Toughened acrylics surface preparation

Many formulations are claimed to be capable of absorbing normal residues of rolling oil on steel surfaces, thus reducing the surface preparation requirements as compared with, say, epoxies. As with epoxies, acrylics can be toughened by the introduction of a rubbery phase within the matrix of the adhesive and they are particularly suitable for polymeric adherends because the surface is eompliant. 

In the mid-seventies, spurred by developments from the DuPont Corporation, a new kind of two-component acrylic adhesive system was introduced to the joining industry. The DuPont technology has been widely licensed and is now referred to by numerous terms such as "second-generation acrylics", "reactive adhesives", "modified acrylics", "toughened acrylics", etc. These adhesives seemed to answer the need for improvements over some of the major disadvantages found in anaerobic structural adhesives, namely those of cost, the need for scrupulous surface preparation, and the ability to bond plastic surfaces. 

Quite contrary to popular belief - a belief founded on the use of traditional adhesives - reliable joints can be obtained from unprepared surfaces. Of course, there is no denying that the better the preparation the better the overall performance. But, providing contamination is not gross, perfectly adequate levels of performance can normally be obtained from Anaerobic Cyanoacrylate Plastisol Toughened acrylic and Toughened, heat-cured, epoxide-based adhesives. 

Extremely versatile, these adhesives will readily bond almost any substrate with the exception of some rubber-based materials and the difficult thermoplastics such as polyethylene. Even the latter may respond well if the surface is correctly prepared before bonding. The toughened acrylics are very robust and will cope with demanding environments. 

Steel (stainless) 2-3 Load-bearing when used with toughened acrylics and heat cured epoxides careful surface preparation may not be necessary... 

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