Department of Mechanical Engineering, Inha University, 100 Inha-ro, Michuhol-gu, Incheon 22212, Republic of Korea.
Department of Mechanical Engineering, Inha University, 100 Inha-ro, Michuhol-gu, Incheon 22212, Republic of Korea.
J Colloid Interface Sci. 2019 Nov 15;556:503-513. doi: 10.1016/j.jcis.2019.08.081. Epub 2019 Aug 23.
Diverse surface/bulk treatments have been introduced to overcome the interfacial limitations of pristine (or untreated) PDMS, thus extending the possible applications of PDMS in micro/nano device development. Despite of extensive efforts, the temporal wetting change of PDMS induced by surface/bulk treatments still remains incompletely understood. We prepared 3 kinds of physicochemically treated PDMS blocks using widely used surface/bulk treatments-3D interconnected pore network formation, biocompatible surfactant (i.e., Silwet L-77) addition, and combination of both. Their wetting nature was characterized by measuring the time profile of water contact angle. A 3D interconnected pore network formation produced a time-invariant decrease in PDMS wettability; a surfactant addition increased the PDMS wettability in a time-variant way; a combination of pore network formation and surfactant addition had a combined effect. The measurement led to the successful development of a model for predicting the temporal wetting change in PDMS caused by variances in pore size and surfactant concentration. The accuracy of our model was verified by comparing experimental results with model predictions. This model will result in better understanding of polymer interface.
已经引入了多种表面/体处理方法来克服原始（或未处理）PDMS 的界面限制，从而扩展了 PDMS 在微/纳器件开发中的可能应用。尽管已经做了广泛的努力，但表面/体处理引起的 PDMS 的瞬时润湿变化仍然不完全清楚。我们使用广泛使用的表面/体处理方法——三维互连孔网络形成、生物相容性表面活性剂（即 Silwet L-77）添加以及两者的组合，制备了 3 种物理化学处理的 PDMS 块。通过测量水接触角的时间曲线来表征它们的润湿性质。三维互连孔网络形成导致 PDMS 润湿性的时间不变性降低；表面活性剂的添加以时变的方式增加了 PDMS 的润湿性；孔网络形成和表面活性剂添加的组合具有协同作用。该测量成功地开发了一种预测由于孔径和表面活性剂浓度变化引起的 PDMS 瞬时润湿变化的模型。通过将实验结果与模型预测进行比较，验证了我们模型的准确性。该模型将有助于更好地理解聚合物界面。
