方平组织导电面料的设计与心电监测

织物电极是制备长期可穿戴式心电监测设备的重要器件，织物电极的设计开发关系着电极穿戴的舒适性和信号采集的稳定性。方平组织织物浮线长，布面平整，风格独特，适合制备心电电极。基于镀银锦纶纱开发方平组织的导电面料，调控交织密度，织造了多种面电阻的织物电极，并探索其监测人体心电信号的性能，评估监测质量。研究发现，增加织物中导电纱线的交织密度可增大皮肤与电极间的接触面积，织物触感更柔软，织物与人体的阻抗更低，心电信号更清晰。织物有孔隙时更适合长期穿戴和监测人体的心电信号。     

灯芯绒心电织物电极的制备及性能

针对用于心电图长期监测的银/氯化银凝胶电极会刺激皮肤,且凝胶逐渐干涸会导致电极-皮肤接触阻抗增大,影响测量精度的问题,提出以灯芯绒织物为基材,经聚苯胺原位聚合,采用化学镀法在织物表面沉积导电银层制得聚苯胺/银/灯芯绒织物,并组装成织物电极。分别采用SEM、FTIR、TGA、阻抗测试仪和BIOPAC记录仪测试纤维表面形貌及化学组成、织物热稳定性、电极-皮肤接触阻抗、织物电极及凝胶电极的静息心电图。结果表明:织物表面成功沉积了聚苯胺薄膜和致密的导电银层;表面银层可提高其热稳定性;织物电极的电极-皮肤接触阻抗在5～500 Hz下小于1 000 kΩ,且其与凝胶电极的差值随着频率的增大而减小;该电极可测得与凝胶电极相似的心电信号。     

过硫酸铵浓度对聚苯胺/镀银织物电极性能的影响

为了探究过硫酸铵（APS）浓度对化学镀银织物电极性能的影响,得到性能更加优异的织物电极,选用硝酸作为掺杂剂,苯胺（An）单体作为原料,过硫酸铵作为氧化剂,通过改变过硫酸铵浓度,采用原位化学聚合法在织物表面获得较厚的聚苯胺（PANI）沉积层,再利用超声波化学镀银制备导电织物,最后组装成织物电极。利用扫描电子显微镜和电极阻抗测试仪进行测试,得出氧化剂过硫酸铵浓度对聚苯胺/镀银织物电极性能的影响。结果表明:当硝酸浓度为0.5 mol/L,苯胺浓度为0.25 mol/L,过硫酸铵浓度为0.1 mol/L时,所制备镀银织物电极的导电性最好,与皮肤间的阻抗变化曲线更接近于医用Ag/Ag Cl凝胶电极,阻抗值相对最小,在5～100 Hz频率范围内的阻抗均在0.2 MΩ·cm²以下,远小于1 MΩ·cm²,可满足纺织干电极皮肤阻抗标准要求。随着过硫酸铵浓度的增加,制备的织物电极的性能呈下降趋势。     

织物电极监测心电信号与穿戴压力作用机制分析

为探索穿戴压力对纺织结构心电电极采集心电图(ECG)信号质量的影响,开发了基于镀银锦纶丝束和涤纶的平纹和缎纹交织结构的4种导电织物电极。从皮肤-电极接触阻抗、舒适性以及织物方阻与穿戴压力的关系等方面评价了织物电极的性能,并测试了不同穿戴压力(2、5、10 kPa)下4种不同织物电极采集ECG信号的性能。结果表明:在不同穿戴压力下,不同结构的织物电极表现出不同的ECG信号采集能力和舒适性能;随着穿戴压力增加,所测试的导电织物方阻先呈下降趋势,然后趋于稳定,ECG信号质量不断增高;纯导电缎纹结构织物具有更好的透气透湿性,并且舒适性优于平纹结构织物;然而在舒适的穿戴压力(2、5 kPa)下,平纹结构织物电极表现出更好的ECG信号质量。     

用于柔性织物电极的导电纱线耐久性研究

为了提高运动训练领域智能服装的使用寿命,针对镀银纱线耐久性差的问题,提出了一种石墨烯聚合物导电纱线代替其作为织物电极导电材料的方法.通过实验分别比较汗液和光照对导电纱线表面形态、强力和电学性能的影响.结果表明:镀银导电纱线在汗液处理时电阻增加很快、纱线均匀性变差;随着浸泡时间的增加纤维表面镀银层脱落面积逐渐增大,当镀银层表面有缺陷时,破坏过程会加速;光照也会增加镀银纱线的电阻,同时降低电阻均匀性;腈纶石墨烯纱线耐汗液性能比镀银导电纱线有明显的提高,且具有比较稳定的耐光照性能.腈纶石墨烯纱线更适合作为运动训练等场景下具有生理监测功能的织物电极材料.     

碳纤维/涤纶刺绣心电电极制备及其性能

为制备一种生物相容性高的医疗级可穿戴电子服装用人体心电(ECG)监测电极,以碳纤维/涤纶复合长丝为电极导电材料,采用刺绣法开发了一种新型刺绣电极,对电极的电学性能和细胞毒性进行分析,并与镀银锦纶/涤纶刺绣电极进行对比;借助自行研发的可穿戴带式心电监测系统评价织物电极采集ECG信号质量。结果表明:镀银电极电学性能较优,但在长期心电信号监测中,碳基电极的阻抗变化与镀银电极相近;对比医用凝胶电极,2种刺绣电极采集到的ECG信号质量良好,均能满足医疗诊断需求;镀银电极具有很强的细胞毒性,其细胞存活率为3%,而碳基电极的细胞存活率为107%,细胞毒性为0级,具有良好生物相容性,符合医疗体外材料测试标准。     

织物结构对纺织结构电极阻抗性能的影响

以镀银纱线作为原材料,采用织物结构单元成型的方式,通过织物结构分析模拟并结合电化学阻抗谱分析,分别研究了纱线曲屈状态、织物组织、织物密度、纱线连续状态及纱线数量对电极阻抗性能的影响。研究表明：相同长度的纱线在织物中的曲屈状态对电极阻抗性能影响较小;织物密度对电极阻抗性能的影响较小;纱线连续状态及纱线数量对电极阻抗性能的影响较大。为可穿戴医疗监护服装中纺织结构电极的设计提供一定的理论依据。     

织物心电电极优化及在不同相对湿度下的性能比较

为解决用于心电监测的纺织结构电极与皮肤接触时电阻大、心电信号干扰大的问题,采用在织物电极中加入吸湿性纱线的方法进行优化,改善电极-皮肤界面的接触环境。当环境相对湿度改变时,分别测试加入不同种类和配比的吸湿性纱线时织物电极获取的心电信号。结果表明:在高相对湿度条件下,在镀银织物电极中加入吸湿性纱线,不仅能够改善电极与皮肤的接触状态,降低电极与皮肤的接触电阻,提高信号质量,而且有利于增强服装舒适性,降低电极制作成本。     

摩擦纺抗静电防护服用纱的研制

用摩擦纺纱将导电纤维分别置于纱线的表面、中心或均匀分布在纱的横截面中纺成纱线,并织成防护服面料。结果表明,导电纤维置于纱线表面的导电效果最好;导电纤维的含量越大,织物的导电性能越好。如果导电纤维含量达到3．6％时,防护服织物经纬向的表面比电阻可以达到2．0×103Ω,具有理想的抗静电效果。     

聚苯胺基柔性超级电容器的研究进展

基于纺织品的超级电容器具有灵活柔韧、速率快、成本低等优点,是用于可穿戴智能纺织品的理想材料.聚苯胺(PANI)具有良好的导电性、柔韧性,价格较低,易于合成,在超级电容器中具有较大的应用潜力.介绍了聚苯胺(PANI)电极用于超级电容器的最新研究进展,对其在纤维、纱线、织物形式下的电化学性能及柔韧性能进行了归纳.总结了聚苯...     

Investigating the performance of dry textile electrodes for wearable end-uses

Textile electrodes have become popular in recent years for their good skin sensorial comfort and their good integration with clothing, which offers great potential for sensing of signals for wearable end uses. However, in comparison with wet electrodes, dry textile electrodes have much higher and unstable skin-electrode impedance, which could introduce differential noise in signals and cause difficulties in results and diagnosis. To solve this problem, this paper is focused on determining the reasons for this phenomenon and optimizing the performance of textile electrode. Several factors have been examined and the results indicate that the skin-electrode impedance performance is very sensitive to changes of electrode position, size and holding pressure. The fabrication of textile electrode and its optimum holding pressure and size are also described in this paper. Through the implementation of electrocardiogram (ECG) measurements, it was demonstrated that when the electrode size and holding pressure are optimized, the textile electrodes can achieve similar signal performance as wet electrodes.     

An investigation of electronic fabrics for monitoring clothing based on ECG signal acquisition北大核心CSCD

In order to achieve the long, term wearable monitoring of ECG (electrocardiogram) signals and develop soft and smart textiles with excellent durability, electronic fabrics were prepared by using cotton knitted fabric as the base material and 280 D silver, plated conductive sewing thread . Through orthogonal experimental design, ECG signals of electronic fabric under different sewing parameters were gathered and compared with clinical medical ECG to analyze the feasibility of ECG signal. Then, tests of the conductivity, tensile property, abrasion resistance and water washing resistance of electronic fabric were carried out. Borda method was used to balance the acquisition effect of ECG signal and the durability performance of the electronic fabric. This paper provides a basis for the optimization of the electronic fabric based on the ECG signal acquisition. © 2018 China Silk Association. All rights reserved.     

基于石墨烯织物电极的七导联心电监测系统

针对Ag/AgCl凝胶电极不适合长期使用、单导联可穿戴心电监测设备导联数较少的现状,设计了一款基于石墨烯织物电极的七导联可穿戴心电监测系统。该系统由棉/T400高弹心电衣、石墨烯织物电极、七导联心电采集终端及手机应用程序(APP)共4部分组成。对该系统连续工作时间、连续佩戴信号质量以及多使用场景等进行了测试和分析。结果表明:石墨烯织物电极连续佩戴7 d后心电信号信噪比仍达29.8 dB;该系统以250 mA·h容量锂电池在满电情况下连续使用可长达5 d,在静息、步行、慢跑等多种运动状态测试场景中,以及静息自汗的身体状况下,依然可采集到高质量的心电信号,为心电数据智能分析和医生的精确诊断提供有效信息,在心脏疾病的连续远程监护中具有重要应用价值。     

石墨烯/针织复合电极材料的制备及性能测试

为了满足柔性智能可穿戴电子产品的供电需求,设计了一种与之匹配的柔性超级电容器。电极材料是决定超级电容器性能的关键因素,为提高电极材料的电化学性能和耐弯曲性能,以针织物为基底,采用电化学沉积法制备石墨烯/针织复合电极材料。通过SEM测试表征电极材料的表观形貌及结构;通过恒流充放电、循环伏安以及交流阻抗等测试表征电极材料的电化学性能。试验结果表明:石墨烯/涤棉针织复合电极最佳电沉积时间为150 min,比电容为57.76 F/g、电阻为21.14Ω;经过1000次循环充放电后,电容保持率仍然可达82.2%,循环寿命长且耐弯曲性能优异。     

Textile electrodes of jacquard woven fabrics for biosignal measurement

In the last few years, textile electrodes have become an interesting topic for physiological monitoring, steadily developing to be applied in innovative wearable sensing systems. The structure of textile electrodes can be fabricated by weaving, knitting, or embroidering conductive yarn and is now commercially available. The upgraded textile electrode is used in biosignal sensing and was designed in the form of a jacquard woven structure to measure the ECG. In the case of knit fabric, which has piezo‐resistive properties, the textile electrodes were developed by using the fabric’s flexible strain gauges in a bio‐monitoring system. However, the piezo‐resistive sensing fabrics have some shortcomings such as low dynamic range, poor repeatability, and performance deterioration after washing or repeated folding. Woven fabric, which is cloth woven in the warp and weft directions, has less strain properties and can be constructed more uniformly than knit fabric. Therefore, due to their more consistent woven structure, jacquard woven fabrics made with conductive yarn can be manufactured evenly on a large scale and consistently maintain their properties. The woven structure of jacquard electrodes consists of a double‐faced weave and is woven with a silver covering yarn in the weft direction. The proposed textile electrodes were composed of two groups made up of warps with either the unremoved 100% warps or the half‐removed 50% warps of jacquard woven electrodes that were convex or flat and were either with or without conductive paste. The ECG measurements for the textile electrodes were repeated three times in resting conditions. The convex jacquard electrodes of the half‐removed 50% warps with the conductive paste resulted in the most significant SNR improvement (33.67 dB). The purpose of this paper was to investigate a method to design jacquard woven electrodes uniformly on a large scale and to apply it feasibly to ECG measurement.