Research Database: Projects

The construction of high quality polymer products, bondings and composite materials requires: wide knowlegde about the materials used reliable quality control for incoming and outgoing products high process safety reliable suppliers Already for construction planing, proper materials have to be chosen. Not only the final price, but also the material properties such as the possible strain or influences by surrounding media have to be taken into account. In case the material fails during the fabrication, a lot of problems and costs may arrise. Material faliure may disturbe the whole construction process and even may influence subsequent orders, especially when productions runs 24/7 and "just in time". And this is where not only the source of failure, but also responsibilities has to be clarified. At this point, failure analysis can help to find which parameters led to the final material collapse. But which of the high variety of methods is the right one? How can I minimize the number of analyses and costs and get the fastest results? Aim of this Project is to teach strengths and weaknesses of the most important polymer analysis methods. The most common applications in terms of polymers, composite materials and adhesions are demonstrated with special respect for failure analysis and quality assurance.  This includes the following analysis methods: Microscopic methods (light, digital and SEM) thermic analysis methods (DSC, DMA and DEA) mechanical analysis (static and dynamic) special polymer analysis methods (pyrolysis GC-MS, SPME-GC-MS, RFA, FT-IR, XRD, etc.)

Industrial robots could be used with higher efficiency than before due to today's technical improvements. But for the sake of accident prevention they still work almost exclusively "under themselves". People have to be kept out of their working area by means of fences or the working speed of the robots has to be reduced considerably, if people are in danger, for example during robot maintenance.

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The use of FEM structural analysis for the development of extrusion blow mouldered parts is state of the art. Product properties like stackability can be predicted with high accuracy. Though, it is involving to determine material parameter necessary to give a significant simulation. Due to material stretching during the blow moulding process combined with high cooling rates, the properties of thermoplast materials is influenced significantly. Therefore it is not possible to refer to data from literature; instead, for each material all parameters have to be determined experimentally. Transferring these parameters to other materials or process conditions hardly possible. The reason for this is the lacking basic knowledge on a molecular scale. The coupling of already existing macroscopic models with those in micro scale offers new possibilites: Influences of the manufacturing process on the polymers, resulting in changes of the material properties, become clearer when the molecular details are studied. With the help of computer simulation, basic microscopic knowledge can be transferred into macrosopic information. The main goal is to create a completely process based material model with the help of simulation models on micro scale as well as extensice studies.

The aim of this project is to improve the efficiency for materials and resources of blow mouldering parts and packaging products below 3 liters. This shall be realised via optimisation of theoretical valuations like the FEM structure analysis. Integral properties can so be foreseen in the stage of development. Nevertheless, it is also necessary to improve the facturing hardware, so that the theoretically calculated thicknesses can be realised. Not only the development of new simulation methods, for example to simulate filling processes or the pinch-off weld, but also the material properties are in the main focus. The influnce of process parameters such as wall thickness degree of torsion and degree of orientation cooling rate are investigated and implemented into the simulation models

After the change of government in NRW in 2011 the extension of wind energy became a vital political topic. Untill 2020, 15 percent of the electric consumption in NRW shall be based on wind power; currently it is only about four percent. With the latest law from July 2011 ("Windenergieerlass") and further counselling offers (EnergieAgentur.NRW, Netzwerk Windkraft) the government tries to support the expansion of wind power stations as well as planing projects with local communes.  Even though the energy revolution, renewable energy or wind power are supported in public, the construction of new power stations or "repowering" (replacing old stations by new and more efficient ones) also encounters resistance. Lacking acceptance may cause delays which will lead to higher costs. At the very beginning conversations have been hold with the EnergieAgentur.NRW and experts for wind power (Netzwerk Windkraft). They affirmed that research about the acceptance of wind power will be important for policy, the communes, but also for the citizens. EnergieAgentur.NRW offered their support for the pilot study by conveying this project to the deputy major of the selected commune. According to literature, acceptance is influenced by many factor. Its strength depends on the object and subject of accepteance as well as on the context. The goal of this pilot project is to establish a groundwork for acceptance research and to analyse communication as a measure for public acceptance. The reporting of the public media, which has found only little attention to this date, will now stand in focus. The way how media reported about the construction of new wind parks and the resulting influence on the acceptance of energy projects is the main goal.

The aim of this project is make use of clinker reduced Portland cements in order to reduce the energy input during production and therfore also the CO2 emission. This is realised via a syergetic activation of puzzolans. Using the metacaolin Metaver could reduce the Portland cement input by 25% without a considerable reduction of the resulting bending tensile strength. Only the compressive strength lowered about 10 - 15%. Conducting Life-Cycle-Assesments already during the project made it possible to take an immediate impact on the costs and the Global Warming Potential (GWP).  

The aim of this project is to develop an individualised and functional carrier material for bone defects. The main focus is put on the multi-step development of an individualised, functional carrier material the osteogene differentiation by external factors (CD73, P1 receptors) the use of adult stem cells for the differentiation of osteoblasts the synthesis of new carrier material und their chemical modifications

Lignin is one of the most important components of all plants (about 30% in wood), right after cellulose. Worldwide about 50 million tons of techniqually isolated lignins are gained during pulp production but only 2% of it is acutally used. Aim of this project is to recycle and modify the lignin "waste" so that lignin based polymers can be generated and used for building issues. About 25% of all synthetic materials are used in the construction sector. Foams are almost exclusively based on fossil sources, e.g. Polystyrene insulants or Polyurethan (PU)-foams. Due to the steady improvement of insulants for office as well as for private buildings, the demand is rising continously. Here, also lignin could play an important role in the future: Mostly used for energetic issues, it could now find application as a mechanical alternative for improved insulations. The distinct adherance properties of lignin can be used to produce lignin based construction material, e.g. for better sound insulation. Moreover, the recycled lignin can be tested as a substituent in glues or binding agents instead of phenol.  

The aim of this project is to investigate the hardening process of light-curing dental filling components. This is realised by tracking the process in real time with the help of the dielectric analysis (DEA). This method enables to track the behaviour of resins while hardening in the electric alternating field. The DEA is method that is used frequently, mostly in the aerospace and automotive industry, but less in the dental fields. Due to its great resolution in time and its sensitivity the DEA can be used for fast initiation processes as well as for slow post-curing processes after light exposure.  The goal is to learn more about the hardening processes and their different parameters, e.g. reaction temperature, resing compostition, viscosity, light intensity and depth of radiation. This data is crucial for kinetic modelling of polymerisation and hardening processes.