Mechanical properties of expanded skin tissue are different from normal skin, which is dependent mainly on the structural and functional integrity of dermal collagen fibrils. In the present study, mechanical properties and surface topography of both expanded and nonexpanded skin collagen fibrils were evaluated. Anisotropic controlled rate self-inflating tissue expanders were placed beneath the skin of sheep's forelimbs. The tissue expanders gradually increased in height and reached equilibrium in 2 weeks. They were left in situ for another 2 weeks before explantation. Expanded and normal skin samples were surgically harvested from the sheep (n = 5). Young's modulus and surface topography of collagen fibrils were measured using an atomic force microscope. A surface topographic scan showed organized hierarchical structural levels: collagen molecules, fibrils and fibers. No significant difference was detected for the D-banding pattern: 63.5 ± 2.6 nm (normal skin) and 63.7 ± 2.7 nm (expanded skin). Fibrils from expanded tissues consisted of loosely packed collagen fibrils and the width of the fibrils was significantly narrower compared to those from normal skin: 153.9 ± 25.3 and 106.7 ± 28.5 nm, respectively. Young's modulus of the collagen fibrils in the expanded and normal skin was not statistically significant: 46.5 ± 19.4 and 35.2 ± 27.0 MPa, respectively. In conclusion, the anisotropic controlled rate self-inflating tissue expander produced a loosely packed collagen network and the fibrils exhibited similar D-banding characteristics as the control group in a sheep model. However, the fibrils from the expanded skin were significantly narrower. The stiffness of the fibrils from the expanded skin was higher but it was not statistically different.

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Silicone rubber biocomposites were prepared with 0%, 4%, 8%, 12%, and 16% bamboo fiber as reinforcement. The compressive set behavior of the samples was compared between the samples that were tested before and after immersion in water. The compression set values for the samples that were immersed in the water were lower than the samples that were not immersed in the water. The moisture absorption rate of the bamboo-silicone biocomposites (BaSiCs) increased as the bamboo fiber content increased. As the bamboo fiber content in the BaSiCs increased, the impact energy and the deflection at peak load values decreased and increased, respectively. The results from this study showed that the addition of bamboo fiber into silicone rubber composites can substantially affect its compressive strength, moisture absorption, and impact strength. This study provided essential knowledge to the development of BaSiCs for cushioning applications, such as shoe insoles.

Deflection of a commercial hollow type fishing rod is investigated in this research. The fishing rod of interest is of Abu Garcia brand, made of carbon fibre. Analytical, experimental and numerical approach were performed to assess the bending of the rod under maximum 1.25 kg load located at the tip which represents the rod in pulling. The deflection is defined by longitudinal displacement of each point of guide rings located along the fishing rod. A mathematical model based on basic bending theory of cantilevered beam is formulated to obtain the deflection and then experiment was carried out by immobilizing one end horizontally on the wall and applying at tip force. The final position of the rings was marked, and the displacements were recorded. Finite element model was developed as an isotropic and elastic material via ANSYS software. Results from all approach were compared and it was found that analytical and numerical able to predict a similar trend of bending behaviour. However, large discrepancies were observed in the experimental curves due to several reasons.

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The moringa oleifera bark (MOB) is well-known for its medicinal properties and various benefits, where combining it with polymers could produce a new superior composite material for medicinal applications. Because this is a novel composite material, even basic information on how the MOB fibres altered the tensile properties of epoxy and silicone rubber is still lacking. Therefore, this study investigated the tensile and deformation behaviour of two newly introduced composite materials, MOB fibre reinforced into epoxy and silicone rubber. ASTM D3039 and ASTM D412 were adapted to prepare the hard and soft composite specimens (0, 4, 8, 12 and 16wt%.), respectively. T-test was conducted to determine the significant difference. The results show that the tensile modulus of MOB-epoxy biocomposite improved from 1240 MPa to 1668 MPa (35% increment) when the fibre content was increased to 16wt%. For MOB–silicone biocomposite, a similar trend was observed where the tensile modulus also increased from 0.076 MPa to 0.12 MPa (64% increment) as the fibre concentration increased from 0 to 16wt%. In conclusion, reinforcing MOB fibre affected the stiffness of silicone rubber more than epoxy; but affected the elongation of epoxy more than silicone rubber. Based on a t-score of 17.5, a significant difference is observed in how reinforcing MOB at various wt% affected the increment of tensile modulus for both hard and soft composites. Finally, the determined tensile modulus compared to other materials could be useful for benchmarking and exploring potential applications.