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Polymers that are created by the chemical polymerization of naturally occurring monomers are becoming more attractive because of their non-toxicity, biodegradability, biocompatibility and renewability of the feedstock. Specialized lignin compounds are being developed, e.g. polyurethane foams made from renewable lignocelluloses materials. The lignocelluloses materials are converted into liquid biopolyols through liquefaction. The liquefied mixture then reacts with some chemicals to produce flexible or rigid polyurethane foams. In this work the comparison between common and bio-based polyurethane was made by measuring thermal properties. [ABSTRACT FROM AUTHOR]

Modern process control is based on the use of statistical methods to improve and ensure quality, and thus reduce the process cost due to waste and rejects. The paper deals with the process capability analysis in the manufacturing of poly(ethylene-terephthalate) bottles for packaging of table oil. PET bottles are manufactured by the procedure of injection stretch blow moulding. The preforms made by injection moulding are biaxially extruded in the blow mould, with blow parameters affecting the mechanical properties, the barrier properties and the transparency of the manufactured bottle. The performance of blow moulding machine was monitored by measuring the volumes of blown bottles. Based on the collected data, the capability analysis of the blow moulding process was conducted. [ABSTRACT FROM AUTHOR]

Natural and wood fibre plastic composites (WPC) are among the most rapidly growing markets within the plastics industry. They are manufactured by combining either wood or other natural fibers such as flax, hemp, jute or kenaf with polymers. Thermoplastic resins, such as polypropylene, polyethylene or polystyrene, are mixed with other materials (such as wood), and form a composite product. The resulting composite can be easily processed into various shapes and can be recycled. The experiments were made to study the behaviour of the wood flour-polypropylene composite during injection moulding, and to what extent the mechanical properties deteriorate after several processing cycles, i.e. mechanical recycling. Regarding efficiency of energy recovery, the heating value of wood-thermoplastic composite with different contents of wood and thermoplastics was determined as well. [ABSTRACT FROM AUTHOR]

Rapid prototyping (RP) can substantially shorten the time and reduce the cost of developing a new product from the initial idea to production. Rapid prototyping can help in recognizing the basic defects whose subsequent correction may prove very expensive, especially if they have already been made when the product is ready for production. There are also many restrictions of RP procedures, primarily in the number of available materials and their properties, which may differ significantly from the properties of end product materials. In this work, based on the stipulated standards of the 3D printing machines ( ZPrinter 310 Plus) and the hybrid Polyjet technique ( Objet Eden 330), adequate test specimens were made. Furthermore, with adequate equipment, we carried out the analysis of the dimensions, roughness of surfaces, and mechanical properties of prototype test specimens. Then, based on the data obtained by testing of properties, we provided a critical commentary regarding the data stipulated by their producers. [ABSTRACT FROM AUTHOR]