13 августа, 2015 
Malyar The molecular weights of thermosetting acrylics are considerably lower than their thermoplastic counterparts, since the final crosslinked film is built up during the curing reaction. As a consequence of this difference in molecular weight, the thermosetting types are generally soluble in a wider selection of solvents, e. g. aromatic hydrocarbons, alcohols, esters, ketones and glycol ethers. These solvents are selected on the basis of cost and evaporation rates to suit the different types of application methods used.
The drive towards lower VOC (Volatile Organic Compound) content is in part achieved through lower molecular weight polymers with a narrow molecular weight distribution, and also through solvent selection. A better solids/viscosity balance is achieved through the use of stronger solvents. This entails replacement, or partial replacement, of aromatic hydrocarbons with ketones, such as methyl isobutyl ketone (MIBK), methyl amyl ketone (MAK), methyl isoamyl ketone (MIAK), and esters, such as butyl acetate. Environmental pressure has also restricted the use of aromatic solvents in some parts of the world.
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