ZIPPERLING RESEARCHES
FOR THE FUTURE
Why does Zipperling bother about research?
(and not confine itself to product development?)
We are the only compounding company in the world with a clear commitment to pursuing a strategy of long-term scientific research and hence to playing our part in solving a number of problems of importance for the future.
Environmental aspects, and especially responsible and sparing use of energy and raw materials, have a major role to play here. In order to help our customers with the development of technically advanced and environment-friendly products, we need a more profound knowledge of the interactions that take place between the substances in concentrates and compounds. For this reason, one focus of our research is the interface between the polymer matrix and the disperse phase.
With the help of the literature survey, you can find informative abstracts, diagrams and pictures taken from our publications (and some selected full texts), or you may ask for a reprint of those articles you wish to read completely.
The following is a brief status update on our research work (October 1995), summarising a number of findings that are important for practical applications and for the solution of future problems.
1. INTERFACES
1.1 Structures and properties of multiphase polymer systems
The most important result of our interface research has been our success in explaining the structures in multiphase polymer systems and the mechanisms responsible for the formation of these structures. Multiphase polymer systems include polymer blends (e.g. high-impact systems), --> colour concentrates), carbon-black-filled compounds, PAni blends, coatings etc. These highly complex structures which we have identified as "dissipative" structures (the small picture above shows a detail from our latest computer simulation) are responsible for the properties that interest us, such as "impact strength", "melt viscosity" and "conductivity". In the meantime we have established a theoretical thermodynamic foundation for these nonequilibrium phenomena.
1.2 Polymer blends and colour
concentrates
The new thermodynamic approach has also enabled us to understand the mechanism of impact modification and the rheology of filled systems. The main areas in which we have applied our findings are colour concentrates for technical polymers, copolymers and polymer blends (including the new CARILON, or various high-impact polyamides, polyacetals, PA-ABS blends and Barex), our technical additive concentrates and our "function concentrates".
1.3 "Absolute
dispersion"
Our findings in the field of interfaces help us to achieve better - in some cases "absolute" - dispersion of pigments. This makes for substantially improved properties in mouldings and permits melt-colouring of fibres.
2. PLASTICS FOR ENVIRONMENTAL PROTECTION
2.1 Cathodic corrosion protection
On the basis of our electrolytically stable electrode compound for masonry drying and desalination, which has been in successful use for some years now, we have developed in cooperation with our licensee a new anodically stable electrode designed for use in cathodic corrosion protection of reinforced concrete and steel structures embedded in the subsoil. Tests at the Federal Materials Testing Establishment in Berlin have yielded positive results.
2.2 Zinc-bromine
battery
We see even greater environmental protection potential in the possibility of using the zinc-bromine plastic battery to power electric vehicles, thereby permitting clean and energy-saving cars and buses. Our research has contributed the electrode for this development
2.3 PET
anti-blocking concentrates
Today polyesters are among the most environment-friendly of materials. Polyester films can only be produced with the aid of anti-blocking agents - a technique we mastered many years ago and have now optimised with new research findings.
2.4 Function concentrates for recycling
Recycling only makes sense if it saves energy and raw materials and yields perfect-quality products for high-grade applications. We develop and produce interface-active concentrates to optimise properties for each individual case.
2.5 Fibre
colouring
"Absolute dispersion" of pigments also permits melt-colouring of fibres, making it possible to save millions of cubic metres of fresh water. Hitherto implemented on a small scale only in Europe, but already a common practice in the USA.
3. ELECTRICALLY
CONDUCTIVE POLYMERS (ICPs): POLYANILINE
3.1 Raw material production
On the basis of the polymerisation process developed by us between 1981 and 1989, a production plant for the manufacture of polyaniline is in operation at Zipperling and a pilot plant in the USA, thereby ensuring for the first time unrestricted worldwide availability of this first "organic metal" for commercial purposes. The basis for this is our advanced dispersion technology which enabled us to reduce the critical volume concentration of polyaniline depending upon the dispersion matrix - down to around 1%.
3.2 Corrosion protection
Our researchers have invented a revolutionary corrosion control system and developed it into marketable products: surface ennoblement and passivation by the redox-active organic noble metal polyaniline. "CORRPASSIV" products are primers for various preventive corrosion control applications, "CORREPAIR" is a set for the home handyman for treating rusty metals. These systems could serve a major environmental protection function - conserving assets whose production involves intensive use of energy and raw materials.
3.3 EMI shielding
On the basis of the ever-improving dispersibility of our new polyaniline we are conducting research into highly conductive PAni-polymer blends that display excellent shielding performance. Our aim is to achieve shielding levels in the region of 40 to 75 dB, depending on frequency, in both near and far fields, with wall thicknesses of 1 - 2 mm. These systems are not yet commercially available.
3.4 Transparent conductive coatings
Another sensational result of our research is a simple process that enables us to apply a coating of polyaniline to substrates of various kinds. This makes it possible to produce transparent antistatic packaging and transport protection for electronic components. Coating systems suitable for the various plastics such as polyolefins on the one hand and PVC, polyesters, polyamides or polyacrylates on the other have been developed for dip and spray applications. Systems for transparent printing are also already in commercial use.
3.5 Conductivity mechanism
For many years it was unclear how intrinsically conductive polymers conduct electricity. Are they genuine metals? Our research in conjunction with the University of Cologne, Germany, and the University of Wellington, New Zealand, has taken us several important steps further forward: ICPs are metals and conduction in them is metallic, but they are subject to a quantum effect.
4. FLAME-PROOFING
4.1 Dioxins in flame-retardant compounds?
Reports of brominated dibenzodioxins and dibenzofurans in flame-retardant plastics have caused disquiet among the public and brought a nervous response from the plastics industry. We have therefore taken part in research work by the German Federal Environmental Agency to throw light on this problem. We offer halogen-containing concentrates with optimum flame-retardant properties that satisfy the most stringent safety and environmental criteria.
4.2 Halogen-free flame-retardant compounds
Quite apart from the dioxin debate, it is a desirable goal to achieve a flame-retardant effect in polymers without the release of corrosive gases. We have a continuous research effort in this field too, and first successes appear to be emerging for certain special applications.
