Next-generation super varnishes via reversible de-activation radical polymerization

涂层是汽车和航空航天工业中使用的材料不可或缺的组成部分。在这个竞争激烈的行业，C&D Aerospace Canada Co.（C&D Zodiac Inc.的子公司）认为至关重要的是开发自己的清漆涂料配方：超级清漆。 明显的“必备”特性包括抗开裂、防止收缩、高阻燃性和对木材基材的粘附性。 此外，涂层溶液必须适合于喷涂技术，并且必须具有延长的保质期。 通过我们之前的相互作用，我们已经开发出一种具有高树脂含量（30%重量）但粘度非常低的配方，从而降低了挥发性有机物含量（VOC）。 它还将几种性质结合到一个单一分子中。 除了满足最初的要求外，超级清漆开发的下一步是开发更环保的工艺，进一步减少VOC（从而提高阻燃性能）和自愈特性。 更环保的工艺不仅包括通过水性涂料工艺减少VOC，还包括尽可能多地使用来自可持续资源的单体。 可逆失活自由基聚合（RDRP）的使用使得能够更精细地控制微观结构以及在分散的水性体系中容易聚合的能力。自修复特性是期望的，因为恢复和封闭任何表面损伤/缺陷的材料消除了昂贵的划痕去除程序。RDRP在自修复材料中的应用是最前沿的，只有最近的报道才强调了这种新颖的组合。通过整合所有这些功能，这些新型树脂涂层的工程设计（多重涂层，热处理，对流干燥）将确保优化材料性能和工艺时间，从而实现轻松的工业实施。

Coatings are integral for materials used in the automotive and aerospace industries. In this competitive sector, C&D Aerospace Canada Co. (subsidiary of C&D Zodiac Inc.) considers it vital to develop their own varnish coating formulations: a super varnish. Obvious "must-have" properties include resistance to cracking, prevention of shrinkage, high anti-flammability and adhesion to wood substrates. Further, the coating solution must be amenable to spraying techniques and must have an extended shelf-life. Through our previous interactions, we have developed a formulation that has high resin content (30% be weight) but has very low viscosity, thereby reducing the volatile organic content (VOC). It also combines several properties into one single molecule. In addition to meeting the initial requirements, the next step towards the development of a super varnish would be to develop greener processes with further reduction in VOC (which leads to improved anti-flammability properties) and self-healing characteristics. Greener processes includes not only reduction in VOC via water-borne coating processes, but also incorporating monomers from sustainable resources as much as possible. The use of reversible de-activation radical polymerization (RDRP) enables finer control of microstructure plus the ability to be readily polymerizable in dispersed aqueous systems. Self-healing properties are desirable, as materials that revert and close any surface damage/defect eliminates costly scratch-removal procedures. The application of RDRP to self-healing materials is cutting-edge, with reports only relatively recently highlighting this novel combination. With the incorporation of all these features, engineering of these novel resin coatings (multiple coatings, heat treatments, convective drying) will ensue to optimize material properties and process time, leading to a facile industrial implementation.