Poly just means "many" as in repeating units. That is what a Poly-mer is. Using Poly to refer to any particular polymer is like saying things that fly. Does that mean birds? Planes? Kites?
Enough of semantics. Now to the chase. The backbone of the polymer will determine the ultimate properties that can be achieved. While it is true that polyesters will have one general set of attributes while polyurethane or polysaccharides will have others, there is a great spread in properties that naming the polymer does not really help to figure out what the performance is.
If forced to categorized finishes, I would most likely have to call them linear or branched. An example of linear is nitrocellulose lacquer. A property of some linear polymers is that they can be dissolved in solvents and applied that way. Branched polymers do not dissolve so they have to be cured in place. So one attribute that is clear is that nitrocellulose is linear so it can more easily be affected by other solvents that might come in contact with the coated surface. Branched polymers tend to be more resistant to solvents.
There is more but I suspect people have already stopped reading this post at this point because it is too technical so I will stop here.
Frank Sanns
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