GOALI - Fundamental Studies of Microstructure and Property Development in Novel Latex Coatings

GOALI - 新型乳胶涂料微观结构和性能发展的基础研究

• 批准号: 0967348
• 负责人: Lorraine Francis
• 金额: $ 31.42万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-15 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0967348&HistoricalAwards=false
• 关键词: GOALI; Fundamental; Studies; Microstructure; Property

Intellectual Merit: This collaborative research explores the fundamentals of microstructure and property development in coatings created from engineered latex particles developed at Arkema, Inc. Arkema is a leading supplier of specialty chemicals that are used in the coatings industry and has been an innovator in the development of synthetic routes to new latex particles. The University of Minnesota has developed advanced techniques to monitor structure and property development in situ during drying and via time sectioning methods in which the coating is frozen at different stages of structure development and then examined in the frozen state by cryogenic scanning electron microscopy (cryoSEM). The overall aim of the research is to advance the understanding of the film formation and structure development in latex coatings using model systems that are industrially relevant and well suited to fundamental research. Two novel latex systems will be explored in this research: (1) block copolymer latex and (2) fluoropolymer acrylic latex. The block copolymer latex consists of nanostructured particles with a combination of hard and soft blocks in a microphase separated nanostructure. The role of this nanostructure on film formation is not understood. The objective of this part of the research is to connect the nanostructure of block copolymer latex particles with the film formation process and the final structure of the coating. Model block copolymer latex with a range of chemistries and morphologies will be synthesized at Arkema. CryoSEM will be used to track the development of structure during film formation so that connections to nanostructure can be made. The stages in structure development, from discrete particles through compaction and deformation to the final coalesced film, will be imaged in frozen specimens. AFM studies will complement the research. With the fluoropolymer-acrylic latex, the main objective is to characterize film formation and relate the structure development to stress and cracking. Understanding and controlling cracking is important to the application of latex materials. Arkema will provide model materials formulated with and without a coalescing aid. CryoSEM studies will be carried out in parallel with measurements of weight loss and stress development and observations of cracking in order to determine the origin of the stress that causes cracking and the role of the latex particle structure on the phenomenon. The second objective is to use a broader set of particles to explore connections between particle and process parameters on cracking, and ultimately to develop strategies to mitigate cracks.Broader Impacts: This research will impact the fields of coating processing, colloidal science, materials characterization, and particle mechanics. The results will broadly apply to other latex materials, feeding a growing effort in industry to replace solvent based polymer coatings with water-based latex coatings. The research will help to advance the scientific understanding so that companies can meet the challenges they face as they seek to improve the environment. The impact of the research will extend to multiple groups of students. First, the research will help the career development of the graduate student as well as the undergraduate researchers, who will join the effort in the summers. These students will learn not only from the research itself but also from the interactions with academic and industrial scientists. Second, the graduate students in the home department of the academic PIs will have the opportunity to participate in an industrial roundtable that involves the Arkema PIs. Third, a new experiment will be designed for an undergraduate course in Materials Processing. The students will design coating formulations to make a Cool Roof? using the fluoropolymer acrylic latex. Lastly, the PIs will develop a learning module that introduces K-12 students to engineering concepts, an important topic in light of recent changes to the science standards in the State of Minnesota. The module will also be built on basic concepts in film formation and will include engineering of a Cool Roof. A high school science teacher will join the team to help with the research and the development of the learning module. The Arkema Foundation will make the learning module available through its summer program for science teachers.

智力优势：这项合作研究探索了由阿科玛公司开发的工程乳胶颗粒制成的涂料的微观结构和性能开发的基础原理。阿科玛是涂料行业使用的特种化学品的领先供应商，并且一直是新型乳胶颗粒合成路线开发的创新者。明尼苏达大学开发了先进的技术，可以通过时间切片方法在干燥过程中原位监测结构和性能的发展，其中涂层在结构发展的不同阶段被冷冻，然后通过低温扫描电子显微镜（cryoSEM）在冷冻状态下进行检查。该研究的总体目标是使用工业相关且非常适合基础研究的模型系统，增进对乳胶涂料成膜和结构发展的理解。 本研究将探索两种新型乳胶体系：（1）嵌段共聚物乳胶和（2）含氟聚合物丙烯酸乳胶。嵌段共聚物胶乳由纳米结构颗粒组成，该颗粒在微相分离的纳米结构中具有硬嵌段和软嵌段的组合。这种纳米结构对成膜的作用尚不清楚。这部分研究的目的是将嵌段共聚物乳胶颗粒的纳米结构与成膜过程和涂层的最终结构联系起来。阿科玛将合成具有一系列化学成分和形态的嵌段共聚物乳胶模型。 CryoSEM 将用于跟踪薄膜形成过程中结构的发展，以便建立与纳米结构的连接。结构发展的各个阶段，从离散颗粒到压实和变形，再到最终聚结的薄膜，都将在冷冻样本中成像。 AFM 研究将补充该研究。对于含氟聚合物丙烯酸乳胶，主要目的是表征成膜并将结构发展与应力和开裂联系起来。了解和控制裂纹对于乳胶材料的应用具有重要意义。 阿科玛将提供使用或不使用成膜助剂配制的模型材料。冷冻扫描电镜研究将与重量损失和应力发展的测量以及裂纹的观察同时进行，以确定导致裂纹的应力来源以及乳胶颗粒结构对该现象的作用。第二个目标是使用更广泛的颗粒来探索颗粒与裂纹过程参数之间的联系，并最终制定减轻裂纹的策略。更广泛的影响：这项研究将影响涂层加工、胶体科学、材料表征和颗粒力学领域。研究结果将广泛适用于其他乳胶材料，推动业界越来越多地努力用水性乳胶涂料取代溶剂型聚合物涂料。 该研究将有助于增进科学认识，使企业能够应对在寻求改善环境时面临的挑战。 该研究的影响将扩展到多个学生群体。首先，这项研究将有助于研究生和本科生研究人员的职业发展，他们将在暑期加入这项工作。这些学生不仅将从研究本身中学习，还将从与学术和工业科学家的互动中学习。其次，学术 PI 所在部门的研究生将有机会参加阿科玛 PI 参与的工业圆桌会议。第三，将为材料加工本科课程设计一个新的实验。学生们将设计涂料配方来制作凉爽的屋顶？使用含氟聚合物丙烯酸乳胶。最后，PI 将开发一个学习模块，向 K-12 学生介绍工程概念，鉴于明尼苏达州科学标准最近的变化，这是一个重要的主题。该模块还将建立在成膜的基本概念之上，并将包括冷屋顶工程。一名高中科学老师将加入该团队，帮助研究和开发学习模块。阿科玛基金会将通过其科学教师暑期项目提供该学习模块。