CAREER: Recycled Polymers of Enhanced Strength and Toughness: Predicting Failure and Unraveling Deformation to Enable Circular Transitions

该学院早期职业发展（CAREER）资助支持旨在了解回收聚合物（称为聚合物）变形和失效的研究。由于机械性能较差，再生塑料一直无法取代原始塑料。这导致资源枯竭、浪费和污染的挑战。初步工作表明，通过在其中引入不同的自组装相来改变微胶囊的内部结构，可以提高其机械性能。然而，调查这些自组装结构的变形和失效，这是必要的，使其更广泛的采用和使用，是非常具有挑战性的，由于其复杂的性质。该奖项支持基础研究，通过复杂的实验和人工智能来预测变形和失效是如何发生的。这些发现将提高科学认识，促进先进再生材料的发展，使美国多个行业受益，促进可持续发展，保护国家资源。与此同时，教育，外展和边境影响活动旨在通过提供新的工程技能和改善边缘化个人的职业前景来塑造多元化和灵活的美国劳动力，重点是从监禁中重新进入劳动力市场的个人。该补助金旨在支持研究，通过综合的实验和计算方法，促进对具有提高强度和韧性的自组装内部形态的变形和失效的理解。这项研究工作的新力学发现将能够用具有类似机械性能的回收塑料替代原始塑料，从而实现循环过渡，并解决紧迫的塑料污染挑战。通过利用存在于非均相嵌段共聚物的不混溶聚合物共混物中的内在势能，将改变它们的内部结构。通过这种方式，将开发出具有相分离、自组装三维形态的增强机械性能的复合材料。将探索这些岩石的结构-性能空间，并研究其复杂的失效和变形，同时开发先进的实验力学仪器来支持这些努力。将高通量、大数据生成实验与最先进的人工智能算法相结合，将能够预测失效演变并理解强度和韧性增强机制。这些预测将揭示非均质聚合物复合材料的新变形机制。这些知识也将使建立新的，可靠的标准裂纹分支，弯曲和分叉，这已经逃避了几十年的研究人员。研究工作将与教育、外展和更广泛的影响活动紧密联系在一起，这些活动将致力于通过将可持续性嵌入力学课程，并让受正义影响的青年参与工程科学，实现综合和包容的力学教育。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。

This Faculty Early Career Development (CAREER) grant supports research that aims to understand the deformation and failure of recycled polymers, known as recyclates. Recyclates have been unable to replace virgin plastics because of their poor mechanical performance. This leads to resource depletion, waste, and pollution challenges. Preliminary work suggests that altering the internal structure of recyclates, by introducing distinct, self-assembled phases within them, improves their mechanical performance. However, investigating the deformation and failure of these self-assembled structures, which is necessary to enable their wider adoption and use, is extremely challenging due to their complex nature. This award supports fundamental research to predict how deformation and failure occurs in recyclates through sophisticated experiments and artificial intelligence. The findings will enhance scientific understanding and foster the development of advanced, recycled materials that could benefit multiple U.S. industries, advance sustainability, and conserve national resources. In parallel, the education, outreach, and borader impact activities aim to shape a diverse and agile U.S. workforce by offering new engineering skills and improving career prospects of marginalized individuals, with emphasis on individuals reentering the workforce from incarceration. This grant aims to support research that advances understanding of the deformation and failure of recyclates exhibiting self-assembled internal morphologies of improved strength and toughness through an integrated experimental and computational approach. The new mechanics discoveries by this research effort will enable the substitution of virgin plastics with recycled ones of similar mechanical performance resulting in circular transitions and addressing the pressing plastic pollution challenge. By exploiting the built-in energy potential present in immiscible polymer blends of heterogeneous recyclates, their internal architecture will be altered. This way, composites of enhanced mechanical properties with phase-separated, self-assembled three-dimensional morphologies, induced by thermophoresis, will be developed. The structure-property space of these recyclates will be explored and their complex failure and deformation will be investigated, while developing sophisticated experimental mechanics instrumentation to support such efforts. Coupling high-throughput, big-data generating experiments with state-of-the-art artificial intelligence algorithms will enable the prediction of failure evolution and the understanding of strength and toughness enhancement mechanisms. These predictions will unravel new deformation mechanisms for heterogeneous polymer composites. Such knowledge will also enable the establishment of new, reliable criteria for crack branching, curving and bifurcation, which have eluded researchers for decades. The research efforts will be closely tied to education, outreach, and broader impact activities which will work towards an integrated and inclusive mechanics education, by embedding sustainability in mechanics courses and engaging justice-impacted youth with engineering science.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.