409240 Fluorine-Free Superhydrophobic Film Based on Polybenzoxazine

Monday, November 9, 2015: 4:39 PM
Salon I (Salt Lake Marriott Downtown at City Creek)
Wenfei Zhang, East China University of Science and Technology, Shanghai, China and Zhong Xin, State Key Laboratory of Chemical Engineering, East China University of Science and Technology, School of Chemical Engineering, Shanghai, China

Bioinspired superhydrophobic surfaces which possess the merit of a water contact angle (CA) larger than 150o have numerous applications such as in self-cleaning, oil/water separation and liquid transportation. As is well known, chemical modification of a rough surface is rewarding to superhydrophobicity. Conventionally, the modification agent is a fluorine-containing low surface free energy material such as perfluorocarbon or fluoroalkylsilane. And roughening of a surface involves sophisticated processes such as etching and templating. Therefore, it has been desired to prepare superhydrophobic films by a cost-efficient and an easier process. As a new type of low surface free energy material, polybenzoxazine (PBZ) is promising for a superhydrophobic film due to its cross-linking structure, low water absorption and low cost. In our previous work, a fluorine-containing and fluorine-free silane-functionalized PBZ film with surface free energy of 15.5 mJ/m2 and 14.91 mJ/m2 has been synthesized respectively. (J. Liu, Z. Xin et al, Langmuir, 2013; L. Qu and Z. Xin, Langmuir, 2011)

In this paper, two important properties are combined: the low surface free energy property of polybenzoxazine (PBZ) and the photo-induced superhydrophilicity property of TiO2. As a result, a multifunctional superhydrophobic PBZ/TiO2 surface with a water contact angle of ~160 o and sliding angle less than 2 o is prepared by using spin coating method without any fluorine-containing surface modification agents. The as-prepared superhydrophobic film has good adhesion to substrate, and its superhydrophobicity is stable even after heat treatment at 300 oC and environmentally durable for more than half a year. When the content of TiO2 is increased, the consequent nanocomposite film exhibits hydrophobicity-superhydrophilicity transitions with a variation of around 120o in water CA upon ultraviolet (UV) exposure-heat treatment cycles.

Extended Abstract: File Not Uploaded
See more of this Session: Sustainable and Green Product Design
See more of this Group/Topical: Process Development Division