GOALI: Balanced Surfactants for Self-Assembly of Highly Immiscible Polymers

目标：用于高度不混溶聚合物自组装的平衡表面活性剂

• 批准号: 0305711
• 负责人: Nitash Balsara
• 金额: $ 23.58万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-15 至 2006-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0305711&HistoricalAwards=false
• 关键词: GOALI; Balanced; Surfactants; Self; Assembly

Nitash Balsara - University of California - BerkeleyDavid Lohse - ExxonMobilGOALI: Balanced Surfactants for Self-Assembly of Highly Immiscible PolymersIntellectual Merit of Proposed ActivityThe objective of the proposed work is to build a library of surfactants for controlling the self-assembly in mixtures of highly immiscible polymers. This will enable the creation of newnanostructured polymer materials. It may also enable reusing commingled polymeric waste. The approach represents a departure from the large body of previous experimental and theoretical work in this field which relied on the surfactancy of A-B copolymers for organizing mixtures of A and B homopolymers. It is now recognized that these types of copolymers can only organize interfaces if the homopolymers are weakly immiscible. The surfactant that will be used in the research is a balanced A-C block copolymer. The notion of balance is adapted from the literature on surfactancy in aqueous systems. Nonionic surfactants with balanced hydrophobic and hydrophilic character have been successful in creating nanoscale organization in oil/water mixture in spite of their high degree of incompatibility. The reseserch deals with the application of this principle to polymers. Experiments will be conducted on mixtures of highly immiscible polyolefins, polybutene (PB) and polyisobutylene (PIB). Polybutene-block-ethylenebutene copolymer (PB-EB) copolymer will serve as the surfactant. This system was chosen on the basis of the temperature dependence of the PB/EB and PIB/EB Flory-Huggins interaction parameters. It is expected that the balancing of PIB-philic and PIB-phobic tendencies of the surfactant will lead to the rich varieties of phase behaviors that have, thus far, only been identified in aqueous mixtures. The principle of balance that is being developed is, however, perfectly general, and can be applied to a wide variety of polymer blends. Model polymers required for this study will be synthesized by anionic and cationic polymerization. Self-assembly will be studied by small angle neutron scattering at the National Institute of Standards and Technology (NIST), light scattering, and electron microscopy.Broader Impact of Proposed Activity and GOALI mechanismThe student working on this project will be jointly advised by the PI (at UC Berkeley) and co-PI (at ExxonMobil). The student will spend about 6 weeks every year, working at the ExxonMobil Corporate Research Labs in Annandale, NJ. All of the expenses associated with the visit (lodging, travel, lab supplies, etc.) will be paid by ExxonMobil. The framework for this collaboration has already been established: the PhD student spent 2 weeks this past summer at ExxonMobil, learning about polymer synthesis, and obtaining safety training and clearances to work in the ExxonMobil Labs. Exposure to an industrial research lab will add a new dimension to the student's education. Since the project will involve several visits to the NIST, the student will learn about the functioning of government laboratories. The materials and samples that will be synthesized and characterized will be used in teaching courses on both thermodynamics and polymer science at Berkeley, and at other institutions such as NIST.

目标：用于高度不混溶聚合物自组装的平衡表面活性剂拟议活性的智力价值拟议工作的目标是建立一个用于控制高度不混溶聚合物混合物中自组装的表面活性剂库。这将使新的纳米结构聚合物材料的创造成为可能。它还可能使混合聚合物废物的再利用成为可能。该方法代表了该领域先前大量实验和理论工作的背离，这些工作依赖于a -B共聚物的表面性来组织a和B均聚物的混合物。现在人们认识到，这些类型的共聚物只有在弱不混相的情况下才能组织界面。研究中使用的表面活性剂是一种平衡的a - c嵌段共聚物。平衡的概念改编自有关水性体系表面性的文献。疏水性和亲水性平衡的非离子表面活性剂虽然具有高度的不相容性，但在油/水混合物中成功地形成了纳米级的组织。本研究涉及这一原理在聚合物中的应用。实验将对高度不混相的聚烯烃、聚丁烯（PB）和聚异丁烯（PIB）的混合物进行。聚丁烯-嵌段乙烯丁烯共聚物（PB-EB）共聚物作为表面活性剂。根据PB/EB和PIB/EB的Flory-Huggins相互作用参数的温度依赖性选择了该体系。预计表面活性剂的亲pib和疏pib倾向的平衡将导致丰富多样的相行为，到目前为止，只在水混合物中发现过。然而，正在开发的平衡原理是完全通用的，可以应用于各种各样的聚合物共混物。本研究所需的模型聚合物将通过阴离子和阳离子聚合合成。自组装将通过美国国家标准与技术研究所（NIST）的小角度中子散射、光散射和电子显微镜进行研究。拟议活动和目标机制的更广泛影响参与该项目的学生将由加州大学伯克利分校的PI和埃克森美孚公司的co-PI共同提供建议。该学生每年将花大约6周的时间，在新泽西州安纳代尔的埃克森美孚公司研究实验室工作。与访问相关的所有费用（住宿，旅行，实验室用品等）将由埃克森美孚公司支付。此次合作的框架已经建立：这位博士生在去年夏天花了两周时间在埃克森美孚学习聚合物合成，并获得了在埃克森美孚实验室工作的安全培训和许可。接触工业研究实验室将为学生的教育增加一个新的层面。由于该项目将涉及几次访问NIST，学生将了解政府实验室的运作。将合成和表征的材料和样品将用于伯克利和其他机构（如NIST）的热力学和聚合物科学教学课程。