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Issue 06/2016

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Materials Green PU from

Materials Green PU from olive oil residues By: M. Bagni, D. Granados National University of San Juan, Argentina M. Reboredo National University of Mar del Plata, Argentina While the olive oil industry is a very important one, it is one that generates large amounts of waste, both solid and liquid. Using the olive oil fractions that are unfit for human consumption without refining to synthesize polymeric materials could offer a plausible solution when no refining plants are nearby. Olive Oil extraction process In the research project described here, the first step was to study the olive oil extraction process, during which the focus was on the output streams of the process. There are two output streams in the two phase-extraction process: the solid phase and the oily phase. The solid phase is known as olive wet husk, which may contain up to 5 % of residual oil. This residual oil is extracted with solvents and recovered as olive pomace oil (OO). It must first be refined before it is fit for consumption. The oily phase obtained from damaged olives or overripe olives is called lamp oil (AL) and also must be refined if it is intended for human consumption. Finally, the oily stream extracted from the bottom of the decanters, which is accompanied by sludge and vegetation water and is known as clear oil lees, should also not be consumed directly (CB). These three non-edible oils are potentially useful as raw materials for green polyols. They can be chemically modified to make them suitable for the polymerization process with diisocyanates, by incorporating reactive groups able to react with isocyanate groups (NCO). In this way, polyurethanes can be produced that can compete thermally and mechanically with those obtained from non-renewable sources. in the oils were increased at the expense of their points of unsaturation. As a result of the second stage, a mixture of different polyalcohols containing one or two hydroxylated fatty acid chains were achieved. This research aims to: • produce a biopolymer from vegetable oils, particularly a green polyurethane • offer an alternative use for the oily fractions of olive oil unfit for human consumption without refinement • be able to compete in thermo-mechanical issues with petroleum-based polyurethanes • broaden the knowledge of this subject, as there is no known background of obtaining polymers from these olive oil fractions. Future plans The synthesis stage has already started and although some promising results have been accomplished, there is still a long way to go, with huge challenges lying ahead. The aim is to obtain a composite material in which the matrix is formed by this green polyurethane and whose filling is the main solid waste from the olive oil industry: olive wet husk. The liquid residues were modified by performing two sequential treatments. First, the oils were epoxidized and hydrolyzed; next they were transesterified. During the first stage, OH groups were incorporated at the points of unsaturation. The viscosity and the content of OH groups Olives Phase Separation Classification, Cleaning and Washing Olive wet husk Solvent Extraction Olive Pomance Oil Grinding Dirty Oil Settling Thermo-mixing Sediment Oil Filtering and Packaging Clear Oil Lees 30 bioplastics MAGAZINE [06/16] Vol. 11

Materials Improve transparency and performance of PLA State-of-the-art impact modifier masterbatches for PLA address the ever increasing demands of performance and aesthetics of the market Sukano (Schindellegi, Switzerland), a world leader in the development and production of additive and colour masterbatches and compounds for polyester and specialty resins, introduces a new performance impact modifier portfolio range for PLA. Impact modifiers are an essential ingredient for nearly everyone processing PLA. The dilemma has always been successfully determining the threshold and balance of cost-in-use without sacrificing final product performance and aesthetics. Developing a tougher PLA In order for a masterbatch to impart toughness to PLA, several criteria must be met. One is assurance of the particle size curve in the formulations and its homogenous distribution in the matrix polymer. This must be highly compatible and thermally stable at PLA processing temperatures, ultimately resulting in a material with highly improved toughness. Processing conditions as suggested by Sukano specialists, ensure these are met in all its products. Generally, improved toughness is obtained by increasing amounts of masterbatch. With Sukano additive masterbatch impact modifier for opaque applications, excellent toughness can be obtained at 10-20 %. For transparent applications, quantity levels of 2-4 % are often enough. Overcoming challenges Adding impact modifiers can also have negative effects: for example, reduction in the modulus in proportion to the amount added, or chemical interactions and degradation. These are due to additive or polymer interactions, and can cause color issues or molecular weight losses. Another issue is obtaining adequate dispersion. The masterbatch needs to be highly compatible with PLA, otherwise, blending will not adequately disperse it into the PLA matrix during film extrusion, which could then lead to clustering during process operations, causing high die swell, surface imperfections and property variability along the film or thermoformed parts. Additionally, some impact modifiers do not meet the requirements of biotoxicity and blending them with PLA can affect compostability according to internationally accepted standards like EN 13432. With Sukano high performance impact modifier masterbatches, these challenges can be overcome. Sukano´s extensive 30 years of know-how in polyester resins enables the company to offer products that provide high levels of clarity without compromising short cycle times and part integrity needed by the film and thermoforming industry. Sukano´s impact modifier masterbatch increases the toughness and reduces the brittleness of PLA, expanding PLA’s value beyond packaging to a wider range of end applications, including durable goods or any final article where clarity and performance are essential. For example, the clear impact modifier masterbatch provides a substantial increase in toughness, resulting in better tear resistance while sustaining the excellent clarity of the base resin. These low haze values can be easily below 3 % – and often reach less than 2 %. “The improved performance levels of Sukano masterbatches also helps ensure no breakage of the film during edge trimming or die cut issues in the thermoforming process, while the throughput and process windows remain equivalent to conventional oil-based polymers” – states Daniel Ganz, Product Development Leader of Sukano for bioplastics applications Sukano has also recently invested in a dart impact tester equipment at their Global R&D Center in Switzerland to validate performance claims for the products to help define and quantify toughness, according to the end use application. MT bioplastics MAGAZINE [06/16] Vol. 11 31

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