Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 12/7/2009
Publication Date: 5/2/2010
Citation: Bajwa, D., Bajwa, S., Holt, G.A. 2010. Laboratory to commercial scale - Correlation in the physical properties of biofiber-polymer composites [abstract]. In: Proceedings of the 11th Inernational Conference on Biocomposites: Transition to Green Materials, May 2-4, 2010, Toronto, Canada. p. 24. Interpretive Summary:
Technical Abstract: Bio-fiber polymer composites have been the focus of automotive and building products industries for the last several years. Significant research has been done to improve the processing and performance characteristics of the bio-fiber composite. Most of the initial research is conducted on a small scale in a laboratory environment. Conducting full scale commercial trials can be limited by resources and equipment availibilty. A study was conducted to compare the physical and mechanical properties of bio-fiber polymer composites extruded on a laboratory extruder and a commercial extruder using comparable formulations. Further, a correlation model between laboratory and commercially produced samples was developed for various properties. Bio-fiber composites constituted of virgin/recycled polymer, wood flour, and cotton burrs from gin waste in different ratios. Four different formulations with various substitutions of wood flour, cotton burr fiber, and high density polyethylene (HDPE) were investigated in this research. The physical and mechanical properties tested were water sorption, modulus of elasticity, modulus of rupture, compression strength, fastener withdrawal capacity, coefficient of linear thermal expansion (CLTE), and hardness. The laboratory test samples were extruded by manually mixing small batch sizes (2 lbs.) of material, whereas commercial test samples were prepared using a mechanical mixer and a large batch size (170 lbs). Test results show significant differences in the physical and mechanical properties of the composite material under the two manufacturing regimes. The laboratory samples exhibited lower density and higher water absorption and high thickness swelling. Modulus of elasticity and flexural strength were higher for the commercial samples. The CLTE values of both laboratory and commercially prepared samples were similar. This study clearly demonstrates that significant difference can occur between laboratory and commercially produced materials. The differences can be attributed to several factors such as moisture content of the raw materials, poor blending, lack of shear mixing, compression, screw design, and configuration of the extruder.