow and well-controlled drying of initially isotropic samples, the isotropic/anisotropic phase transition is crossed and polydomain pseudo-isotropic capillary bridges are prepared. Kept in an atmosphere of constant humidity, these bridges are stretched and the strain-induced birefringence [Formula: see text] n is measured as a function of the draw ratio [Formula: see text] . The variation of [Formula: see text] n with [Formula: see text] is interpreted in terms of an affine uniaxial deformation of the initial pseudo-isotropic texture.
先前开发的用于研究溶致液晶的吸湿方法首次用于由羟丙基纤维素/水混合物制成的毫米级毛细管桥的实验中。通过周围空气的湿度来控制这种非常小的样品的组成。通过对初始各向同性样品进行缓慢且控制良好的干燥，跨越各向同性/各向异性相变，制备了多畴伪各向同性毛细管桥。将这些桥保持在恒定湿度的气氛中，进行拉伸，并测量应变诱导双折射Δn作为拉伸比λ的函数。根据初始伪各向同性织构的仿射单轴变形来解释Δn随λ的变化。
