Transmitted Light Microscope with Heating Stage up to 600 °C

Transmitted light microscopy is a central method when investigating structural changes in thermoplastic and thermosetting polymers and is an even more powerful tool when combined with a heating stage. With this system it is possible to study thin sections or polymer films regarding their melt and crystallization behaviors. The thickness has to lie in a transmission range which usually is between 5 µm and 15 µm. It is possible to visualize e.g. spherulitic structures in semi-crystalline thermoplastic polymers, trans-crystalline phases between fiber and matrix, dispersion of pores or particles as well as heterogeneities of pressed or injection molded parts and much more.

By using the heating stage, crystallization studies of semi-crystalline materials can be performed. Thereby a thin section of a polymer will be melted and cooled at defined cooling rates. The spherulithes that are being created during the crystallization phase, can be studied by using a suitable objective and contrast filter and recorded with an attached camera system.

Since April 2018 the material analytics group at the IVW has a state of the art transmitted light microscope with hot stage up to 600 °C in operation. The microscope model is a DM6 from Leica with a Linkam heating stage. For visualizing the structures there are magnifications between 25 up to 400 times available. With the different contrasting settings such as bright field, polarization, interference contrast and phase contrast it is possible to choose the most suitable setup for each individual research question and most optimal image quality.

With this new system the IVW can tie up its work to its previous and comprehensive works in the field of melt and crystallization behaviors of thermoplastic polymers as well as trans-crystalline phases between fiber and matrix (Figure 1).

For composites, more and more thermoplastic polymers are being used which requires comprehensive knowledge about their melt and crystallization behaviors as well as their composite materials. The processing of multi-layered films can enable an incorporation of very thin layers at specific locations. Such a multi-layered film can be investigated by using a transmitted light microscope regarding its pores and possible contaminations (Figure 2). New polymers, e. g. from renewable resources, can be modified by using various additives. Herewith the crystallization behavior and subsequently the polymers’ mechanical properties can be influenced, which can be studied again with this powerful tool (Figure 3).

We would like to thank the state Rhineland Palatinate for its funding.

Further Information:
Dr. Barbara Güttler
Material Science
Institut für Verbundwerkstoffe GmbH
Erwin-Schrödinger-Str. 58
67663 Kaiserslautern
Telephone: +49 (0) 631/2017 462
E-Mail: barbara.guettler@ivw.uni-kl.de

Hermann Giertzsch
Material Science
Institut für Verbundwerkstoffe GmbH
Erwin-Schrödinger-Str. 58
67663 Kaiserslautern
Telephone: +49 (0) 631/2017 208
E-Mail: hermann.giertzsch@ivw.uni-kl.de