scholarly journals The Physical and Mechanical Properties of Corn-based Bioplastic Films with Different Starch and Glycerol Content

2021 ◽  
Vol 32 (3) ◽  
pp. 89-101
Author(s):  
Nur Nadia Nasir ◽  
◽  
Siti Amira Othman ◽  
Keyword(s):  
Mechanical Properties ◽  
Water Absorption ◽  
Absorption Rate ◽  
Corn Starch ◽  
Physical And Mechanical Properties ◽  
High Strength ◽  
Major Drawback ◽  
Water Absorption Rate ◽  
Strength And Stiffness ◽  
Mechanical Tensile

Petroleum-based plastics have had a long history with varied materials and applications. However, the major drawback with these plastics is their harmful impact on the environment. Poor disposal management of these plastics have ultimately affected humans. Therefore, starch-based bioplastics have been widely used because of their renewability, sustainability and cost-effectiveness. This work investigated the effect of different concentrations of corn starch (10%, 15%, and 20% w/w of distilled water) and glycerol (20%, 30%, and 40% w/v of corn starch) on the properties of corn-based bioplastic films. Particularly, mechanical (tensile strength, Young’s modulus and elongation at break) and physical (water absorption rate and moisture content) properties were investigated. These films were prepared by the solvent casting method. It was demonstrated that the addition of 30% glycerol produced mechanical properties closest to the standard value, while films with a composition of 15% of corn starch had the most optimised value. Meanwhile, 20% glycerol and 20% corn starch produced a film with high strength and stiffness but lacked flexibility. Higher concentrations of starch and glycerol produced the highest moisture and water absorption rate. This was due to the highly hydrophilic nature of both corn starch and glycerol. However, the concentration of glycerol needs to be adjusted based on the intended use of the film. In conclusion, the concentration of corn starch and glycerol produced slightly different outcomes. Thus, the properties and application of the cornbased bioplastic films can be maximised by optimising the concentration of corn starch and glycerol.

scholarly journals Physical and mechanical properties of mortars containing date palm fibers

2022 ◽  
Author(s):  
Saleh Bamaga
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Water Absorption ◽  
Absorption Rate ◽  
Date Palm ◽  
Physical And Mechanical Properties ◽  
Water Absorption Rate ◽  
Date Palm Fibers ◽  
Rate Test ◽  
Construction Works

Abstract This paper presents the results of a study conducted to investigate the effects of incorporating Sefri Date Palm Leave Fibers (SDPLF) into the mortar. A total of seven mixtures were prepared and tested. SDPLF were collected from local farms. The fibers were then cleaned, dried, and cut to different sizes of 10 mm, 20 mm, and 50 mm, maintaining the same individual fiber width of approximately 5±2 mm. The content of SDPLF in mortars was kept to 1% and 3% by mass. The physical and mechanical properties of SDPLF fibers and SDPLF mortars were investigated. The compressive strength at 7, 14, and 28 days was determined. The water absorption rate test was carried out on mortars containing 1% SDPLF fibers. The results showed that mortars with SDPLF have lower workability, lower density, and lower compressive strength as compared to control mortars. However, they are still acceptable for use in construction works. Mortars containing 10 mm and 20 mm SDPLF fibers by mass showed significant improvement in terms of water absorption rate as compared to the control mortar.

scholarly journals Thermal Action on Normal and High Strength Cement Mortars

2020 ◽  
Vol 10 (18) ◽  
pp. 6455
Author(s):  
Marianela Ripani ◽  
Hernán Xargay ◽  
Ignacio Iriarte ◽  
Kevin Bernardo ◽  
Antonio Caggiano ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Water Absorption ◽  
Peak Load ◽  
Physical And Mechanical Properties ◽  
Thermal Action ◽  
High Strength ◽  
Strength Loss ◽  
Brittle Behavior ◽  
Cement Mortars ◽  
Water Absorption Test

High temperature effect on cement-based composites, such as concrete or mortars, represents one of the most important damaging process that may drastically affect the mechanical and durability characteristics of structures. In this paper, the results of an experimental campaign on cement mortars submitted to high temperatures are reported and discussed. Particularly, two mixtures (i.e., Normal (MNS) and High Strength Mortar (MHS)) having different water-to-binder ratios were designed and evaluated in order to investigate the incidence of both the mortar composition and the effects of thermal treatments on their physical and mechanical properties. Mortar specimens were thermally treated in an electrical furnace, being submitted to the action of temperatures ranging from 100 to 600 °C. After that and for each mortar quality and considered temperature, including the room temperature case of 20 °C, water absorption was measured by following a capillary water absorption test. Furthermore, uniaxial compression, splitting tensile and three-points bending tests were performed under residual conditions. A comparative analysis of the progressive damage caused by temperature on physical and mechanical properties of the considered mortars types is presented. On one hand, increasing temperatures produced increasing water absorption coefficients, evidencing the effect of thermal damages which may cause an increase in the mortars accessible porosity. However, under these circumstances, the internal porosity structure of lower w/b ratio mixtures results much more thermally-damaged than those of MNS. On the other hand, strengths suffered a progressive degradation due to temperature rises. While at low to medium temperatures, strength loss resulted similar for both mortar types, at higher temperature, MNS presented a relatively greater strength loss than that of MHS. The action of temperature also caused in all cases a decrease of Young’s Modulus and an increase in the strain corresponding to peak load. However, MHS showed a much more brittle behavior in comparison with that of MNS, for all temperature cases. Finally, the obtained results demonstrated that mortar quality cannot be neglected when the action of temperature is considered, being the final material performance dependent on the physical properties which, in turn, mainly depend on the mixture proportioning.

scholarly journals The numerical simulation of Influence of Drying-wetting Cycles on the Deterioration Characteristics of Gypsum Rocks under Particle Flow Code

2020 ◽  
Vol 24 (1) ◽  
pp. 55-59
Author(s):  
Guopeng Wu ◽  
Wenwu Chen ◽  
Kai Cui
Keyword(s):  
Mechanical Properties ◽  
Numerical Simulation ◽  
Water Absorption ◽  
Absorption Rate ◽  
Early Stage ◽  
Particle Flow ◽  
Wetting And Drying ◽  
Water Absorption Rate ◽  
Gypsum Rock ◽  
Deterioration Characteristics

In order to study the influence of dry-wet cycling on the deterioration characteristics of gypsum rocks and solve the problems encountered in engineering construction, in this study, gypsum rocks are taken as the research object. With the combination of laboratory test and theoretical analysis, the numerical simulation of particle flow is carried out, and the deterioration characteristics of physical and mechanical properties of gypsum rock under dry-wet cycling are studied. The results show that gypsum, quartz, zeolite and dolomite are the main components of gypsum rocks. Gypsum occupies the most components in gypsum rocks, so the various characteristics of gypsum greatly affect the characteristics of gypsum rocks. The process of water absorption and loss of gypsum is similar, which shows that the rate of water absorption or loss of gypsum is faster in the early stage, and tends to be stable in the later stage. The curve of the whole process of water absorption and loss is fitted by negative exponential function, and the effect is better. The larger the porosity of gypsum rock is, the better its water absorption performance is. Intergranular pore, dissolution pore and dissolution pore are the main pore types of gypsum rock. Intergranular pore is the main water absorption channel of gypsum rock. The cumulative water absorption increases with the increase of wetting and drying cycles. The change of water absorption curve is mainly manifested in water absorption rate and time. The more the number of wet-dry cycles is, the higher the water absorption rate in the early stage of water absorption is, the closer the characteristic curve to the coordinate axis of water absorption is, and the shorter the water absorption time is. In contrast, the shape difference of water loss curve is very small. It can be seen from this that in the process of wetting and drying cycle, the hydrophysical and hydrochemical processes promote each other, which changes the crystal structure and pore structure of gypsum rocks, reduces the crystal strength and increases the porosity, thus leading to the deterioration of the mechanical properties of gypsum rocks.

Use of polyvinyl chloride (PVC) powder and granules as aggregate replacement in concrete mixtures

2016 ◽  
Vol 23 (2) ◽  
pp. 209-216 ◽  
Author(s):  
Hakan Bolat ◽  
Pınar Erkus
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Water Absorption ◽  
Polyvinyl Chloride ◽  
Physical And Mechanical Properties ◽  
High Strength ◽  
Capillary Water ◽  
Capillary Water Absorption ◽  
Concrete Mixtures ◽  
Compressive Strength Test

AbstractConcrete is one of the materials in which polymer wastes are utilized. Generally, these wastes are added at specific rates in scientific studies but an important problem of waste polymers is size irregularity. Even when consistent dosage rates are used, variations in polymer size can lead to variability in the physical and mechanical properties of the concrete produced. The aim of this study is to determine physical and mechanical properties of polyvinyl chloride (PVC)-containing concretes. In order to produce normal and high strength concretes, 10%, 20%, and 30% replacement ratios of PVC powder and granules by volume of aggregate are used. Slump, fresh and hardened densities, compressive strength, capillary water absorption, and abrasion were tested on all concrete types. As the PVC ratio increases, important changes are seen in all physical and mechanical concrete properties. The unit weights of the 10%, 20%, and 30% replacement PVC powder concretes are lower by ∼4%, 8%, and 13%, respectively, as compared to the reference mixtures, and the replacement PVC granule concretes are lower by ∼2%, 4%, and 7%. Compressive strength test results showed similar trends. As PVC replacement increases, the capillary water absorption decreases between 10% and 50%, and abrasion decreases between 27% and 77%.

Mechanical and Tribological Characterization of Hybrid Natural Fiber Reinforced Composites

2020 ◽  
Vol 12 (2) ◽  
pp. 136-143
Author(s):  
Hiral H. Parikh ◽  
Harshit P. Soni ◽  
Deval A. Suthar ◽  
Dhruv H. Patel
Keyword(s):  
Mechanical Properties ◽  
Water Absorption ◽  
Absorption Rate ◽  
Natural Fiber ◽  
Epoxy Composite ◽  
Natural Fibers ◽  
Synthetic Fiber ◽  
Test Results ◽  
Fiber Reinforced ◽  
Water Absorption Rate

Background: The technological enhancement in various disciplines enhances the demand for the new material which can replace the conventional materials. This has initiated the idea of composite materials. Synthetic fiber reinforced polymer matrix composites are being widely used due to its mechanical properties, but these fibers lack in terms of biodegradability, initial processing cost, recyclability and health hazard. An alternative to tackle these drawbacks can be found in natural fibers, that give an advantage in terms of strength to weight ratio, ease of availability and biodegradability. Methods: This work is aimed to determine the effect of hybrid basalt - banana reinforced epoxy composite and their effectiveness in substituting few conventional materials in terms of their mechanical properties, wear resistance and water absorption rate. Results: Basalt Banana Hybrid Composite (BBHC) is tested for their mechanical strength, hardness, impact strength, flexural strength, wear rate and water absorption rate. The test results of mechanical properties for the BBHC are compared to the other hybrid materials and conventional materials. Conclusion: The test results reveal that the hybrid basalt banana epoxy composite is a good substitute over various conventional materials. The water absorption test results reveal that the hydrophilic nature of the natural fibers reduces a lot after the hybridization.

scholarly journals Effects of Chemical Treatment on Mechanical Properties of Oil Palm Empty Fruit Bunch (EFB) with Urea Formaldehyde (UF) Resin Particleboardtype

2020 ◽  
Vol 8 (5) ◽  
pp. 1330-1334
Keyword(s):  
Mechanical Properties ◽  
Water Absorption ◽  
Oil Palm ◽  
Chemical Treatment ◽  
Absorption Rate ◽  
Urea Formaldehyde ◽  
Bending Test ◽  
Empty Fruit Bunch ◽  
Water Absorption Rate ◽  
Uf Resin

Oil palm plant by-product such empty fruit bunches (EFB) are not effectively utilized and in many instances had caused severe pollution problems. It has a potential to replace the wood in the production of particleboard in furniture industry. This research aim is to investigate the effects of the chemical treatment on the mechanical properties of the oil palm empty fruit bunch (EFB) with urea formaldehyde (UF) resin particleboard through Scanning Electron Microscopy (SEM), flexural test – three point bending test and the water absorption test. A single layered oil palm EFB/UF particleboard with the fibres treated with NaOH of 0.5%, 1.0% and 1.5% concentrations were made. Testing procedure was done in accordance with the American Standard Testing Materials - ASTM 1037 standard for testing wood based fibre and particle panel materials. The SEM images of 1.0% NaOH treated fibre shows a rougher surface indicating that more silica bodies are detached from the EFB surface which improves the mechanical interlocking ability of the fiber. Flexural properties the treated EFB/UF particleboard shows an improved quality compared to the untreated board. There is significant increase of 82% and 81% in the flexural strength and flexural modulus respectively of the 1.0% NaOH treated board from 0.5% NaOH treatment. As for the water absorption rate, the treated particle board shows a decrease in water absorption rate after the treatment.

Effect of Water Absorption on Mechanical Properties of Hemp Fiber Reinforced Composite

2009 ◽  
Vol 417-418 ◽  
pp. 161-164 ◽  
Author(s):  
Kenichi Takemura
Keyword(s):  
Mechanical Properties ◽  
Water Absorption ◽  
Absorption Rate ◽  
Strength Reduction ◽  
Fiber Content ◽  
Hemp Fiber ◽  
Absorption Time ◽  
Dry Process ◽  
Water Absorption Rate ◽  
Effect Of Water

In this study, the effect of water absorption on mechanical properties of hemp fiber reinforced green composite(HGC) was examined. Plain woven hemp fabric was used as reinforcement. Emulsion type biodegradable resin was used as matrix. The composite was made by compression molding method. Water absorption rate and the effect of the ratio on the mechanical properties were examined. Following results are obtained. The water absorption rate increased with an increase of absorption time. The water absorption rate had an equilibrium state within 30 days. The duration was not dependent on fiber content. In the case of that specimen was kept in water 182 days, the strength decreased 70% of the ultimate one. But in the case that the specimen has dry process after water absorption process, the strength recovered 57%. The recovery ratio is not dependent on water absorption time. The strength reduction rate after dry process is not dependent on fiber content. The strength of resin decreased 62%, and the strength of fiber decreased 13% by water absorption. So the strength reduction of the composite is due to the effect of matrix.

scholarly journals Moisture Absorption Behavior and Adhesion Properties of GNP/Epoxy Nanocomposite Adhesives

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1850
Author(s):  
Nurziana Kong ◽  
Nur Zalikha Khalil ◽  
Holger Fricke
Keyword(s):  
Mechanical Properties ◽  
Shear Strength ◽  
Water Absorption ◽  
Water Uptake ◽  
Absorption Rate ◽  
Adhesive Bonding ◽  
Moisture Absorption ◽  
Adhesion Properties ◽  
Water Absorption Rate ◽  
Immersion Period

In the current work, an attempt has been made to investigate the effect of Graphene Nanoplatelets (GNP) reinforcement to water absorption behavior and mechanical properties of adhesive bonding with epoxy. Epoxy adhesive with various GNP content (i.e., 0.0~2.0 wt%) was utilized to joint aluminum adherend subjected to various immersion periods (i.e., 0~60 days). Subsequently, the effect of GNP reinforcement on water uptake, water absorption rate and tensile shear strength was investigated. Depending on GNP content, two distinct behaviors in water uptake and moisture absorption rate have been observed; specimens with lower GNP content (0.5~1.0 wt%) have demonstrated increased/retention of water uptake and water absorption rate regardless of immersion period. Meanwhile, at higher GNP content (1.5~2.0 wt%), decreased water uptake and water absorption rate are generally observed. At similar GNP content, regardless of immersion periods, water immersed specimens generally demonstrate higher or retention of shear strength when compared to specimens at 0-day immersion period. These observations suggest that the relation between moisture absorption behavior and mechanical properties of GNP-reinforced adhesive with GNP content are rather complex which might be attributed to the interplay of several possible mechanisms.

scholarly journals Structural Characterization and Analysis of High-Strength Laminated Composites from Recycled Newspaper and HDPE

Polymers ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1311 ◽  
Author(s):  
Binwei Zheng ◽  
Chuanshuang Hu ◽  
Litao Guan ◽  
Jin Gu ◽  
Huizhang Guo ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Water Absorption ◽  
High Density Polyethylene ◽  
Laminated Composites ◽  
Quantitative Description ◽  
Physical And Mechanical Properties ◽  
High Strength ◽  
Maximum Density ◽  
Pressing Time

Recycled newspaper (NP) shows excellent potential as a reinforcement for polymer composites. Herein, high-strength laminated composites were prepared by using NP laminas as reinforcement and high-density polyethylene (HDPE) films as matrix. Physical and mechanical properties of the laminated composites were measured. It was found that the flexural strength of the composites had a good linear relationship to its density, with R2 = 0.9853. The flexural and tensile strength of the composites at the maximum density (1.40 g/cm3) reached up to 95.6 ± 2.4 MPa and 99.4 ± 0.8 MPa, respectively. SEM results showed that NP layer inside the composite became compact at the hot pressing time of 40 min, because the melted HDPE permeated into the NP layers to bond the NP fibers. Quantitative description of the composite porosity was conducted according to the density of the composite. The 24-h water absorption of the composite was highly related to its porosity, with R2 = 0.8994. This study reveals that density of laminated composites is an important parameter, which could be used to forecast the mechanical strength, and its derived value, porosity of the composites, could be used to predict the water absorption behavior of the composite.

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