Biodegradable and eco-friendly sensors based on polylactide acid ferroelectrets with adjustable operating lifetime

基于聚丙交酯酸铁电驻极体的可生物降解且环保的传感器，具有可调的工作寿命

• 批准号: 509096131
• 负责人: Professor Dr. Mario Kupnik
• 金额: --
• 依托单位: Fachgebiet Mess- und Sensortechnik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/509096131?language=en
• 关键词: Biodegradable; eco; friendly; sensors; based

A large step towards an eco-friendlier future is the introduction of biodegradable plastic electronics. Such perspective can be seen in the growing demand for small sensors for collecting information from various locations at e.g. entire cities, agricultural infrastructures, manufacturing plants, public energy/water supply networks up to monitoring individual vital functions even inside the human body. Following this trend, this proposal focuses on mechanical-based sensors for quantities such as force, pressure, torque and acceleration. Due to their quasi-permanent built-in electric field, electrets and recently ferroelectrets establish a class of materials that allow for high efficiency and sometimes even independence of external power through energy-harvesting devices, as recently supported DFG-projects are indicating. The material base in those projects are polymers such as Teflon FEP and PTFE, which are not degradable (in a reasonable time period) and definitely contributing to a growing pollution as mentioned above. Therefore, we propose to study a new class of biodegradable electrets and ferroelectrets based on Polylactide Acid (PLA) and its derivatives. These have the potential of an adjustable biodegradability and suited electrical performance, i.e., sufficient charge storage and thermal charge stability. Based on our previous research and in order to obtain the energy efficient electromechanical conversion for these mechanical-based sensors, we propose using a polymer-air composite (hybrid) structure with geometrically defined air-filled and electrically charged voids. These mechanically soft hybrid systems allow achieving high piezoelectric coefficients even for very weak polar polymers such as PLA. Therefore, investigating and improving charge storage and its thermal stability is essential, since these are the most important properties to obtain high and persistent piezoelectric coefficients in biodegradable electret and ferroelectret hybrids to be used in mechanical-based sensors. We plan to identify a strategy for material processing, modeling, improving and characterizing PLA-based ferroelectrets with the aim to tailor charge stability. This will be done under normal environmental conditions raising the scientific question whether operation of PLA-based sensors also is possible under humid environmental conditions, while exposed to an ongoing degradation process. The objective here is tailoring the lifetime of a PLA-based sensor in the range of weeks to months.

生物可降解塑料电子产品的引入是迈向生态友好型未来的一大步。这种观点可以从对小型传感器不断增长的需求中看出，这些传感器用于从各个位置收集信息，例如整个城市，农业基础设施，制造工厂，公共能源/供水网络，甚至监测人体内部的个人重要功能。遵循这一趋势，本提案侧重于基于机械的传感器，用于测量力、压力、扭矩和加速度等量。正如最近支持的dfg项目所表明的那样，由于它们的准永久内置电场，驻极体和最近的铁驻极体建立了一类材料，可以通过能量收集装置实现高效率，有时甚至不依赖外部电源。这些项目中的材料基础是聚四氟乙烯（FEP）和聚四氟乙烯（PTFE）等聚合物，它们是不可降解的（在合理的时间内），并且肯定会导致上述污染日益严重。因此，我们提出研究一类基于聚乳酸及其衍生物的可生物降解驻极体和铁驻极体。它们具有可调节的生物降解性和合适的电性能的潜力，即足够的电荷存储和热电荷稳定性。基于我们之前的研究，为了获得这些基于机械的传感器的节能机电转换，我们建议使用具有几何定义的空气填充和带电空隙的聚合物-空气复合材料（混合）结构。这些机械软混合系统允许实现高压电系数，即使是非常弱极性聚合物，如PLA。因此，研究和改善电荷存储及其热稳定性是至关重要的，因为这些是获得用于机械传感器的可生物降解驻极体和铁驻极体杂化材料的高持久压电系数的最重要的性质。我们计划确定一种材料加工、建模、改进和表征pla基铁驻极体的策略，目的是定制电荷稳定性。这将在正常的环境条件下进行，这提出了一个科学问题，即基于pla的传感器是否也可能在潮湿的环境条件下运行，同时暴露于持续的降解过程中。这里的目标是在几周到几个月的范围内定制基于pla的传感器的寿命。