Epoxy-Polysulphides

Adducts can be manufactured from either liquid or solid epoxy resins by using whatever level of LP is appropriate for the properties required for the cured product. The only limitation is that a molar excess of epoxy resin must always be maintained (Rees et al, 1994 Morton International, undated a). Properties of epoxy-polysulphide adducts manufactured by the above route include (Morton International, undated a) ... 

Epoxy-polysulphide adducts or prepolymers are commercially available under the trade name ELP (a trade mark of Morton International). Properties of one such adduct, ELP-3 are presented in Table 10.1. 

Table 10.1 Properties of commercial epoxy-polysulphide polymer ELP-3 (Morton International). Source Morton International Ltd, Coventry, UK...

Figure 103 The weathering resistance of epoxy-polysulphide coatings after one month of outdoor exposure [A] LP-epoxy modified coating [B] unmodified epoxy coating. Substrate = oily, rusty and wet mild steel. Reproduced with permission from Morton International...

Another example of epoxy-polysulphide coating application is for the Indian Molasses Co. Ltd tank farm facilities in Mangalore where the nature of the atmosphere is highly corrosive. Several tanks have been coated (Figure 10.8) (Morton International, undated d). 

Epoxy-polysulphide coatings exhibit excellent adhesion to steel, aluminium and concrete without the use of primers (Morton International,... 

Adhesives. Epoxy-polysulphide adhesives are elastomeric in nature. Therefore, they can withstand movement and vibration. They reduce stress between dissimilar bonded materials. They are used as... 

Figure lO Epoxy-polysulphide coating at Indian Molasses Co. Ltd, Mongalore. The tank on the front left-hand side has two coats. The next tank on the right has its seccnd coat almost completed. The third tank has reedved one coat. The tank on the far right-hand side is being prepared to receive its first coat. Reproduced with permission from Morton International Ltd, Coventry, UK... 

Fig. 3.1. Effect of water on the fracture energies of bonded joints, as a function of time, (a) Aromatic amine cured epoxy, b) Aliphatic amine cured epoxy, (c) Epoxy polysulphide.

Tertiary amines also catalyse interaction between the hydroxyl groups formed and remaining epoxy groups and a cross-linked structure is built up. Epoxy-polysulphide compositions have good impact strength and find use in adhesives and castings. 

Epoxy-polysulphide Polyvinyl acetate > Wood adhesives — 0 101 0 35 Krueger (1962)... 

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