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The majority of geotextiles are made of polymers from the family of polyolefin, polyester, or polyamide, which have environmental issues connected to soil pollution. Geotextile can be used for at least one of the following functions-reinforcement, filtration, separation, drainage, stabilization, fluid barrier, and sea front structures. Geotextiles are frequently used in geotechnical engineering for slope protection, drainage systems, and soft foundation reinforcement due to their high strength, low cost, and ease of usage. The composition and use of geotextiles in geotechnical engineering are reviewed in this work. The subject also shifts to the most current advancements in geotextiles, with a focus on green geotextiles, intelligent geotextiles, and high-performance geotextiles, based on literature that includes the most recent data. [ABSTRACT FROM AUTHOR]

Starting from the growing importance of polymer recycling, and the dominant role of polyolefins as materials with low carbon footprint and wide application range, the issues of mechanical recycling of polyethylenes and polypropylenes are discussed. Limited compatibility creates challenges when "Closing the loop", but Borealis and its partners in the circular economy field are developing advanced recycling technologies, for which not only improved sorting and quality control, but also the use of advanced copolymers for improving compatibility, processabilty and mechanics is being studied. The application of multi-phase impact copolymers is shown to be especially efficient, while also being much more economical than special compatibilizers or impact modifiers, which also tend to excessively reduce the modulus of the resulting compositions. A thorough understanding of the structure-property relations underlying the upgrading process is clearly required, and a wide range of applications – from advance packaging to automotive – can be covered consequently. [ABSTRACT FROM AUTHOR]

The "oxidation induction time/temperature" (OIT), measured with a differential scanning calorimeter (DSC), can be utilized as incoming feedstock characterization method, to classify virgin and post-consumer polypropylene (PP) concerning their oxidative stability using the ISO-11357-6 OIT standard, both isothermally and dynamically. Because the OITime is significantly dependent on different sample preparation methods, the results of oxidative stability with a time-dependent degradation exhibited great variability during testing. An increased variation in OITime measurement results was observed during investigation of films and samples with brought-in warpage through cutting compared to non-oriented materials. Therefore, the aim of this work was to propose an alternative, robust and easily reproducible preparation and testing method based on the norm to expand the scope and to find influences of reproducible measurability of virgin as well as post-consumer PP. The examined samples prepared for the isothermal OIT-measurements varied in geometry, preprocessing as well as the conducted DSC measurement program. Investigations show that a major factor of reproducibility is a uniform sample-to-oxygen surface, represented by the diameter. Thermostimulated deformation effects, commonly observed in oriented polyolefin products when heated, can lead to a temporary deformation of OIT samples during measurements inside the aluminum pan, followed by an altered sample surface exposed to oxygen. Concluding the experiments conducted, the ISO-OIT standard is capable of reproducible results but should be queried when effects altering the material surface are possible. Considering the consequent fluctuating results, an expansion of a reproducible OITime measurement is proposed. [ABSTRACT FROM AUTHOR]

Thermoforming is very sensitive regarding the used material especially when it comes to recycled materials. With the "design from recycling" approach and the consideration of a multilayer structure, post-consumer polypropylene recyclates (rPP) could be used for thermoformed cups/containers. Due to insufficient sorting techniques, the problem of cross-contamination with the respective other polyolefin polyethylene (PE) occurs in rPP. It has been evaluated that the remaining PE content is strongly influencing the properties of thermoformed products. While it can be assumed that there is a positive impact on toughness, properties like the stackability or the shrinkage of the cups will be negatively affected. Therefore, methods for characterization of the PE content have been used for developing correlations allowing for quality control in the production. Several correlations have been found which enable the prediction of product properties by only testing input material properties. Thermal characterization methods are sensitive to the PE content and were hence used to predict the shrinkage profile of the thermoformed product. The results show the importance of structure-property relationships and illustrate the possibility of process adjustments based on a profound material understanding. [ABSTRACT FROM AUTHOR]

The rheological and self-healing behavior of a class of catalytically synthesized amine functionalized polyolefins is investigated. These materials possess tunable rheological properties and display autonomous self-healing. The linear viscoelastic properties are modelled using a tube based Time Marching Algorithm to calculate several model parameters that describe the individual chain dynamics. The self-healing response is described by findings from the reptation model as well as recent theory on associating polymer networks with reversible bonds. [ABSTRACT FROM AUTHOR]

The oxygen and carbon dioxide permeability of the packaging plastic films is a very important parameter in the Modified Atmosphere Storage of agricultural products. A study was conducted to determine the influences of the type and thickness of packaging plastic films against oxygen and carbon dioxide. The materials used in this research consisted of Polyethylene (PE) and Polypropylene (PP) in three different thicknesses. Permeability measurements of the plastic films were carried out based on the Kubik and Zeman method with some modifications. The results showed that the type and thickness of the plastic film significantly influenced the transport properties of the plastic film consisted of the permeability against oxygen, carbon dioxide and the ratio of those two values (p<0.05). However, there was no significant interaction effect of the two factors on the transport properties of the plastic film tested (p<0.05). These findings indicated that permeability values against oxygen and carbon dioxide are solely depended on the type or thickness of the plastic film. It was also known that PE plastic film had larger values of both PO2, PCO2, and β than PP and was found to be significantly different (p<0.05). The values of β of the tested plastic film were found to be suitable for packaging fresh agricultural produce. [ABSTRACT FROM AUTHOR]

Perforated macrocellular foams produced using recyclable polyolefin resins have existed as acoustic absorption panels for almost 20 years. They have broad acoustic absorption with good resistance to moisture, salt, and UV exposure. Adoption of In-Situ sound reflection standards, in the Rail and Road noise barrier industry; along with renewed focus on sustainable design has led to fresh interest in this technology. Traditional foam panel formats did not attain acceptable insitu sound reflection performance. The purpose of this study was to evaluate an improved structure of foam to the industry norms required of absorptive components of the noise barrier wall; and then subject this to a lifecycle analysis. A new structure showed good reflection results in-situ, using a reduced mass of raw material. The novel panel was evaluated to a range of acoustic and mechanical testing standards to assess suitability for adoption in Noise Barrier Wall applications. The material was subsequently subjected to lifecycle analysis and the resulting product issued with an environmental product declaration. This paper concludes that the new material is well suited to widespread use in in-situ category A3 noise barrier walls. [ABSTRACT FROM AUTHOR]

In the nomenclature of functional composite materials based on regenerated polyolefins, a special place belongs to tribotechnical and protective composites used in various branches of mechanical engineering, in the production of non-ferrous metal products by injection molding, in tribosystems operated in road construction technological equipment and mining. Taking into account the variety of structural design of metal-polymer systems and their exploitation conditions, it is necessary to develop a range of means for increasing the maintenance life. Optimal compositions are selected and parameters of their process characteristics are estimated in this work. [ABSTRACT FROM AUTHOR]

Recycled plastics contain volatile compounds from materials degradation as well as from other sources, besides monomer and oligomer residues from the polymerisation process. These volatile compounds cause smell and emissions, which have a negative impact on materials quality. For some applications, e.g. for automotive interior, smell and emissions are critical, thus limiting the use of recyclates there. A degassing step in a co-rotating twin screw extruder is a possible way to reduce these emissions. Therefore, the aim of this work was to investigate the influence of melt processing on the mechanical properties and the emissions of a recycled post-consumer polyolefin mixture. Different screw configurations, process parameters and degassing variations, also with additives to improve degassing, are used. The influence of the process on the emissions was tested by headspace gas chromatography (VDA 277). Also, tensile and impact properties were recorded to see if there is an influence of the processing. Oxygen induction time was evaluated to check for the degradation of the stabilizer during the process. These results were compared with the ones for virgin polypropylene. The first results show that the emissions can be reduced to one third of the untreated recyclate with the degassing process. The sum of the emissions and mechanical properties show some dependence on different screw configurations, process parameters and degassing methods. Further steps are to investigate the emission testing method, especially the influence of sample preparation and test parameters, more in detail and to validate these results. [ABSTRACT FROM AUTHOR]

We present a method to optically model prototypes pre- and post-manufacturing to incorporate material flaws and understand clearly the potential of designs at the prototyping stage of window integrated PV systems. A prototype Window Embedded Crossed Compound Parabolic Concentrator (WE-CCPC) made of plastic Topaz optics, arrayed within double glazed windows as a means to provide both electricity and natural sunlight to a building is presented. The outdoor performance of the prototype is characterized, and the theoretical and experimental results compared. The manufactured module was found to have an optical efficiency of 77% at normal incidence and an acceptance angle of 20° once realistic material and manufacturing considerations were incorporated. Optical losses such as the absorption, cell reflectance, slope errors and irradiance nonuniformity were found to decrease the acceptance angle significantly as all increase with increased incidence angle, accumulating to the ~15° of acceptance angle loss from the original modelling. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the modification of talcum and its support as crosslinking agent for polyolefins. To improve the crosslinking of polyolefin chains a thermal initiator is linked to the talcum surface. During the extrusion process the initiator decomposes and radicals are formed. These radicals will start and support crosslinking between the polymer chains. To produce crosslinked polymers, two steps were necessary. The first step was the modification of the mineral filler. For that purpose alkoxysilanes were grafted onto the talcum surface. After that, the initiator was linked to the silanes grafted onto the talcum surface. To prove the active molecular components on the particles, the silanized and modified talcums were characterized with different measurement methods such as x-ray photoelectron spectroscopy, infrared spectroscopy and thermogravimetric measurement. The second step were the crosslinking experiments with the modified talcum in polyolefins. Compounds of polyolefins and modified talcum were kneaded, plates were compression molded and analyzed with a plate/plate rheometer regarding their crosslinking behavior. [ABSTRACT FROM AUTHOR]

The pursuit of sustainable packaging strategies has prompted a significant focus on mono-material structures within flexible packaging, an essential domain for improving recycling initiatives and advancing a circular economy. This poster explores the potential of mono-material flexible packaging to markedly diminish environmental impacts by streamlining the recycling process and reducing material waste. Traditionally, flexible packaging relies on multi-material laminates that combine various polymers, complicating recycling efforts and frequently resulting in non-recyclable materials. In contrast, mono-material structures consist of a single polymer type, facilitating easier sorting and processing at recycling facilities. This shift enhances the recyclability of packaging materials and preserves the essential functional properties needed for food safety and product integrity. We will highlight recent advancements in polymer technology, showcasing innovations in barrier properties and mechanical strength that empower mono-material flexible packaging to rival traditional multi-material alternatives. Additionally, this poster will present case studies of successful implementations of mono-material designs in food and consumer goods packaging, underscoring their environmental benefits alongside performance improvements. Through these findings, we aim to demonstrate the transformative potential of mono-materials in fostering a sustainable packaging future. [ABSTRACT FROM AUTHOR]

Polyolefins, which include polyethylene (PE) and polypropylene (PP), account for 50% of the world's total plastic production. Despite this significant share, the global recycling rate for polyolefins remains remarkably low at around 8%. This presents a major challenge, especially as polypropylene (PP) production alone is expected to reach 120 million tons by 2024, representing a trade volume of $115 billion. Several recycling technologies exist for polyolefins, each with its advantages and limitations, where mechanically recycling appears as the most energy-efficient method, although downgrading of material properties via degradation of the polymer chains over multiple cycles or contamination and mixed waste streams are the main challenges leading to reduced mechanical strength of the final product, narrower range of applications. Mechanical recycling of complex structured materials (multi-layered polymers or composites) or contaminated plastics and mixed plastic streams is yet another challenge, where pyrolysis seems as a viable option as a process in order to break down polyolefins into smaller hydrocarbons, although it is highly energy-intensive, bringing the risk of harmful emissions aside if not properly controlled. Solvent-based recycling (SBR), also known as dissolution, selectively dissolves polyolefins in specific solvents, separating them from contaminants without breaking the polymer chains. This process preserves the polymer's mechanical properties, enabling the production of highquality recycled materials. It also works well for contaminated or multilayer plastic waste, which is difficult for mechanical recycling. SBR-based PP recycling process developed through the collaboration between Sabanci University and Kordsa offers works with much less pressures and more importantly with bio-solvents. Lab scale studies have given promising results and pilot line for to process is almost ready to operate. With that, high quality, less energy consuming and price- competitive recycled virgin-like polyolefins will be offered to the market. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the crosslinking of different polyolefins with the support of a modified mineral filler. The modified filler, talcum, acts as a crosslinking agent and improves the crosslinking network. Therefore, a thermal initiator is linked to the talcum surface. During the extrusion process, the initiator decomposes and radicals are formed. These radicals support the crosslinking process between the polymer chains. To produce the crosslinking agent, two steps were necessary. The first step was the grafting of alkoxysilanes onto the talcum surface. The next step was the linking between the initiator and the silanes grafted onto the talcum surface. To optimize the crosslinking network, two different polyolefin blends were used. The aim was to investigate the influence of the different chain branching behavior of the polymer network on the crosslinking process. Therefore, compression molded plates out of the polymer blends and the modified talcum were produced and analyzed with a plate/plate rheometer. [ABSTRACT FROM AUTHOR]

Toughening of homopolymer polypropylene (PPH) in the post reactor step by incorporating external elastomers has become an attractive area of research. In this investigative work, PPH was post-reactor blended with different types of Polyolefin elastomers (POE) that were selected based on the co-monomer type and density. The performance behavior of PPH/POE blends with and without a nucleating agent was compared to in situ (in the reactor) modified PPH with Ethylene Propylene Rubber (EPR). The addition of POE in PPH, increased toughness at room temperature and the stiffness of the blends decreased. The addition of a nucleating agent was noted to improve the toughness and stiffness compared to their non-nucleated counterparts, while the tensile strength remained unchanged. At -20 °C, the impact strength results showed no significant improvement in PPH/POE blends with and without addition of the nucleating agent. The morphology analysis have shown clearly phase separation of the blends components thus demonstrating the immiscibility of the blend systems. The addition of the nucleating agent was seen to decrease the domain size of POE phase thus leading to the improvement in the toughness properties of the blends. ICP materials have shown better mechanical properties and more uniform rubber dispersion than the blends system. The rheological results of PPH/POE blends based on POE1 (butene co-monomer) and POE4 (octene co-monomer) indicate that increase POE content leads to an increase in the blends viscosity across the shear range. However, the trend was different in blends containing copolymers POE2 and POE3. [ABSTRACT FROM AUTHOR]

The work presented here describes the development of controlled release and affordable mosquito repellent bicomponent polymer filaments. These filaments may be used in the production of alternative malaria vector control interventions aimed at reducing outdoor malaria transmission in resource-limited communities. The approach was to develop a bicomponent polymer filament with a core containing the volatile repellent active and an outer membrane layer that reduces the rate at which a volatile active is released to the atmosphere. The bicomponent filament was produced by a simple melt extrusion and drawing process. The core polymer used was poly(ethylene-co-vinyl acetate) (EVA) and the sheath polymer was high density polyethylene (HDPE). 40 wt.% N,N-Diethyl-m-toluamide (DEET) was incorporated into the EVA via a simple absorption process at a temperature of approximately 81 °C. Scanning electron microscopy (SEM) studies indicated that a bicomponent core-sheath structure was successfully formed by the melt extrusion and drawing process. Raman studies showed that a concentration gradient developed across the bicomponent filament after the manufacturing process. The Raman results suggest that the release of the repellent from the bicomponent filament is a diffusion controlled process, a characteristic of controlled release. With these findings, the study should proceed to the upscale of repellent impregnated bicomponent yarn production and fabric knitting. Such a fabric can be further studied for effectivenes in reducing outdoor malaria transmission in laboratory and field trials. [ABSTRACT FROM AUTHOR]

In this study we have studied and compared the physical and mechanical features of two adhesive materials, polyethylene (PE) based, employed as adhesive films for glasses in solar photovoltaic cells. The two polymeric films are in formulations with chemical functional molecules: one is a cross-linkable PE and the other is a ionomeric PE resin. Their adhesion strength was characterized by lap shear tests at three different temperatures. Thermal characterization (by DSC and TGA analysis), wet ability and gas diffusivity measurements have been also performed. Experimental results highlighted that cross-linked PE exhibited a better mechanical adhesive features than the ionomeric resin, beside a lower wet ability toward water molecules, gas barrier and thermal stability, all features required as sealant in the solar cells. [ABSTRACT FROM AUTHOR]

Continuous fiber-reinforced thermoplastics feature key advantages over thermoset composites. However, extensive use of thermoplastic matrices has been restricted by processing challenges, including high melt viscosities and melting temperatures. In this work, we investigate an approach for improving thermoplastic prepreg processability and conformability by fabricating prepreg with partially polymerized thermoplastic matrix. We describe a case study of a prepreg composed of carbon fiber fabric and acrylic (polymethylmethacrylate) resin. The chemical and rheological kinetics of neat acrylic resin were investigated, followed by pre-polymer aging studies. Moreover, the optimal extent of polymerization (degree of monomer conversion) for the prepreg was determined by constructing a prepreg fabrication map. Prepreg samples were fabricated using labscale methods, and characterized to demonstrate tack at room temperature. Manufactured prepreg was thermoformed below the final glass transition temperature of the matrix with minimal pressure for porosity analysis. Polymerization kinetics data showed that auto-acceleration from the Trommsdorff effect plays a key role in both rate of polymerization and viscosity evolutions, while the aging studies indicated that refrigeration can delay room temperature aging of acrylic prepolymer resin. Overall, the laminates thermoformed with partially polymerized thermoplastic prepregs exhibited low porosity with no sign of bulk porosity or resin-deprived regions. This work highlights some potential advantages of the new thermoplastic prepreg, which emerges from the ability to utilize conventional thermoset prepreg processing capacities to manufacture thermoplastic composites, and identifies processing challenges that should be addressed. [ABSTRACT FROM AUTHOR]

Increasing the economical efficiency of single screw extrusion is an important factor in the area of research and development in extrusion technology. Enlarging processing machines is an approach which raises the mass flow rate but at the same time increases costs for maintenance or batch changes. This is why the focus of this essay lays on an increasing speed at a constant diameter, in order to improve the output. Investigations with polyolefins show that in terms of high-speed extrusion (from 2m/s on) particular attention has to be paid on the partially poor feed behavior and high processing temperatures. Based on the results of previous studies, the investigation of amorphous thermoplastics (polycarbonate) in combination with high-speed extruders is promoted at the KTP institute. Due to the different molecular structure from amorphous to partially crystalline (polyolefin) it can be assumed that the state of knowledge in areas of feed behavior, temperature development or mixing homogeneity can be transferred only partially. The reason for the lack of melting is the enthalpy of amorphous polymers. This essay introduces the first observations of temperature homogeneity and pressure development partially at high-speed extrusion with polycarbonate. These observations are based on the evaluation of various speed ranges on an extruder (D = 30 mm) with vacuum degassing and torque direct drive. The measurements occur with a temperature sensor in the area of the screw tip and with several pressure sensors along the axial screw length. This arrangement allows making a statement about temperature homogeneity, pressure development and the melting process. Based on these results, approaches to process optimization are introduced. [ABSTRACT FROM AUTHOR]

A numerical simulation with correlation between the stretch blow moulding process parameters and the eventual room temperature mechanical properties of the formed PET (Polyethylene Terephthalate) bottle enables the bottle manufacturers to optimize the design of the preform and the mechanical performance of the bottle. In this study PET samples were processed at conditions relevant to stretch blow moulding process and subsequently Young's moduli at room temperature were determined from the uniaxial tensile tests. A correlation was established between the network stretch of the Buckley material model and the Young's modulus. [ABSTRACT FROM AUTHOR]

The investigation of the shear-induced crystallization of isotactic polypropylene in isothermal conditions in different shear regimes is the aim of the present research. A multiscale framework is developed and implemented to compute the nucleation and growth of spherulites, based on material parameters needed to connect crystallization kinetics to the molecular material properties. The framework consists of a macro-model based on a Finite Element Method linked to a micro-model based on Cellular Automata. The main results are the evolution of the crystallization degree and spherulite space filling as a function of imposed temperature ash shear rate. [ABSTRACT FROM AUTHOR]

This work addresses the potential of polypropylene, neat (PP) and reinforced with short glass fibers (GRPP), as a candidate for the Fused Filament Fabrication (FFF)-based 3D printing technique. The entire production chain was evaluated, i.e., starting with PP and GRPP pellets, filaments were produced by extrusion and test samples were printed in different process conditions (different layers' thicknesses, deposition orientation and infill) with the in-house produced filaments. This strategy enabled a true comparison between parts printed (FFF) with parts manufactured by compression molding (CM), using exactly the same grade of raw material. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyse the forming behaviour of glass fibre reinforced polypropylene and to identify the influence of several process parameters on the resulting part quality. For this purpose, a complex forming tool was designed, consisting of several areas with single and double curvature. The specimens were produced from unidirectional (UD) tape using the Fiberforge RELAY2000® automated tape laying machine and a subsequent consolidation step. They were then fixed in a support frame, pre-heated in an infrared oven, and formed in the forming tool, which was mounted into a hydraulic heating press. The investigated process parameters were the number and force of the springs in the support frame, the tool temperature and the forming pressure and speed. The layups of the specimens were [0/90/0/90/0]s and [0/45/90/-45/0]s. After the forming process, the parts were analysed in terms of their quality, with a special focus on wrinkles, undulations, gaps and surface roughness. In addition to optical analysis with a statistical evaluation of the results, 3D scans of the specimens at different steps of the forming process were made to gain an impression of the forming mechanisms and the development of failures. The ATOS system of GOM was used for these 3D scans. The results show that the undulations were influenced by the tool temperature and the spring force. By contrast, the surface quality was most strongly dependent on the forming pressure, which also influenced the size and the number of gaps. The forming speed affected the gaps as well. The tool temperature had the largest influence on the development of wrinkles. As expected, the quasi-isotropic layup showed distinctly more wrinkles and undulations, but it also presented a better surface quality than the orthotropic layup. [ABSTRACT FROM AUTHOR]

The methods of visual and instrumental express diagnostics of safety critical defects and non-uniform thickness of transparent mono- and multilayer polyolefin surface coating of metal items are analyzed in the paper. The instrumental diagnostics method relates to colorimetric measuring based on effects, which appear in the polarized light for extrusion polymer coatings. A color coordinates dependence (in the color system CIE La*b*) on both HDPE / PVC coating thickness fluctuation values (from average ones) and coating interlayer or adhesion layer delaminating is shown. A variation of color characteristics in the polarized light at a liquid penetration into delaminated polymer layers is found. Measuring parameters and critical uncertainties are defined. [ABSTRACT FROM AUTHOR]

Polymer modification by radiation grafting of monomers onto polymers has received much attention recently. In the current study, γ-irradiation technique was used to achieve graft copolymerization of maleic anhydride (MA) onto low-density polyethylene (LDPE). To optimize, the process was performed at different γ-irradiation doses and MA concentration. The microstructure of grafted polymer film has been characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, field emission-scanning electron microscopy, and atomic force microscopy. The studies performed made possible the selection of experimental protocols adequate for the production of new copolymeric materials with high grafting yield. [ABSTRACT FROM AUTHOR]

Taylor rod-on-anvil impact experiments have been performed on a range of polyolefins. At impact velocity greater than ~250 m/s there are significant differences observed in the deformation behavior between the four polymers, which cannot be explained based on current understanding. During the initial stages of impact, mechno-luminescence is observed in all polymers and at all impact velocities. The location and length scale of this luminescence is consistent with the observed location of temperature increases that approach, and in some instances, exceed the melt point of the polymers. [ABSTRACT FROM AUTHOR]

The results of research onstrength of welded socket joints of polypropylene pipes are presented in this article. Welding is performed at various air temperatures including low temperatures on the developed technology. The test results demonstrate efficiency of the developed technology of socket welding of polypropylene pipes at low temperatures. [ABSTRACT FROM AUTHOR]

The similar densities of polyethylene (PE) and polypropylene (PP), complicate the separation for these materials in the mechanical recycling of post-consumer plastics. Therefore, recycled mixed polyolefins (rMPO) are widely available as recycled (r) polymer material. These blends are commonly cheaper, but also inferior in properties to relatively pure waste streams of rPP or rPE. In order to improve these materials, blends of rMPO were made with more expensive, relatively high quality rPP. This approach was purposefully 'bottom up', exploring how to upcycle the lower grade rMPO instead of downcycling higher grade rPP with a measure of added (cheaper) rMPO. Blends were made with two types of rMPO, the one a HDPE-PP blends from hard plastic waste and the other a LDPE-HDPE-PP blends, based mostly on foil materials. Each of these materials had one type of mechanical property in common with the high quality rPP, these being Young's modulus and toughness respectively. Blends were made at different concentrations (0-50% in steps of 10%) and injection moulded into test samples. Density, MFI, mechanical strength, impact toughness and transition temperatures were experimentally determined for each blend. It was evaluated in how far the law-of-mixtures could apply to these blends and for those occurences where it did not, practical rules-of-thumb were composed. [ABSTRACT FROM AUTHOR]