GOALI: EB Polymerization: Advanced Characterization of Curing Processes and Polymer Materials

摘要提案编号：1264622大学参与者：Julie L. P. Jessop博士，University of Iowa, Iowa City， IA行业参与者：Stephen C. Lapin博士，PCT Engineered Systems， LLC, Davenport， IA题目：目标：EB聚合：固化过程的高级表征和高分子材料的知识价值。与热聚合相比，电子束（EB）固化提供了一种快速、低能耗、无溶剂的聚合油墨、薄膜和涂料的方法。不需要引发剂来形成自由基活性中心，这使得该技术对分子迁移有问题的包装应用特别有吸引力。此外，与光聚合不同，颜料、填料、纤维和纳米材料等添加剂不会阻止电离辐射的渗透，从而产生优异的产品一致性。尽管有这些优点，世界范围内用于固化应用的低能量（100至300千伏）加速器还不到500台。为了增加EB技术的使用，需要改进固化工艺和所得到的聚合物的性能。虽然私营公司已取得一些发展，但仍需要对工艺参数及其影响进行更基本的研究；然而，EB固化的学术研究一直受到限制，部分原因是EB加速器的高费用和有限的获取途径。这一目标将促进工业和学术合作伙伴之间的合作（在辐射化学和聚合物动力学和物理性质的描述方面拥有超过40年的综合经验），以解决EB技术中的这些关键需求。PCT工程系统公司开发和制造BroadBeam低能电子束加速器，位于距该公司不到一小时的距离。从爱荷华大学校园开车。这项研究的目标是通过增加对能量沉积和工艺条件对动力学和材料性能影响的基本理解来推进EB技术。为了实现这一目标，将合作开展以下四个关键主题：(1)比较eb固化和uv固化材料的转化；(2)比较eb固化、uv固化和热固化材料的物理性能；(3)开发很少或不需要氮化的eb固化树脂配方；(4)单体结构与EB剂量率的关系。转换作为深度的函数将使用拉曼共聚焦显微镜来测量，以证明辐射穿透和氮惰化的影响。分子量分布（线性聚合物）、交联密度（聚合物网络）和聚合物模量将使用凝胶渗透色谱和动态力学分析来测量，以证明引发机制、单体结构和工艺参数对聚合物物理性质的影响。将探讨环氧化物/丙烯酸酯和硫醇/丙烯酸酯体系来减轻氧抑制作用。这些研究的结果将提供对eb -固化过程和所得聚合物性能的更好理解。这种理解将有助于将EB技术扩展到更广泛的应用领域，包括高性能材料和三维部件。更广泛的影响。这种对eb -固化过程和由此产生的聚合物材料的高级表征将提供对eb -固化系统的理解水平，大大超出目前可用的水平。这些知识将为扩大EB技术的应用，特别是在薄膜、涂料、粘合剂和复合材料行业的应用提供基础。这项研究的结果将促进美国在EB技术的前沿地位，增加设备和产品的出口机会，并随着EB行业的发展提供新的就业机会。这个研究项目也将对不同层次的学生的教育经历产生直接的影响。工程和科学专业的学生将受益于聚合物科学系列课程，这些课程将纳入本项目的研究成果。几名本科生和高中生将被邀请参与部分研究，两名研究生将集中精力研究这些eb -固化系统。此外，通过既定的征聘和外联战略，将鼓励人数不足的妇女和少数民族参加这项研究。EB技术进步的研讨会将在UI和PCT上举行，EB相关的专题讨论会将在2016年RadTech、2014年光聚合基础知识和ACS全国会议上组织。可衡量的产业协作。PCT将提供EB培训、进入其EB试验线进行治疗研究以及实习机会。PCT还将就行业需求向UI研究人员提供建议，帮助设定项目里程碑和可交付成果，并监测研究进展。Lapin博士将担任研究生委员会的联合顾问，并将协助组织有关EB技术及其使用的地方和国家专题讨论会。

ABSTRACTProposal Number: 1264622University participant: Julie L. P. Jessop, Ph.D., University of Iowa, Iowa City, IA Industry participant: Stephen C. Lapin, Ph.D., PCT Engineered Systems, LLC, Davenport, IA Title: GOALI: EB Polymerization: Advanced Characterization of Curing Processes and Polymer Materials Intellectual Merit. Electron-beam (EB) curing offers a fast, low-energy, and solvent-free means of polymerizing inks, films, and coatings compared to thermal polymerization. No initiator is required to form the free-radical active centers, making this technique especially appealing for packaging applications where molecular migration would be problematic. In addition, unlike photopolymerization, additives such as pigments, fillers, fibers, and nanomaterials do not prevent penetration of the ionizing radiation, resulting in excellent product consistency. In spite of these advantages, less than 500 low-energy (100 to 300 kV) accelerators are installed worldwide for curing applications. In order to increase use of EB technology, improvements are needed in both the curing process and performance properties of the resulting polymers. While some development has occurred among private companies, there is need for a more fundamental study of process parameters and their effects; however, academic research on EB curing has been limited in part by the high expense of and limited access to EB accelerators. This GOALI will facilitate collaboration between industrial and academic partners (with over 40 years combined experience in radiation chemistry and characterization of polymer kinetics and physical properties) to address these critical needs in EB technology. PCT Engineered Systems develops and manufactures BroadBeam low energy EB accelerators and is located less than an hour?s drive from the University of Iowa (UI) campus. The goal of this research is to advance EB technologies by increasing the fundamental understanding of the effects of energy deposition and process conditions on kinetics and material properties. To meet this goal, the following four key topics will be pursued collaboratively: (1) compare conversion of EB-cured and UV-cured materials; (2) compare physical properties of EB-cured, UV-cured, and thermally cured materials; (3) develop EB-cured resin formulations requiring little or no nitrogen inerting; and (4) correlate monomer structure with EB dose rate. Conversions as a function of depth will be measured using Raman confocal microscopy to demonstrate the effects of radiation penetration and nitrogen inerting. Molecular weight distributions (for linear polymers), cross-linking density (for polymer networks), and polymer modulus will be measured using gel permeation chromatography and dynamic mechanical analysis to demonstrate the impact of initiation mechanism, monomer structures, and process parameters on polymer physical properties. Epoxide/acrylate and thiol/acrylate systems will be explored to mitigate oxygen inhibition. The results of these studies will provide an improved understanding of both the EB-curing process and the properties of the resulting polymers. This understanding will facilitate the extension of EB technologies to a wider range of applications, including high-performance materials and three-dimensional parts. Broader Impacts. This advanced characterization of the EB-curing process and the resulting polymer materials will provide a level of understanding of EB-cured systems significantly beyond what is currently available. This knowledge will provide a basis for expanding the applications of EB technologies, especially in the film, coating, adhesives, and composites industries. Results of this research will facilitate establishment of the US at the forefront of EB technologies, increase export opportunities for equipment and products, and provide new jobs as the EB industry expands. This research program will also have a direct impact on the educational experience of students at various levels. Students in engineering and science will benefit from a polymer science course series that will incorporate research results from this project. Several undergraduate and high-school students will be invited to participate in portions of this research, and two graduate students will focus their efforts on investigating these EB-curing systems. Furthermore, through established recruitment and outreach strategies, underrepresented females and minorities will be encouraged to participate in this research. Seminars on EB technology advancements will be held at the UI and PCT, and EB-related symposia will be organized at RadTech 2016, Photopolymerization Fundamentals 2014, and ACS national meetings. Measurable Industrial Collaboration. PCT will provide EB training, access to its EB pilot line for curing studies, and internship opportunities. PCT will also advise UI researchers on industry needs, help set project milestones and deliverables, and monitor the progress of the studies. Dr. Lapin will serve as a co-advisor for the graduate student committees and will assist in organizing local and national symposia relating to EB technology and its use.