11 августа, 2015 
Malyar Alkoxy ether extended polyols, such as propoxylated glycerol, propoxylated and ethoxylated trimethyol propane, have long been used to plasticise acrylamide based acrylics. Where durability is not important, additions of up to 10%, based on solid resin, to a high styrene level acrylic, result in a significant increase in flexibility with little sacrifice in hardness and stain resistance. It is more cost effective to externally plasticise the acrylic copolymer than internally, using a comonomer such as ethyl or butyl acrylate. Suitable polyols for use in acrylics are the Caradol range from Shell Chemicals or the Pluracol range from Wyandotte Chemicals.
Polyols derived from є-caprolactone can be used as reactive diluents to enhance both application solids and performance of hydroxy/acrylic melamine enamels(4 These polyols (Tone® from Union Carbide and Capa® from Interox) have the following features:
• Primary hydroxyl functionality and therefore good reactivity.
• Low intrinsic viscosity resulting in increased application solids of the paint.
• Low volatility and therefore minimal weight loss during the cure cycle.
The replacement of 30% hydroxy acrylic by the caprolactone based polyols in one system gave an increase in volume solids content at spray viscosity of 5%, better impact resistance and greatly improved gloss after 1000 hours exposure to the QUV Weatherometer.
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