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C M Y CM MY CY CMY K For the dry sterilisation trials the concentration of the sterilisation medium H 2 O 2 was set at 20 %. The resulting maximum outside temperature of the bottle was below 55°C while it was being treated. Directly after filling of the uncoated PLA bottle the residual concentration of H 2 O 2 was below 0.5 ppm and therefore in conformity with the FDA guideline. But after just one day the remaining H 2 O 2 increased to nearly 1 ppm. The test also showed that for PLASMAX coated PLA bottles the remigration of H 2 O 2 is below the detection limit of the measurement equipment (Fig. 2). These test results for PLA showed slightly higher residuals compared to the general results from PET migration tests for uncoated bottles. With regard to the bottle‘s thermal stability, the reduction of the fill weight amounts to only 0.3 % after dry sterilisation treatment, which again is comparable to PET. In the case of wet sterilisation with peracetic acid (PAA), which contains a certain amount of H 2 O 2 , no remigration of either sterilisation medium was observed. Both coated and uncoated PLA bottles were tested at 60°C rinse temperature, 1000 ppm PAA concentration and 7 seconds dwell time. As expected from the previous simulated rinse test the reduction in the fill weight after treatment is comparable to PET and amounts to 0.15 %. Conclusion When looking at thermal stability an optimised blow moulding process makes PLA bottles perfectly suitable for aseptic cold filling using either dry or wet sterilisation. Although for uncoated bottles the sterilisation residuals are slightly higher for PLA than for PET they are in the same typical range. However, in the end only an internal coating can substantially reduce this level. But even if the PLA material is suitable for aseptic filling from the point of view of bottle stability, the most critical issue remains the low barrier property of PLA against gas permeation of oxygen, CO 2 and water vapour. But here too the PLASMAX coating provides the optimum solution. Pictures: NatureWorks LLC, WZS/Kurt Fuchs, Fraunhofer ICT · · 28250 Cooperation Forum Biopolymers Raw materials - Technologies - Applications Herzogschloss Straubing 23 October 2008 Information and registration: Speakers, e.g. from BASF, DuPont, EMPA, Huhtamaki, Novamont, Teijin, TU München, Virginia Tech, will present: • Renewable raw materials for biobased polymers • Innovative technologies for manufacturing and processing • New markets for industrial applications Visit of the Competence Centre for Renewable Raw Materials in Straubing on 22 October 2008 bioplastics MAGAZINE [05/08] Vol. 3 27

Non-Food Cellulose - the first bioplastics already a century ago Container made from Biograde C 8500 CL (left) and C 9540 (right) Generation Article contributed by Dr.-Ing. Christian Bonten, Director for Technology and Marketing, FKuR Kunststoff GmbH, Willich, Germany Injection moulded sharpener made from Biograde C 9540 ZERO Non-food stock bioplastics were the very beginning As early as 1869 thermoplastic celluloid (softening temperature approx. 85 °C) was developed by J.W. Hyatt as a replacement material for ivory, intended for the production of billiard balls [1]. At that time he certainly was not aware that he had already produced the first ever bioplastic in a synthetic process. Celluloid is composed of a mixture of about 70 to 75 % by weight of cellulose di-nitrate and 25 to 30 % by weight of camphor [1]. Over the years it has been displaced by mixtures of cellulose acetate which are less combustible. Cellulose can be found as a structural component in all plants – including many plants that do not serve as food. Hence cellulose is the most frequently encountered carbohydrate on earth. Vegetable fibres such as cotton, jute, flax and hemp are cellulose in a nearly pure form [2]. By means of fiberisation and forming, it is possible to convert cellulose into paper (‘pulp’). The cellulose used here is obtained from wood or straw. By hydrolysis of cellulose, glucose is obtained, which can then be converted into different chemicals such as acetone, alcanoles, carboxylic acids, and also ethanol, by means of fermentation. This bioethanol can deliver ethylene and butadiene for the production of bioplastics. However, this method involves many different steps and is not always efficient. A simpler method is to produce derivatives from cellulose which can be converted more directly into bioplastics. The esterification to a cellulose ester with the aid of derivatives of organic acids (e. g. acid anhydride) represents a typical method. The characteristics of these cellulose esters can be strongly influenced by additives, e.g. plasticizers. The common cellulose esters CA (cellulose actetate), CAB (cellulose acetate butyrate) and CP (cellulose propionate) can be converted using all known plastics converting processes [3]. The ease of flow is excellent and even allows pin gates. Although under thermal aspects cellulose ester is more resilient than many other bioplastics, hot runners are not recommended, or at least the dwell time should be short. Vented moulds are also recommended. Biodegradable cellulose ester – made by nature! With the mission ‘Plastics – made by nature!’ the company FKuR Kunststoff GmbH was incorporated in Willich, Germany, in 2003. In cooperation with the Fraunhofer UMSICHT Institute FKuR Kunststoff GmbH has developed and established a wide range of biodegradable plastics primarily made from renewable raw materials on the market. In general biodegradable raw materials (CA, starch, PLA, PHA, PBS, etc.) are not ready-made for conversion processes, but can be tailored for the particular application by means of compounding. This processing of biodegradable raw materials requires special knowledge of both the selection of additives and a smooth compounding process. Although the FKuR product portfolio comprises more than bioplastics on the basis of cellulose, growth over recent years 28 bioplastics MAGAZINE [05/08] Vol. 3

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