Compounding / Extrusion

The Compounding/Extrusion team deals with the development, modification and functionalization of plastics as well as product, tool and process design for the production of extrudates.

Modern machinery and highly qualified specialists form the basis for project-related cooperation with industry for the successful implementation of innovative R&D projects. Our area of expertise ranges from multiphysics simulation to the recycling of post-consumer waste.

Core competencies

  • Material development / compounding
  • Extrusion (multilayer films, profiles, sheets)
  • Process technology, tooling technology
  • Component design, tool design
  • Process development
  • Material testing, plastics analytics
  • Rheology, material data determination
  • Additive manufacturing, 3D printing (Freeformer, FDM / FFF)
  • Material development / filament extrusion for 3D printers
  • Flow simulation of extrusion tools
  • Structural analysis of tools and components


  • Coperion ZSK 26 Mc with co-rotating twin screw
  • screw outer diameter Da = 26mm
  • Da/Di = 1.55
  • process length 44 L/D
  • modular, flexible process section and screw geometry design
  • twin screw side feeder type ZSB 26 incl. Coperion FET
  • twin screw side feeder type ZS-EG 26

Download Anlagenflyer Compoundieranlage

  • Various gravimetric solids feeders
  • Various liquid metering systems (volumetric/gravimetric)
  • Vacuum compacting system
  • SGS 50 strand pelletizing system
  • Maag extrex EX 32-6 GU melt pump
  • ECON ESK 40 Continuous two-piston screen changer
  • ECON EWA 50 underwater pelletizer
  • ECON EWA 50 air pelletizing
  • Mini-micro pelletizing possible


  • 3 extruder 25L/D Ø 30mm
  • 1 extruder 30L/D Ø 30mm
  • 1 extruder 30L/D Ø 30mm, HT up to 450°C
  • 1 extruder 30L/D Ø 20mm, HT up to 500°C
  • Gravimetric metering on all extruders
  • Various screw geometries
  • Maximum output per extruder approx. 15kg/h
3-layer flat film line
  • Wide slot die 400mm with 3-layer feedblock, gap range 0.4 - 5mm
  • Wide slot die 150mm mono or 2-layer, gap range 0.1 - 2mm
  • COLLIN CR 136/450 S flat film line
  • Roll temperature range 25 - 150°C
  • Extrusion in 0° or 90° configuration
  • Edge trim
  • Unwinder for feeding films

Download Anlagenflyer 3-Schicht-Flachfolienanlage

5-layer blown film line
  • Stacking die with radial spiral distributor
  • Blast tower height adjustable (3.4m to 4.2m) with turner bar system
  • throughput range 10-30kg/h
  • Nozzle diameter Ø 60mm
  • Maximum film dispensing width 300mm
  • Film thickness 30μm - 150μm

Download Anlagenflyer Blasfolienextrusion

Multilayer profile and pipe line
  • Modular line design with up to 6 extruders
  • Various own extrusion dies
  • Calibration table with two vacuum pumps
  • Vacuum tank, wet and dry calibration
FDM filament line
  • Customized material development
  • Extrusion dies for Ø1.75 and Ø2.85mm
  • Heatable, multifunctional water bath
  • haul-off and winder


Mold, process and component simulation
  • CFD Simulation: ANSYS CFX, ANSYS Fluent, ANSYS Polyflow
  • FEM Simulation: ANSYS Mechanical, Marc Mentat
  • Process simulation: ANSYS Polyflow, chillWARE
  • Thermal coupled tool simulation
  • Fluid-structure coupling
  • Multiphase flow simulation
  • Simulation at tool exit
  • Simulation of forming processes
  • Simulation of cooling processes
OceanTide - Recycling plastic waste from the sea

IWK has developed a process for recycling plastic waste from the sea for Princess Cruises in collaboration with Basel-based start-up Tide Ocean SA.

From 1:27 in the video

FREITAG Circ Case F385

Swiss Plastics Expo Sustainability Award 2023

Tide Ocean

eMove360° Europe – MATERIALICA best of Award 2019
Swiss Plastics Expo Sustainabilty Award 2020

Jansen hipress

European Geothermal Award 2019
German Innovation Award Gold 2019


eMove360° Europe – MATERIALICA Gold Award 2017
German Innovation Award Winner 2018
German Design Award Special Mention 2019

Reference books

Schwendemann, D., In: Oksman K., Mathew A.P., Bismarck A., Rojas O., Sain M. (Hg.): Materials and Energy - Vol.5: Handbook of Green Materials (Chapter 11). World Scientific Publishing Co. Pte. Ltd., 2014. ISBN 978-981-4566-45-2(set). ISBN 978-981-4566-51-3

Schwendemann, D., In: Bledzki, Andrzej K., Sperber, Volker E. (Hg.): Biobased materials - 9th WPC, Natural Fibre and other innovative Composites Congress and Exhibition, Injection Moulding of Biopolymers (Chapter A16). Carl Hanser Verlag, München, Deutschalnd. 2012.-ISBN 978-3-446-43295-6

Schwendemann, D., In: Oksman-Niska, Kristiina; Sain, Mohini (Hg.): Wood-polymer composites. Chapter 4 Manufacturing technologies for wood-polymer compoistes. Woodhead Publishing Limited, Cambridge, England, 2008.-ISBN 978-1-84569-272-8

Schwendemann, D., In: VDI Gesellschaft Kunststofftechnik (Hg.): Aufbereitungstechnik 2008: Von Naturfasern bis Nanoadditiven; Hochleistungsfüllstoffe in der Kunststofftechnik. Aufbereitung von Holz-Kunststoff Kompositen Von der Terrassendiele zum Strukturbauteil (S. 65-78). VDI, Düsseldorf, 2008.-ISBN 978-3182-3429-77

Schwendemann, D., In: Bledzki, Andrzej K.; Sperber, Volker E. (Hg.): 7th Global WPC and Natural Fibre Composites Congress and Exhibition. Compounding of Renewable Materials (Chapter A4). PPH ZAPOL, Szczecin, Polen, 2008.-ISBN 978-83-751809-7-8

Schwendemann, D., In: Bledzki, Andrzej; Sperber, Volker (Hg.): 6th Global Wood and Natural Fibre Composites Symposium. Needs for the Compounding Process to obtain a high performance wood plastic composite (Chapter A7). PPH ZAPOL, Szczecin, Polen, 2006.-ISBN 978-83-60140-87-1



Synergy of recycling technologies for a circular plastics industry
Schwendemann, D., Innovation News Network, 05/2024

Download Papier in der Kunststoffverarbeitung
Schwendemann, D., Keller, L., Grimm, S., Bürgisser, B., Konrad, J., KunststoffXtra 03-04/2024, p. 18-19


Download Ganzheitliche Betrachtung des Produktlebenszyklus
Schwendemann, D., Rickenbacher, S., KunststoffXtra 11-12/2022, p. 25-27

Download 3D printing toughens up
Smith, C., Compounding World 05-2022, p. 57-65

Download Digitalisierung beim Compoundieren
Schwendemann, D., Hollender, J., Ehrig, F., Wick, C., Hänggi, R., Kunststoffe 03-2022, p. 12-15

Download Digitalization in Compounding
Schwendemann, D., Hollender, J., Ehrig, F., Wick, C., Hänggi, R., Kunststoffe 02-2022, p. 6-9

Download IWK setzt Massstäbe - auch international
Schwendemann, D., Rickenbacher, S., KunststoffXtra 01-02/2022, p. 20-21


Download Orientation of Polylactic Acid–Chitin Nanocomposite Films via Combined Calendering and Uniaxial Drawing: Effect on Structure, Mechanical, and Thermal Properties
Singh, S., Kumar Patel, M., Shiyu, G., Teleman, A., Herrera, N., Schwendemann, D., Maspoch, M.L., Oksman, K., nanomaterials 12/2021

Download Sind technische Daten herstellungsunabhängig?
Schwendemann, D., Gmür, M., KunststoffXtra 10/2021, p. 39-41

Download Functional Nanocomposite Films of Poly(Lactic Acid) with Well-Dispersed Chitin Nanocrystals Achieved Using a Dispersing Agent and Liquid-Assisted Extrusion Process
Patel, M.¹, Schwendenmann, D., Spigno, G.³, Geng, S.¹, Berglund, L.¹, Oksman, K.¹,⁴: Functional Nanocomposite Films of Poly(Lactic Acid) with Well-Dispersed Chitin Nanocrystals Achieved Using a Dispersing Agent and Liquid Assisted Extrusion Process
Received: 27 May 2021, Accepted: 23 July 2021, Published: 28 July 2021

Download Co-Extrusion neu gedacht
Biedermann, M.¹, Meboldt, M.¹, Walker, S.², Schwendemann, D.² (¹ETH Zürich (pd|z), ²OST - Ostschweizer Fachhochschule, IWK): Co-Extrusion neu gedacht, Kunststoffe 2/2021, p. 33-36


Download 3D-Druck mit schweizer Premium-Schokolade
Schwendemann, D., Fässler, P.: 3D-Druck mit schweizer Premium-Schokolade, xt Additive Fertigung 4/November 2020, p. 46-49

Download Innovation in der Profil Co-Extrusion
KunststoffXtra 11/2020, p. 18-20

Download Flury, M.: Dem Abfall einen Wert geben, Tide Ocean Material – ein Fair-Trade-Label
KunststoffXtra 7-8/2020, p. 26-27

Download Nachschrumpf reduziert, Produktion gesteigert
Silvan Walker ¹, Prof. Daniel Schwendemann ¹, Prof. Dr. Olaf Tietje ², Beat Schmucki ³ (¹ IWK an der HSR Rapperswil, ² HSR Hochschule für Technik, Rapperswil, ³ Datwyler Cabling Solutions AG, Altdorf): Nachschrumpf reduziert, Produktion gesteigert, KunststoffXtra 5/2020, p. 12-14

Download Effect of Chitin Nanocrystals on Crystallization and Properties of Poly(lactic acid)-Based Nanocomposites
Shikha Singh1,2, Mitul Patel1, Daniel Schwendemann1,3, Marta Zaccone4, Shiyu Geng1, Maria Lluisa Maspoch2, and Kristiina Oksman1,5*
Received: 2 March 2020; Accepted: 16 March 2020; Published: 24 March 2020


Download Im Spannungsfeld der Kreislaufwirtschaft
Schwendemann, D.: Im Spannungsfeld der Kreislaufwirtschaft, KunststoffXtra 12/2019, p. 2-4

Download Von der Skipiste in den 3D-Drucker
Schwendemann, D.: Von der Skipiste in den 3D-Drucker, Additive Fertigung 2/Mai 2019, p. 52-55

Download Simulationsgestützte Werkzeugauslegung
Schwendemann, D., Walker, S.: Simulationsgestützte Werkzeugauslegung, KunststoffXtra 4/2019, p. 24-25


Download die stärkste Kunststofferdwärmesonde der Welt
Schwendemann, D., Alge, D.: Die stärkste Kunststofferdwärmesonde der Welt, KunststoffXtra 11/2018, p. 12-13



Schwendemann, D.: Industry Case Study, European Business Analysis Day, Frankfurt, March 23 2023
Link to the Website


Schwendemann, D.: Wie aus Ozeanplastik nachhaltige Produkte werden / Aus Meeresmüll werden Teile für die Uhrenindustrie, SwissPlastics Expo Award 2020, Luzern, 22. Januar 2020
Link zum Vortrags-Video


Schwendemann, D.: Aus Skischuhen wird Material für den 3D Druck, Swiss Materials, ARGO Chur, 31. Oktober 2019

Schwendemann, D.1,2*, Oksman, K.3, Wick, B.4, Ramsauer, A.5 (Institute of Material Technology and Plastics Processing, University of Applied Sciences Eastern Switzerland, 2 Division of Material Science, Luleå University of Technology, Luleå, Sweden, 3 Division of Material Science, Luleå University of Technology, Luleå, Sweden, 4 SwissPrimePack AG, Altstaetten, Switzerland, 5 Institute of Material Technology and Plastics Processing, University of Applied Sciences Eastern Switzerland): Water-Assisted Compounding of coffee grounds for thermoforming cups, Twenty-second international conference on Composite Materials (ICCM22), Melbourne, Australia, 11-16 August 2019

Schwendemann, D.: Development of water soluble support material for additive manufacturing, 26th BEPS @ Clemson University, Greenville, 6 June 2019

Schwendemann, D.: Zukunftsthemen und Spannungsfelder in der Kunststoffindustrie, Busch Kunststofftage, Maulburg, 5.-6.02.2019


Schwendemann, D.: Compounding of water soluble support material for additive manufacturing, Coperion Extrusion Days 2018, Stuttgart, 28. November 2018