New Type of Polymer Coating System onto Metal Surface from Polymer Emulsion

众所周知，电沉积在世界范围内被用作在金属表面上涂覆聚合物涂层的技术。最近，我们提出了一种类似的涂覆方法，其中，在不施加电流的情况下，仅通过将该聚合物浸入阴离子聚合物乳液（其pH被调节为低于约3）中，就可以将该聚合物沉积到阳极化铝板上。我们把这种涂覆过程称为“化学沉积”。通过对该技术的一系列基础性研究，指出了该技术在工业应用中存在的一些严重问题。本项目的目的是改善他们，我们成功地做到了以下几点：1。由于使用盐酸调节pH值，导致涂料性能不高。我们尝试用甲酸、丙酸等有机酸来代替它。涂层厚度随着乳液浴重复使用次数的增加而减小。我们可以通过使用一些掩蔽剂来改善该问题，所述掩蔽剂通过每次浸渍从铝板中溶解而积累在其中。3.由于乳化剂分子，特别是游离的乳化剂分子对化学沉积有不良影响，我们不得不使用无乳化剂的聚合物乳液。不含乳化剂的乳液没有良好的长期储存稳定性。将可聚合乳化剂应用于聚合物乳液的制备，可以改善这一问题。

It is well knowen that electrodeposition is used worldwide as a technique for polymer coatings onto a metallic surface. Recently we have proposed a similar coating process in which the oplymer could be deposited onto an anodized aluminum plate without applied electric current only by immersing it into an anionic polymer emulsion the pH of which was adjusted below about 3. We have termed this coating process as "chemical deposition". According to a series of fundamental investigations on it, as pointed in underlines below, there were some serious problems which is required to improve for applying it industrially. The purpose of this project is to improve them and we have succeeded it as follows:1. We had usd hydrochloric acid to adjust the pH. Because of it, the properties of coatings had no high quality. We colud apply some organic acids such as formic acid and propionic acid in place of it. 2. The coating thickness decreased with an increase in the number of repeated use of the emulsion bath. We could improve the problem to use some masking agents for aluminum ions which are accumulated therein by dissolving from the aluminum plate every dipping. 3. We had to use emulsifier-free polymer emulsion, because emulsifier molecules, especially free ones gave a bad influence in the chemical deposition. the emulsifier-free emulsion had no good long storage stability. We could improve the problem by applying a polymerizable emulsifier in the preparation of polymer emulsion.