College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China; National Demonstration Center for Experimental Light Chemistry Engineering Education, Shaanxi University of Science and Technology, Xi'an 710021, China.
College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China; National Demonstration Center for Experimental Light Chemistry Engineering Education, Shaanxi University of Science and Technology, Xi'an 710021, China.
Int J Biol Macromol. 2023 Sep 30;249:126062. doi: 10.1016/j.ijbiomac.2023.126062. Epub 2023 Jul 29.
The development of environmental-friendly self-healing nanocomposites has attracted much attention. In this paper, the light-activated cellulose nanocrystals/ fluorinated polyacrylate-based waterborne coating based on the reversible cycloaddition reaction of the coumarin groups was prepared via Pickering emulsion polymerization. The cellulose nanocrystals (CNCs) modified by the PDMAEMA-b-PGMA-b-P(HFBA-co-VBMC) copolymer were studied via FT-IR and TGA. In addition, the dispersity and interface behavior of CNCs before and after modification were investigated by DLS and interfacial tension measurements. Afterwards, we focused on the influence of modified CNCs, PDMAEMA-g-CNC-g- P(HFBA-co-VBMC) (MCNC) dosage on the Pickering emulsion, emulsion polymerization and properties of latex film. The droplet diameter of Pickering emulsion gradually reduced with the increase of MCNC dosage. The MCNC dosage for the minimum average size and optimum stability of latex particles was 1.0 wt%. Moreover, the latex film comprising 1.0 wt% MCNC presented not only high tensile stress (6.0 MPa), large elongation at break (567.70 %) and superior oil/water repellency but also excellent self-healing properties. The outstanding self-healing capability of latex film was attributed to the reversible light-activated dimerization of coumarin groups. The preparation method for the advanced performance waterborne cellulose nanocrystals/fluorinated polyacrylate will provide valuable guidance for the development of versatile materials.
环保型自修复纳米复合材料的发展引起了广泛关注。本文通过 Pickering 乳液聚合，制备了基于香豆素基团可逆环加成反应的光激活纤维素纳米晶/含氟聚丙烯酸酯基水基涂料。通过傅里叶变换红外光谱（FT-IR）和热重分析（TGA）研究了由 PDMAEMA-b-PGMA-b-P（HFBA-co-VBMC）共聚物修饰的纤维素纳米晶（CNCs）。此外，通过动态光散射（DLS）和界面张力测量研究了修饰前后 CNCs 的分散性和界面行为。之后，我们重点研究了改性 CNCs（PDMAEMA-g-CNC-g-P（HFBA-co-VBMC）（MCNC））用量对 Pickering 乳液、乳液聚合和乳胶膜性能的影响。Pickering 乳液的液滴直径随 MCNC 用量的增加而逐渐减小。MCNC 用量为 1.0wt%时，乳胶粒子的平均粒径最小，稳定性最佳。此外，包含 1.0wt%MCNC 的乳胶膜不仅表现出高拉伸应力（6.0MPa）、大断裂伸长率（567.70%）和优异的耐油/水性能，而且还具有出色的自修复性能。乳胶膜优异的自修复性能归因于香豆素基团的可逆光激活二聚化。先进性能水基纤维素纳米晶/含氟聚丙烯酸酯的制备方法将为多功能材料的开发提供有价值的指导。
