Atmospheric Pressure Plasma Processing of Polymers: Plasma Dynamics and Nanoscale Plasma-Surface Interactions

项目概述常压等离子体处理聚合物：等离子体动力学和纳米级等离子体表面相互作用这是一个计算研究项目，研究聚合物的常压等离子体（APP）传输和等离子体表面相互作用的基础。该计划的目标是建立一个集成的、多尺度的模型层次，跨越纳米到厘米的尺度，并利用它来确定限制等离子体传输过程和高价值材料的APP加工的上升潜力。这些目标是通过开发一个全面的，三维的大气压电晕和辉光放电等离子体动力学模型来实现的，该模型能够研究复杂的等离子体化学；开发三维等离子体表面相互作用算法，能够解决通常在聚合物上发现的纳米级空间结构；适应特征轮廓模型（最初为半导体加工开发），以解决等离子体引发的聚合物表面化学；并将这些模块整合到厘米到纳米的层次结构中。利用等离子体产生所需的聚合物表面特性，如疏水性或亲水性，是当前科学研究和商业利益的一个主题。实现这种功能化的途径有两种：沉积和改性。在等离子体沉积中，通过从等离子体沉积材料获得具有特定特性的聚合物表面。这些过程通常在低压下进行，与用于微电子制造的系统没有什么不同。因此，这种加工通常仅限于高附加值材料，例如生物相容性涂层。在等离子体改性中，用等离子体处理传统制造的廉价聚合物以改变其表面特性。这些过程通常在常压下进行，使用“网”布置的电晕放电装置。与低压等离子体沉积不同，聚合物的常压等离子体加工通常是一个低附加值的过程。聚合物和塑料，如聚丙烯和聚乙烯的加工，以提高其附着力和润湿性。尽管app用于处理聚合物的商业用途，但很少有一阶的、基于基本原理的模型来描述修饰聚合物表面的等离子体表面相互作用。因此，用于聚合物加工的APP的开发和优化，对于所有实际目的来说，都是一项经验主义的事业。更广泛的影响：能够适应廉价和大批量的APP方法来修饰聚合物以生产高价值薄膜的经济和社会效益是惊人的。例如，用于治疗烧伤患者的生物相容性人造皮肤可以以每平方米1美元的价格生产，而不是每平方米1000美元到10000美元的价格，这是fda批准的新产品的典型价格。目前的知识库不足以实现这些进步，而改进知识库将有助于确定实现这些目标的实用性。在这个项目中产生的计算技术和知识库的改进适用于各种APP应用，包括照明、有毒气体修复、表面消毒、生物修复和微排放。

Project SummaryAtmospheric Pressure Plasma Processing of Polymers: Plasma Dynamics and Nanoscale Plasma Surface InteractionsThis is a computational research program that investigates fundamentals of atmospheric-pressure plasma (APP) transport and plasma-surface interactions in the context of APP processing of polymers. The goals of this program are an integrated, multi-scale modeling hierarchy, spanning scales of nanometers to centimeters, and its use to determine the limiting plasma transport processes and upside potential of APP processing of high-value materials. These goals are met by developing a comprehensive, 3-dimensional plasma-dynamics model for atmospheric-pressure corona and glow discharges that is capable of investigating complex plasma chemistries; developing 3-d plasma-surface interaction algorithms capable of addressing the nanoscale spatial structures typically found on polymers; adapting feature-profile models (originally developed for semiconductor processing) to address plasma-initiated chemistry on polymer surfaces; and integrating these modules into a centimeter-to-nanometer hierarchy.The use of plasmas to produce desired surface properties of a polymer, such as hydrophobicity or hydrophilicity, is a topic both of current scientific investigation and of commercial interest. There are two pathways to achieve this functionalization: deposition and modification. In plasma deposition, polymeric surfaces with specific characteristics are obtained by depositing materials from a plasma. These processes are usually performed at low pressures in systems not unlike those used for microelectronics fabrication. As a consequence, such processing is usually limited to high-value-added materials, such as for biologically compatible coatings. In plasma modification, a conventionally manufactured inexpensive polymer is treated with a plasma to change its surface properties. These processes are typically conducted at atmospheric pressure using corona discharge devices in a "web" arrangement. Unlike low-pressure plasma deposition, APP (atmospheric pressure plasma) processing of polymers is usually a low-value-added process. Polymers and plastics such as polypropylene and polyethylene are processed to improve their adhesion and wettability. In spite of the commercial use of APPs for treating polymers, there are few first order, fundamentals-based models describing the plasma-surface interactions that modify polymer surfaces. As a consequence, the development and optimization of APPs for polymer processing has been, for all practical purposes, an empirical undertakingBroader Impacts The economic and societal benefits of being able to adapt inexpensive and high-volume APP methods for modifying polymers to produce high-value films is staggering. For example, biocompatible artificial skin for treatment of burn patients could be produced for $1/m2 as opposed to $1,000's to $10,000's per m2 which is typical of newly FDA-approved products. The current knowledge base is inadequate to make these advances and improving that knowledge base will help determine the practicality of achieving these goals. The computational techniques and improvements in the knowledge base produced in this project are applicable to a variety of APP applications, including lighting, toxic gas remediation, sterilization of surfaces, bioremediation, and microdischarges..