Scientific publications

Search abstracts of Borealis' scientific publications. To download pdf versions of Borealis' brochures, case studies, articles, summary data sheets, product news and presentations, please search our literature library.

Authors:	Year:	Key words:

Page: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

Title	Year
Potential of chromatographic methods for investigating the degradation pathways of polyolefin stabilizers 2009, Eva Reingruber, Markus Himmelsbach, Christian Sauer, Wolfgang Buchberger. Potential of chromatographic methods for investigating the degradation pathways of polyolefin stabilizers APST01 - Advances in Polymer Science and Technology - Linz, Austria, - (-), 2009, - Due to its excellent material properties and superior cost-performance ratio, polypropylene takes a key position in various sectors of industry such as packaging, automotive, mechanical engineering or electronics. However, the structure of polypropylene includes tertiary carbon atoms, which can easily be attacked by oxidation. This degradation causes undesirable changes such as yellowing, chalking or the deterioration of mechanical properties. Stabilizers such as phenolic antioxidants prohibit the oxidation of the tertiary carbon atoms and are therefore crucial to maintain the physical and chemical properties of polypropylene. Hence, the identification and quantification of stabilizers in polypropylene is obviously a matter of analytical concern. Several methods including thin layer chromatography, liquid chromatography coupled to various detection systems and gas chromatography have been reported in the literature. The aim of this work was to identify possible degradation pathways of stabilizers. The applicability of HPLC hyphenated with a Q-TOF mass spectrometer equipped with atmospheric pressure photo ionization (APPI) was investigated. Headspace-GC-MS was used as complementary technique to confirm the degradation mechanisms suggested by HPLC-MS. printme	2009
Warpage and Crystallinity Relations in Rotational Molding of Polypropylene 2009, Terje Glomsaker, Einar L. Hinrichsen, Åge Larsen, Petar Doshev, Espen Ommundsen. Warpage and Crystallinity Relations in Rotational Molding of Polypropylene Polymer Engineering and Science, 3 (49), 2009, 523-530 The authors present a study of the crystalline properties of selected series of polypropylene (PP) materials in relation to their warpage at conditions relevant for rotational molding. The PP materials have different crystallization temperatures and kinetics. The authors study the crystalline features of the materials using hot-press experiments and differential scanning calorimetry (DSC). In the DSC, the authors do constant cooling rate runs as well as isothermal crystallization and subsequent heating. A multimode crystallization kinetics model was fitted to the DSC cooling runs. Regression analysis was done to relate the results from the crystallization experiments to warpage. The derived empirical model shows that the crystallization temperature, crystallization half-time, and heat of fusion are the most significant parameters influencing warpage. Materials with warpage deviating from the model average are discussed taking aspects of the multimode kinetics into account. The present work could represent a basic platform for understanding and predicting the warpage during rotational molding process. printme	2009
Borstar PP for Advanced Packaging Solutions - Achieving and Retaining Transparency 2009, . Borstar PP for Advanced Packaging Solutions - Achieving and Retaining Transparency Maack 18th PEPP World Congress 2009 – Zürich, CH, - (-), 2009, - When taking a look at today’s packaging trends, several issues of general importance can be derived for the polymer producer – transparency, purity, long-term stability, low weight and convenience. Other requirements like high – glass- or metal-like – stiffness on the one hand or extreme flexibility on the other hand depend on the detail application, with toughness in a wide temperature range and the possibility for high speed processing are more common issues, again. The proper combination of Borealis’ proprietary catalyst systems and polymerization technology with market input has enabled a new generation of innovative polyolefin grades with clear advantages for both converters and consumers. The recent achievements of customer-centered polypropylene development for the packaging industry at Borealis will be illustrated by three case studies: - Sterilizable films & stand-up pouches (for applications ranging from food to medical packaging) - Transparent & tough bottles (from extrusion blow molding to injection stretch blow molding) - Convenience packaging (single-portion packaging with all-PP solutions) This is by far not the end of the road - by combining a scientific and far-sighted approach to basic problems along the “chain of knowledge” from catalyst and process to modification and conversion with the intensive communications with customers and end users of our materials, it will be possible continue to expand the application range of polyolefins significantly. printme	2009
Optimization of a compounding process for fine filler PP compounds with vacuum enhanced feeding 2009, Pablo Aguayo, Thorsten Stirner, Miriam Walddoerfer. Optimization of a compounding process for fine filler PP compounds with vacuum enhanced feeding APST01 - Advances in Polymer Science and Technology - Linz, Austria, - (-), 2009, - One of the most frequent problems found in the industrial production of polyolefin compounds is the dosing and feeding of fine and bridge-building fillers. A novel technique developed by Coperion called feed enhancement technology (FET)1 can be used to feed fine powders into an extruder without increasing the complexity of the compounding process. In this work an optimization program for a conventional compounding process with the FET on side feeders is presented. Experimental campaigns were performed on a ZSK50Mc at Coperion-Stuttgart and on a ZSK58Mc at Borealis-Linz. The compounded materials were basically PP / Rubber / Talc mixtures. In the runs the dosing of talcs with different particle size distributions was tested. The most straightforward result is a considerable throughput increase by using FET. In some cases this increase was up to 200% for very fine talc. By using this technique a bottleneck in the side feeder can be prevented. Increasing the filler intake in a compounding process and therefore the throughput an optimization of the applied torque in the extruder can be made. A preliminary assessment of mechanical properties of final compounds by screening of processing parameters like screw speed and torque load was made. In the work also an evaluation with SEM photographs of the filler dispersion using the FET and different process configurations is presented. printme	2009
PP in Automotive – The Evolution to an Engineering Thermoplastics: The Key Role of Material Innovations and latest Application Implementations 2009, Harald Hammer. PP in Automotive – The Evolution to an Engineering Thermoplastics: The Key Role of Material Innovations and latest Application Implementations APST01 - Advances in Polymer Science and Technology - Linz, Austria, - (-), 2009, - The component requirements for the automotive industry (e.g. mechanical properties, surface aesthetics,processing, emissions) increase constantly, requiring a permanent upgrade of material performance. With this, the importance of RTPO base resins will increase as well - key needs will already be addressed in the base resin to customize RTPO properties. Some recent examples for material innovations are presented: - C-class interior - Smart, BMW X5 body panels - BMW 7 series instrument panel carrier An outlook on PP evolution is given by sketching the option of one PP solution for SMC replacement in Exterior Body Panels. printme	2009
Shear and elongational flow behavior of acrylic thickener solutions. Part II: effect of gel content 2009, Saeid Kheirandish, Ilshat Gubaydullin, Norbert Willenbacher. Shear and elongational flow behavior of acrylic thickener solutions. Part II: effect of gel content Rheologica Acta, 4 (48), 2009, 397-407 We have investigated the effect of crosslink density on shear and elongational flow properties of alkali-swellable acrylic thickener solutions using a mixing series of the two commercial thickeners Sterocoll FD and Sterocoll D as model system. Linear viscoelastic moduli show a smooth transition from weakly elastic to gel-like behavior. Steady shear data are very well described by a single mode Giesekus model at all mixing ratios. Extensional flow behavior has been characterized using the CaBER technique. Corresponding decay of filament diameter is also well fitted by the Giesekus model, except for the highest crosslink densities, when filament deformation is highly non-uniform, but the non-linearity parameter a, which is independent of the mixing ratio, is two orders of magnitude higher in shear compared to elongational flow. Shear relaxation times increase by orders of magnitude, but the characteristic elongational relaxation time decreases weakly, as gel content increases. Accordingly, variation of gel content is a valuable tool to adjust the low shear viscosity in a wide range while keeping extensional flow resistance essentially constant. printme	2009
New measurement method for appearance of flow marks or tiger stripes defect for improved quantification and analysis 2009, Sybille Frank, Robert Gahleitner, Kurt Niel, Klaus Bernreitner, Christelle Grein, GÃ¼nther Gsellmann, Harald Herbst. New measurement method for appearance of flow marks or tiger stripes defect for improved quantification and analysis PPS 25 - Intern.Conf, of the Polymer Processing Society, - (-), 2009, - A well known surface defect called flow marks results in shiny dull bands roughly perpendicular to the flow direction, the origin of the defect still not being completely understood. That defect appears on different types of material like PP, PP/EPR/talc blends or PC/ABS blends [3],[5] hence flow marks are not unique to rubber modified material since homopolymers like PP also display the phenomena under various melt conditions. As the defect causes an unaesthetic surface appearance making the material unsuitable for unpainted surfaces, a huge research effort to resolve the problem of flow marks will be more and more relevant. For this reason a qualitative analysis of this defect is a must. Up to now no measurement method for detecting flow marks and a quantitative estimation has existed. Therefore a measurement setup was developed which allows an improved analysis in a precise and reproducible manner. Furthermore this means that an objective classification is available which offers the possibility for new kind of evaluation of this effect. Ageing and artificial weathering analysis were performed on injection moulded plates with different pronounced flow marks on untreated plates in order to analyse the influence of the different conditioning steps. It could be observed that sample preparation, e.g. injection speed, has a strong effect on the occurrence of the defect after annealing. Furthermore the method was used to develop material with enhanced surface properties. printme	2009
Evaluating and projecting the strategic and financial value of your patent portfolio 2009, Markus Gahleitner, Erik van Praet. Evaluating and projecting the strategic and financial value of your patent portfolio Nordic IPR Forum 2009, - (-), 2009, - As a leading provider of innovative polymer solutions, Borealis has significantly improved its Intellectual Property Rights (IPR) position in recent years. An important element for this was an integrated portfolio strategy aligned across both the central Innovation and Technology (InnoTech) department and the business units of the company. This system provides guidance for decisions regarding development, protection, licensing and oppositions, making sure that both InnoTech and IPR investments are well placed. printme	2009
Polyolefin blends with linear and long-chain branched components: 2009, Tung Pham, Markus Gahleitner, Manfred Stadlbauer. Polyolefin blends with linear and long-chain branched components: PPS 25 - Int.Conf. of the Polymer Processing Society, - (-), 2009, - For special conversion processes like foaming or extrusion coating, polyolefins require a certain level of strain hardening associated with a long-chain branched polymer structure. This is inherently present for low-density polyethylene (LDPE), but not for polypropylene (PP), which has a number of mechanical advantages. For this purpose, a reactive modification process to generate long-chain branched PP (LCB-PP or HMS-PP) has been established, which could not be expanded to high-impact copolymers with ethylene. For combining strain hardening with low-temperature impact strength, polyolefin blends consisting of LDPE, HMS-PP and a linear high-impact PP copolymer acting as compatibilizer were developed. The structure-property relations of these complex materials, exemplified by a number of analytical, rheological and mechanical characterization techniques, demonstrate ways of modern material development. A material for producing foams and paper coatings having a wide application temperature range could be developed. printme	2009
Nonlinear Rheology and Miscibility of Polyolefin Melts 2009, Saeid Kheirandish, Dietrich Gloger, Christelle Grein. Nonlinear Rheology and Miscibility of Polyolefin Melts DRG Annual Meeting, - (-), 2009, - The relation between miscibility / immiscibility effects in polyolefin blends and processing problems is outlined. Rheological methods for detecting such miscibility effects in an early stage are discussed. printme	2009