Eastman polyolefin adhesion promoters consist of modified polypropylene and polyethylene polymers that are used to improve adhesion to untreated plastics and other difficult to bond surfaces. These adhesion promoters can be used to improve adhesion in three ways; as a primer between the substrate and subsequent coating, as a primer or tie coat between coating layers, and as a stir-in additive to the formulation. Eastman polyolefin adhesion promoters can be categorized into one of two product categories; chlorinated polyolefins and non-chlorinated polyolefins.
Chlorinated polyolefin adhesion promoters are polyethylene and polypropylene polymers that have been modified with chlorine. When used as a primer, the olefin backbone of the polymer bonds well to untreated, non-polar substrates and functions as a coupling agent between the substrate and polar functional groups present in subsequent coatings, paints, inks, or adhesives. In addition to use as a primer, grades of chlorinated polyolefins with a high chlorine content can be added directly to formulation as an adhesion-promoting additive to create a one step topcoat system with enhanced adhesion properties. In addition to enhanced adhesion to olefin based plastics, chlorinated polyolefins can be used to improve adhesion performance to metal, polyvinyl chloride, and other non-olefin plastics.
Non-chlorinated polyolefin adhesion promoters are polypropylene and polyethylene polymers that are modified with functional groups other than chlorine, in most cases maleic anhydride. These adhesion promoters should be used when halogens need to be avoided for regulatory or environmental concerns. These chlorine-free polymers function similar to the chlorinated polyolefins and can improve adhesion when used as a primer or formulated directly in a coating, ink, or adhesive.
Eastman Polyolefin Adhesion Promoters are commercially available as solutions, water-based dispersions, and as solid resins. Solution based grades are available in multiple solvents including xylene and aromatic 100. The solution grades are ideal for use in solvent-based coating systems. If solvent must be avoided, the water-based dispersion grades are recommended. To learn more about a specific chlorinated or non-chlorinated polyolefin adhesion promoter select a grade page below, contact us today to speak to one of our product experts, or click here to view our detailed how to guide.