We all know that additives impart critical properties to a coatings formulation, but we seldom focus on those properties and tend to forget the major role that additives play. Our attention is usually centered on the major compositional materials in a coating - the polymers, pigments and the solvent if formulating a liquid coating. We use additives to fine-tune formulas, to provide better application properties, and to correct for a problem that has arisen because of a prior improper use of another additive.
Considering that additives are used in rather miniscule quantities, they can cause major coating problems if not used properly - and when used properly can provide tremendous properties. It is amazing the characteristics they provide considering the small quantities that are used. Some of them are so multifunctional that it is difficult to grasp their true nature.
The key to formulation is to understand the function of an additive in terms of its chemical or physical nature and behavior in the presence of other components in the coatings formulation. Without a doubt it is much easier said than done. Many of our additives are just used as "trade names" and we often don't even know much about their chemical composition or how they might behave - or misbehave - in a given formulation. A majority of the coatings failure problems that I have encountered throughout my career can be laid at the doorstep of an additive that has been misused.
Each year we have been adding more information to the Additives Guide (contained in this issue of PCI), so that it will provide a superb source of concise information regarding additives. The growth in nanotechnology poses a problem with respect to this guide, as it is not so simple to categorize and know where to include this technology. We have added a section called nanotechnology and cross-referenced it to other areas.
The raw material suppliers are very good at helping formulators and providing them guidelines with respect to the materials they provide. The problem, however, is that a single-source guide is needed. That is our intent in providing this issue. The authors of this guide were not fortunate enough to have such a resource available in our ‘younger' days. Hopefully, much of what we have learned from our own experience and what we have culled together in this guide will be of aid to the coatings industry today. This guide will also be available for purchase on a CD.