Polymer Synthesis

Process development for polymer dispersions

The Fraunhofer Institute for Applied Polymer Research IAP and PDW Analytics GmbH in Potsdam-Golm have collectively extended the possibilities for particle detection and process development. This has resulted in a globally unique process analysis platform in which particles between 50 nm and
2 mm can be directly detected inline and on a continuous basis at high concentrations.


Highlights:

  • Continuous inline process monitoring
  • Detection of particles from 50 nm to 2 mm
  • No sample taking necessary
  • Undistorted particle size distribution
  • Measuring methods that don’t require calibration

 

Potential:

  • Tracking and understanding the course of the polymerization
  • Increased process reliability
  • Efficient process designs
  • Recognizing and understanding coagulation phenomena
  • Development of feedback strategies
  • Challenge

    Polymer dispersions represent a large proportion of the global polymer market. They are used either directly, for instance as coatings or adhesives, or are intermediate products in the plastics industry, for example in PVC or ABS.

    The particle size distribution of polymer dispersions is a crucial performance characteristic in regard to their application. Established measuring methods provide reliable results only when the dispersions are heavily diluted. This means it is always necessary to take samples. However, particle and droplet systems often react extremely sensitively to changes in the system – particularly during the polymerization reaction. Therefore, the offline measurement of diluted samples is frequently not representative of the actual state of the reaction. Furthermore, time delays, until analysis results become available, are counter-productive for the development of optimum process control.

    Industrial practice is, therefore, dependent on long-term experience and trial and error approaches when it comes to optimizing processes. The resulting process frequently does not achieve its optimum efficiency in terms of product properties and production costs. This is particularly critical in the case of new developments that need to enter the market quickly.

  • Hardware meets know-how

    PDW Analytics GmbH in Potsdam has developed a method of inline measurement of particle sizes between 50 nm and 500 μm that uses photon density wave spectroscopy. This innovative technology was integrated into the process development station at the Fraunhofer IAP. The latter is based on an automated reaction calorimeter RC1e which regulates reaction conditions and records essential parameters, such as reactor and jacket temperature, heat flow, metered flows, pH value and dispersion viscosity.

    Other inline sensors are installed alongside the PDW sensor, which simultaneously determine chemical changes in the system and provide additional measurement values in terms of the size distribution and shape of larger particles over 1 μm. This enables major process steps, such as the emulsification of the monomers, particle formation and colloidal stability to be tracked during the actual process so that a basic understanding of the processes taking place can be developed.

    All of the data obtained from the inline analysis can simultaneously be used to control the process. The unique technical equipment, combined with the know-how of the Fraunhofer IAP in the area of polymer processes, enables a more effective process design and the development of feedback strategies.

  • Applications

    Inks and coatings

    Adhesives
    e. g. for packaging, wood adhesion, binder for cement

    Paper and cardboard
    e. g. laminates, moisture resistance, adhesion

    Textiles and nonwovens
    e. g. for coatings: protective clothing (fi re brigade), rainwear, car seat covers, underside of carpeting

    Leather refining

    Printing inks
    e. g. flexographic printing inks for printing on packaging

    Immunoassays

    The platform can also be used in the areas of cosmetics, the food industry and biotechnology
    e. g. creams, lotions, PIT emulsions, juices, milk, fermentation processes, algae cultivation, wet grinding

  • We offer you ...

    • A complete range of R&D services for polymer dispersions
    • Investigation and improvement of synthesis processes in terms of their ability to achieve product properties, robustness and efficiency
    • Improvement of uncertain sub-steps within an existing process
    • The development of completely new heterophase processes and process steps
    • A determination of critical process parameters and parameter windows /safety considerations
    • The customer-specific development of polymerization processes on a lab to mini-plant scale
    • Inline measurements in the course of scaling up / on-site implementation of in situ measuring technology

     

    Potential aspects

    • Monitoring of particle size distribution
    • Optimization of polymer composition and structure
    • Achievement of specific particle morphologies
    • A selection of suitable surfactant mixtures
    • Synthesis of hybrid materials