Adsorption‐mediated nonlinearity of critical cracking thickness in drying nanoparticle?polymer suspensions
Adsorption‐mediated nonlinearity of critical cracking thickness in drying nanoparticle?polymer suspensions
复制标题
干燥纳米粒子聚合物悬浮液中吸附介导的临界裂纹厚度的非线性
DOI：
10.1002/aic.17229
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发表时间：
2021
期刊：
影响因子：
3.7
通讯作者：
Yamamura Masato
中科院分区：
文献类型：
--
作者：
Ichimaru Hiroaki;Taguchi Tetsushi;炭崎晴香，上田正人，池田勝彦，猿渡ちひろ;田川賢太朗，新里恵多，魏弘之，宮岡裕樹，市川貴之;Yamamura Masato
我们研究了含有水溶性聚合物添加剂的干态胶体TiO 2悬浮液的临界开裂厚度，超过该临界开裂厚度裂纹会自发扩展。与常见的观察结果相反，临界开裂厚度随着悬浮液中聚合物添加剂的浓度增加而以非线性、逐步的方式增加。当聚合物含量增加到某一阈值以上时，临界厚度发散。我们证明，第一和第二临界开裂厚度增量是由于聚合物吸附和随后的吸附聚合物链的构象的转变，分别发病。不同粒径下相对于标准化聚合物吸附量的临界厚度曲线收敛于一条主曲线。这些结果说明了非平凡的蒸发过程中，聚合物添加剂的各种作用延迟开裂成较厚的膜。
We examine the critical cracking thicknesses of as‐dried colloidal TiO2suspensions containing water‐soluble polymeric additives, above which cracks spontaneously propagate. In contrast to common observations, the critical cracking thickness increases in a nonlinear, stepwise manner as increasing the concentration of the polymeric additive in the suspension. The critical thickness diverges when the polymer content increases above a certain threshold. We demonstrate that the first and second critical cracking thickness increments are attributable to the onset of polymer adsorption and a subsequent transition in the conformations of the adsorbing polymer chains, respectively. The critical thickness profiles with respect to normalized polymer adsorption amounts at different particle diameters converged into a single master curve. These results illustrate nontrivial evaporation processes in which the various roles of polymeric additives delay cracking into thicker films.