Franco Giuliana T, Figueiredo Luana, Otoni Caio G, Mattoso Luiz H C
Nanotechnology National Laboratory for Agriculture (LNNA), Embrapa Instrumentation, Rua XV de Novembro, 1452, São Carlos, São Paulo 13561-206, Brazil.
Department of Chemistry, Federal University of São Carlos (UFSCar), Rod. Washington Luís, km 235, São Carlos, São Paulo 13565-905, Brazil.
Langmuir. 2025 Jul 29;41(29):19409-19418. doi: 10.1021/acs.langmuir.5c01942. Epub 2025 Jul 14.
The design of functional multilayer materials relies on interfacial phenomena that govern component compatibility, structural integrity, and material performance. Self-supporting films were produced by combining casein and carboxymethylcellulose (CMC) bilayer. Here, we incorporated tannic acid (TA) and 1,2,3,4-butanetetracarboxylic acid (BTCA) into CMC layers as protein- and polysaccharide-crosslinking additives at varying ratios to tailor interfacial energy. The incorporation of TA led to interlayer adhesion, as evidenced by the increased force required for bilayer delamination. Additionally, the reduced moisture adsorption capacity upon TA addition supports the occurrence of interfacial crosslinking with the casein layer. ATR-FTIR measurements in the delaminated faces suggested a structural rearrangement that exposed nonpolar groups at the interfacial region. The vOCG approach predicted the contributions of secondary interactions, revealing that BTCA enhances electrostatic interactions, while TA contributes to nonpolar interactions. The theoretical work of adhesion was modulated according to the proportions of both crosslinkers. Understanding interfacial interactions helps design biobased materials with tailored properties and suitable performance as sustainable alternatives to plastics in the circular bioeconomy.
功能性多层材料的设计依赖于控制组分相容性、结构完整性和材料性能的界面现象。通过结合酪蛋白和羧甲基纤维素（CMC）双层制备了自支撑膜。在此，我们将单宁酸（TA）和1,2,3,4-丁烷四羧酸（BTCA）以不同比例作为蛋白质和多糖交联添加剂掺入CMC层中，以调整界面能。TA的掺入导致层间粘附，双层分层所需力的增加证明了这一点。此外，添加TA后水分吸附能力的降低支持了与酪蛋白层发生界面交联。在分层表面进行的ATR-FTIR测量表明发生了结构重排，使界面区域暴露了非极性基团。vOCG方法预测了二次相互作用的贡献，表明BTCA增强了静电相互作用，而TA有助于非极性相互作用。粘附的理论功根据两种交联剂的比例进行调节。了解界面相互作用有助于设计具有定制性能和合适性能的生物基材料，作为循环生物经济中塑料的可持续替代品。
