Preparation And Nanopattern Application Of Self-Assembled Monolayers Of Dopamine Derivatives

Since proposed from last century, the study of soft matter has become more and more popular. Nowadays, Polymer, as a typical kind of soft matter, has been paid much attention. To research the control of the self-organization of polymer, people has developed some ways, like spin coating, nanoimprint. For these methods, substrate’s and template’s surface properties show great effect to polymer self-organization. Self-assembled monolayers(SAMs) are the most common means to regulate the substrate surface properties. So far, depending on the substrates to be modified, different anchoring chemistries have been established, like silanes, thiols, and phosphonates. However, these anchors are limited to specific substrates. For instance, the silane-terminated molecules are suitable for silicon and glass, and alkanethiols are limited to noble metals. Considering the restrictions, it is desirable to develop a universal anchor for SAMs to modify a broad range of material surfaces. Recently, dopamine(catechol), as a novel biomimetic adhesive, came into spotlight gradually. The dopamine-based surface modification was reported with some advantages, such as, this kind of adhesive can adhere on a wide variety of substrates, the adhesion can keep on working in wet condition, and the reaction can achieved at room temperature without further heating. Based on these features, in this paper, we investigate the formation of dopamine derivatives self-assembled monolayers(SAMs), the surface properties’ control and nanoimprint application of these functional dopamine self-assembled monolayers(SAMs).The researches and results are summarized as following:(1) Three functional dopamine derivatives with different end-groups, including n-capryloyldopamine(CD), n-(3,4-dihydroxy-phenethyl)-phenylbutyamide(PBD), n-(4,5-dihydroxy-2-nitro-phenethyl)-perfluorocaprylamide(PFCND), were designed and synthesized. With a single organic solution immersion method, we can form dopamine self-assembled monolayers(SAMs) successfully. The monolayer was characterized and verified with different methods, and we still build a new model for the arrangement of dopamine molecules in the SAMs.(2) After modification, the functional dopamine self-assembled monolayers(SAMs) were utilized to control the wettability of silicon substrate surface and the surface work function of indium-tin oxide(ITO) substrate surface.(3) Combining with the electron beam lithography(EBL), the self-assembly of dopamine derivatives were used to prepare functional binary nanopatterned template, and the template was successfully applied to control the self-organization of conjugated polymer.