Quantifying the Tensile Properties of Hevea brasiliensis – Silicone Biocomposite using Neo – Hookean Model

Incorporation of natural fibers into composites have been continuously researched in moving towards a greener environment. As environmental issues such as climate change and global warming is becoming severe, green technology is one of the ways to reduce it. Hevea brasiliensis or commonly called rubber tree produced a lot of sawdust during the conversion of the raw material into product. The sawdust is known as an agricultural waste which has no economic value. Therefore, this study for the first time attempts to utilize the Hevea brasiliensis sawdust by incorporating it with silicone rubber in the making of a new biocomposite material. The samples were prepared in two weight compositions, 0 wt% and 16 wt% in accordance to ASTM D412. Tensile properties of biocomposite was then determined using 3382 Universal Testing Machine 100kN (Instron, U.S.A., 2008). Neo Hookean hyperelastic model was employed where the material constant, C1 values were obtained. The graph plotted shows that the hyperelastic model used can mimic the deformation behavior of silicone biocomposites. The material constants are observed to increase as Hevea brasiliensis fiber are introduced into it. Hence, it can be concluded that pure silicone rubber has higher tensile strength compared to 16 wt% hevea brasiliensis – silicone biocomposite and the addition of fiber increase the stiffness properties of material produced.

Download Full-text

Advances in Natural Rubber Production

Rubber Chemistry and Technology ◽

10.5254/1.3538690 ◽

1994 ◽

Vol 67 (3) ◽

pp. 537-548 ◽

Cited By ~ 11

Author(s):

Abdul Aziz S. A. Kadir

Keyword(s):

Natural Rubber ◽

Hevea Brasiliensis ◽

Management Practices ◽

Rubber Tree ◽

Value Added ◽

Raw Material ◽

High Yield ◽

Processing Efficiency ◽

Tropical Timber ◽

Increasing Demand

Abstract This paper will attempt to highlight the various advances made to date in the production and processing of natural rubber (NR). The commercially planted rubber tree, Hevea brasiliensis, can yield as high as 3,000 kg of rubber per hectare in contrast to the 500 kg rubber per hectare obtained from the wild Amazonian rubber trees. The high yield of commercial rubber trees is attributed to the successful breeding program, efficient development of agronomic and crop management practices and proper exploitation systems. Today, the Hevea brasiliensis trees not only contribute to the supply of world natural rubber, but also to the ever increasing demand of tropical timber. Latex extracted from the rubber tree is processed to meet the specific requirements of the consumers. In the area of processing, emphasis is on the production of NR as an industrial raw material with improved quality and consistency. Efforts are also placed on processing efficiency, optimum product mix and production of value added modified NR such as epoxidized and deproteinized NR. The processing activities also take into consideration the control of processing effluent with appropriate effluent treatments or conversion of effluent to useful materials.

Download Full-text

The Effect of Catalysts Addition to Silicone Rubber as Pressure Transmitting Medium in the Pebble Fuel Production Process

Journal of Physics Conference Series ◽

10.1088/1742-6596/2048/1/012017 ◽

2021 ◽

Vol 2048 (1) ◽

pp. 012017

Author(s):

D Sutarya ◽

I R Pamungkas ◽

H Sukma ◽

DS A Sartono

Keyword(s):

Finite Element ◽

Silicone Rubber ◽

Material Constant ◽

Initial Study ◽

Fuel Production ◽

Element Analysis ◽

Pressing Method ◽

The Finite Element Analysis ◽

Hyperelastic Model ◽

Emitting Media

Abstract Pebble Fuel is a spherical fuel for high temperature gas-cooled reactors (HTGR). This fuel must have a homogeneous density distribution. Hyperelastic material is used as a pressure transmitting medium (PTM) material in making Pebble fuel using the cold quasi-isostatic pressing method. PTM material properties and characteristics were predicted using the finite element analysis method. The problem is the type of material used and its suitable composition to make a pressure-transmitting medium that has the properties and characteristics of the material as predicted. This research discusses the manufacture of tensile specimens for pressure-emitting media using RTV-586 silicone rubber. The composition comprises three different variants with two major ingredients, namely RTV-586 silicone rubber and catalyst. The test results are then analyzed using the finite element method to determine the material composition that is appropriate or close to the predicted properties and characteristics of the PTM material. This initial study used the Mooney-Rivlin hyperelastic model. The Mooney-Rivlin model shows good similarity to the test result data. In future studies, it will make comparisons with other hyperelastic models to get a suitable PTM material constant.

Download Full-text

HbCOI1 perceives jasmonate to trigger signal transduction in Hevea brasiliensis

Tree Physiology ◽

10.1093/treephys/tpaa124 ◽

2020 ◽

Author(s):

Juan Chen ◽

Haitao Yang ◽

Sui Ma ◽

Ruifeng Yao ◽

Xi Huang ◽

...

Keyword(s):

Signal Transduction ◽

Hevea Brasiliensis ◽

Woody Plants ◽

Essential Role ◽

Molecular Mechanisms ◽

Rubber Tree ◽

Raw Material ◽

The World ◽

Coronatine Insensitive 1 ◽

Latex Biosynthesis

Abstract Natural rubber, a strategically essential raw material used in manufacturing throughout the world, is produced from coagulated and refined latex of rubber tree (Hevea brasiliensis). It is known that phytohormone jasmonate (JA) plays an essential role in regulating latex biosynthesis. However, it is unclear how the JA signal is sensed in a rubber tree. Here, we showed that Hevea brasiliensis CORONATINE-INSENSITIVE 1 (HbCOI1) acts as a receptor that perceives JA to recruit HbJAZ1 for signal transduction. We found that HbCOI1 restores male sterility and JA responses of the coi1–1 mutant in Arabidopsis. The identification of a JA receptor in the rubber tree is essential for elucidating the molecular mechanisms underlying JA-regulated latex biosynthesis. Our results elucidate the mechanism of JA perception in Hevea brasiliensis and also provide an efficient strategy to identify JA receptors in woody plants.

Download Full-text

Influence of fire on ambrosia beetles (Curculionidae, Scolytinae and Platypodinae) in rubber tree plantations (Hevea brasiliensis) in southern Brazil

10.1603/ice.2016.112050 ◽

2016 ◽

Author(s):

Gabriela Costa Pinheiro

Keyword(s):

Hevea Brasiliensis ◽

Rubber Tree ◽

Tree Plantations ◽

Southern Brazil ◽

Ambrosia Beetles

Download Full-text

Co- and post-translational processing of the hevein preproprotein of latex of the rubber tree (Hevea brasiliensis)

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)98499-1 ◽

1991 ◽

Vol 266 (24) ◽

pp. 15944-15948

Author(s):

H.I. Lee ◽

W.F. Broekaert ◽

N.V. Raikhel ◽

H. Lee

Keyword(s):

Hevea Brasiliensis ◽

Rubber Tree

Download Full-text

Optimization of a pretreatment and hydrolysis process for the efficient recovery of recycled sugars and unknown compounds from agricultural sweet sorghum bagasse stem pith solid waste

PeerJ ◽

10.7717/peerj.6186 ◽

2019 ◽

Vol 6 ◽

pp. e6186 ◽

Cited By ~ 2

Author(s):

Ting-Ting Jiang ◽

Yan Liang ◽

Xiang Zhou ◽

Zi-Wei Shi ◽

Zhi-Jun Xin

Keyword(s):

Solid Waste ◽

Sweet Sorghum ◽

Agricultural Waste ◽

Value Added ◽

Raw Material ◽

Alkali Concentration ◽

Sweet Sorghum Bagasse ◽

Amorphous Cellulose ◽

Sorghum Bagasse ◽

Value Added Products

Background Sweet sorghum bagasse (SSB), comprising both a dermal layer and pith, is a solid waste generated by agricultural activities. Open burning was previously used to treat agricultural solid waste but is harmful to the environment and human health. Recent reports showed that certain techniques can convert this agricultural waste into valuable products. While SSB has been considered an attractive raw material for sugar extraction and the production of value-added products, the pith root in the SSB can be difficult to process. Therefore, it is necessary to pretreat bagasse before conventional hydrolysis. Methods A thorough analysis and comparison of various pretreatment methods were conducted based on physicochemical and microscopic approaches. The responses of agricultural SSB stem pith with different particle sizes to pretreatment temperature, acid and alkali concentration and enzyme dosage were investigated to determine the optimal pretreatment. The integrated methods are beneficial to the utilization of carbohydrate-based and unknown compounds in agricultural solid waste. Results Acid (1.5−4.5%, v/v) and alkali (5−8%, w/v) reagents were used to collect cellulose from different meshes of pith at 25–100 °C. The results showed that the use of 100 mesh pith soaked in 8% (w/v) NaOH solution at 100 °C resulted in 32.47% ± 0.01% solid recovery. Follow-up fermentation with 3% (v/v) acid and 6.5% (w/v) alkali at 50 °C for enzymolysis was performed with the optimal enzyme ratio. An analysis of the surface topography and porosity before and after pretreatment showed that both the pore size of the pith and the amount of exposed cellulose increased as the mesh size increased. Interestingly, various compounds, including 42 compounds previously known to be present and 13 compounds not previously known to be present, were detected in the pretreatment liquid, while 10 types of monosaccharides, including D-glucose, D-xylose and D-arabinose, were found in the enzymatic solution. The total monosaccharide content of the pith was 149.48 ± 0.3 mg/g dry matter. Discussion An integrated technique for obtaining value-added products from sweet sorghum pith is presented in this work. Based on this technique, lignin and hemicellulose were effectively broken down, amorphous cellulose was obtained and all sugars in the sweet sorghum pith were hydrolysed into monosaccharides. A total of 42 compounds previously found in these materials, including alcohol, ester, acid, alkene, aldehyde ketone, alkene, phenolic and benzene ring compounds, were detected in the pretreatment pith. In addition, several compounds that had not been previously observed in these materials were found in the pretreatment solution. These findings will improve the transformation of lignocellulosic biomass into sugar to create a high-value-added coproduct during the integrated process and to maximize the potential utilization of agricultural waste in current biorefinery processing.

Download Full-text

Biosorption of Pb(II) Using Coffee Pulp as a Sustainable Alternative for Wastewater Treatment

Applied Sciences ◽

10.3390/app11136066 ◽

2021 ◽

Vol 11 (13) ◽

pp. 6066

Author(s):

Dora Luz Gómez-Aguilar ◽

Juan Pablo Rodríguez-Miranda ◽

Deisy Baracaldo-Guzmán ◽

Octavio José Salcedo-Parra ◽

Javier Andrés Esteban-Muñoz

Keyword(s):

Wastewater Treatment ◽

Agricultural Waste ◽

Green Technology ◽

Point Of Zero Charge ◽

Cellulose Content ◽

The Sustainable Development ◽

Coffee Pulp ◽

Biosorption Process ◽

Optimum Ph ◽

Development Goals

The present research shows the results obtained from the biosorption process of Pb, using coffee pulp as a biosorbent in synthetic waters. To do this, the lignin and cellulose content and the percentage of removal of Pb2+ ions was determined; additionally, the sorption’s optimal variables, such as the optimum pH, the point of zero charge (pHpzc), the kinetics and the adsorption isotherm, were determined. A comparison was made with other by-products derived from coffee crops. According to the results obtained in this research, the cellulose percentage was 29.12 ± 0.22% and the lignin percentage was 19.25 ± 0.16% in the coffee pulp, the optimum pH was 2.0 units and the kinetic model, which adjusted to the biosorption’s process, was the pseudo-second order of Ho and McKay, presenting an isotherm of Langmuir’s model and pHpzc of 3.95 units. Lastly, the removal of the pollutant was 86.45%, with a capacity of maximum adsorption of 24.10 mg·g−1 obtained with a particle size of 180 µm, time of contact of 105 min and at 100 RPM. Finally, we express that (a) the coffee pulp can be used as a sustainable alternative for the removal of the pollutant mentioned in synthetic and/or industrial wastewater matrices, to meet goals 3.9 and 6.9 of the Sustainable Development Goals of the 2030 agenda, and (b) the novelty of this research is the use of an agricultural waste of easy acquisition as a sorbent, without chemical modification, since it presented a high percentage of efficiency in the removal of Pb2+ ions. In turn, the challenge of this research is implementing this green technology on a pilot, semi-industrial and/or industrial scale in wastewater treatment systems.

Download Full-text

Strength of side-to-side and step-cut repairs in tendon transfers: biomechanical testing of porcine flexor tendons

Journal of Hand Surgery (European Volume) ◽

10.1177/1753193420939068 ◽

2020 ◽

Vol 45 (10) ◽

pp. 1061-1065

Author(s):

Eivind Strandenes ◽

Peter Ellison ◽

Anders O. Mølster ◽

Nils R. Gjerdet ◽

Irene O. Moldestad ◽

...

Keyword(s):

Tensile Properties ◽

Testing Machine ◽

Biomechanical Testing ◽

Maximum Load ◽

Side Group ◽

Tendon Transfers ◽

Flexor Tendons ◽

Active Mobilization ◽

The Difference

The aim of the study was to compare side-to-side with step-cut repairs to determine how much of the width it is possible to remove and still keep the repair strong enough to start active mobilization. Porcine flexor tendons were used to create side-to-side, one-third step-cut and half step-cut repairs. There were 15 repairs in each group. The tensile properties of the constructs were measured in a biomechanical testing machine. All repairs failed by the sutures splitting the tendon longitudinally. The maximum load and stiffness were highest in the side-to-side group. Our findings suggest that the half step-cut repair can withstand the forces exerted during active unrestricted movement of the digits in tendons of this size. The advantage of the step-cut repair is reduced bulkiness and less friction, which might compensate for the difference in strength.

Download Full-text