Organotitanate Coupling Agents

The filler surface treatment can also be applied as an additive to the adhesive formulation. Coupling agents, such as organotitanates, zircoaluminates, or organosilanes, are added to the formulation so that they preferentially find their way to the filler s surface and provide for optimal surface chemistry and adhesion between the filler and the matrix resin. These coupling agents are discussed in Chap. 10. 

Coupling agents improved interface silanes by stress transfer, organotitanates wetting " < composites... 

Polytner Encapsulation of Inorganic Particles 99 Table 4.3 Some commercial silane and organotitanate coupling agents. 

The use of organotitanate and/or organozirconate coupling agents, either independently or optionally together with other surface-reactive materials, such as organosilanes, also significantly improves the properties and processability of fibre-reinforced polymers, and their resistance to chemical attack and corrosion. 

Figure 4 Structures of some non-silane coupling agents (a) a chrome complex (b) an organotitanate. From [1] and [3].

Efficient coupling agents are silanes [1,55,62,69-71] and organotitanates [72-74], which are easily dispersed and present a high chemical resistance. Chromium coordination complexes and substances containing phosphorus are also used. 

A series of organotitanate coupling agents is commercially available from Kenrich Petrochemicals, Inc., U.S., under the general trade name Ken-React. Table 4.5 gives a list of these coupling agents with their abbreviations [58]. 

Mascia [3] mentions the following types of coupling agents or adhesion promoters, besides organotitanates ... 

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