Projects / Programmes
Intelligent polymeric materials and technologies
January 1, 2009
- December 31, 2014
| Code |
Science |
Field |
Subfield |
| 2.04.00 |
Engineering sciences and technologies |
Materials science and technology |
|
| 2.05.00 |
Engineering sciences and technologies |
Mechanics |
|
| Code |
Science |
Field |
| T390 |
Technological sciences |
Polymer technology, biopolymers |
| Code |
Science |
Field |
| 2.05 |
Engineering and Technology |
Materials engineering |
polymeric materials, macro- and nano-composites, intelligent behavior, multiscale phenomena, time-dependent behavior of materials and structural elements, constitutive modeling, effect of pressure, temperature, moisture, and mechanical loading, processing technology
Researchers (16)
Organisations (1)
Abstract
For many years the research group has been studying the behavior of time-dependent materials, especially polymers and polymer based composites.During the manufacturing process the polymeric materials are usually exposed to extreme and rapid changes of temperature and pressure.In this process the formation of the material structure takes place, which finally defines the behavior of the material in solid state. The nonlinear viscoelastic model 'Knauss-Emri', developed by our group, enables modeling of the macroscopic behavior of polymers exposed to different boundary conditions (pressure, temperature, moisture, and mechanical loading) during the production process and later in exploitation.
The research group develops the unique measuring systems for studying the influence of boundary conditions and initial molecular kinetics on the solidification process of polymer melts in which the material structure is being formed.As accompanying tool the software for interconversion of the viscoelastic material functions and determination of the mechanical spectrum (utilizing the iterative numerical algorithm 'Emri-Tschoegel') was developed. The spectrum is qualitatively connected to the molecular weight distribution, which defines the initial kinetics of the material.
The nonlinear model 'Knauss-Emri', developed apparatuses, and accompanying software, represent a unique iterative experimental-analytical tool for studying and analyzing the relations between the chemical structure and the macroscopic behavior of the material in solid state. This new approach enables optimization of processing conditions as well as development of new materials by modifying the initial kinetics of molecules. Based on this approach, the group in collaboration with the German company BASF developed a new generation of thermoplastic polymeric materials (I-Polymers), which were patented in 156 countries and independently with 5 patents in USA and EU.
The goal of this program is to study the effect of thermo-mechanical boundary conditions (i.e.technology) on the polymer structure formation, which results from the nonlinear molecular interactions that take place at different time-space scales. The research is performed at three levels, representing transition from the laboratory to the industrial environment: a) Laboratory scale: study of the influence of controlled boundary conditions on complex material structure formation. This is achieved through precise specimen preparation procedure, which enables very exact control of temperature and pressure history (loading); b) Semi-industrial scale: simulation of controlled boundary conditions by using laboratory extruders and injection molding machines. This is the first step in determination of technological parameters, which lead to the formation of superstructure at real polymer processing conditions; c) Industrial scale: scale-up of the polymer processing technology to the industrial level.
For studying the effect of boundary conditions on the solidification process of polymer melts, the newly developed iterative experimental-analytical approach is used. The interrelation between the variation of boundary conditions and the time-scale of molecular interactions is predicted with the modified 'Knauss-Emri' model. The predicted boundary conditions are used for the specimen preparation. Their structure is then analyzed by different characterization techniques such as creep and relaxation, NMR, DSC, optical and electron microscopy, etc., which allow 'observation of the structure' on different time-space scales. The analytical prediction of boundary conditions is only approximative. The optimization of technological parameters, which induce the formation of superstructure exhibiting the intelligent behavior, should be therefore obtained experimentally through the iterative analysis in the vicinity of the analytical prediction. Small variations in boundary conditions can have significant effect on the struct...
Significance for science
The ultimate goal of the program Intelligent polymeric materials and technologies was to develop the fundamental knowledge and skills needed for generating innovative ideas that represent technological potential and economic opportunities for Slovenia. Two outstanding follow-up results should be emphasized in addition to the planned results: • Novel vibroacoustic damping elements protected by two EU patents. • Closed form algorithm for the time-temperature superposition, which was accepted as a new ISO standard. The research was focused on developing new generation intelligent polymeric materials and technologies. Activities were divided into 3 research spheres: 1. Study of material structure formation process at different observation scales. Where current results show that non-chemical modifications on molecular scvale lead structures that exhibit improved processability, and better mechanical and damping properties. With these knowledge we have improved feedstock materials used in powder injection moulding and develop new generation vibroacoustic damping elements. Future research in this sphere includes developing of implantable medical devices like solid-state drug delivery system based on electrospun nanofibrous membranes made of biodegradable bio-, and synthetic- polymers, and development of new high pressure injection moulding technology. 2. Development of measurement techniques and equipment to characterize time-dependent behaviour of polymers and their composites. During the past period our group developed several novel measuring systems for characterization of time-dependent properties of polymers, particularly at high pressures & high rates, which commercially are not available. The apparatuses allow mechanical characterization of polymers in transition from molten to solid state. At present such investigations are not possible. Based on this knowledge further improvement of vibroacoustic damping elements and drug delivery containers are expected. 3. Theoretical and experimental analysis of the behaviour of structural polymers and their composites under extreme thermo-mechanical boundary conditions where conducted in three main directions: a) Investigation of the effect of material inherent structure, expressed with mechanical spectrum, on the long-term behavior of dynamically loaded polymers, which resulted in a new methodology for predicting durability of elastomeric drive belts. Methodology was implemented in the Goodyear Company. b) Development of a new methodology for predicting long term creep and/or relaxation material functions from short constant stress, or strain rate measurements. c) The group also developed a new algorithm for performing time-frequency temperaturepressure superposition to predict long-term behavior of polymers. The new algorithm was was accepted as a new ISO standard.
Significance for the country
The ultimate goal of our research program Intelligent polymeric materials and technologies was to develop fundamental knowledge and skills needed for generating innovative ideas that represent technological potential and economic opportunities for Slovenia. In this respect two outstanding follow-up results should be emphasized: • Developed vibroacoustic elements protected by EU patents. • Developed closed form shifting methodology accepted as a new ISO standard. The ultimate goal of the research program was to implement newly generated knowledge into innovation process that will lead to new innovative solutions and new functionalities and/or improved durability of existing solutions in different areas of implementation. 1. Utilizing knowledge and research results developed within the first research spehere, where we have studied material structure formation process at different observation scales, we have developed and patented new generation vibro-acoustic damping elements. Into this innovation process we included also undergraduate and graduate students. The novel damping elements represent a big leap in ensuring quality of sustainable living in urban environments. At the same time this represents an opportunity for formation of a new spin-off company, which will initially operate within the Institute for Sustainable Innovative Technologies. Generated knowledge will also be used for developing solid-state drug delivery system and medical implants. 2. One of the measuring devices developed within this research sphere will be used for determination of the limit of linear theory of viscoelasticity, which is the key milestone in intensifying the use of polymeric materials for construction purposes. It is planned to implement this knowledge, together with our industrial partners, for development of new generation remotely operated polymeric valves for heating systems. 3. Research from the third sphere will be utilized for development of new generation polymeric gears. In addition, the developed mathematical algorithm for time-frequency-temperature pressure superposition, which became a new ISO standard, will be implemented into a software packages and with the help of ISO offered to the world market.
Audiovisual sources (1)
Most important scientific results
Annual report
2009,
2010,
2011,
2012,
2013,
final report,
complete report on dLib.si
Most important socioeconomically and culturally relevant results
Annual report
2009,
2010,
2011,
2012,
2013,
final report,
complete report on dLib.si
