Silyl Ether Metathesis for Universal Vitrimer Design

用于通用 Vitrimer 设计的甲硅烷基醚复分解

• 批准号: 1810217
• 负责人: Zhibin Guan
• 金额: $ 44.1万
• 依托单位: University of California-Irvine
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-01 至 2023-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1810217&HistoricalAwards=false
• 关键词: Silyl; Ether; Metathesis; Universal; Vitrimer

NON-TECHNICAL SUMMARY:The main objective of this project is to develop a new method for producing dynamic materials made out of polymers that can combine excellent mechanical properties and chemical stability with good reprocessability and recyclability. Polymeric materials play an essential role in addressing many technological challenges including alternative energy, medical/health, and national security/competitiveness. Broadly defined, polymeric materials are classified into two large categories: thermosets and thermoplastics. Thermosets have their molecules permanently connected ("cross-linked") and as a result have excellent mechanical properties, dimensional stability, and resistance to chemicals and solvents. However, a critical limitation of thermosets is that they cannot be reshaped, reprocessed, or recycled since their molecules are permanently stitched together. In contrast, thermoplastic polymers can be reshaped and reprocessed, but they normally have lower mechanical strength, lower structural stability at elevated temperature, and poorer chemical/solvent resistances. This research presents a new chemical strategy that aims to combine the best attributes of both thermoplastics and thermosets. Specifically, a universal strategy will be explored to introduce plasticity, reprocessability and recyclability to various polymer networks and composites through a new silicon-oxygen exchange reaction. Successful demonstration of the proposed strategy could offer significant impact on new materials development, polymer recycling and sustainability, and modern processing technologies including additive manufacturing. This project will also provide extensive opportunities to train graduate and undergraduate students, including underrepresented groups in science. This project will also enable the PI to work with the UCI Mathematics, Engineering, Science Achievement (MESA) Program on a K-12 materials science/chemistry outreach effort with a module focusing on dynamic/self-healing polymers.TECHNICAL SUMMARY:The main objective of this research is to investigate silyl ether metathesis as a new, robust, and universal dynamic covalent chemistry for the design of dynamic polymeric materials. Permanently cross-linked polymers (i.e., thermosets) have excellent mechanical properties, creep resistance and dimensional stability, and chemical/solvent resistance. However, a critical limitation of thermosets is that they cannot be reshaped, reprocessed, or recycled by heat or with solvent. In contrast, thermoplastic polymers can be reshaped and reprocessed, but they normally have lower mechanical strength, lower structural stability at elevated temperature, and poorer chemical/solvent resistances. This project describes a new chemical strategy that aims to combine the excellent attributes of both thermoplastics (reprocessability, recyclability) and thermosets (mechanical strength, creep and solvent resistances). Specifically, a universal strategy is proposed to introduce plasticity, reprocessability and recyclability to various polymer networks and composites through a new silyl ether metathesis reaction. First, the general applicability of silyl ether metathesis will be investigated for vitrimers made of common commodity polymers (Aim 1). Aim 2 details plans for the synthesis of vitrimers from multiple polymers through dynamic reactive blending. This provides a simple way to tailor and improve vitrimer properties. The dynamic mechanical properties of the resulting vitrimers will be carefully investigated and correlated with the structures. Finally, the proposed strategy is extended to the design of inorganic/organic composite vitrimers through silyl ether metathesis between inorganic surfaces and organic polymer matrices (Aim 3). Similarly, structure-property studies will be conducted for the composite vitrimers. Successful demonstration of the proposed strategy could offer significant impact on new materials development, polymer recycling and sustainability, and modern technologies including additive manufacturing.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.

非技术摘要：该项目的主要目的是开发一种新方法，用于生产由聚合物制成的动态材料，该聚合物可以将优秀的机械性能和化学稳定性与良好的可重达性和可回收性结合在一起。聚合物材料在应对许多技术挑战中起着至关重要的作用，包括替代能源，医疗/健康以及国家安全/竞争力。广泛定义的聚合物材料分为两个大类：热塑性和热塑性材料。热固性具有永久连接的分子（“交联”），因此具有出色的机械性能，尺寸稳定性以及对化学物质和溶剂的耐药性。但是，热眠者的关键局限性是由于它们的分子被永久缝合在一起，因此无法重塑，再处理或回收。相比之下，热塑性聚合物可以重塑和重新处理，但通常具有较低的机械强度，在升高温度下的结构稳定性较低，化学/溶剂耐药性较差。这项研究提出了一种新的化学策略，旨在结合热塑性和热固体的最佳属性。 具体而言，将探索一种通用策略，通过新的硅氧交换反应将可塑性，可回收性和可回收性引入各种聚合物网络和复合材料。成功地展示了拟议的策略，可以对新材料开发，聚合物回收和可持续性以及包括增材制造在内的现代加工技术产生重大影响。该项目还将为培训毕业生和本科生提供广泛的机会，包括科学领域的代表性不足的群体。 This project will also enable the PI to work with the UCI Mathematics, Engineering, Science Achievement (MESA) Program on a K-12 materials science/chemistry outreach effort with a module focusing on dynamic/self-healing polymers.TECHNICAL SUMMARY:The main objective of this research is to investigate silyl ether metathesis as a new, robust, and universal dynamic covalent chemistry for the design of dynamic polymeric materials.永久的交联聚合物（即热固体）具有出色的机械性能，蠕变抗性和尺寸稳定性以及化学/溶剂耐药性。但是，热眠者的关键局限性是不能通过热量或用溶剂重塑，重新加工或回收。相比之下，热塑性聚合物可以重塑和重新处理，但通常具有较低的机械强度，在升高温度下的结构稳定性较低，化学/溶剂耐药性较差。 该项目描述了一种新的化学策略，旨在结合热塑性（可回收性，可回收性）和热固性（机械强度，蠕变和溶剂电阻）的出色属性。具体而言，提出了一种普遍的策略，以通过新的Silyl Ether Ether Methathesis反应将可塑性，可回收性和可回收性引入各种聚合物网络和复合材料。首先，将研究由共同商品聚合物制成的玻璃二聚体的一般适用性（AIM 1）。 AIM 2详细详细说明了通过动态反应性混合从多个聚合物合成玻璃二聚体的计划。这提供了一种简单的方法来量身定制和改善玻璃二聚体特性。将仔细研究所得玻璃体的动态机械性能并与结构相关。最后，提出的策略扩展到通过无机表面和有机聚合物矩阵之间的甲硅烷基醚复合的无机/有机复合玻璃体的设计（AIM 3）。同样，将针对复合玻璃二聚体进行结构质体研究。 成功地展示了拟议的战略，可以对新材料开发，聚合物的回收和可持续性以及包括增材制造在内的现代技术产生重大影响。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的智力优点和更广泛影响的审查标准来通过评估来进行评估的。

项目成果

Fluoride‐Catalyzed Siloxane Exchange as a Robust Dynamic Chemistry for High‐Performance Vitrimers

氟化物催化硅氧烷交换作为高性能 Vitrimer 的稳健动态化学

• DOI: 10.1002/adma.202303280
• 发表时间: 2023
• 期刊: Advanced Materials
• 影响因子: 29.4
• 作者: Tretbar, Chase;Castro, Jordan;Yokoyama, Kosuke;Guan, Zhibin
• 通讯作者: Guan, Zhibin