5 сентября, 2015 
Malyar Most acrylic adhesives are supplied as two high viscosity liquids or pastes that are mixed together, called ‘‘Mix-in Accelerator” systems. Some types can also optionally be cured by no-mix accelerator lacquers. Accelerators are low viscosity liquids which are brush or spray applied to one or both of the substrates being bonded. Following accelerator application, the unmixed adhesive is applied to the primed substrate. This method eliminates the need for premixing the adhesive and accelerator, which eliminates pot life concerns.
Many acrylic adhesive products also go through a notable color change as they cure, which is unique to these materials. This color change can be used as a rough indicator of cure state and can be utilized in many manufacturing situations as an effective means of verifying the presence of both adhesive components.
Because many acrylic adhesives cure very rapidly with a significant exotherm, manufacturers generally recommend that quantities greater than a pint (ca. 0.47L) should not be mixed at one time. As a consequence of the rapid exothermic cure of many acrylic adhesives, the use of dual component cartridges is often ideal. Most products can be purchased in ready-to-use cartridges. For large continuous operations, various automated types of meter-mix-and-dispense equipment are marketed by a number of engineering companies.
One typical concern with acrylic adhesives, specifically those containing methyl methacrylate as a component, is the characteristic odor of the methyl methacrylate monomer. This odor may be objectionable to some people and may result in the use of other types of adhesives instead. Later in this chapter some of the new ‘‘low odor’’ formulations will be briefly discussed as alternative adhesives where odor has been an issue. This new technology offers performance characteristics equal to methyl methacrylate-containing products, albeit at a higher price.
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