Cellulose-Based Hydrogels with Controllable Electrical and Mechanical Properties

2018 ◽  
Vol 232 (9-11) ◽  
pp. 1707-1716 ◽  
Author(s):  
Enwei Zhang ◽  
Jing Yang ◽  
Wei Liu

Abstract Electrically conductive cellulose-based hydrogels are prepared by a facile and environmentally friendly method, of which the electrical and mechanical properties can be easily controlled by varying the graphene loading. With an ultralow initial addition of graphene oxide (GO, 0.2 wt% versus the mass of cellulose), the resulting cellulose/reduced graphene oxide (CG0.2) hydrogel shows a significantly enhanced compressive modulus of 332.01 kPa, 54.8% higher than that of pure cellulose hydrogel. Further increasing the addition of GO to 2 wt% (versus the mass of cellulose), the electrical conductivity of the resultant CG2.0 hydrogel is as high as 7.3×10−3 S/m, 10,000-fold higher than that of pure cellulose hydrogel, and of which the mechanical properties are also enhanced. These cellulose-based hydrogels with controllable electrical and mechanical properties have a great potential for application in drug delivery and artificial muscle.

Soft Matter ◽  
2021 ◽  
Vol 17 (1) ◽  
pp. 68-82
Author(s):  
Qian Wu ◽  
Chun Liu ◽  
Longcheng Tang ◽  
Yue Yan ◽  
Huayu Qiu ◽  
...  

Reduced graphene oxide and silicone resin coated polyurethane foam composites with stable electrical conductivity and high flame retardancy.


Polymers ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1221
Author(s):  
Eun Bin Ko ◽  
Dong-Eun Lee ◽  
Keun-Byoung Yoon

The polymerizable reduced graphene oxide (mRGO) grafted styrene–acrylonitrile copolymer composites were prepared via free radical polymerization. The graphene oxide (GO) and reduced graphene oxide (rGO) was reacted with 3-(tri-methoxysilyl)propylmethacrylate (MPS) and used as monomer to graft styrene and acrylonitrile on its surface. The successful modification and reduction of GO was confirmed using Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analyzer (TGA), Raman and X-ray diffraction (XRD). The mRGO was prepared using chemical and solvothermal reduction methods. The effect of the reduction method on the composite properties and nanosheet distribution in the polymer matrix was studied. The thermal stability, electrical conductivity and morphology of nanocomposites were studied. The electrical conductivity of the obtained nanocomposite was very high at 0.7 S/m. This facile free radical polymerization provides a convenient route to achieve excellent dispersion and electrically conductive polymers.


2016 ◽  
Vol 4 (6) ◽  
pp. 1142-1149 ◽  
Author(s):  
K. S. U. Schirmer ◽  
D. Esrafilzadeh ◽  
B. C. Thompson ◽  
A. F. Quigley ◽  
R. M. I. Kapsa ◽  
...  

Wet–spun composite fibres from graphene and polypyrrole nanoparticles show appropriate mechanical properties, high electrical conductivity and good cytocompatibility.


Molecules ◽  
2019 ◽  
Vol 24 (23) ◽  
pp. 4247 ◽  
Author(s):  
Rita Petrucci ◽  
Isabella Chiarotto ◽  
Leonardo Mattiello ◽  
Daniele Passeri ◽  
Marco Rossi ◽  
...  

Natural methylxanthines, caffeine, theophylline and theobromine, are widespread biologically active alkaloids in human nutrition, found mainly in beverages (coffee, tea, cocoa, energy drinks, etc.). Their detection is thus of extreme importance, and many studies are devoted to this topic. During the last decade, graphene oxide (GO) and reduced graphene oxide (RGO) gained popularity as constituents of sensors (chemical, electrochemical and biosensors) for methylxanthines. The main advantages of GO and RGO with respect to graphene are the easiness and cheapness of synthesis, the notable higher solubility in polar solvents (water, among others), and the higher reactivity towards these targets (mainly due to – interactions); one of the main disadvantages is the lower electrical conductivity, especially when using them in electrochemical sensors. Nonetheless, their use in sensors is becoming more and more common, with the obtainment of very good results in terms of selectivity and sensitivity (up to 5.4 × 10−10 mol L−1 and 1.8 × 10−9 mol L−1 for caffeine and theophylline, respectively). Moreover, the ability of GO to protect DNA and RNA from enzymatic digestion renders it one of the best candidates for biosensors based on these nucleic acids. This is an up-to-date review of the use of GO and RGO in sensors.


2021 ◽  
Author(s):  
Zhanyu Jia ◽  
Guangyao Li ◽  
Juan Wang ◽  
shouhua Su ◽  
Jie Wen ◽  
...  

Conductivity, self-healing and moderate mechanical properties are necessary for multifunctional hydrogels which have great potential in health-monitor sensor application. However, the combination of electrical conductivity, self-healing and good mechanical properties...


2021 ◽  
pp. 004051752199547
Author(s):  
Min Hou ◽  
Xinghua Hong ◽  
Yanjun Tang ◽  
Zimin Jin ◽  
Chengyan Zhu ◽  
...  

Functionalized knitted fabric, as a kind of flexible, wearable, and waterproof material capable of conductivity, sensitivity and outstanding hydrophobicity, is valuable for multi-field applications. Herein, the reduced graphene oxide (RGO)-coated knitted fabric (polyester/spandex blended) is prepared, which involves the use of graphite oxide (GO) by modified Hummers method and in-situ chemical reduction with hydrazine hydrate. The treated fabric exhibits a high electrical conductivity (202.09 S/cm) and an outstanding hydrophobicity (140°). The outstanding hydrophobicity is associated with the morphology of the fabric and fiber with reference to pseudo-infiltration. These properties can withstand repeated bending and washing without serious deterioration, maintaining good electrical conductivity (35.70 S/cm) and contact angle (119.39°) after eight standard washing cycles. The material, which has RGO architecture and continuous loop mesh structure, can find wide use in smart garment applications.


Author(s):  
Sara Maira Mohd Hizam ◽  
Nurul Izza Soaid ◽  
Mohamed Shuaib Mohamed Saheed ◽  
Norani Muti Mohamed ◽  
Chong Fai Kait

2019 ◽  
Vol 163 ◽  
pp. 77-85 ◽  
Author(s):  
Faisal Nazeer ◽  
Zhuang Ma ◽  
Lihong Gao ◽  
Fuchi Wang ◽  
Muhammad Abubaker Khan ◽  
...  

RSC Advances ◽  
2015 ◽  
Vol 5 (20) ◽  
pp. 15070-15076 ◽  
Author(s):  
Linxiang He ◽  
Sie Chin Tjong

Nano silver-decorated reduced graphene oxide (Ag–RGO) sheets were synthesized by simply dissolving graphite oxide and silver nitrate inN,N-dimethylformamide and keeping the suspension at 90 °C for 12 h.


2018 ◽  
Vol 136 (10) ◽  
pp. 47164 ◽  
Author(s):  
Xin Zhang ◽  
Yahui Ma ◽  
Yingjin Pei ◽  
Shuojin Zheng ◽  
Qinghong Fang ◽  
...  

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