CAREER: Telechelic triblock copolymers as a platform to design functional colloidal gels

职业：遥爪三嵌段共聚物作为设计功能性胶体凝胶的平台

• 批准号: 2339052
• 负责人: Ryan Poling-Skutvik
• 金额: $ 58.99万
• 依托单位: University of Rhode Island
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-02-15 至 2029-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2339052&HistoricalAwards=false
• 关键词: CAREER; Telechelic; triblock; copolymers; platform

Colloidal gels are a unique class of materials that behave like either solids or liquids depending on processing conditions. This flexibility makes them essential for developing the next generation of battery technology, enabling additive manufacturing processes, and mimicking the performance of biological materials. In most gels, however, the solid-like and liquid-like properties are dependent on each other, drastically limiting their utility in industrial and scientific applications. To address this critical knowledge gap, this award aims to design gels with independent elasticity and viscosity by using polymer additives. These specific polymers possess endgroups that bind to dispersed colloids to generate stiff solid-like materials that readily break down during processing to create low viscosity fluids. This approach will result in efficient and cost-effective materials comprised primarily of solvent but with mechanical properties comparable to high performance engineering materials. The properties of these polymer-linked gels will be tuned and optimized by manipulating polymer chemistry and characterized using optical microscopy and novel rheological procedures. Additionally, this project will engage in targeted outreach efforts focused on recruiting and retaining LGBTQ+ youth in STEM fields to offset persistently low participation rates. Outreach efforts will include hands-on experiential workshops conducted in collaboration with local community organizations, role model introductions and mentorship, and the development of a STEM-focused support network for LGBTQ+ students at the University of Rhode Island. Colloidal gels are complex soft materials encountered throughout scientific and industrial applications ranging from slurries for battery production to synthetic scaffolds for tissue engineering and to inks for 3D printing. The performance of these materials depends critically on the interplay between structural and dynamical effects that underlie their emergent properties. Although many applications require competing design constraints such as robust mechanical stiffness but rapid mass transfer, the properties of most existing colloidal systems remain coupled, reducing synthetic flexibility and limiting their design. This experimental investigation of a novel class of rheological modifiers – telechelic triblock copolymers – aims to decouple the linear and nonlinear mechanical properties of colloidal gels. The chemistry of the triblock copolymers will be manipulated to generate extended conformations that promote bridge formation and drive colloidal self-assembly. Additionally, the resulting structural and dynamic heterogeneity in the polymer-linked gels will be characterized and these hierarchical properties related to nanoscale transport. Finally, the linear and nonlinear rheology of polymer-linked colloidal suspensions will be characterized using novel rheological protocols to identify high-performance yield stress fluids. These fundamental research aims will be integrated into a comprehensive educational and outreach plan that engages LGBTQ+ youth in Rhode Island.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.

胶体凝胶是一种独特的材料，根据加工条件的不同，它的行为类似于固体或液体。这种灵活性使它们对于开发下一代电池技术、实现添加剂制造工艺和模仿生物材料的性能至关重要。然而，在大多数凝胶中，类固体和类液体的性质相互依赖，极大地限制了它们在工业和科学应用中的应用。为了解决这一关键的知识差距，该奖项旨在通过使用聚合物添加剂设计具有独立弹性和粘度的凝胶。这些特定聚合物具有与分散的胶体结合的端基，以生成坚硬的固体状材料，这些材料在加工过程中容易分解，从而产生低粘度流体。这种方法将产生高效和成本效益高的材料，主要由溶剂组成，但具有与高性能工程材料相当的机械性能。这些聚合物连接凝胶的性能将通过操纵聚合物化学进行调整和优化，并使用光学显微镜和新的流变学程序进行表征。此外，该项目将开展有针对性的外联工作，重点是在STEM领域招聘和留住LGBTQ+青年，以抵消持续较低的参与率。外展工作将包括与当地社区组织合作举办的动手体验讲习班、榜样介绍和指导，以及在罗德岛大学为LGBTQ+学生发展以STEM为重点的支持网络。胶体凝胶是一种复杂的软材料，在科学和工业应用中都会遇到，从用于电池生产的泥浆到用于组织工程的合成支架，再到用于3D打印的墨水。这些材料的性能在很大程度上取决于结构效应和动力效应之间的相互作用，这些效应是它们突现特性的基础。尽管许多应用需要相互竞争的设计约束，如坚固的机械刚度和快速的传质，但大多数现有胶体系统的性质仍然是耦合的，降低了合成灵活性并限制了它们的设计。本实验研究了一类新型的流变改性剂--遥螺旋三嵌段共聚物，旨在分离胶体凝胶的线性和非线性力学性质。三嵌段共聚物的化学将被操纵，以产生延长的构象，促进桥的形成和驱动胶体自组装。此外，还将对聚合物连接凝胶中产生的结构和动态异质性进行表征，并将这些分级性质与纳米尺度传输相关。最后，将使用新的流变学协议来表征聚合物连接的胶体悬浮液的线性和非线性流变性，以识别高性能屈服应力流体。这些基本研究目标将被整合到一个全面的教育和推广计划中，该计划吸引罗德岛的LGBTQ+青年参与。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。