Polyesters metal containing

Preformed Two-Piece Metal Containers. Ink vehicles for letterset printing of two-piece aluminum or steel containers are mainly based on special polyester vehicles used in conjunction with melamine cross-linkers. Short cycle ovens which dry inks in 1—5 seconds are now used and operate at temperatures as high as 350 °C. The rheology of these inks must be adjusted to the unique geometry of the press. Desired rheological properties are achieved by the use of additives as weU as extender pigments. 

There are two basic VPI resin formulations. One is based on epoxy resins, and the other is based on unsaturated polyesters. Both are typically one-part solventless compositions that are completely polymerizable. Volatile, nonpolymerizable solvents cannot be tolerated because these will lead to bubbling in the vacuum impregnation procedure. To control viscosity of the resin formulations, the epoxies contain low-viscosity, reactive diluents of the monoglycidyl ether type the unsaturated polyester formulations contain styrene or vinyltoluene as reactive diluents. Both resin types contain catalysts that become active only at elevated temperatures to insure long-term stability at room temperature. The epoxy resins are frequently catalyzed with metal organic compounds such as titanium complexes, and peroxides are usually the main catalyst in the unsaturated polyester formulations. In addition to the ingredients mentioned here, the compositions may contain additives such as cocatalysts, activators, and accelerators. However, there are no particular fillers used in VPI resins. 

Uses Polyester for container applies., metal deco finishes, OEM primer finishes, inks, coil coatings, general industrial finishes adhesion modifier for coil coatings... 

Although the convenience of plastic bags is perhaps outweighed by their blight on the environment, think of what we would not have if we had none of the polymeric materials invented by chemists and then fabricated in bulk. Think of a world without nylon and the polyesters of fabrics for clothing, upholstery, and decoration. Think of a world with only heavy metal containers for drinks, food, and household fluids. Think... 

In some cases it is possible to directly polycondense acid and phenols evolving water at about 300 C [41]. This process works well when catalysed with compoimds of group IV or V metals tin salts are preferred, especially dialkyl tin dialkanoates or oxides. The process is not really suitable if p-hydroxybenzoic acid is involved because this can imdergo decarboxylation at >200 "C. The polymerisation is not affected because the phenol formed volatilises at the high temperatures involved, but the resultant polyester will contain less than the anticipated mole ratio of hydroxybenzoate-derived units. Hydroxynaphthoic acid does not suffer from this problem, and direct esterification processes may be used if non-benzoate copolymers are required [42]. 

It is quite apparent from the state-of-art of the subject that a variety of dimer acid-based polymeric systems has been investigated from the viewpoint of commercial applications. However, their plasticizing polyester still are known on a limited scaie also, no research in the area of metal containing dimer acid polyesters has been done. The kinetics of the polyesterification of dimer acid with different polyhydroxy compounds was studied by Bajpai and Nivedita [90-94]. 

For metal-containing polyesters of dimer acid, synthesis was carried out using various divalent metal ions. Metal-containing polyesters include diverse systems such as ionomers, polymer-bound coordinating ligands, organometallic polymers with metal as a part of polymer backbone, metal polymer composites, and metal-... 

In the first step of synthesis for metal-containing polyesters of dimer acid, metal-containing diols were prepared with various divalent metal ions Zn(II), Ni(II), Co(II), Cu(II), Mn(II) and Ca(II) by a known method [97,98], using butanediol in place of ethylene glycol. The product (i.e., metal salts of mono hydroxy butyl phthalates, M[HBP]j) separated as white or intense colored precipitate. The reaction scheme is given in Figure 1. 

All the metal-containing polyesters of dimer acid and metal salts of mono hydroxy butyl phthalates M(HBP)j were colored solids, insoluble in water, and most were organic solvents. These polyesters having Zn(II), Mn(Il), Ca(II) do not melt until 320°C, whereas, polyester of Cu(HBP)j decomposes at 170°C. The product of dimer acid and Co(HBP)j was hygroscopic in nature and becomes sticky by absorbing moisture. 

The formation of polymers is confirmed by ir spectra analysis. The ir spectra of polyesters were compared with the ir spectra of dimer acid and that of its metal diols to ascertain the bonding in polyester. The comparison of ir spectra of butanediol-dimeracid poiyester and of metal-containing polyester leads us to conclude the latter have ionic linkages between metal ions M(I1), and carboxylate groups appeared as a strong absorption band in the range of 1,580-1,560 cm" and 1,598-1,590 cm". ... 

Further, the thermogravimetric analysis of metal diols of HBP and respective metal-containing polymers was done to study the thermal stability of the polyesters. The TG data show that all the polyesters are very stable up to 250°C. The energies of activation of degradation of these polyesters have been calculated using the Fuoss method [106]. 

Further incorporation of metal ions and aromatic structure in the main chain of these polyester enhances the thermal stability as well as resistance towards solvents. Owing to these properties, these metal-containing polyesters may be used for hard surface coatings where thermal resistance is required. 

As previously noted (Introduction) a number of metal-containing polyesters have been synthesized employing organometallic dihalides and salts of dicarboxylic acids. Further the synthesis of phosphorus-containing polyesters and polyamides has also been accomplished (for instance 11-15). Previous attempts by our group to synthesize the analogous phosphorus anhydrides failed. 

Metal-containing three-dimensional polyesters have also been prepared from calcium and magnesium hydroxyethyl phthalate, pyromellitic dianhydride, and epoxides. ... 

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