Fillers Extenders: An Overview
Fillers and extenders are non-adhesive materials. They are used in adhesive and sealant formulations to improve properties and to lower cost.
There is a wide variety of fillers and extenders in adhesives and sealants. They can be both organic and inorganic. Besides, in a filler family, grades vary in size (mean and distribution), aspect ratio, surface area, and surface chemistry.
Their loading can vary from just a few percent to where the filler is the major component by weight. It depends on the primary resin, the other ingredients in the formulation, and the targeted end-properties.
Fillers can have a deep effect on cost, compounding characteristics, and final adhesive properties. So you should select them with care.
This guide will direct you through the selection process of fillers & extenders. You will be able to identify the best filler or extender for a specific base polymer / end-use requirements pair.
Fillers are available in many forms including particles, fibers, and mats or fabrics. The table below lists common forms of fillers and reinforcements that are used with adhesives. It should be noted that adhesive film carriers such as fabrics or mats can be considered as a type of filler.
| Non-Fibrous Fillers
| Fibrous Fillers
- Continuous or chopped strands
- Spun and woven roving
- Fabric and mats