导电复合水凝胶的分类及其在柔性可穿戴设备中的应用

江文静; 廖静文; 张雪慧; 王艳芹

doi:10.13801/j.cnki.fhclxb.20220926.002

导电复合水凝胶的分类及其在柔性可穿戴设备中的应用

doi: 10.13801/j.cnki.fhclxb.20220926.002

江文静¹,
廖静文¹,
张雪慧¹,
王艳芹^{1, 2, ,}

1.
太原理工大学　生物医学工程学院，太原 030024
2.
山西浙大新材料与化工研究院，太原 030024

基金项目: 山西省自然科学基金(2021-0302123158)；山西浙大新材料与化工研究院(2022 SX-TD023)

详细信息

通讯作者:
王艳芹，博士，副教授，硕士生导师，研究方向为生物医用高分子材料　E-mail: wangyanqin@tyut.edu.cn

中图分类号: R318.08
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出版历程
- 收稿日期: 2022-07-25
- 修回日期: 2022-09-12
- 录用日期: 2022-09-14
- 网络出版日期: 2022-09-27
- 刊出日期: 2023-04-15

Classification of conductive composite hydrogels and their application in flexible wearable devices

1.
College of Biomedical Engineering, Taiyuan University of Technology, Taiyuan 030024, China
2.
Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering, Taiyuan 030024, China

Funds: Natural Science Foundation of Shanxi Province (2021-0302123158); Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering (2022 SX-TD023)

摘要

摘要: 近年来，基于水凝胶的导电材料及其作为柔性可穿戴设备的应用引起了人们的广泛关注。柔性可穿戴设备不仅可以采集人体生理信号用于远程健康监测，还在人机界面、软机器人等方面展示出巨大的应用潜力。导电水凝胶所具有的良好导电性、高延伸性、可调柔韧性、生物兼容性和多重刺激响应性等优点使其成为制备柔性可穿戴设备的理想材料。到目前为止，各种导电材料被广泛用于制作导电复合水凝胶。本文根据导电材料对导电复合水凝胶进行分类，包括离子导电水凝胶(基于盐离子、离子液体、聚电解质等导电物质)、电子导电水凝胶(基于导电聚合物基、碳材料、MXene和金属等导电物质)两大类，并介绍了导电水凝胶在人体运动监测、健康监测、人机界面等柔性可穿戴设备中的应用进展。
- 水凝胶 /
- 导电 /
- 可穿戴设备 /
- 智能传感 /
- 人体运动监测
Abstract: In recent years, hydrogel-based conductive materials as flexible wearable devices have attracted wide attention. Flexible wearable devices can not only be used to collect physiological signals of human body for remote health monitoring, but also show great application potential in man-machine interface, soft robot and other aspects. Conductive hydrogels with good electrical conductivity, high extensibility, adjustable flexibility, biocompatibility and multiple stimulus response become an ideal material for flexible wearable devices. Up to now, various conductive materials have been widely used to prepare conductive hydrogels. In this paper, conductive composite hydrogels are classified according to conductive materials, including ionic conductive hydrogels (based on salt ions, ionic liquids, polyelectrolytes) and electronic conductive hydrogels (based on conductive polymers, carbon materials, MXene and metal), and then introduce the application progress of conductive hydrogels in flexible wearable devices such as human movement monitoring, health monitoring and human-machine interface.
- hydrogel /
- conductivity /
- wearable devices /
- intelligent sensor /
- human motion monitoring

HTML全文

图 1 相变可调凝胶 (PTTGC凝胶)的设计、制备和性能：(a) PTTGC凝胶的合成与构成；(b) PTTGC凝胶内部成分之间的强氢键和静电相互作用^[35]

Figure 1. Design, preparation, and properties of the phase-transition-tunable gel (PTTGC gel): (a) Synthesis and formation of a PTTGC gel; (b) Strong hydrogen bonds and electrostatic interactions between internal components of PTTGC gel^[35]

PAAm—Polyacrylamide; GC—Clay composite

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图 2 (a) 通过溶胶-凝胶法从乙烯基三乙氧基硅烷(VTES)合成乙烯基官能化二氧化硅纳米粒子(VSNPs)；(b) 甲基丙烯酸磺基甜菜碱 (SBMA)两性离子单体的合成；(c) P(AM-SBMA-AMPS)-SiO₂水凝胶的合成示意图^[38]

Figure 2. (a) Synthesis of vinyl-functionalized silica nanoparticles (VSNPs) from vinyltriethoxysilane (VTES) by a sol-gel process; (b) Synthesis of sulfobetaine methacrylate (SBMA) zwitterionic monomer; (c) Schematic fabrication of P(AM-SBMA-AMPS)-SiO₂ hydrogels^[38]

AM—Acrylamide; AMPS—2-acrylamido-2-methyl-1-propanesulfonic acid

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图 3 各向异性聚乙烯醇(PVA)/聚苯胺(PANI)水凝胶的制备流程示意图^[45]

Figure 3. Schematic diagram of the preparation procedure of the anisotropic polyvinyl alcohol(PVA)/polyaniline(PANI) hydrogel^[45]

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图 4 制备导电还原氧化石墨烯/甲基丙烯酰化明胶(r(GO/GelMA))水凝胶管的示意图，该管道由GO/GelMA复合水凝胶聚合并随后温和化学还原成r(GO/GelMA)^[49]

Figure 4. Schematic outline of the production of a conductive reduced GO/GelMA (r(GO/GelMA)) hydrogel conduit consisting of polymerization of GO/GelMA compositehydrogel and its subsequent mild chemical reduction to r(GO/GelMA)^[49]

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图 5 碳纳米管/疏水缔合聚丙烯酰胺(CNTs/HAPAAm) 水凝胶的制备过程示意图^[51]

Figure 5. Schematic illustration of the preparation process for the CNTs/hydrophobically associated polyacrylamide (CNTs/HAPAAm) hydrogel^[51]

APS—Ammonium persulfate; TEMED—N,N,N',N'-tetramethylethylenediamine; SDS—Sodium dodecyl sulfate; LMA—Lauryl methacrylate; AAm—Acrylamide

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图 6 MXene-聚丙烯酸(PAA)-无定形碳酸钙(ACC)(MXene-PAA-ACC)水凝胶的制备示意图^[58]

Figure 6. Schematic illustration of the fabrication of the MXene-poly(acrylic acid)(PAA)-amorphous calcium carbonate(ACC) hydrogel^[58]

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图 7 抗菌导电水凝胶(ACGs)的制备^[62]

Figure 7. Synthesis of antibacterial conductive hydrogels (ACGs)^[62]

MBA—N,N'-methylenebisacrylamide; KPS—Potassium persulfate; NIPAM—N-isopropyl acrylamide; AgNWs—Silver nanowires; PG—Precursor gel

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图 8 可穿戴、可愈合和瞬时表皮传感器的制备：(a) PVA-LMPs水凝胶的形成；(b) 所制备的PVA-LMPs水凝胶可以可逆的自愈^[63]

Figure 8. Preparation of the wearable, healable, and transient epidermal sensors: (a) Formation of PVA-LMPs hydrogel; (b) As-prepared PVA-LMPs hydrogel could be reversibly self-healed^[63]

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图 9 (a) 大面积水凝胶薄膜的照片、SEM图像及肘部运动过程中的电流-时间曲线^[64]；(b) 具有坚固界面的结构凝胶复合材料(SGC)的制造及水下实时脉冲检测器^[66]

Figure 9. (a) Photograph and SEM image of large-area hydrogel film, and current-time curve during elbow motion^[64]; (b) Fabrication of structural gel composite (SGC) with robust interface and an underwater real-time pulse detector^[66]

ΔI—Current variation under certain pressure; I₀—Current without pressure; ΔR—Relative resistance change; R₀—Resistance without applied strain

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图 10 (a) 两性离子导电水凝胶薄膜的制备；(b) 表皮触控面板的结构和操作。(表皮集成触控面板示意图。通过表皮触摸面板玩愤怒的小鸟的操作照片：当手指接触面板时，弹弓被弹弓捕获；当手指离开面板时，弹弓被释放，小鸟起飞；目标被小鸟打断。使用面板下棋的照片记录：手指点击触摸面板上的棋子位置时选择了一个棋子；棋子选择了棋盘的另一个位置，棋子移动；棋子移动到了目标位置)^[69]

Figure 10. (a) Preparation of zwitterionic conducting hydrogel films; (b) Structure and operation of an epidermal touch panel. (Schematic illustration of an epidermal integrated touch panel. Operational photographs of playing Angry Birds by an epidermal touch panel. An Angry Bird was captured by the slingshot when a finger touched the panel. The slingshot was released when the finger left the panel, and the bird took off, the target was broken by the bird. Photographs record of playing Chess using the panel. A chess piece was selected when the finger clicked the piece position on the touch panel. Another position of the chessboard was chosen for the chess piece, and the chess piece shifted. The chess piece was shift to the target position)^[69]

PDMS—Poly(dimethylsiloxane); VHB—Dielectric elastomer very high bond

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图 11 实时人体健康监测：(a) 监测麻醉大鼠心脏的照片并记录阻力随时间变化以监测心跳的变化；(b) 监测麻醉大鼠腹部创伤的照片并记录阻力随时间的变化以监测腹部伤口的变化；(c) 监测腹部伤口触摸或按压的照片并记录的阻力随时间变化，用于监测腹部伤口触摸或按压的变化(箭头表示当时短暂按压水凝胶)；(d) 监测内脏器官(肝脏)的照片并记录阻力随时间变化以监测肝脏的变化^[72]

Figure 11. Real-time human health monitoring: (a) Photographs of monitoring the hearts of anesthetized rats and recorded resistance with time to monitor changes in heartbeats; (b) Photographs of monitoring the abdominal wounds in anesthetized rats and recorded resistance with time to monitor changes in abdominal wounds; (c) Photographs of monitoring the touching or pressing of abdominal wounds and recorded resistance with time for monitoring changes in touching or pressing on abdominal wounds (Arrow indicates a brief press on the hydrogel at that time point); (d) Photographs of monitoring a visceral organ (liver) and recorded resistance with time for monitoring changes in the liver^[72]

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表 1 基于各种导电材料的导电水凝胶的综合性能比较

Table 1. Comprehensive performance comparison of conductive hydrogels based on various conductive materials

Conductive hydrogel	Conductive material	Components of polymer networks	Conductivity/ (S·m⁻¹)	Tensile strain/%	Temperature range	Ref.
Saline solution	AlCl₃	CMCP(AA-AM)	2	963	—	[34]
	ZnCl₂	Gelatin/PAAm-GC	1.68	—	−60-60℃	[35]
	CaCl₂	PAA/ISP	1.86	890	−20℃-RT	[36]
IL	[BMIM]Cl	P(AM-HEA)/SSS	8.4	1310	−25-75℃	[37]
Polyelectrolyte	SBMA	P(AM-AMPS)-SiO₂	3.4	1000	−20-100℃	[38]
Conductive Polymer	PANI	PNIPAm/AMPS	~0.027	—	—	[43]
	PPy	GelMA-PAM	~0.071	—	—	[44]
	PANI	PVA	20.5	100	—	[45]
	PANI	ANF-PVA	2.02	140	—	[46]
Carbon-based materials	GO	GelMA	~0.87	—	—	[49]
	CNT	PS/TC	—	83.2	—	[50]
	CNT	HAPAAm	~1.7	3000	—	[51]
MXene	MXene	PAA-ACC	—	450	—	[58]
	MXene	Chitosan	0.04	1900	—	[57]
	MXene	PAA/PAM/TA	—	560	—	[59]
Metal/LMs	Ag/TA@CNCs	PVA	4.61	4000	—	[60]
—	Au/SiO₂	GelMA	—	~70	—	[61]
—	AgNW	PNIPAM	~0.025	300	—	[62]
—	LMPs	PVA	0.375	—	—	[63]
Notes: IL—Ionic liquid; LMs—Liquid metal; [BMIM]Cl—1-butyl-3-methylimidazolium chloride; PPy—Polypyrrole; TA—Tannic acid; AA—Acrylic acid; CMC—Carboxymethyl cellulose; ISP—Ice structuring proteins; HEA—2-hydroxyethyl acrylate; SSS—Sodium p-styrene sulfonate; ANF—Aramid nanofiber; PS—Pigskin; TC—Oxidized-nanocellulose; RT—Room temperature.

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