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. P.M.，博士，爱荷华州大学，爱荷华州爱荷华州市，IA行业参与者：Stephen C. Lapin博士，PCT Engineered Systems，LLC，Davenport，IA标题：GOALI：EB聚合：固化过程和聚合物材料的高级表征知识产权。与热聚合相比，电子束（EB）固化提供了一种快速、低能量和无溶剂的聚合油墨、薄膜和涂料的方法。不需要引发剂来形成自由基活性中心，使得这种技术特别适合于分子迁移会有问题的包装应用。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，从而获得优异的产品一致性。尽管有这些优点，但全世界安装的用于固化应用的低能量（100至300 kV）加速器不到500台。为了增加EB技术的使用，需要改进固化过程和所得聚合物的性能。虽然在私营公司中取得了一些进展，但仍需要对工艺参数及其影响进行更基础的研究;然而，EB固化的学术研究部分受到EB加速剂的高成本和有限获取的限制。该GOALI将促进工业和学术合作伙伴（在辐射化学和聚合物动力学和物理特性表征方面拥有超过40年的综合经验）之间的合作，以满足EB技术的这些关键需求。PCT工程系统开发和制造BroadBeam低能量EB加速器，位于不到一个小时？从爱荷华州大学校园开车过来。本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的影响的基本理解来推进电子束技术。为了实现这一目标，将共同研究以下四个关键课题：（1）比较EB固化和UV固化材料的转化率;（2）比较EB固化、UV固化和热固化材料的物理性能;（3）开发需要很少或不需要氮气惰性化的EB固化树脂配方;（4）将单体结构与EB剂量率相关联。将使用拉曼共聚焦显微镜测量作为深度的函数的转化率，以证明辐射穿透和氮气惰性化的影响。将使用凝胶渗透色谱法和动态力学分析测量分子量分布（对于线性聚合物）、交联密度（对于聚合物网络）和聚合物模量，以证明引发机制、单体结构和工艺参数对聚合物物理性能的影响。将探索环氧化物/丙烯酸酯和硫醇/丙烯酸酯系统以减轻氧抑制。这些研究的结果将使人们更好地了解EB固化过程和所得聚合物的性能。这种理解将促进电子束技术扩展到更广泛的应用，包括高性能材料和三维零件。更广泛的影响。这种先进的表征电子束固化过程和所产生的聚合物材料将提供一个电子束固化系统的理解水平显着超出目前可用的。这些知识将为扩大电子束技术的应用提供基础，特别是在薄膜，涂料，粘合剂和复合材料行业。这项研究的结果将促进美国在电子束技术的前沿，增加设备和产品的出口机会，并随着电子束行业的扩大提供新的就业机会。这项研究计划也将对各级学生的教育经验产生直接影响。工程和科学专业的学生将受益于聚合物科学系列课程，该课程将结合该项目的研究成果。一些本科生和高中生将被邀请参加本研究的部分，两名研究生将集中精力调查这些电子束固化系统。此外，将通过既定的征聘和外联战略，鼓励代表性不足的妇女和少数群体参与这项研究。关于电子束技术进步的研讨会将在UI和PCT举行，电子束相关的专题讨论会将在RadTech 2016、Photopolymerization Fundamentals 2014和ACS国家会议上组织。可衡量的工业合作。PCT将提供EB培训，进入其EB试点线进行固化研究，并提供实习机会。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交付成果，并监控研究进展。Lapin博士将担任研究生委员会的联合顾问，并将协助组织与EB技术及其使用有关的地方和国家研讨会。

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.