Composite Chevron sulfur

Table I. Properties of a Typical Chevron Sulfur Composite...

The properties of a typical Chevron sulfur composite are shown in Table I. One desirable feature is the low melt viscosity in the 250°-300°F range. This provides considerable latitude in the choice of application methods. Spray has proven to be effective for many uses. Brush, roller, and dipping have also been used for some coating applications. Most composites can be put into service immediately after application because they attain most of their strength and durability shortly after they solidify from the melt. 

Figure 2. Chemical resistance of typical Chevron sulfur composites to water, sea water, NagSOk (saturated), HgSOk (2N), and HCl (2N).

Sulfur s coefficient of thermal expansion can be reduced significantly when modified with plasticizers and fillers. Most Chevron composites have coefficients of expansion about one-half that of elemental sulfur. Even lower coefficients are possible with very high levels of filler. These lower coefficients contribute to the improved thermal shock resistance of sulfur composites and to their reduced tendency to crack or craze. 

Canal Lining. Sulfur composite was used to line an earthen irrigation canal in southern Alberta, Canada (7,8) (Figures 4 and 5). This installation was a joint project between Chevron, The Sulphur Development Institute of Canada, and the Eastern Irrigation District. 

Chevron has demonstrated that it is commercially feasible to use sulfur composites as protective coatings and construction materials. This was done with large-scale field installations using special equipment and application procedures. Future efforts will focus on the commercial development of Chevron Sucoat products for these and other practical uses. 

Chevron s emphasis has been directed mainly toward high-strength, sprayable composites which are chemically modified sulfur that contains organosulfur plasticizers, fillers, and other additives. The type and amount of each additive is selected to impart the properties required for each end use. 

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