Could oleaginous flax fibers be used as reinforcement for polymers?

Many works deal with the mechanical properties of flax fibers cultivated for textile applications and today used for the reinforcement of polymers. Nevertheless, quantities of oleaginous flax fiber are obtained each year and not promoted. The aim of this work is to study the mechanical properties of single linseed flax fiber as a function of variety, culture year, dew-retting degree and agronomic factors. Five varieties of oleaginous flax have been characterized by tensile tests on elementary fibers and compared to four varieties of textile flax. These tensile experiments have been carried out on with the same equipment, experimental protocol and environmental conditions. The results show that interesting mechanical properties were obtained with the oleaginous variety and are close of those of textile varieties, such as Agatha or Electra. Considering the diameters and specific properties of these oleaginous fibers, we evidenced that they are good candidates for the substitution of glass fibers in composite materials. To increase the development of flax fibers, it is important to have a better control of the spread of their mechanical properties. This point could be observed with the Everest variety cultivated for 4 years and no conclusion could be made. We have evidenced that the retting degree has no influence on the diameters and mechanical properties of the fibers; the same conclusion is obtained with agronomic factors such as seeding rate and plant height. (C) 2011 Elsevier B.V. All rights reserved.