Organic thin films from novel plasma processes for improved adhesion of composite materials

涉及聚合物薄膜的几个工业过程包括基于大气压冷等离子体（作为放电产生的电离气体）的表面活化步骤。它们涉及通常被称为“电晕”或“介质阻挡放电”处理装置，通过电离空气产生反应性化学物质。这些物质可以与聚合物表面发生反应，导致极性官能团与表面形成共价键。这种工艺可以促进聚合物表面与水或极性溶剂为基础的油漆和胶水的润湿，否则将难以均匀地应用。由于与大气压下的工业等离子体工艺相关的限制，在过去的几十年里，这些工艺几乎没有显著的改进。近年来，常压等离子体技术是一个非常活跃的研究领域，目前已经有了一些成熟的工业应用。我们的实验室一直在开发大气压等离子体技术沉积的薄有机涂层，用于各种应用，现在有广泛的方法沉积各种类型的涂层。特别令人感兴趣的是由高度稀释的乙烯在氮气或空气中沉积的涂层，这是一种相对便宜且无毒的混合物。在与我们的工业合作伙伴CGT公司的初步合作中，我们研究了等离子沉积有机涂层的使用，以改进他们的两个工艺：1)聚丙烯泡沫层压到聚氯乙烯薄膜上；2)热塑性烯烃薄膜上应用表面处理聚氨酯涂层。虽然我们没有成功实现第一个目标，但我们成功地制备了有机涂层，成功地促进了聚氨酯面漆的附着力。然而，这些涂层是通过低压等离子体工艺沉积的，在CGT的生产线上实施是昂贵的。本项目旨在开发一种常压等离子体方法来制备性能良好的类似涂层。成功的开发将给我们的合作伙伴带来明显的竞争优势。

Several industrial processes involving polymer films include a surface activation step based on an atmospheric pressure cold plasma (an ionized gas produced as an electrical discharge). They involve devices commonly know as "corona" or "dielectric barrier discharge" treaters which create reactive chemical species by ionizing air. These species can react with polymer surfaces resulting in the covalent bonding of polar functional groups to the surface. Such processes can promote the wetting of polymer surfaces with water or polar solvent based paints and glues, which would otherwise be difficult to apply homogeneously. Due to the constraints associated with industrial plasma processes at atmospheric pressure, these have seen little significant improvement over the last decades. In recent years, atmospheric pressure plasma technology has been a very actively researched field and several developments are now ripe for industrial application. Our laboratory has been developing thin organic coatings deposited by atmospheric pressure plasma technology for various applications and now has a wide array of methods for depositing various types of coatings. Of particular interest are coatings deposited from highly diluted ethylene in nitrogen or air, a mixture that is both relatively inexpensive and non-toxic. In an initial collaboration with our industrial partner, CGT inc., we investigated the use of plasma deposited organic coatings to improve two of their processes: : i) lamination of polypropylene foam to polyvinyl chloride films and ii) application of a top finish polyurethane coating to thermoplastic olefin film. While we were unsuccessful in achieving the first objective, we were successful in preparing organic coatings that would successfully promote the adhesion of the polyurethane top-finish. Those coatings were however deposited by a low-pressure plasma process that would be expensive to implement in CGT's production line. This project aims at developing an atmospheric pressure plasma method to prepare coatings analogous that were found to perform well. A successful development would give our partner a clear competitive advantage.