Adhesion zirconates

Two examples of titanate coupling agents are shown below. The first contains amine groups and would be suitable for use with epoxide adhesives. Zirconate coupling agents have very similar structures to the titanates. 

Neoalkoxy zirconates also provide novel opportunities for the adhesion of fluorinated polymers to metal substrates because the introduction of a zirconate at the interface results in a metal oxygen zirconium VI organo fluoride. 

Organic titanates and zirconates have been found to provide several important functions as additives for organic adhesives and sealants. At least eight primary functions have been proposed.18 Organic titanates and zirconates can be used as... 

Adhesion promoters are the substances that improve adhesive strength of paints in terms of its resistance against mechanical separation from the painted surface. A large number of different chemical adhesion promoters are available. These include silanes, silicones, titanium compounds, zirconates, amides, imines, phosphates, and specially modified polymers. Furthermore, there are binders, plasticizers, and additives, which have the secondary effect of providing good adhesive strength. Adhesion promoters can be used as additives to the paint formulation, or can be employed in the form of a surface pretreatment. 

NZ Series. [Keniich Petrochemicals] Zirconates coupling agents adhesion promoters, antioxidants, antistats, accelerators, activatixs, catalysts, curatives, corrosion inhibitors, dispersants, emulsifiers, flame retardants, foamers, impact modifiers, release agents, retarders, stalnlizeis, etc. 

Solvent soluble compounds include zirconium acetylacetonate, zirconium methacrylate, and the family of neoalkoxyl zirconates. Some commercially available zirconates are shown in Table 3. Wang [8] has described the synthesis of a soluble linear Schilf base zirconium-based coordination polymer (N, N, N", A "-tetrasalicylidene-3,3 -diaminoben-zidene) zirconium, and other hybrid copolymers, and has demonstrated improved adhesion on glass and aluminum substrates for poly(methyl methacrylate), polyethylene, and polypropylene when used as hot-melt compounds. 

One of the reasons why the dispersion of inorganics in plastics and adhesion of a plastic to an inorganic substrate is so difficult is that many thermoplastics and rubbers, such as olefin-based polymers, are nonpolar. Titanates and zirconates are well-established adhesion promoters, as discussed in Ref. [1]. A recent example of bonding olefins to metals appears in Ref. [24]. Another example of the adhesion of polyolefins to foil electrodes using KR TTS has been provided by Kataoka [25]. 

Organotitanates, aluminates, zirconates and zircoaluminates can also act like silanes as adhesion promoters. They perform similar functions, but unlike silanes there is no need for water molecules to be eliminated. These other treatments bond the polymer to the filler surface by a chemical bond involving proton co-ordination, and they can also be used with fillers that are not receptive to silanes, such as calcium carbonate, carbon black and barium sulfate, as well as barium ferrite, magnesium hydroxide, aluminium trihydroxide, titanium dioxide, talc and the nanoclays. 

Zirconate coupling agents have a stracture very similar to that of titanates. Zirconium propionate is used as an adhesion promoter in printing ink formulations for polyolefins. Like the titanates, zirconate coupling agents are useful in improving the dispersion characteristics of fillers in polymer systems. 

Materials/characterislics Organosilanes. adhesion promoters, functionalized organic polymers, organotitanates. zirconates... 

Keywords fibre, surface, organosilane, titanate, zirconate, chrome complex, surface energy, contact angle, interface, mechanical properties, adhesion, maleic anhydride. 

Although used primarily as adhesion promoters, certain organometallic esters (titanates, zirconates, aluminates, zircoalmninates) and in some cases even silanes are used at catal)rtic levels in filled or reinforced epoxy resins to modify viscosity and achieve novel compositions. 

Zireonate eoupling agents provide an alternative, eorreeting the disadvantages of silanes and titanates. They do not produce color in contact with phenols other than nitrophenols. They do not interact with HAS and they often improve UV stability. Neoalkoxy zirconates provide novel opportunities for adhesion of polymers to metal substrates. They still have high cost. 

The enhancement of adhesion provided by asymmetric organotitanates and zirconates in reinforced composites appears to be a consequence of the interaction of multiple mechanisms, including ligand-specific interfacial wetting enhancement, primary chemical bond formation between the substrate particulate and resin matrix, and, in many instances, matrix repolymerization and reinforcement surface modification. The particular mechanism which is dominant in a specific application appears to... 

Kenrich is the outstanding company that has conducted research on titanate and zirconate coupling agents and produced these materials for adhesives and composites. This effort has led to many patents related to their products. U.S. Patent, 4,600,789 (July 15, 1986) and... 

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