In this process, acid groups will need to be more than the epoxy groups such that after consumption of all the epoxy, 2-10% acid groups are left. All the reactive solvent will be grafted onto the acrylic polymer backbone, leaving no free solvent after completion of the monomer polymerization. all the acrylate and methacrylate monomers will be polymerized by the free radicals generated from the dissociation of the initiator (Figure 2). acid groups will react with epoxy groups of the solvent, generating hydroxyl groups and 2. During the addition of the monomer feed, two reactions will take place: 1. One of the co-monomers in the monomer feed will need to be an acid-functional acrylic or methacrylic when epoxy is used as a solvent. These solvents can be heated to their boiling point or to 150-160 ā in case of Cardura E (boiling point 251-271 ā) in the flask into which co-monomers and initiator dissolved in the reactive solvent can be added simultaneously over 3-5 hours. To overcome VOC and waste generation issues, low-Mw acrylic polymer dispersions can be made by using a reactive solvent such as 1,2 epoxy hexane, 1,2 epoxy cyclohexane, 1,2 epoxy octane, or epoxy ester of neodecanoic acid (known as Cardura Eā¢, Figure 1). If the solvent is distilled out from the polymer it will generate undesirable waste. This type of polymer in coatings will release solvent in the atmosphere during application and curing, contributing to the volatile organic compounds (VOCs). Upon completion of the polymerization as judged by consumption of all the monomers, acid groups are partially or completely neutralized with base, and the polymer thus formed is diluted with water. The solvent is heated to its boiling point in the flask, into which a co-monomers feed containing acid-functional acrylic or methacrylic monomer is added simultaneously with the initiator dissolved in organic solvent over 2-5 hours. Low-Mw polymer dispersions are traditionally made in a water-compatible organic solvent. Low molecular weight (weight average molecular weight, Mw 50,000). These dispersions are classified in two broad categories: 1. Waterborne acrylic dispersions are widely used in the production of coating formulations for industrial applications such as automotive, decorative and marine coatings.
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