Coupling agent application

Monte, S.J. and Sugarman, G. (1985) Titanate and zirconate coupling agent applications in polymer composites. Developments in Polymer Technology - 2 (eds A. Whelan and J.L. Craft), Elsevier Applied Science Publishers, Barking, UK. 

The composition of an epoxide moulding material will greatly depend on the specific application, and this has been discussed at length. ". The resin may be of the epoxide novolac type and there will also be present hardeners, fillers (such as silica), a silane coupling agent, pigment, flame retardant and a wax release agent. 

In primer formulations for adhesive bonding of metals, the coupling agents that are most frequently used are those based on epoxy and amine functionalities. Aqueous solutions of aminosilanes have been successfully used for obtaining stable adhesive bonds between epoxy and steel [10] and epoxy and titanium [11,12], while epoxy functional silanes are preferable for applications involving aluminum substrates [13,14], A simple solution of % epoxy functional silane in water is currently used for field repairs of military aircraft [15] where phosphoric acid anodization would be extremely difficult to carry out, and performance is deemed quite acceptable. 

Fillers were initially introduced to reduce costs they have significantly lower cost than low cost commodity polymers. However, fillers are now added to polymers to enhance performance in many applications. Many of these benefits have emerged because of the greater adhesion between the polymer-filler interface. This arises from the use of coupling agents, which provide a bond, both physical and chemical, between the filler and the polymer matrix. 

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