TELECHELIC POLYMERS - PRECURSORS TO HIGH SOLIDS COATINGS

Coating industry concerns for energy and environmental cost in formulation suggest high solids coatings as an alternative. The use of 100% active coatings, wherein the polymeric binder precursor has functional groups on the chain ends, is rationalized. However, the use of liquid 'telechelic' polymer requires the knowledge of syntheses for understanding of fluid properties, cures and physical properties after cure. Synthesis techniques control these end results through their influence on type and amount of functionality, chain configurations and by-products. As the techniques for making carboxy- or hydroxy-telechelic polyesters or hydroxy-telechelic polyethers have been the object of considerable study and review, this review deals with syntheses based upon addition polymers. The synthesis methods' impact on functionality (type and amount) is emphasized. Fluid property expectations are also noted, and analysis techniques summarized. Currently commercial polymers are cited with notation as to recommended cure and uses. A Summary of cure studies, mostly with emphasis on the applications (e.g. rocket propellant binders, sealants, coatings and so on) is also included. The conclusions are that current problems with rheology, cure rates and chemistry, and final coating properties may be overcome by appropriate research. These efforts are already under way in some segments of the industry, and high solids coatings or 100% active coatings will be a growing factor in the market place. The prime objective of this review is to gather some of the pertinent information on synthesis, properties and application of the telechelic polymers as a guide to the research on high solids coatings. © 1979.