Additives biocidal compounds

Although the musk fragrances and biocides often are released to the aquatic environment, many of them may be transported to other media, including the atmosphere. As discussed above, the processes in the atmosphere are all chemical degradation processes and the ability for a chemical to reach the atmosphere will depend on the Henry s law constant (Hc). In addition, some of these products may be susceptible to chemical hydrolysis. Table 16.5 lists the musk fragrances and biocide compounds along with the Henry s law constant estimated by EPISuite... 

In addition to their antiknock properties, organic lead compounds possess bactericidal properties and motor fuels with lead are known to inhibit bacterial growth during storage in contact with water. With the disappearance of lead-based compounds, it is necessary to incorporate biocides from the cyclic imine family, (piperidine, pyrrolidine, hexamethyleneimine), alkylpropylene diamines or imidazolines (Figure 9.2). 

Polyvinyl chloride is processed into a number of forms by including additives. Additives are used to vary the properties of PVC so that it can be made soft and flexible or hard and rigid. Additives are also used to inhibit decomposition as a result of exposure to sunlight, ozone, and chemicals. Plasticizers are the primary additive included in PVC materials. Di(2-ethylhexyl) phthalate (DEHP) and a host of other phthalates are the most common plasticizers. Plasticizers impart flexibility, thermal stability, strength, and resilience to PVC compounds. PVCs without plasticizers are classified as UPVC the letters stand for unplasticized polyvinyl chloride. UPVC is rigid and used for conduit, containers, gutters, and floor tiles. Other common PVC additives are biocides, lubricants, and pigments. 

Biocides - [AMNES-CYCLOALIPHATIC AMINES] (Vol 2) - [INDUSTRIALANTIMICROBIALAGENTS] (Vol 14) - [THERMAL POLLUTION] (Vol 23) -m adhesives [VINYL POLYMERS - VINYLACETATE POLYMERS] (Vol 24) -dicyandiarmdes m [CYANAMIDES] (Vol 7) -m grouts [SOIL STABILIZATION] (Vol 22) -mtro alcohols as [NITRO ALCOHOLS] (Vol 17) -m papermaking [PAPERMAKING ADDITIVES] (Vol 18) -m papermaking [PAPERMAKING ADDITIVES] (Vol 18) -PVC as [VINYL POLYMERS - VINYL CHLORIDE POLYMERS] (Vol 24) -quaternary ammonium compounds as [QUATERNARY AMMONIUM COMPOUNDS] (Vol 20)... 

Biocides. The attack of fungi on the several components of a vinyl formulation may manifest itself as an unsightly growth looking much like dirt or may result in the formation of discolored areas (yellow, pink, blue, clear) on the finished goods. Outdoor exposure, indoor exposure in humid atmosphere, soil burial or contact, and electrical insulation compounds are typical areas where biocide addition is indicated. Since most commercial biocides are heavy metal derivatives, care must be taken to assess their effect on heat and light stability and compatibility with the vinyl system in which they are used. 

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