Flow behaviour and microstructure of a beta-glucan concentrate
Artikel i vetenskaplig tidskrift, 2018

The extensional viscosity is an important rheological characteristic of polymer melts. It is however not as frequently reported on as the shear viscosity. The extensional viscosity is of special interest when considering polymeric materials for foaming and film blowing processes. Here, the extensional (and shear) viscosity along with the melt strength and the tensile properties of the corresponding solid film of a β-glucan concentrate are reported on. A capillary viscometer equipped with a hyperbolic die, yielding a contraction flow, was used to assess the extensional viscosity of the aqueous β-glucan compound at room temperature and at elevated temperatures (110 and 130 °C). In general, the extensional viscosity as well as the shear viscosity decreased with increasing deformation rate. The influence of two different amounts of added water (40 and 50%) was also examined. As expected, both types of viscosities decreased with increasing temperature. It is suggested that gelatinization of the starch fraction in the concentrate at 110 and 130 °C contributes to temperature dependence of the viscosity. To some extent, this is supported by light microscopy and confocal scanning laser microscopy studies of the microstructure of the materials. The results reported here indicate that the β-glucan concentrate might, after some modifications, be used as a complement to fossil-based polymers and processed by conventional manufacturing techniques.

mechanical properties

extensional viscosity





Kristina Karlsson

Chalmers, Industri- och materialvetenskap, Konstruktionsmaterial

Marco Berta

RISE Research Institutes of Sweden

Camilla Öhgren

RISE Research Institutes of Sweden

Mats Stading

Chalmers, Industri- och materialvetenskap, Konstruktionsmaterial

Mikael Rigdahl

Chalmers, Industri- och materialvetenskap, Konstruktionsmaterial

Journal of Polymers and the Environment

1566-2543 (ISSN) 15728919 (eISSN)

Vol. 26 8 3352-3361


Hållbar utveckling


Textil-, gummi- och polymermaterial





Mer information

Senast uppdaterat