Multiscale Insights into Tailored Structural Stabilization of Collagen Fibers by Dual-Functionalized Two-Dimensional ZrP Nanoplatelets

The exploration of eco-friendly and sustainable processing has become a central focus of the manufacture of multifunctional eco-leather in the leather industry. Understanding the structural stabilization of type I collagen fibers by active substances is a key issue for the conversion of collagen fibers into a leather matrix. Here, we proposed an effective strategy for tailored structural stabilization of collagen fibers by dual-functionalized two-dimensional zirconium phosphate nanoplatelets (ZrP NPs) to optimize a tannic acid (TA)-based wet-white tanning system toward multifunctional eco-leather manufacture. The results indicated that dual-functionalized ZrP NPs were successfully achieved by surface-grafting of building blocks (i.e., gallic acid and acrylic acid) onto the surfaces of ZrP NPs. Through examining the influence of dual-functionalized ZrP NPs and final pH value on tanning efficiency, we established a wet-white tanning system based on 10 wt % TA and 3 wt % dual-functionalized ZrP NPs at a final pH of 3.5. Moreover, hydrogen-bonding and electrostatic interactions between the dual-functionalized ZrP NPs and collagen fibers stabilized the microstructures of the collagen fibers, enabling hierarchical incorporation of the dual-functionalized NPs with the eco-leather matrix. Besides, the dual-functionalized NPs exhibited not only effective penetration into the microstructures of collagen fibers but also sufficient binding onto the collagen fibers without altering native D -periodic banding patterns of collagen fibrils. We anticipate these findings will offer multiscale insights into tailored structural stabilization of type I collagen fibers by two-dimensional nanomaterials for rational design and optimization of a feasible wet-white tanning system toward multifunctional eco-leather manufacture.