Yao Yijun, Zhu Junxin, Shen Yanqin, Wu Hailiang
School of Textile Science and Engineering, Xi'an Polytechnic University, Xi'an 710048, Shaanxi, China.
Key Laboratory of Functional Textile Material and Product, Xi'an Polytechnic University, Ministry of Education, Xi'an 710048, Shaanxi, China.
ACS Appl Mater Interfaces. 2021 Oct 27;13(42):50338-50349. doi: 10.1021/acsami.1c14305. Epub 2021 Oct 12.
Herein, we prepared a dual-emitting cellulose film with pH response, which offers high transparency, good flexibility, and intense thermal stability. The color of the fluorescent film that changes from green to blue-green to cyan was achieved by covalently attaching organic dye fluorescein isothiocyanate (FITC), inorganic pigment NH-CaAlO:Eu,Dy (NH-CAO), and organic-inorganic fluorescence species onto hydroxypropyl methylcellulose (HMPC) chains, respectively. Benefiting from the "anchoring" and "dilution" effects of the HMPC skeleton, HPMC-FITC and HPMC@NH-CAO fluorescent solutions and solid-state films emit green and blue-green fluorescence at 535 and 480 nm, respectively. The obtained pH-responsive cellulose-based dual-emitting film can continuously emit cyan light at the two emission peaks of 480 and 535 nm for a long time and exhibits strong fluorescence intensity under exceedingly alkaline conditions. Moreover, the HPMC-based fluorescent solution coated on glass and fabric substrate shows strong fluorescence under 365 nm UV light stimulation. Compared with the existing cellulose-based fluorescent films, this work expands the emission wavelength range of cellulose-based fluorescent films and prolongs the luminescent time of environment-responsive fluorescent films. This provides a new way to prepare intelligent color-changing fabric-coating materials and sensitive pH sensors based on biomass.
在此，我们制备了一种具有pH响应的双发射纤维素薄膜，其具有高透明度、良好的柔韧性和强烈的热稳定性。通过将有机染料异硫氰酸荧光素（FITC）、无机颜料NH-CaAlO:Eu,Dy（NH-CAO）和有机-无机荧光物种分别共价连接到羟丙基甲基纤维素（HMPC）链上，实现了荧光薄膜颜色从绿色到蓝绿色再到青色的变化。受益于HMPC骨架的“锚定”和“稀释”效应，HPMC-FITC和HPMC@NH-CAO荧光溶液及固态薄膜分别在535和480 nm处发射绿色和蓝绿色荧光。所制备的基于pH响应的纤维素基双发射薄膜能够在480和535 nm的两个发射峰处长时间持续发射青色光，并且在极强碱性条件下表现出较强的荧光强度。此外，涂覆在玻璃和织物基材上的基于HPMC的荧光溶液在365 nm紫外光刺激下显示出强烈的荧光。与现有的基于纤维素的荧光薄膜相比，这项工作拓宽了基于纤维素的荧光薄膜的发射波长范围，并延长了环境响应型荧光薄膜的发光时间。这为制备基于生物质的智能变色织物涂层材料和灵敏pH传感器提供了一种新方法。
