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Abstracts (International Journals and Books)

[63] I. M. Low, J. Somers, H. S. Kho, I. J. Davies, and B. A. Latella, “Fabrication and properties of recycled cellulose fibre-reinforced epoxy composites”, Composite Interfaces, in press (2008).

Abstract: Epoxy matrix composites reinforced with recycled cellulose fibre (RCF) were fabricated and characterized with respect to their flexural and impact properties. Reinforcement of the epoxy by RCF resulted in a significant increase in the strain at failure, fracture toughness and impact toughness but only a moderate increase in flexural strength and flexural modulus. The effect of accelerated exposure to seawater on the flexural and impact properties was also investigated. The salient toughening mechanisms and crack-tip failure processes were identified and discussed in light of observed microstructures, in particular the orientation of RCF sheets to the applied load.

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[62] A. Mashima, K. Itatani, T. Umeda, I. J. Davies, and S. Koda, “Tensile characteristics of octacalcium-phosphate composite fabricated with alginate”, J. Soc. Inorg. Mater. Jpn., 15(334) pp. 155-163 (2008). 

Abstract: Tensile characteristics of octacalcium-phosphate (Ca₈H₂(PO₄)₆∙5H₂O; OCP) composites fabricated with alginate were examined in this paper. First of all, anisotropically-grown (tape-like) OCP particles were prepared using a homogeneous precipitation method – optimal conditions for the preparation of these tape-like OCP particles with stoichiometric composition were determined to be: (i) pH of the starting solution, 4.0, (ii) concentrations of the starting solutions, 0.0399 mol∙dm^-3 Ca(NO₃)₂, 0.0300 mol∙dm^-3 (NH₄)2HPO₄ and 0.0500 mol∙dm^-3 (NH₂)₂CO and (iii) reflux temperature and time, 70^oC and 24 h, respectively. Typical dimensions of the tape-like OCP particles were 50 x 1 x 0.1 µm³. Following this, thread-like material was fabricated by injecting a paste containing 10 mass% OCP and 7.5 mass% alginate into 1.0 mol∙dm^-3 CaCl₂ solution, with the mechanism behind the gelling process being attributed to flash crosslinking of the alginate with Ca²⁺. Microscopic observation revealed the tape-like OCP particles to be randomly arrayed within the alginate matrix, i.e., an OCP/alginate composite. The tensile strength and elastic modulus of the OCP/alginate composite were 3.1 MPa and 10.4 MPa, respectively; the maximum tensile elongation attained 32.2% (under wet conditions).

[61] J. Sommers, H.S. Kho, R. Al-Ghamedi, I. M. Low, I. J. Davies, and B.A. Latella, “Mechanical and physical properties of recycled cellulose fibre-reinforced epoxy eco-composites”, Adv. Maters. Res., 41-42 pp. 317-322 (2008). 

Abstract: Epoxy composites reinforced with recycled cellulose fibre (RCF) have been synthesized and characterized. The reinforcement by RCF has resulted in a significant increase in the strain at break, fracture toughness and impact toughness but moderate increase in flexural strength and flexural modulus. The effect of seawater soaking on the flexural and impact properties has also been investigated. The micromechanisms of toughening and crack-tip failure processes are identified and discussed in the light of observed microstructures from in-situ and ex-situ fracture.