Organo-Titanates and Zirconates

Organo-titanates are a very interesting class of surface modifier, which have aroused great interest in recent years. They can all be regarded as derivatives of ortho-tkanic acid, Ti(OH)4, and hence are commonly known as organo-titanates rather than by their systematic names. This convention will be adopted here, in order to be consistent with existing literature. 

While several companies produce organo-titanates for a variety of uses, one group of workers (Monte and Sugerman) have specialised in producing compounds for filler modification, which they refer to as coupling agents. As well as producing an enormous 

As well as arousing interest, the organo-titanates have also aroused a great deal of controversy. This is mainly related to their mode of action, and in particular, whether they act as true coupling agents, or merely as very effective dispersants. 

Unfortunately while there is an extensive literature, most of this is of a commercial or purely effect describing nature and there have been virtually no useful basic scientific studies. This has combined with the bewildering range of available products to create confusion and some distrust of the products. 

The natural chemistry of titanium causes problems with organo-titanates in some applications. To overcome this, organo-zirconate products have been recently introduced. The structure and general principles of the zirconates are similar to the titanates and no separate discussion of them will be made, except to point out reasons why zirconates are preferred in some applications. 

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