A highly effective way is found to incorporate dopamine (DA) containing catechol groups into waterborne polyurethane backbone. Firstly, prepolymer polyurethane (PPU) containing sulfydryl were created through stepwise polymerization in which isophorone diisocyanate (IPDI) was as hard segment, polyethylene glycol (PEG)(Mn=600) was as soft segment, dimethylolpropionic acid (DMPA) was as hydrophilic monomer and monothioglycerol (MON) was as chain extender. Then a series of catechol-based waterborne polyurethanes (MON-PPU-DOMA) was obtained by introducing methacrylamide dopamine (DOMA) into polyurethane backbone via thiol-ene click chemistry. FT-IR, ¹H-NMR and UV–vis spectra showed that DOMA was successfully incorporated into polyurethane backbone. TG and mechanical properties testing results indicated that the heat resistance and tensile strength of MON-PPU-DOMA films were obviously improved. Moreover, MON-PPU-DOMA/Fe³⁺ complex was obtained by MON-PPU-DOMA with Fe³⁺ triggered via adjusting pH and their color and state change was apparent, which also made it possible for MON-PPU-DOMA/Fe³⁺ to become an injection adhesion material. MON-PPU-DOMA was used to bonding different substrates. The results showed that the lap shear strength of MON-PPU-DOMA to iron sheet was 3.23 MPa, which was obviously bigger than that of MON-PPU without DOMA. The introduction of DOMA can significantly improve adhesive ability of polyurethane. Because it is difficult to dissolve in DMF, MON-PPU-DOMA emulsion has the potential of being an environmentally friendly coating on the surface of iron substrates.

发现一种高效方法是将含有邻苯二酚基团的多巴胺（DA）掺入水性聚氨酯主链中。首先，以异佛尔酮二异氰酸酯（IPDI）为硬链段，聚乙二醇（PEG）（Mn = 600）为软链段，二羟甲基丙酸（DMPA）为亲水性单体，通过逐步聚合制备含巯基的预聚物聚氨酯（PPU）。一硫代甘油（MON）作为扩链剂。然后，通过硫醇-烯点击化学将甲基丙烯酰胺多巴胺（DOMA）引入聚氨酯主链中，得到了一系列基于邻苯二酚的水性聚氨酯（MON-PPU-DOMA）。FT-IR，¹H-NMR和UV-vis光谱表明，DOMA已成功掺入聚氨酯骨架中。TG和力学性能测试结果表明，MON-PPU-DOMA薄膜的耐热性和拉伸强度明显提高。此外，MON-PPU-DOMA通过调节pH触发Fe ³⁺获得了MON-PPU-DOMA / Fe ³⁺络合物，其颜色和状态变化明显，这也使得MON-PPU-DOMA / Fe成为可能。³⁺成为注射粘合材料。MON-PPU-DOMA用于粘合不同的基板。结果表明，MON-PPU-DOMA对铁片的搭接剪切强度为3.23 MPa，明显大于无DOMA的MON-PPU。DOMA的引入可以显着提高聚氨酯的粘合能力。由于难溶于DMF，MON-PPU-DOMA乳液具有在铁基质表面上形成环保涂层的潜力。