Biodegradable Polymers from Petrochemical Products

Bionanocomposites Using Biodegradable Polymers from Petrochemical Products... 

While PHB and PHV are not considered true plastics, another biodegradable polymer polycaprolactone (PCL) is a plastic material because its monomer e-caprolactone is obtained on an industrial scale from petrochemical products (cyclohexanone and peroxyacetic acid). This synthetic plastic with its low melting point is easily extrudable and applications in the packaging area are envisioned. 

For the time being, it is not possible to make a general judgement about whether biodegradable plastics should be preferred to petrochemical polymers from an environmental point of view. As a prerequisite for drawing such a conclusion, full-sized LCA studies would be needed for PHA, PLA and other important biodegradable polymers including those manufactured from fossil feedstocks, e.g., BASF s product Ecoflex and Eastman s Eastar . But even if those were available one would be left with considerable uncertainties, e.g., because it will never be feasible to cover all possible products and all... 

Most of the plastics and synthetic polymers that are used worldwide are produced from petrochemicals. Replacing petroleum-based feedstocks with materials derived from renewable resources is an attractive prospect for manufacturers of polymers and plastics, since the production of such polymers does not depend on the limited supply of fossil fuels [16]. Furthermore, synthetic materials are very persistent in the environment long after their intended use, and as a result their total volume in landfills is giving rise to serious waste management problems. In 1992,20% of the volume and 8% of the weight of landfills in the US were plastic materials, while the annual disposal of plastics both in the US and EC has risen to over 10 million tons [17]. Because of the biodegradability of PHAs, they would be mostly composted and as such would be very valuable in reducing the amount of plastic waste. 

Lactic acid is commonly found, which contributes to its wide use in food and food-related industries. It also has the potential for production of biodegradable and biocompatible polymers. These products have been proven to be environmentally friendly alternatives to biodegradable plastics derived from petrochemical materials (Zhang, Jin, and Kelly, 2007). Lactic acid is slightly lipid soluble and diffuses slowly through the cell membrane. As a result of this, the disruption of the cell pH is not its main mode of inhibition (Gravesen et al., 2004). 

Abstract The development and production of biodegradable starch-based materials has attracted more and more attention in recent years due to the depletion in the world s oil resources and the growing interest in easing the environmental burden from petrochemically derived polymers. Furthermore, the unique microstructures of different starches can be used as an outstanding model system to illustrate the conceptual approach to understanding the relationship between the structures and properties in polymers. 

PHAs have frequently been championed as a solution to sustainable polymer production. This is because they can be produced from renewable raw materials and are biodegradable upon disposal. However, an inventory of materials and energy required to produce these polymers reveals a rather discouraging picture. In most categories quantifying environmental impact (land use, resource depletion and emissions to air and water) PHA production by fermentation scores worse than conventional petrochemical polymer production. 

Prior to the 1930s all adhesives were based on natural products (eg, proteins such as animal blood, casein, soy protein). Use of adhesives from natural products steadily decreased thereafter with the development of synthetic polymers that had superior properties. Recently, renewed interest has been shown in using natural products to replace, entirely or in part, petroleum-based adhesive components with natural products, without sacrificing the performance levels achieved with modem petroleum-based adhesives. The purposes are often to reduce cost and dependence on petrochemicals, to reduce formaldehyde emissions, and improve selected properties (eg, biodegradability). 

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