Preparation and properties of mechanically induced double crosslinked anisotropic cellulose hydrogel
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摘要: 为改善传统纤维素水凝胶材料柔软易碎的性质，拓宽其应用领域，开发出具有优异力学性能的纤维素水凝胶，在LiOH-尿素体系中溶解纤维素后，先加入环氧氯丙烷制备出具有松散化学交联网络结构的纤维素水凝胶，再通过在酸溶液去除碱-尿素包裹体系后形成物理交联，获得具有初步取向的双交联纤维素水凝胶；在此基础上，沿长度方向调控机械力拉伸固定双网络结构水凝胶，获得不同力学性能的各向异性纤维素水凝胶。研究表明：经拉伸后水凝胶最大拉伸强度可达2.96 MPa，纤维素水凝胶在偏振光下出现彩色偏光现象，表现出典型的光学各向异性；通过该方法可构建出具有高强度、光学各向异性的纤维素水凝胶，该类水凝胶在智能软物质等领域具有良好的应用前景。Abstract: In order to improve the softness and fragility of traditional cellulose hydrogel materials, broaden its application area and develop cellulose hydrogels with excellent mechanical properties, the cellulose hydrogel with loose chemical crosslinking network was prepared by adding epichlorohydrin into cellulose dissolved in LiOH-urea aqueous solution. Then the alkali-urea inclusion complex in the acid solution was removed to introduce physical crosslinking. The dual-crosslinking cellulose hydrogel with temporary orientation was obtained. On this basis, the researcher regulated mechanical force to stretch and fix the hydrogel with double network structure along the length direction to obtain anisotropic cellulose hydrogels with different mechanical properties. Research shows, the maximum tensile strength of cellulose hydrogels can reach 2.96 MPa after stretching, and the cellulose hydrogel exhibits color polarization phenomenon under polarized light, showing typical optical anisotropy. This method can construct cellulose hydrogels with high strength and optical anisotropy. This type of hydrogels has good application prospects in the fields of intelligent soft matter and others.
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Key words:
- cellulose /
- hydrogel /
- anisotropy /
- double crosslinking /
- mechanical force orientation
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图 1 化学交联纤维素水凝胶(CCH)和双交联纤维素水凝胶(DCH)制备机制
Figure 1. Preparation mechanism of chemically cross-linked cellulose hydrogel (CCH) and double cross-linked cellulose hydrogel (DCH)
x%DCH(x=50, 70, 100)—DCH with tensile ratio of x%
图 2 不同条件下纤维素水凝胶的SEM图像
Figure 2. SEM images of cellulose hydrogels under different conditions
图 4 纤维素水凝胶的拉伸应力-应变曲线 (a) 和70%DCH的循环拉伸应力-应变曲线 (b)
Figure 4. Tensile stress-strain curves of cellulose hydrogel (a) and 70%DCH circulatory stretch stress-strain curves (b)
图 6 CCH与DCH在交叉偏振片之间的照片
Figure 6. Photographs of CCH and DCH between crossed polarizers
表 1 在不同条件下制备的水凝胶的力学性能和含水量
Table 1. Mechanical properties and water contents of hydrogels prepared under different conditions
Sample Water
content/%Tensile
strength/MPaElongation/
%Tensile
modulus/MPaFracture
toughness/(J·m−2)CCH 98.0 0.04±0.02 39±2.5 0.03±0.01 0.72±0.23 DCH 88.9 1.73±0.52 118±1.3 0.59±0.17 95.62±10.21 50%DCH 90.3 2.01±0.78 83±9.0 0.97±0.26 71.38±9.56 70%DCH 91.2 2.68±0.73 64±5.9 2.13±0.19 86.00±9.72 100%DCH 89.2 2.96±0.50 43±6.4 4.09±0.25 101.74±10.64 Note: x%DCH—DCH with stretching ratio of x. 
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[1] PEPPAS N A, HILT J Z, KHADEHOSSEINI A, et al. Hydrogels in biology and medicine: From molecular principles to bionanotechnology[J]. Advanced Materials,2006,18(11):1345-1360. doi: 10.1002/adma.200501612 [2] LEE K Y, MOONEY D J. Hydrogels for tissue engineering[J]. Chemical Reviews,2001,101(7):1869-1880. doi: 10.1021/cr000108x [3] TAYLOR D L, MARC I H P. Self-healing hydrogels[J]. Advanced Materials,2016,28(41):9060-9093. doi: 10.1002/adma.201601613 [4] KIM H N, HWANG N S, KIM M S, et al. Nanotopography-guided tissue engineering and regenerative medicine[J]. Advanced Drug Delivery Reviews,2013,65(4):536-558. [5] 黄进. 生物基聚多糖纳米晶: 化学及应用[M]. 北京: 化学工业出版社, 2015: 7.HUANG Jin. Bio-based polysaccharide nanocrystals: Chemistry and application[M]. Beijing: Chemical Industry Press, 2015: 7. [6] ELLIOTT G F, ROME E M. Liquid-crystalline aspects of muscle fibers[J]. Molecular Crystals and Liquid Crystals,1969,8(1):215-218. [7] 杨蕊, 曹清华, 梅长彤, 等. 高孔隙率三维结构木材构建功能复合材料的研究进展[J]. 复合材料学报, 2020, 37(8):1796-1804.YANG Rui, CAO Qinghua, MEI Changtong, et al. Research progress of functional composite materials con-structed from high porosity three-dimensional structural wood[J]. Acta Materiae Compositae Sinica,2020,37(8):1796-1804(in Chinese). [8] LIU M, ISHIDA Y, EBINA Y, et al. An anisotropic hydrogel with electrostatic repulsion between cofacially aligned nanosheets[J]. Nature,2015,517(7532):68-72. doi: 10.1038/nature14060 [9] MORALES D, BHARTI B, DICKEY M D, et al. Bending of responsive hydrogel sheets guided by field-assembled mi-croparticle endoskeleton structures[J]. Small,2016,12(7):2283-2290. [10] SHIKINAKA K, KOIZUMI Y, SHIGEHARA K. Mechanical/optical behaviors of imogolite hydrogels depending on their compositions and oriented structures[J]. Journal of Applied Polymer Science,2015,132(12):675-691. [11] DECILLE S, SAIZ E, NALLA R K, et al. Freezing as a path to build complex composites[J]. Science,2006,311(5760):515-518. doi: 10.1126/science.1120937 [12] WEGST U G, SCHECTER M, DONIUS A E, et al. Bio-materials by freeze casting[J]. Philosophical Transactions of the Royal Society B-biological Sciences,2010,368(1917):2099-2121. [13] 李泽, 何文, 强瀚, 等. 定向重组竹纤维素纤维/酚醛树脂复合材料的制备及其性能[J]. 复合材料学报, 2021, 38(10):3228-3236.LI Ze, HE Wen, QIANG Han, et al. Preparation and properties of directionally reconstituted bamboo cellulose fiber/phenolic resin composites[J]. Acta Materiae Compositae Sinica,2021,38(10):3228-3236(in Chinese). [14] WEGSTU G, BAI H, SAIZ E, et al. Bioinspired structural materials[J]. Nature Materials,2015,14(1):23-36. doi: 10.1038/nmat4089 [15] BAI H, POLINI A, DELATTRE B, et al. Thermoresponsive composite hydrogels with aligned microporous structure by ice-templated assembly[J]. Chemistry of Materials,2013,25(22):4551-4556. doi: 10.1021/cm4025827 [16] TAMESUE S, OHTANI M, YAMADA K, et al. Linear versus dendritic molecular binders for hydrogel network formation with clay nanosheets: Studies with ABA triblock copolyethers carrying guanidinium ion pendants[J]. Journal of the American Chemical Society,2013,135(41):15650-15655. doi: 10.1021/ja408547g [17] GONG J P, KATSUYAMA Y, KUROKAWA T, et al. Double-network hydrogels with extremely high mechanical strength[J]. Advanced Materials,2020,15(14):1155-1158. [18] ZHOU J, DU X W, GAO Y, et al. Aromatic-aromatic interactions enhance interfiber contacts for enzymatic formation of a spontaneously aligned supramolecular hydrogel[J]. Journal of the American Chemical Society,2014,136(8):2970-2973. doi: 10.1021/ja4127399 [19] LI I C, HARTGERINK J D. Covalent capture of aligned self-assembling nanofibers[J]. Journal of the American Chemical Society,2017,139(23):8044-8050. doi: 10.1021/jacs.7b04655 [20] ZHAO X H. Multi-scale multi-mechanism design of tough hydrogels: Building dissipation into stretchy networks[J]. Soft Matter,2014,10(5):672-687. doi: 10.1039/C3SM52272E [21] PEI Y, YE D D, ZHAO Q, et al. Effectively promoting wound healing with cellulose/gelatin sponges constructed directly from a cellulose solution[J]. Journal of Materials Chemistry B,2015,3(38):7518-7528. [22] XU D F, FAN L, GAO L F, et al. Micro-nanostructured polyaniline assembled in cellulose matrix via interfacial polymerization for applications in nerve regeneration[J]. ACS Applied Materials & Interfaces,2016,8(27):17090-17097. [23] ZHAO D, HUANG J C, ZHONG Y, et al. High-strength and high-toughness double-cross-linked cellulose hydrogels: A new strategy using sequential chemical and physical cross-linking[J]. Advanced Functional Materials,2016,26(34):6279-6287. doi: 10.1002/adfm.201601645 [24] ZHU M W, SONG J W, LI T, et al. Highly anisotropic, highly transparent wood composites[J]. Advanced Materials,2016,28(26):5181-5187. doi: 10.1002/adma.201600427 [25] ZHU M W, WANG Y L, ZHU S Z, et al. Anisotropic, transparent films with aligned cellulose nanofibers[J]. Advanced Materials,2017,29(21):1606284. [26] TSENG P, NAPIER B, ZHAO S, et al. Directed assembly of bio-inspired hierarchical materials with controlled nano-fibrillar architectures[J]. Nature Nanotechnology,2017,12(5):474-480. doi: 10.1038/nnano.2017.4 [27] CAI J, ZHANG L N. Rapid dissolution of cellulose in LiOH/urea and NaOH/urea aqueous solutions[J]. Macromolecular Bioscience,2005,5(130):539-548. [28] YE D D, YANG P C, LEI X J, et al. Robust anisotropic cellulose hydrogels fabricated via strong self-aggregation forces for cardiomyocytes unidirectional growth[J]. Chemistry of Materials,2018,30:5175-5183. doi: 10.1021/acs.chemmater.8b01799 -
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