In this book international experts discuss the state-of-the-art in the biological degradation of hydrocarbons to meet remedial or disposal goals. The work focuses on practical applications, often on globally important scales including the remediation of some of the world’s largest crude oil spills. Other related chapters discuss important implications of microbial transformation of hydrocarbons, including treatment of high fat processing wastes, impacts of microbial biodegradation activity on industrial processes, and the implications of microbial oil degradation in relation to modern oil extraction processes like hydraulic fracturing of shales and extraction of oil sands.

Providing guidelines for implementing sustainable practices for traditional petroleum based plastics, biobased plastics, and recycled plastics, Sustainable Plastics and the Environment explains what sustainable plastics are, why sustainable plastics are needed, which sustainable plastics to use, and how manufacturing companies can integrate them into their manufacturing operations. A vital resource for practitioners, scientists, researchers, and students, the text includes impacts of plastics including Life Cycle Assessments (LCA) and sustainability strategies related to biobased plastics and petroleum based plastics as well as end-of-life options for petroleum and biobased plastics.

Proceedings of the Third International Conference on Frontiers of Polymers and Advanced Materials held in Kuala Lumpur, Malaysia, January 16-20, 1995

Few scientific developments in recent years have captured the popular imagination like the subject of'biodegradable' plastics. The reasons for this are complex and lie deep in the human subconscious. Discarded plastics are an intrusion on the sea shore and in the countryside. The fact that nature's litter abounds in the sea and on land is acceptable because it is biodegradable - even though it may take many years to be bioassimilated into the ecosystem. Plastics litter is not seen to be biodegradable and is aesthetically unacceptable because it does not blend into the natural environment. To the environmentally aware but often scientifically naive, biodegradation is seen to be the ecologically acceptable solution to the problem of plastic packaging waste and litter and some packaging manufacturers have exploited the 'green' consumer with exaggerated claims to 'environmentally friendly' biodegradable packaging materials. The principles underlying environmental degradation are not understood even by some manufacturers of 'biodegradable' materials and the claims made for them have been categorized as 'deceptive' by USA legislative authorities. This has set back the acceptance of plastics with controlled biodegradability as part of the overall waste and litter control strategy. At the opposite end of the commercial spectrum, the polymer manufactur ing industries, through their trade associations, have been at pains to discount the role of degradable materials in waste and litter management. This negative campaign has concentrated on the supposed incompatibility of degradable plastics with aspects of waste management strategy, notably materials recycling.

The consumption of plastic products has increased significantly with the rapid development of the global economy. The total output of virgin plastics has already reached eight billion tons, and the annual global plastic consumption has reached 2.8 billion tons. In parallel with this high consumption rate, a staggering amount of plastic waste is generated annually. As a consequence of incorrect disposal of waste plastics and plastic longevity, this plastic waste is accumulating in the environment at an increasing rate. Moreover, since most plastic waste is corrosion resistant, these plastics do not decompose in the natural environment and can cause serious environmental pollution. In particular, petroleum-based synthetic polymers, including polyethylene, polyvinyl chloride, polystyrene, polypropylene, polyethylene terephthalate, and polyurethanes need hundreds of years to completely degrade in the natural environment. Moreover, although some aliphatic polyesters, such as polybutylene succinate, polycaprolactone, and polylactic acid are considered biodegradable, degradation of these plastics occurs only under specific microorganism activity and under specific conditions. Sometimes the apparent degradation is initiated by hydrolytic activity and not microorganism or enzymatic activity. Large-scale synthesis and application of plastics only began after 1950. Hence, the time span of plastic exposure in the environment has been too short for the adaptive evolution of natural microorganisms. Indeed, natural microorganisms showing high specificity for plastics and a high degradation efficiency are extremely scarce. Because of the inability of most natural microorganisms to recognize and degrade plastics, enzymes that can specifically degrade plastics are also scarce. Many of the enzymes which are known have either an unclear mechanism of the action on the polymer, a poor affinity for their substrates, a low efficiency, or enzyme production yield is currently low. To address these problems, new biotechnology strategies need to be implemented. In particular, new microorganisms and their enzymes need to be identified, and pathways for plastic degradation and molecular modification need to be clarified to enhance the activity and stability of the degrading enzymes. The current Research Topic aims to cover the recent and novel research trends in the development of plastics biodegradation (including petroleum-based plastics and bio-based plastics) under soil, composted, microbial and enzymatic conditions. The recycling technology of degraded products is also of interest.

Beginning with a general overview of nanocomposites, Bionanocomposites: Integrating Biological Processes for Bio-inspired Nanotechnologies details the systems available in nature (nucleic acids, proteins, carbohydrates, lipids) that can be integrated within suitable inorganic matrices for specific applications. Describing the relationship between architecture, hierarchy and function, this book aims at pointing out how bio-systems can be key components of nanocomposites. The text then reviews the design principles, structures, functions and applications of bionanocomposites. It also includes a section presenting related technical methods to help readers identify and understand the most widely used analytical tools such as mass spectrometry, calorimetry, and impedance spectroscopy, among others.