TY - JOUR
T1 - Dual Light- and pH-Responsive Composite of Polyazo-Derivative Grafted Cellulose Nanocrystals
AU - Liu, Xiaohong
AU - Li, Ming
AU - Zheng, Xuemei
AU - Retulainen, Elias
AU - Fu, Shiyu
N1 - Funding Information:
The authors also thank Puneet Kumar Singh, one of the participants in this study, for his assistance with the whole process of this experiment. This research was funded by [State Key Laboratory of Pulp and Paper Engineering] [2016PY01], [the Science and Technology Program of Guangzhou] [201704020038], [the Natural Science Foundation of Guangdong Province China] [2014A030311030], [the National Natural Science Foundation of China] [31570569].
Publisher Copyright:
© 2018 by the authors.
Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 2018/9/14
Y1 - 2018/9/14
N2 - As a type of functional group, azo-derivatives are commonly used to synthesize responsive materials. Cellulose nanocrystals (CNCs), prepared by acid hydrolysis of cotton, were dewatered and reacted with 2-bromoisobuturyl bromide to form a macro-initiator, which grafted 6-[4-(4-methoxyphenyl-azo) phenoxy] hexyl methacrylate (MMAZO) via atom transfer radical polymerization. The successful grafting was supported by Fourier transform infrared spectroscopy (FT-IR) and Solid magnetic resonance carbon spectrum (MAS 13C-NMR). The morphology and surface composition of the poly{6-[4-(4-methoxyphenylazo) phenoxy] hexyl methacrylate} (PMMAZO)-grafted CNCs were confirmed with Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The grafting rate on the macro-initiator of CNCs was over 870%, and the polydispersities of branched polymers were narrow. The crystal structure of CNCs did not change after grafting, as determined by X-ray diffraction (XRD). The polymer PMMAZO improved the thermal stability of cellulose nanocrystals, as shown by thermogravimetry analysis (TGA). Then the PMMAZO-grafted CNCs were mixed with polyurethane and casted to form a composite film. The film showed a significant light and pH response, which may be suitable for visual acid-alkali measurement and reversible optical storage.
AB - As a type of functional group, azo-derivatives are commonly used to synthesize responsive materials. Cellulose nanocrystals (CNCs), prepared by acid hydrolysis of cotton, were dewatered and reacted with 2-bromoisobuturyl bromide to form a macro-initiator, which grafted 6-[4-(4-methoxyphenyl-azo) phenoxy] hexyl methacrylate (MMAZO) via atom transfer radical polymerization. The successful grafting was supported by Fourier transform infrared spectroscopy (FT-IR) and Solid magnetic resonance carbon spectrum (MAS 13C-NMR). The morphology and surface composition of the poly{6-[4-(4-methoxyphenylazo) phenoxy] hexyl methacrylate} (PMMAZO)-grafted CNCs were confirmed with Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The grafting rate on the macro-initiator of CNCs was over 870%, and the polydispersities of branched polymers were narrow. The crystal structure of CNCs did not change after grafting, as determined by X-ray diffraction (XRD). The polymer PMMAZO improved the thermal stability of cellulose nanocrystals, as shown by thermogravimetry analysis (TGA). Then the PMMAZO-grafted CNCs were mixed with polyurethane and casted to form a composite film. The film showed a significant light and pH response, which may be suitable for visual acid-alkali measurement and reversible optical storage.
KW - cellulose nanocrystals
KW - azo-derivatives
KW - atom transfer radical polymerization
KW - light- and pH responsive
UR - http://www.scopus.com/inward/record.url?scp=85053407079&partnerID=8YFLogxK
U2 - 10.3390/ma11091725
DO - 10.3390/ma11091725
M3 - Article
SN - 1996-1944
VL - 11
JO - Materials
JF - Materials
IS - 9
M1 - 1725
ER -