Four-point bending tests were performed for flexural properties according to ASTM D7264, with the specimen size of 100 mm x 12.7 mm x 2 mm, support span (L) and load span set at 67.2 mm and 33.6 mm respectively. The testing rate (R) of 3.59 mm/min was calculated based on the equation (R = 0.167ZL 2 /d) from the ASTM D6272, where d is the depth (thickness) of the beam (mm) and Z is the straining rate of the outer fibres (0.01 mm/mm min).