In this research,the wetting behavior of nonionic surfactant Triton X-100 on wheat leaf sunfaces at different developmental stages has been investigated based on the surface free energy,contact angle,adhesion tension,and liquid-solid interfacial tension.The results show that the contact angle remains constant with low adsorption at the liquid-air (ΓLv) and liquid-solid (Γ'SL) interfaces at low concentration,and the wetting state is in the Cassie-Baxter state.On increasing the concentration,the contact angle decreases sharply and the ratio of Γ'SL/FLv becomes more than 1.Meanwhile,the droplet overcomes the pinning effect to displace the air among three-dimensional wax layers and is in the Wenzel state.When the concentration becomes over critical micelle concentration (CMC),a saturated adsorption film forms at the interfaces,and the hemiwicking process occurs among micro/nano structures because of the capillary effect,then the contact angle remains constant.%选择不同生长期小麦叶片,利用座滴法研究了非离子表面活性剂Triton X-1 00在小麦叶片表面接触角,考察浓度对接触角、粘附张力、固-液界面张力及润湿状态的影响.研究表明,在低浓度下,表面活性剂分子在气-液界面吸附量(ΓLV)和固-液界面吸附量(Γ'SL)相似,但吸附量较少形成了不饱和吸附层,接触角保持不变,其润湿状态为Cassie-Baxter状态;当浓度进一步增加,液滴突破叶片表面三维立体结构中存在的钉扎效应,取代空气层而处于Wenzel状态,接触角陡降,同时Γ'SL/ΓLV远大于1;当浓度超过临界胶束浓度(CMC)时,表面活性剂分子在气-液界面和固-液界面形成饱和吸附层,并产生毛细管效应,使溶液在小麦叶片三维立体结构中产生半渗透过程,此时接触角保持不变.
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