Tackifier waterborne

A second generation of phenolic dispersions, patented by J. S. Fry (33). involved the post dispersion of phenolic resins in a mixture of water and water-miscible solvents. To conform with air pollution regulations, the solvent was held to 20 volume %, or less, of the volatiles. A heat-reactive phenolic resin dispersion (34) and a phenolic-epoxy codispersion have become commercially available based on the above technology. Supplied at 40-45% solids, these products, which have a small particle size (0.75-1.0 ym), are better film formers than the earlier dispersions. Used alone or in blends with other waterborne materials, corrosion-resistant baking coatings may be formulated for coil coating primers, dip primers, spray primer-surfacers, and chemically resistant one-coat systems. Products of this type are also tackifiers for acrylic latexes, and such systems have been employed as contact, heat seal, and laminating adhesives for diverse substrates. 

As discussed in the Introduction, in addition to hot-melt adhesives, one of the most important forms of adhesives for the future is the waterborne system. In general, an advantage of the waterborne system is that it is free from the solvent-pollution problem. For this reason, we shall describe several new waterborne systems in detail acrylics, modified ethylene-vinyl acetate, polyurethanes, phenolics, epoxies, isocyanates, and tackifiers. Applications of these systems range from PSA s contact adhesives, and laminating adhesives to wood adhesives. 

For PSA s with the resin-rubber systems, several types of latexes are being used in place of rubber for the waterborne adhesives. Styrene-butadiene (102) latexes and natural rubber latexes (103) have been mentioned in the literature. In addition, waterborne tackifiers (104) have been developed for PSA s. A family of emulsifier-free, high solids, completely freeze-thaw stable tackifying resins was developed by Rohm and Haas. The new products are viscous resins based on the replenishable tail-oil rosin. The... 

Phenolic tackifiers (106) in the form of dispersions can be used to formulate neoprene or acrylic latex into waterborne contact adhesives. For example, a solid ratio of latex and phenolic dispersion (Union Carbide-BKUA-2370 or BKUA-2260)of 3 1 can form a stable adhesive at pH 6.0-6.5. 

Uses Tackifier for adhesives inci. food-pkg. adhesives, environmentaiiy friendiy adhesives, carboxyiated SBR, 2-ethyihexyi acryiate, butyi acryiic, SBR, NR, neoprene, VAE, urethane systems defoamer in food-contact paper/paperboard Features Waterborne provides improved aging props., enhanced adhesive props. Reguiatery FDA 21CFR 175.105,176.210 Properties Vise. 7000 cps soften, pt. (R B) 85 C pH 7.0 60% soiids... 

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