Polyacrylate Polyols

Polyacrylate polyols are oligomeric polyols synthesized from hydroxyl-free acrylates and hydroxyl-containing acrylates or allyl alcohol.

Polyacrylate polyols are mainly used in light-resistant, anti-chalking, and weather-resistant acrylic-polyurethane coatings, for applications such as outdoor coatings and automotive paints. The acrylic polyurethane coatings produced by the reaction of polyacrylate polyols with polyisocyanates are hybrid polymers, combining the light resistance of polyacrylates with the formulation flexibility and rapid curing characteristics of polyurethanes. The resulting coatings exhibit excellent weather resistance, abrasion resistance, and chemical resistance. These polyacrylate polyols are mainly used with aliphatic polyisocyanates or melamine-based crosslinkers to formulate two-component automotive coatings, maintenance and refinishing coatings, and industrial coatings.

Polyacrylate polyols synthesized from hydroxyl-free acrylates and hydroxyl-containing acrylates (such as hydroxyethyl acrylate) generally have randomly distributed hydroxyl groups. These polyacrylate polyols have high viscosity and are usually produced by solution polymerization in a solvent and supplied in solution form.

Rohm & Haas’s Paraloid AU series of polyacrylate polyols, a subsidiary of Dow Chemical Company, are mainly used in acrylic polyurethane repair and industrial coatings. Most products offer the following advantages: low isocyanate consumption, reducing costs; enabling the formulation of low-VOC coatings; fast drying; high gloss; excellent durability; and excellent corrosion and chemical resistance. Typical physical properties and characteristics of most Paraloid AU series products are shown in Table 4-2. The company also offers Paraloid AU-191X high-solids polyacrylate polyol and AU-1164S solvent-based polyacrylate polyol resin, both used in polyurethane acrylate coatings. Placcel EPA and Placcel DC series polyols from Daicel Corporation (formerly Daicel Chemical Industries, Ltd.) of Japan are caprolactone-modified polyacrylate polyols. They are obtained by polymerizing caprolactone-modified acrylate macromonomers, which are synthesized using hydroxyalkyl (meth)acrylate as an initiator. The hydroxyl groups in this resin are far from the acrylate main chain, resulting in high reactivity. They can be combined with polyisocyanate crosslinkers such as HDI biuret to form two-component coating resins, creating elastic polyurethane coatings.

Other manufacturers and products of acrylic polyols include: RA series from Procachem Corporation (Taiwan), Macrynal SM series from Cytec Industries (USA), KP series from KS Chemical Co., Ltd. (South Korea), Disvacryl series from D.S.V Chemicals Pvt Ltd (India), Drokryl series from D.R. Coats Ink & Resins Pvt.Ltd. (India), Hardcastle & Waud Mfg Co.Ltd. (India), and Synocure series from Cray Valley (France), among others.