【作者】 陈洁；

【导师】 杨旭东； LI Qiao；

【作者基本信息】 东华大学 ， 纺织科学与工程， 2025， 硕士

【摘要】 柔性可穿戴电子设备因其舒适性、柔软性、轻便性等优点在人机交互、生物医疗、远程通信等领域得到了越来越广泛的研究。纺织材料作为人体的“第二皮肤”,具有优良的穿戴舒适性而被视为柔性可穿戴电子设备中各个电子元件集成的理想载体。目前,基于纺织材料的织物电路仍面临着在大变形下导电稳定性差、在反复变形下疲劳寿命不足、与电子元件互连处可靠性低等缺点。针织物由于其特别的线圈结构而表现出优异的拉伸性和柔软性,因此本课题将选择合适的导电线材引入针织物来制备具有良好的导电稳定性和疲劳寿命的柔性针织导电通道,并基于此针织导电通道探究电路间可靠互连的方式,具体研究内容和结论如下:第一部分是导电线材的选择和针织导电通道的设计、制备及其性能表征。选择耐高低温、柔韧、导电稳定的四氟薄膜绕包镀银铜丝作为导电线材,根据对导电性、动态电力学性能、可编织性等性能的测试和分析,挑选出规格为0.03 mm~*7的导电线材作为后续电路的导电通道。在合适的工艺方案下利用针织技术制备出柔性针织导电通道并测试其各项性能,结果表明:它的静态电阻为0.91Ω左右,断裂前电阻变化率在1.05%左右,在500%、400%、300%高应变下的疲劳拉伸次数分别在815次、2190次和4943次左右。根据Coffin-Manson方程计算得到,针织导电通道在30%和15%下的预估疲劳寿命分别为1.92×10~7次和2.25×10~8次。说明在人体正常活动的应变下,针织导电通道具有良好的导电稳定性和疲劳寿命。第二部分是针织导电通道间的机械式互连设计、制备及其性能表征。本部分包括两个方向,即针织导电通道的导电线材间机械式互连和电子元件间机械式互连。在导电线材间的机械式互连研究中,选择了轻质、成本低、操作简单的常见五爪扣和四合扣进行互连实验,并设置1 cm、2 cm、3 cm三种不同的互连长度。结果表明:纽扣互连后针织导电通道的导电性能均没有明显减弱,在单次拉伸下断裂前电阻变化率均小于2%,使用四合扣进行互连、互连长度为3 cm时有最优的拉伸性,达到了728.7%左右。该方案下的互连样品在500%、400%和300%大应变下的疲劳拉伸次数分别为640次、1262次和2575次左右。在人体正常活动应变下(应变30%)循环拉伸10000次的过程中,该互连方案下的样品能够保持良好的导电性能,电阻变化不超过0.1Ω。基于该方案继续探究了电子元件间的纽扣式互连可靠性,将织物基温度传感器与设计的织物电路进行机械式互连,获得温敏电路并对该温敏电路的传感性能、导电稳定性和疲劳寿命等进行测试。结果表明:发现在0%、15%和30%应变下,样品的性能相较于原织物基温度传感器没有明显变化,在30%应变下循环拉伸10000次的过程中电阻变化小于0.2Ω。最后成功设计了由多个传感器集成的针织传感网络,有望用于人体体温的长时间、多点监测。第三部分是针织排线与外部硬质接口间的互连设计、制备及其性能表征。使用USB/Type-C端子作为外部硬质接口,将其与具有四条导电通道的针织排线两端进行互连,选择焊接并利用硅胶材料对焊接处进行封装的复合连接方法,以减少织物电路到硬质接口间的应变梯度。结果表明:互连后针织排线四条导电通道的断裂前电阻变化率在1.68%～2.23%之间,电阻变化的幅度均小于0.1Ω,断裂伸长率在460%～560%之间。在400%、300%和200%三种应变下,互连后导电通道的疲劳拉伸次数分别在132～206次、640～864次、2867～3457次之间。在30%应变下循环拉伸10000次的过程中,四条导电通道的电阻保持在0.9Ω～1.2Ω之间,单条通道的电阻变化均不超过0.2Ω。综上所述,本文利用针织技术制备了在变形下导电稳定、在反复变形下疲劳寿命良好的针织导电通道,并基于该织物电路探究了电路间可靠的互连方法,为柔性可穿戴电子设备的开发提供了一定的参考。更多还原

【Abstract】 Flexible wearable electronic devices have been more and more widely studied in the fields of human-computer interaction,biomedicine,and remote communication due to their comfort,softness,and portability.As the’second skin’of human body,textile materials have excellent wearing comfort and are regarded as the ideal carrier for the integration of various electronic components in flexible wearable electronic devices.At present,fabric circuits based on textile materials still face the disadvantages of poor conductivity stability under large deformation,insufficient fatigue life under repeated deformation,and low reliability at interconnections with electronic components.Knitted fabrics exhibit excellent stretchability and softness due to their special coil structure.Therefore,this paper selects appropriate conductive wires to introduce knitted fabrics to prepare flexible knitted conductive track with good conductive stability and fatigue life.Based on the knitted conductive track,the reliable interconnections between circuits are explored.The specific research contents and conclusions are as follows:The first part is the selection of conductive wire and the design,preparation and performance characterization of knitted conductive track.The silver-coated copper wire wrapped by tetrafluoroethylene film with high/low temperature change resistance,flexibility and stable conductivity is selected as the conductive wire.According to the test and analysis of conductivity,dynamic electro-mechanical properties and weavability,the conductive wire with a specification of 0.03 mm~*7 is selected as the conductive track of the subsequent knitted conductive track.The flexible knitted structure circuit is prepared by knitting technology under the appropriate process scheme and its various properties are tested.The results show that its static resistance is about 0.91Ω,the change rate of resistance before fracture is about 1.05%,and the fatigue times under the strains of 500%,400%,300%are about 815 times,2190 times and 4943 times respectively.According to the Coffin-Manson equation,the predicted fatigue times of knitted conductive track under the strains of 30%and 15%are 1.92×10~7 times and 2.25×10~8 times,respectively.It shows that the knitted conductive track has good conductive stability and fatigue life under the strain during normal human activity.The second part is the design,preparation and performance characterization of mechanical interconnection between knitted conductive track.This part covers two directions,namely the mechanical interconnection between conductive wires and the mechanical interconnection between electronic components in knitted conductive tracks.In the research of mechanical interconnection between conductive wires,common five-claw buckles and four-snap buckles with light weight,low cost and simple operation are selected for interconnection experiments,and three different interconnection lengths of 1 cm,2 cm and 3 cm are set.The results show that the electrical conductivity of the knitted conductive track after button interconnecion is not significantly weakened,and the resistance change rate before fracture is less than 2%.When the four-snap buckle is used for interconnection and the interconnection length is 3 cm,there is the best stretchability,reaching about 728.7%.The fatigue life of the interconnect samples under this scheme is about 640 times,1262 times and 2575 times under the strains of 500%,400%and300%,respectively.In the process of cyclic stretching 10000 times under the strain of 30%,the samples under this interconnection scheme can maintain good electrical conductivity,and the resistance change does not exceed 0.1Ω.Based on this scheme,the reliability of button-type interconnection between electronic components is further explored.The fabric-based temperature sensor is mechanically interconnected with the designed fabric circuit to obtain the temperature-sensitive circuit,and the sensing performance,conductive stability and fatigue life of the temperature-sensitive circuit are tested.The results show that it is found that at strains of0%,15%and 30%,the performance of the samples does not change significantly compared with the original fabric-based temperature sensor.The resistance change is less than 0.2Ωduring the process of cyclic stretching for 10000 times at the strain of 30%.Finally,a knitted sensor network integrated by multiple sensors is successfully designed,which is expected to be used for long-term and multi-point monitoring of human body temperature.The third part is the interconnection design,preparation and performance characterization between the knitted cable and the external rigid interfaces.The USB/Type-C terminals are selected as the external rigid interfaces to interconnect with the two ends of the knitted cable with four conductive track.The interconnection method of welding and using silicone to encapsulate the mold at the weld is selected.It can reduce the strain gradient between the fabric circuit and the external rigid interfaces.The results show that the resistance change rate of the four conductive track before fracture is between 1.68%～2.23%,the amplitude of resistance change is less than 0.1Ω,and the elongation at break is between 460%～560%.Under the three strains of 400%,300%and 200%,the fatigue times of the conductive track after interconnection are between 132～206 times,640～864 times and 2867～3457 times,respectively.In the process of cyclic stretching 10000 times under the strain of 30%,the resistance of the four conductive track remains between 0.9Ω～1.2Ω,and the resistance change of each track does not exceed0.2Ω.In summary,a knitted conductive track with stable conductivity under deformation and good fatigue life under cyclic stretching is prepared by knitting technology.Based on this circuit,reliable interconnection methods between circuits are explored,which provides a certain reference for the development of flexible wearable electronic devices.更多还原