7 - Soaps, synthetic surfactants, and polymers

Abstract

This chapter reviews the chemical nature, synthesis, and environmental problems associated with biodegradable and nonbiodegradable organic compounds. Most of the polymers and surfactants in the detergents are made mainly from the chemicals derived from petroleum, and contain segments of linear or lightly branched hydrocarbon chains. Both soaps and synthetic detergents have similar structures, and their mechanisms of cleansing are also similar; however, zeolites of the detergents have environmental problems and they promote surface algal blooms. Microorganisms in the environment can utilize the energy of oxidation released by some hydrocarbons, soaps, and surfactants through β-oxidation. The chapter illustrates the microbial metabolism of hydrocarbons, soaps and synthetic detergents, and proposes guidelines to facilitate the understanding of microbial degradation of detergents. Although progress has been made in the synthesis of biodegradable polymers, these materials cost more, and in general, their properties are not as useful as those prepared from petroleum feedstock. A potential problem associated with biodegradable surfactants is the eutrophication of lakes that results from microbial degradation. The biodegradable replacements have solved the environmental problems associated with nonbiodegradable surfactants, and it is likely that biodegradable polymers assume an increasingly larger percentage of the polymer market.