Liquid-Core Capsules via Interfacial Free Radical Alternating Copolymerization

通过界面自由基交替共聚制备液芯胶囊

• 批准号: 0457453
• 负责人: Carlos Co
• 金额: --
• 依托单位: University of Cincinnati Main Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-04-01 至 2009-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0457453&HistoricalAwards=false
• 关键词: Liquid; Core; Capsules; via; Interfacial

ABSTRACTPI: Carlos C. Co and Chia-Chi Ho Institution: University of CincinnatiProposal Number: 0457453Title: Liquid-Core Capsules via Interfacial Free Radical Alternating CopolymerizationResearch: Liquid-core capsules have application in the high efficiency encapsulation and controlled delivery of drugs, dyes, enzymes, etc. These applications have driven the rapid development of innovative techniques, based on layer-by-layer assembly, shell polymerization of particles and dendrimers followed by core-removal, microphase separation of core-shell latexes, and vesicles, to confine polymerization or assembly of encapsulants at the interface. However, all of these techniques require, in one way or another, procedures and materials, such as repeated centrifugation-washing, sintering, core-removal, microphase separation, vesicle templates, or block copolymers, that limit control of shell thickness and permeability, preclude direct encapsulation of substrates, or hamper large-scale practical application. The aim of this project is to study interfacial free-radical alternating copolymerization for direct encapsulation of liquid drops within a polymer shell without the need for a solid core or vesicle template. The approach for making liquid-core capsules is based on a free-radical analogy of interfacial condensation principles routinely demonstrated with the nylon rope trick. Instead of diamines and diacid chlorides that react uncontrollably upon contact, oil- and water-soluble vinyl ethers and alkyl maleates are alternately copolymerized at interfaces via a free-radical mechanism. The objectives of the work are to: 1.Elucidate the mechanism through which liquid-core capsules are formed during interfacial polymerization 2. Demonstrate dynamic control of shell permeability for aqueous-core capsules The underlying principles and methodology of this type of polymerization allows for the direct encapsulation of many substrates through a highly scalable and inexpensive process. The general principle of interfacial free-radical alternating copolymerization has potentially significant impacts that extend beyond liquid-core capsules and into many established nanotechnologies where the preponderance of interfaces accentuates the significance of interfacial polymerizations. Broader Impacts: Broader impacts of this project include the introduction, education, and training of high school, undergraduate, and graduate students in the principles of radical and condensation polymerizations, interfacial phenomena, and complex fluids. Special effort will be made to recruit American and minority students to pursue advanced studies. In particular, engineering education will be promoted to under-represented groups via UC programs aimed at recruiting students from the large black population in the city of Cincinnati. The free-radical polymerization approach to liquid-core capsule formation proposed here, itself promises broad impact from a commercial standpoint due to its low cost and the ease with which it can be implemented on a large scale.

摘要：卡洛斯C。单位：中国科学院长春研究所项目编号：0457453项目名称：通过界面自由基交替共聚制备液芯胶囊研究成果：液芯胶囊在药物、染料、酶等的高效包封和控释方面有应用，这些应用推动了创新技术的快速发展，基于逐层组装，颗粒和树枝状聚合物的壳聚合，然后核去除，核-壳胶乳和囊泡的微相分离，以限制澄清剂在界面处的聚合或组装。 然而，所有这些技术都以这样或那样的方式需要程序和材料，例如重复的离心洗涤、烧结、核去除、微相分离、囊泡模板或嵌段共聚物，这限制了对壳厚度和渗透性的控制，妨碍了基底的直接包封，或妨碍了大规模的实际应用。该项目的目的是研究界面自由基交替共聚，用于在聚合物壳内直接封装液滴，而不需要固体核或囊泡模板。 制造液芯胶囊的方法是基于自由基模拟界面冷凝原理，通常用尼龙绳技巧证明。 代替在接触时不受控制地反应的二胺和二酰氯，油溶性和水溶性乙烯基醚和马来酸烷基酯经由自由基机制在界面处交替共聚。 本工作的目的是：1.阐明界面聚合过程中液核胶囊形成的机理。演示水核胶囊壳渗透性的动态控制这种类型的聚合的基本原理和方法允许通过高度可扩展和廉价的工艺直接封装许多基质。 界面自由基交替共聚的一般原理具有潜在的显著影响，其延伸超出液核胶囊，并进入许多已建立的纳米技术，其中界面的优势突出了界面聚合的重要性。更广泛的影响：该项目的更广泛的影响包括介绍，教育和培训高中，本科和研究生的自由基和缩聚反应，界面现象和复杂流体的原则。 将特别努力招收美国和少数民族学生继续深造。 特别是，工程教育将通过旨在从辛辛那提市的大量黑人人口中招收学生的加州大学项目推广到代表性不足的群体。 这里提出的液核胶囊形成的自由基聚合方法本身由于其低成本和易于大规模实施而从商业角度来看具有广泛的影响。