Polymers life cycle analysis

It is environmentally important to perform a life cycle assessment analysis, not only for non-biodegradable polymers but also for partially biodegradable or even completely biodegradable polymers. Life cycle analysis (LCA) is a tool which helps in understanding the environmental impact associated with the products, processes and activities throughout the life of a polymer. The life cycle of vegetable oil-based polymers is shown in Rg. 2.6. Thus a complete LCA would include three separate but interrelated components, an inventory analysis, an impact analysis and an improvement analysis. 

In the past decades, polymer materials have been continuously replacing more traditional materials such as paper, metal, glass, stone, wood, natural fibres and natural rubber in the fields of clothing industry, E E components, automotive materials, aeronautics, leisure, food packaging, sports goods, etc. Without the existence of suitable polymer materials progress in many of these areas would have been limited. Polymer materials are appreciated for their chemical, physical and economical qualities including low production cost, safety aspects and low environmental impact (cf. life-cycle analysis). 

In polymer applications derivatives of oils and fats, such as epoxides, polyols and dimerizations products based on unsaturated fatty acids, are used as plastic additives or components for composites or polymers like polyamides and polyurethanes. In the lubricant sector oleochemically-based fatty acid esters have proved to be powerful alternatives to conventional mineral oil products. For home and personal care applications a wide range of products, such as surfactants, emulsifiers, emollients and waxes, based on vegetable oil derivatives has provided extraordinary performance benefits to the end-customer. Selected products, such as the anionic surfactant fatty alcohol sulfate have been investigated thoroughly with regard to their environmental impact compared with petrochemical based products by life-cycle analysis. Other product examples include carbohydrate-based surfactants as well as oleochemical based emulsifiers, waxes and emollients. 

In terms of the product life cycle analysis, a new product or polymer would generally require about thirty years from the research and development stage before becoming a commodity product when millions of tonnes are produced annually for mainstream application. In 2005, the biodegradable plastics industry has about fifteen to twenty years of development time behind it and has now reached the market introduction stage. 

Shen, L., Haufe, J. and Patel, M. (2009) Product Overview and Market Projection cf Emerging Bio-Based Plastics, downloadable from http //www.epnoe.eu/research/Life-Cycle-Analysis (accessed 8 luly 2013). Lemstra, P. (2008) Introduction - Synthetic versus natural polymers. European polymer Federation workshop on Bioplastics Crossing the border between synthetic and natural polymers - May 30-31, Paris. Kim, S. (2004) Global potential bioethanol production from wasted crops and crop residues. Biomass and Bioenergy, April, 361-375. 

Plastics rely on a feedstock used for energy production, but at the same time they need less of it per ton of product than other materials. The European Association of Plastic Manufacturers (APME) in Brussel has made a big effort over the last decade to develop a life-cycle analysis approach for an environmental positioning of all major plastic materials [1]. Meanwhile, the data for most polymers for resource demand and major emissions have been evaluated and published based on the average data of all European production sites. 

Volume 1 of this book is comprised of 25 chapters, and discusses the different types of natural rubber based blends and IPNs. The first seven chapters discuss the general aspects of natural rubber blends like their miscibility, manufacturing methods, production and morphology development. The next ten chapters describe exclusively the properties of natural rubber blends with different polymers like thermoplastic, acrylic plastic, block or graft copolymers, etc. Chapter 18 deals entirely with clay reinforcement in natural rubber blends. Chapters 19 to 23 explain the major techniques used for characterizing various natural rubber based blends. The final two chapters give a brief explanation of life cycle analysis and the application of natural rubber based blends and IPNs. 

PP has lower specific gravity than other plastic materials. Having broad resistance to organic chemical ingredients, they are used in consumer products. The total environmental impact of PP and other thermoplastic materials is less than traditional materials in life-cycle analysis. Commercial PP is a complex mixture of varying amounts of isotactic, syndiotac-tic, and atatic polymers with a given MWD. 

Journal of Biobased Materials and Bioenergy. 2007- Valencia, CA American Sdentilic Publishers (1556-6560). Online at http //www.aspbs.com/jbmbe/ (1556-6579). Publishes research on biobased polymers and blends, biobased composites and nanocomposites, biobased materials processing technologies, life-cycle analysis, social and environmental impacts, and biofuels. 

In the foregoing we have presented a general framework for sustainable polymer reaction engineering. Its most important characteristic lies in the concerted multidisciplinary approach, rather than focusing on individual competencies. Given the volume of polymer production, it will be of major importance that environmental and safety issues become an integral part of the development process. In combination with tools such as life cycle analysis and product-inspired PRE, this will allow the development of sustainable new polymer processes. 

Figure 2. Life cycle analysis results for energy content of various thermoplastic polymers. PLAl represents present technology PLA Bio/WP is the projection for the production of PLA from agricultural waste using wind power.

A detailed examination of the advantages and disadvantages of polymer recycling by considering several life cycle analysis case studies is given in [82]. Here, a short description of the relevant life cycle analysis of flexible polyurethane foam wastes is presented, with emphasis on the relation between the start and the end of the product s life, i.e., including process and product design. 

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