Chlorinated modified polyolefins (CMPOs) are primarily used in solvent-based systems as primers or additives for coatings that need to adhere to low-surface-energy plastic substrates like polypropylene, polyethylene, PET and many others. Non-chlorinated modified polyolefins (NCMPOs) are used for similar applications as the CMPOs, but they have the added benefit of higher chemical and temperature resistance, and they are colorless. NCMPOs are also used in applications where chlorine cannot be tolerated because of potential production of hydrochloric acid when exposure to high temperatures occurs. In Figure 1 the basic structure of an NCMPO is shown. The polyolefin backbone on the polymer allows for better wetting and surface bonding to polyolefin surfaces because of Van der Waals forces. The modification on the polymer allows for potential reactions with reactive groups in resins and for interactions and bonding with inorganic substrates. The structure of the NCMPO allows it to bond to polyolefin and non-polyolefin substrates.
In the last few years there has been a trend in using polyolefin substrates for different applications like roofing and flooring because of raw material costs of using polyolefins versus other plastics. Polyolefins are also being used because of their desirable physical properties and their recyclability potential. There are many applications in which polyolefins could be used, but they are not because there are not practical ways to adhere them to where they need to be placed because of their low surface energy. Polyolefins are often corona or flame treated to increase the surface energy to make them easier to adhere to. Sometimes corona treatment and flame treatment are not enough to make the substrates easier to bond to. So, CMPOs and NCMPOs are used to increase the adhesion to the olefin substrates as adhesion promoters, but they are often used in solvent-based products to achieve the necessary adhesion. There are many applications were solvents cannot be tolerated, and corona and flame treatment are too expensive to do. In this work, we used our waterborne NCMPO emulsions the AdvaBond
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7400 series adhesion promoters in three different applications to show how they can be used to adhere to polyolefin substrates without the use of harsh solvents and surface modifications, and how they can improve the adhesion to non-polyolefin substrates. The first being a waterborne membrane adhesive, the second a waterborne flooring adhesive, and the last a general caulk/sealant adhesive.