Nishida Toshihiko, Endo Hitoshi, Osaka Noboru, Li Huan-Jun, Haraguchi Kazutoshi, Shibayama Mitsuhiro
Neutron Science Laboratory, Institute for Solid State Physics, The University of Tokyo, Tokai, Ibaraki 319-1106, Japan.
Phys Rev E Stat Nonlin Soft Matter Phys. 2009 Sep;80(3 Pt 1):030801. doi: 10.1103/PhysRevE.80.030801. Epub 2009 Sep 14.
Contrast-variation small-angle neutron scattering (CV-SANS) was applied to investigate the deformation mechanism of high-performance nanocomposite polymer hydrogels (NC gels) consisting of polymer chains and inorganic clay platelets. Anisotropic SANS functions were obtained at various stretching ratios, lambda 's up to lambda=9 and were decomposed to three partial structure factors, S(ij)(Q parallel,Q perpendicular). Here, the subscripts i and j denote the polymer (P) or clay (C) and Q parallel and Q perpendicular are the magnitude of the scattering vectors along and perpendicular to the stretching directions, respectively. SCC(Q parallel,Q perpendicular) and S_{PP}(Q parallel,Q perpendicular) suggested that the orientation of clay platelets saturated by lambda approximately 3 , while the polymer chain stretching continued by further stretching. On the other hand, SCP(Q parallel,Q perpendicular) , only available by CV-SANS, indicated the presence of a polymer-enriched layer adsorbed to clay surface, which are responsible for large extensibility of NC gels over 1000% strain and large toughness exceeding 780 kPa.
采用对比变化小角中子散射（CV-SANS）研究了由聚合物链和无机粘土片层组成的高性能纳米复合聚合物水凝胶（NC凝胶）的变形机制。在高达λ = 9的各种拉伸比下获得了各向异性的小角中子散射函数，并将其分解为三个部分结构因子S(ij)(Q平行,Q垂直)。这里，下标i和j分别表示聚合物（P）或粘土（C），Q平行和Q垂直分别是沿拉伸方向和垂直于拉伸方向的散射矢量的大小。SCC(Q平行,Q垂直)和S_{PP}(Q平行,Q垂直)表明，粘土片层的取向在λ约为3时达到饱和，而聚合物链的拉伸通过进一步拉伸继续进行。另一方面，只有通过CV-SANS才能得到的SCP(Q平行,Q垂直)表明，存在吸附在粘土表面的富含聚合物的层，这是NC凝胶在超过1000%应变下具有大拉伸性和超过780 kPa的大韧性的原因。
