Additives

Additives are a common name for agents which are added to the matrix. Depending upon their purpose, additives can be divided into three fundamental groups: price-reducing additives, process-related additives and function-related additives. While the purpose can vary, additives will always influence the corrosion resistance of profiles, as well as their mechanical and fire-technical properties.

Price-reducing additives*

The only function of price-reducing additives is to fill out the form of a profile, and adding such additives enables reduction of more expensive reinforcement and matrix materials. It is thus possible to reduce the price of the finished profiles accordingly. Profiles have significantly poorer mechanical properties when the amount of reinforcement is reduced. Moreover, most types of price-reducing additives also result in lower corrosion resistance and lower resistance to most chemicals.

None of the Fiberline structural profiles described in this book contain price-reducing additives.

*Are often referred to as fillers.

Process-related additives

Process-related additives are substances with advantageous effects on the pultrusion process, and on the properties and appearance of a cured profile. An example of this is a so-called low-profile additive which is used to avoid excessive shrinkage during curing of profiles. The additive prevents formation of hair-line cracks in surfaces, while improving profile resistance to corrosion, as well as improving fatigue properties. It also gives profiles more exact geometric tolerances and lower internal stress.

Function-related additives

Function-related additives have an advantageous effect in relation to the use of a finished profile. An example of this is the adding of pigments. Fire retardants are another example. The latter are added to obtain self-extinguishing properties and to retard flame spread.

Of course, function-related additives can also be added in amounts so large that they degrade the mechanical properties of a profile.

All the profiles which are presented in the Design Manual have been tested with the relevant content of process- and function-related additives.

See also the Fiberline Quality Codex.