Triggering Chemical Degradation of Plastics at End of Life Using Light and Environmentally-Neutral Nanoparticles

这项研究的重点是开发策略，通过添加廉价的颗粒并在外加光线下产生内部热量，可控制地打破聚合物材料中的化学键。这项研究的潜在好处包括开发具有附加功能的材料--根据命令降解的能力。因此，这种知识可以使塑料在使用过程中坚固耐用，然后在不再需要该物品时迅速触发并破坏效率。这一概念遵循绿色设计原则，使坚固的物体能够被尽可能多次地利用(而不会损坏)，然后在生命结束时故意转化为良性产品。这一策略将与化学降解协同工作，并为塑料的细菌修复提供合适的降解材料。本研究验证了一种假设，即嵌入的纳米颗粒在光热加热时在聚合物内部产生强烈的不均匀温度梯度，可以有效地触发热诱导的键断裂，可能的材料内部碎裂，并因此强烈增强降解。金属纳米颗粒强烈地吸收光线并产生热量。颗粒将被纳入商业热塑性塑料和可生物降解聚合物中。光热方案的降解效率将与常规加热的效率进行比较。铝纳米颗粒之所以成为目标，是因为它们价格低廉，而且由于它们与氧化铝发生反应，可以提供额外的热能。铝是地球上储量最丰富的金属，氧化铝是一种环境中性的最终产品。这项工作的另一个科学成果将是关于铝纳米颗粒中光热效应的更多知识，这一点以前没有得到很好的探索。纺织工程高级设计团队将获得资助，探索辅助主题，如细菌修复，这将增强这项工作的研究目标，并有助于这些未来工程师和科学家的教育。高级设计学生还将开发一种互动体验，演示聚合物降解，用于高中生暑期项目，历史上，高中生的人口结构中有25%或更多的STEM少数民族没有代表。

This research focuses on developing strategies to controllably break chemical bonds within polymeric material by adding an inexpensive particle and generating internal heat with applied light. Potential benefits of this research include the development of materials with an additional functionality -- the ability to degrade upon command. Thus this knowledge could enable plastics that are strong and robust during use and then can be triggered to quickly and efficiency break down when the item is no longer needed. This concept follows green design principles by enabling a robust object which can be utilized as many times as possible (without breaking down) and then intentionally transformed into a benign product at the end of life. This strategy would work cooperatively with chemical degradation and provide suitably degraded material for bacterial remediation of plastic.This research tests the hypothesis that the strongly inhomogeneous temperature gradients created in the interior of polymers upon photothermal heating of embedded nanoparticles can be utilized to efficiently trigger thermally-induced bond breaking, possible internal fragmentation of the material, and strongly enhanced degradation as a consequence. Metal nanoparticles strongly absorb light and generate heat as a result. Particles will be incorporated within commercial thermoplastics and biodegradable polymers. The degradation efficacy of photothermal protocols will be compare with that from conventional heating. Aluminum nanoparticles are targeted because they are inexpensive and provide additional thermal energy due to their reaction to aluminum oxide. Aluminum is the most abundant metal on earth and aluminum oxide is an environmentally neutral end product. Enhanced knowledge about the photothermal effect in aluminum nanoparticles, which has previously not been well-explored, will be an additional scientific outcome of this work. Textile Engineering senior design teams will be funded to explore auxiliary topics, such as bacterial remediation, that will enhance the research objectives of this work and contribute to the education of these future engineers and scientists. Senior design students will also develop an interactive experience demonstrating polymer degradation for use in a summer program for high school students, whose demographic historically contains 25% or more STEM unrepresented minorities.