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Winnipeg, Canada

Deyholos M.K.,University of Alberta | Potter S.,Composites Innovation Center
Biocatalysis and Agricultural Biotechnology | Year: 2014

Bast fibers (i.e. the phloem fibers of crops such as flax and hemp) have been used for millennia in textiles and cordage and are now promising feedstocks for the production of strong, light weight, renewable composite materials. Several factors limit the broad commercial application of bast fibers in composites, including: (i) variability of fiber properties, (ii) their poor adhesion with conventional resins, (iii) moisture absorption by natural fibers and (iv) cost of production, especially as this relates to extraction of high-quality fibers. These problems will be discussed in the context of fiber developmental biology and of potential solutions enabled by genomics and biotechnology. © 2013 Elsevier Ltd.

Foulk J.A.,U.S. Department of Agriculture | Fuqua M.A.,North Dakota State University | Ulven C.A.,North Dakota State University | Alcock M.M.,Composites Innovation Center
International Journal of Sustainable Engineering | Year: 2010

Flax fibre holds the potential to serve as an alternative to glass fibre as reinforcement in composite applications. To fully achieve this, the interaction between fibre and matrix must be improved and more consistently controlled. Only then will industry accept natural fibres as a sustainable engineering material choice. Traditionally, interfacial strength improvement has been accomplished through expensive and time consuming chemical surface modification(s). To achieve improved market potential and viability, new methods of developing composite ready flax fibre must be researched and developed through an assessment of the impact of fibre traits for unmodified fibre. Metal, fungal, bacterial, wax and glucose content were examined in this study to determine their correlative effects upon interfacial adhesion, as were fibre characteristics such as colour, density, fineness, fibreshape thickness, conductivity and pH levels. Composite performance was evaluated using fibre pullout and interfacial shear strength tests. These first attempts at correlating as-received flax fibre traits and resulting flax fibre composite properties contain the initial steps towards identifying key flax fibre characteristics that influence composite performance so that proper growth and fibre processing approaches can be developed.

Guzman L.,University of Manitoba | Chen Y.,University of Manitoba | Potter S.,Composites Innovation Center | Khan M.R.,University of Manitoba
Agricultural Engineering International: CIGR Journal | Year: 2015

Planetary ball mill is a versatile machine which has been used for grinding different types of materials for size reduction and lately for hemp decortication. PFC3D, software employing the discrete element method (DEM), was used to simulate the power and energy requirement of grinding hemp for fibre using a planetary ball mill. The simulation was facilitated through a series of hemp grinding tests using the planetary ball mill to examine the power draw of the mill. The test results identified that grinding speed had a significant effect on the power draw of the mill. The power draw data were used to calibrate the discrete element parameters for different grinding speeds. Using the calibrated parameters, one was able to predict the kinetic energy and friction power loss of the ball mill. The average value of kinetic energy predicted, for grinding speeds of 200 – 500 r/min, ranged between 0.01 and 0.07 J per grinding ball. The prediction showed that frictional power losses dispersed approximately 10% of the total power requirement of the ball mill. Overall, the simulation using PFC3Dimproved understanding about the dynamics of the grinding balls within a planetary ball mill as well as the energy available for transfer in collisions between the grinding balls and hemp material. © 2015, Int. Comm. of Agricultural and Biosystems Engineering. All rights reserved.

Foulk J.A.,U.S. Department of Agriculture | Rho D.,NRC Biotechnology Research Institute | Alcock M.M.,Composites Innovation Center | Ulven C.A.,North Dakota State University | Huo S.,North Dakota State University
Advances in Materials Science and Engineering | Year: 2011

Bethune seed flax was collected from Canada with seed removed using a stripper header and straw pulled and left in field for several weeks. Unretted straw was decorticated providing a coarse fiber bundle feedstock for enzyme treatments. Enzyme treatments using a bacterial pectinolytic enzyme with lyase activity were conducted in lab-scale reactors. Four fiber specimens were created: no retting, minimal retting, moderate retting, and full retting. Fiber characterization tests: strength, elongation, diameter, metal content, wax content, and pH were conducted with significant differences between fibers. Thermosetting vinyl ester resin was used to produce composite panels via vacuum-assisted infusion. Composite performance was evaluated using fiber bundle pull-out, tensile, impact, and interlaminar shear tests. Composite tests indicate that composite panels are largely unchanged among fiber samples. Variation in composite performance might not be realized due to poor interfacial bonding being of larger impact than the more subtle changes incurred by the enzyme treatment. Copyright © 2011 Jonn A. Foulk et al.

Zhang Y.,NRC Institute for Aerospace Research | Genest M.,NRC Institute for Aerospace Research | Backman D.,NRC Institute for Aerospace Research | Johnston A.,NRC Institute for Aerospace Research | And 2 more authors.
2nd Joint US-Canada Conference on Composites - American Society for Composites, 26th Annual Technical Conference: Canadian Association for Composite Structures and Materials | Year: 2011

The low-speed impact and the compression after impact properties of a carbon fibre/epoxy composite material were investigated using several advanced non-destructive evaluation techniques and experimental mechanics methods. The impact damage measurements, and the residual compressive strength after impact and after cyclic loading, are presented and compared with data generated following a different impact condition. The potential application of non-destructive testing techniques to evaluate deformation/damage growth during cyclic loading is also discussed.

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