Polymerization by the action of atmospheric oxygen (autoxidation) is curing, b/c its a process of reacting monomer molecules together in a chemical reaction to form three-dimensional networks or polymer chains. There are many forms of polymerization and different systems exist to categorize them, oxidative crosslinking, catalyzed polymerization, and coalescence.
NOT CATALYST/HARDNER or Chemical recation to bond the molecurles together - NO CURING
AIR DRY PAINT - NEVER CURES, BUT ONLY "DRIES"
Definition of CURING & DRYING taken from my PPG Product Training Manual (Did I mention I'm a Level 5 Master Refinishing Technician?):
"At its most basic, curing of a paint is when it turns from a pliable state to a solid state throughout, not just "dry". Curing of paint is not the same as drying as it's a change at chemical level, not merely the evaporation of liquid or binder from the paint. *Note that drying and curing are two different processes. Drying refers to evaporation of solvents, whereas Curing refers to polymerization of the binder. Depending on chemistry and composition, any particular paint may undergo either, or both processes. Thus, there are paints that dry only, those that dry then cure, and those that do not depend on drying for curing.Paints that dry by simple solvent evaporation contain a solid binder dissolved in a solvent; this forms a solid film when the solvent evaporates, and the film can re-dissolve in the solvent again. Classic nitrocellulose lacquers fall into this category. Paints that cure by catalyzed polymerization are generally two package coatings that polymerize by way of a chemical reaction initiated by mixing resin and hardener [/color], and which cure by forming a hard plastic structure. Depending on composition they may need to dry first, by evaporation of solvent. Classic two part epoxies or polyurethanes would fall into this category."
