Catechol‐containing waterborne polyurethane adhesive inspired by mussel proteins

Abstract

A series of waterborne polyurethane (PDMAPU) containing catechol group were prepared by double-bond random copolymerization of terminated double bond polyurethane prepolymer with modified acrylamido dopamine under thermal initiation. This kind of mussel-like waterborne polyurethane adhesive is inspired by marine mussel, as well as it is environment-friendly and used in bonding of leather. FTIR and 1 H NMR proved the successful introduction of catechol group into polyurethane matrix. Oxidative cross-linking between catechol unit and molecular chain in PDMAPU structure, the thermal stability and crystallization ability of PDMAPU was significantly improved. The increase of the particle size of PDMAPU emulsion showed that the introduction of catechol group changed the microstructure of polyurethane and enhanced the cross-linking degree. The water resistance of polyurethane emulsion was further improved. Compared with PU without catechol group, the peel strength of leather substrate adhered by PDMAPU emulsion increased from 0.42 to 1.93 MPa, which indicated that PDMAPU has better bonding properties with leather. The bidentate hydrogen bond formed with catechol group as the reaction sites is considered to be the key reason for the adhesion of mussel-like polyurethane adhesive to hydrophilic substrates. This work provides an alternative to prepare environment-friendly high performance adhesive for hydrophilic substrates.

Nylon 66 fibers coated with environmentally friendly dopamine‐modified adhesives and their interfacial adhesion with neoprene rubber

“…Firstly, GDML containing epoxy groups and catechol groups can react with the CONH, OH, and NH 2 groups in PA66. During the co‐vulcanization process, the highly reactive catechol groups in GDML are oxidized to form ortho‐quinone and di‐quinone structures, which can further crosslink with the amino groups in PA66 by Schiff base or Michael addition reactions 38 . Secondly, the epoxy group crosslinks with the ‐CONH‐ group to form a chemical bond at 150°C 39 .…”

Synthesis and characterization of hydroxyl-terminated polybutadiene modified low temperature adaptive self-matting waterborne polyurethane

“…Therefore, matt coatings are widely used on the surfaces of wood and furniture, leather accessories, automotive parts, aircra shells, electronic equipment shells, school and hospital wall surfaces and so on. 2,[7][8][9][10][11] With the global emphasis on environmental protection concepts, volatile organic solvent (VOC) emission standards are becoming more and more stringent. [12][13][14][15][16] Waterborne polyurethane (WPU) is a polyurethane resin with water as dispersion medium.…”

“…11 WPU not only has the advantages of traditional solvent-based polyurethane, such as excellent wear resistance and mechanical properties, but also is environmentally friendly, safe and reliable. 10,12,17 Therefore, it is widely used in coatings, adhesives, leather nishing agents and inks. 9,18,19 The principle of obtaining low gloss coating is that the rough surface has microscopic protrusions and depressions.…”

Strong Thermo-tolerant Silicone-Modified Waterborne Polyurethane/Polyimide Pressure-Sensitive Adhesive

“…The carbon-borane fluorinated polyesters (CFPETs) and polyurethanes (CFPUs) were characterized, and the results demonstrated that the modified polyurethanes had better features, including heat resistance and solvent resistance. Ren et al created a variety of aqueous polyurethanes containing catechol (PDMAPU) using heat-initiation copolymerization of modified acrylamide and polyurethane prepolymer. The oxidative cross-linking of catechol structures inside the PDMAPU structure increased the material’s thermal stability and crystallization potential.…”

“…Also, many studies have been done in an effort to increase the heat resistance of a waterborne polyurethane pressure sensitive adhesive. Fu et al 16 Ren et al 18 created a variety of aqueous polyurethanes containing catechol (PDMAPU) using heat-initiation copolymerization of modified acrylamide and polyurethane prepolymer. The oxidative cross-linking of catechol structures inside the PDMAPU structure increased the material's thermal stability and crystallization potential.…”