scholarly journals Experimental and Modelling Study of the Effect of Adding Starch-Modified Natural Rubber Hybrid to the Vulcanization of Sorghum Fibers-Filled Natural Rubber

Polymers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3017
Author(s):  
Mochamad Chalid ◽  
Yuli Amalia Husnil ◽  
Santi Puspitasari ◽  
Adi Cifriadi
Keyword(s):  
Natural Rubber ◽  
Hybrid Material ◽  
Natural Fiber ◽  
Natural Fibers ◽  
Rubber Matrix ◽  
Sem Images ◽  
Rubber Blends ◽  
Rubber Compounds ◽  
Different Temperatures ◽  
Torque Analysis

Natural rubber-starch copolymer hybrid obtained from our laboratory was used as an additive for rubber compound. In this work, the effect of adding this hybrid material to vulcanization kinetics of sorghum fibers-filled natural rubber was studied. The rubber compounds were added with hybrid material at various loadings, i.e., zero to two phr and thus cured at three different temperatures, i.e., 130, 140, and 150 °C. The molecular behaviors due to the hybrid addition were investigated by Fourier-Transform Infrared (FTIR) spectroscopy. The rheological phenomena of the rubber compounds were studied by performing torque analysis in moving die rheometer. The obtained data were utilized to develop the thermodynamic modeling. The compatibility of sorghum fibers-natural rubber blends in the presence of starch-modified natural rubber were characterized using Field Emission Scanning Electron Microscope (FE-SEM). FTIR results show noticeable changes in the peak intensity of particular functional groups from rubber and natural fiber as evidence of molecular interaction enhancements between rubber and natural fibers caused by incorporating the starch-modified natural rubber coupling agent to rubber-natural fiber blends. The curing time for these blends was reduced with lower required activation energy. SEM images show no visible gaps in morphology between natural rubber and the filler indicating that the addition of hybrid material to the blends also improves the compatibility between the fibers and the rubber matrix.

Cotton-Epoxy Composites: Development and Mechanical Characterization

2011 ◽  
Vol 471-472 ◽  
pp. 291-296 ◽  
Author(s):  
Piyush P. Gohil ◽  
A.A. Shaikh
Keyword(s):  
Natural Fiber ◽  
Volume Fraction ◽  
Fiber Composite ◽  
Natural Fibers ◽  
High Strength ◽  
Data Availability ◽  
Sem Images ◽  
Feasible Range ◽  
Set Up ◽  
Natural Fiber Composite

Composites are becoming essential part of today’s material because they offer advantages such as low weight, corrosion resistance, high fatigue strength; faster assembly etc. composites are generating curiosity and interest all over the worlds. The attempts can be found in literature for composite materials high strength fiber and also natural fiber like jute, flax and sisal natural fibers provides data but there is need of experimental data availability for unidirectional natural fiber composite with seldom natural fiber like cotton, palm leaf etc., it can provide a feasible range of alternative materials to suitable conventional material. It was decided to carry out the systematic experimental study for the effect of volume fraction of reinforcement on longitudinal strength as well as Modulus of Elasticity (MOE) using developed mould-punch set up and testing aids. The testing is carried out as per ASTM D3039/3039M-08. The comparative assessment of obtained experimental results with literature is also carried out, which forms an important constituent of present work. It is also observed through SEM images and theoretical investigations that interface/interphase plays and important role in natural fiber composite.

scholarly journals Detailed Study on the Mechanical Properties and Activation Energy of Natural Rubber/Chloroprene Rubber Blends during Aging Processes

2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Quang Nguyen Trong ◽  
Hung Dang Viet ◽  
Linh Nguyen Pham Duy ◽  
Chuong Bui ◽  
Duong Duc La
Keyword(s):  
Mechanical Properties ◽  
Natural Rubber ◽  
Dynamic Loading ◽  
Dynamic Properties ◽  
Activation Energies ◽  
Rubber Matrix ◽  
Static Properties ◽  
Rubber Blends ◽  
Aging Conditions ◽  
Mechanical Aging

Selection of a suitable thermal aging process could render desirable mechanical properties of the rubbers or blended rubbers. In this work, the effect of the aging processes on the mechanical properties and activation energies of natural rubbers (NR) and NR/chloroprene rubbers (CR) blends with low CR contents (5–10%) was investigated. Three aging processes including heat aging (at 110°C for 22 hours), mechanical aging (under dynamic loading to 140% strain for 16000 cycles), and complex aging (heat and mechanical aging) were studied. The results revealed that the compatibility of CR in natural rubber matrix had a significant effect on the dynamic properties of the blended rubber and negligible effect on the static properties. The changes in activation energies of the blended rubber during aging processes were calculated using Arrhenius relation. The calculated changes (ΔUc, ΔUd, and ΔUT) in activation energies were consistent with the results of mechanical properties of the blended rubber. Interestingly, the change in activation energies using complex aging conditions (ΔUc) was mostly equal to the total changes in activation energies calculated separately from heat aging (ΔUT) and mechanical aging (ΔUd) conditions. This indicates that, in complex aging conditions, the heat and dynamic loading factors act independently on the properties of the blended rubber.

scholarly journals Microalgal biomass as renewable biofiller in natural rubber compounds

2021 ◽  
Author(s):  
Emanuela Bellinetto ◽  
Riccardo Ciapponi ◽  
Marco Contino ◽  
Claudia Marano ◽  
Stefano Turri
Keyword(s):  
Thermal Analysis ◽  
Carbon Black ◽  
Natural Rubber ◽  
Shear Fracture ◽  
Pure Shear ◽  
Rubber Matrix ◽  
Compression Moulding ◽  
Microalgal Biomass ◽  
Dynamic Mechanical ◽  
Rubber Compounds

AbstractMicroalgal biomasses, consisting of micronized Spirulina Platensis and its low protein fraction, were investigated in this work as possible renewable biofillers in natural rubber compounds, with the aim of replacing the commonly used carbon black. Natural rubber, in some cases blended with 10% of epoxidized natural rubber to improve the matrix-filler affinity, was compounded with 25, 35, 50 and 75 phr of each biomass. Compounds with 25, 35 and 50 phr of carbon black N990 were also prepared as benchmarks. After compounding, vulcanization times were determined by dynamic mechanical analysis. Rubbers were vulcanized by compression moulding and characterized by means of morphological analysis (scanning electron microscopy), thermal analysis (thermogravimetric analysis, dynamic mechanical thermal analysis) and mechanical tests (tensile tests, strain induced crystallization detection by X-ray diffraction, pure shear fracture tests). Microalgal biomass turned out to be homogeneously dispersed in natural rubber matrix and the materials obtained required lower curing times compared to carbon black compounds. It was found that, up to 50 phr, Spirulina has the ability to increase rubber tensile strength and modulus, acting similarly to N990, while decreasing rubber thermal stability and fracture toughness.

Valorization of Vegetal Fibers in Anti-Fissuration Screed Mortar Formulation

2022 ◽  
Author(s):  
Sergio Pons Ribera ◽  
Rabah Hamzaoui ◽  
Johan Colin ◽  
Benitha Vasseur ◽  
Laetitia Bessette ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Mechanical Strength ◽  
Natural Fiber ◽  
Natural Fibers ◽  
Point Of View ◽  
Synthetic Fiber ◽  
Sem Images ◽  
Hemp Fibers ◽  
Synthetic Fibers ◽  
Rigid Fibers

This work, which is part of the FIBRABETON project, aims to anti-fissuration screed formulations proposition based on natural fibers and comparing these formulations to a synthetic fiber-screed formulation. Different natural fiber (hemp, flax, miscanthus and bamboo) with contents rangingfrom 0.4% to 0.8% were tested. The spread (slump), the shrinkage and mechanical strength (flexural and compressive) studies were carried out. SEM images of natural fibers and natural fibers screed formulation were analyzed. Overall, it is found that all natural fibers screed formulations tested, have shown better behaviour than the synthetic fibers screed formulation in point of view workability, shrinkage and mechanical properties. The lowest shrinkage value is found in the case of the H5 (5 mm long hemp fibers) screed formulation. Generally speaking, the mechanical strength values (flexural and compressive) are more or less similar between natural soft fibers (hemp and flax) and rigid fibers (miscanthus and bamboo). Taking in account slump, shrinkage and mechanical behavior, the proposed good compromise in this work is the H5 screed formulation.

Effect of Compounding Ingredients and Crosslink Concentration on Blooming Rate of Natural Rubber Compounds

2015 ◽  
Vol 1134 ◽  
pp. 50-55 ◽  
Author(s):  
Ummu Qani’ah Yasin ◽  
Dzaraini Kamarun ◽  
Che Mohd Som Said ◽  
Azemi Samsuri
Keyword(s):  
Diffusion Process ◽  
Natural Rubber ◽  
Crosslink Density ◽  
Crystalline Material ◽  
Rubber Matrix ◽  
Opposite Trend ◽  
Rubber Compounds ◽  
Rubber Surface ◽  
Different Types ◽  
High Peroxide

Blooming is a diffusion process whereby compounding ingredients dispersed in rubber matrix migrate to the rubber surface and appears as a layer of white crystalline material. Blooming is a typical phenomenon observed in rubber compounds which could lead to problems such as discoloration and poor appearance of products as well as loss of adhesion. Cause of blooming was still unclear and this research was carried out to identify the effect of compounding ingredients and crosslink concentration on blooming rate in natural rubber compounds. In this project 6 natural rubber formulations based on three different types of compounding ingredients at two different concentrations of crosslinker were compounded and tested for their blooming characteristics. Sulphur, wax and dithiocarbamate as the compounding ingredients were mixed with natural rubber in the presence of 1 and 6 phr of peroxide as the vulcanizing agents. The effect of crosslink concentration on blooming rate of the compounded rubber was then determined. The blooming rate was determined by the weight of the blooming material on the rubber surface as a function of time. The blooming rate was found to be affected by the types of compounding ingredients and crosslink density of rubber. Wax with 6 phr of peroxide showed the highest amount of bloom and the highest blooming rate while the dithiocarbamate accelerator with 1 phr peroxide showed the lowest amount of bloom and the lower blooming rate. As expected, all the compounding ingredients showed an increase of crosslink concentration as the loading of peroxide increases. The blooming rate was also found to be affected by the crosslink concentration of rubber. As the crosslink concentration increases, the rate of blooming increases as were shown by wax and dithiocarbamate accelerator. However, sulphur showed the opposite trend whereby the crosslink concentration increases but the blooming rate decrease. This could be due to the high peroxide level retarding the sulphur blooming process.

The Effect of Chitosan Loading on the Properties of Chitosan Filled Epoxidized Natural Rubber Compounds

2011 ◽  
Vol 471-472 ◽  
pp. 851-856 ◽  
Author(s):  
S.M. Shaari ◽  
Hanafi Ismail ◽  
Nadras Othman
Keyword(s):  
Natural Rubber ◽  
Tensile Modulus ◽  
Epoxidized Natural Rubber ◽  
Rubber Matrix ◽  
Curing Time ◽  
Maximum Torque ◽  
Elongation At Break ◽  
Rubber Compounds ◽  
Curing Characteristics ◽  
Roll Mill

The study of chitosan loading onto epoxidized natural rubber compounds were prepared by incorporation of chitosan into epoxidised natural rubber matrix using a two-roll mill. The effects of chitosan loading on the curing characteristics, tensile properties and morphology of the compounds were investigated. Results indicated that slight changes in curing time (t90), and scorch time (tS2) of the compounds with the incorporation of chitosan. An increment is observed in the maximum torque, tensile modulus and durometer hardness of the compounds while tensile strength and elongation at break declines with chitosan loading.

Influence of bis(triethoxysilylpropyl) tetrasulfide amount on the properties of silica-filled epoxidized natural rubber-based composites

2016 ◽  
Vol 23 (4) ◽  
pp. 357-362
Author(s):  
Omar A. Al-Hartomy ◽  
Ahmed A. Al-Ghamdi ◽  
Said A. Farha Al Said ◽  
Nikolay Dishovsky ◽  
Mihail Mihaylov
Keyword(s):  
Natural Rubber ◽  
Dynamic Properties ◽  
Epoxidized Natural Rubber ◽  
Rubber Matrix ◽  
Coupling Agents ◽  
Silane Coupling Agents ◽  
Rubber Composites ◽  
Rubber Compounds ◽  
Curing Characteristics ◽  
Epoxy Groups

AbstractThe aim of the present article is to investigate the influence of the amount of bis(triethoxysilylpropyl) tetrasulfide on the curing characteristics and mechanical and dynamic properties of rubber composites based on epoxidized natural rubber (Epoxyprene 50) filled with 70 phr silica. The obtained results showed that although the interaction between the epoxy groups of epoxidized natural rubber and the silanol groups of silica through hydrogen bonds improves the dispersion of filler in the rubber matrix, the presence of silane coupling agents is necessary to obtain rubber compounds and vulcanizates with good vulcanization characteristics and mechanical and dynamic properties.

scholarly journals Characterization of novel natural fiber from manau rattan (Calamus manan) as a potential reinforcement for polymer-based composites

2021 ◽  
Author(s):  
Linhu Ding ◽  
Xiaoshuai Han ◽  
Huiling Li ◽  
Jingquan Han ◽  
Lihua Cao ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Natural Fiber ◽  
Natural Fibers ◽  
Morphological Properties ◽  
Thermoplastic Composites ◽  
X Ray Diffraction ◽  
Sem Images ◽  
X Ray ◽  
Cellulosic Fibers ◽  
Degradation Temperature

Abstract The study on novel natural fibers in polymer-based composites will help promote the invention of novel reinforcement and expand their possible applications. Herein, novel cellulosic fibers were extracted from the stem of manau rattan (Calamus manan) by mechanical separation. It is the first time to comprehensively analyze and study the chemical, thermal, mechanical and morphological properties of manau rattan fibers by Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Photoelectron Spectroscopy (XPS), X-Ray Diffraction Analysis (XRD), Thermogravimetric Analysis (TGA), single fiber tensile test and Scanning Electron Microscopy (SEM). Component analysis results showed the cellulose, hemicellulose and lignin contents of manau rattan fibers were 42, 20, and 27%, respectively. The surface of the rattan fiber was hydrophilic according to the oxygen/carbon ratio of 0.49. Manau rattan has a high crystalline index of 48.28%, inducing a high maximum degradation temperature of 332.8°C. This reveals that it can be used as a reinforcement for thermoplastic composites whose operating temperature is below 300°C. The average tensile strength can reach 273.28 MPa, which is beneficial to improve the mechanical properties of rattan fiber reinforced composites. SEM images displayed the rough surface of the fiber, which helps to enhance the interfacial adhesion between the fibers and matrices in composites. This work was also in comparison with some other natural fibers. The above analysis and research showed the great potential of manau rattan fibers as the reinforcement in polymer-based composites.

scholarly journals Characterizing the Intrinsic Strength (Fatigue Threshold) of Natural Rubber/Butadiene Rubber Blends

2019 ◽  
Vol 47 (4) ◽  
pp. 292-307 ◽  
Author(s):  
Christopher G. Robertson ◽  
Radek Stoček ◽  
Christian Kipscholl ◽  
William V. Mars
Keyword(s):  
Energy Dissipation ◽  
Natural Rubber ◽  
Endurance Limit ◽  
Fatigue Threshold ◽  
Butadiene Rubber ◽  
Rubber Blends ◽  
Truck Tire ◽  
Rubber Compounds ◽  
Proper Account ◽  
Intrinsic Strength

ABSTRACT Tires require rubber compounds capable of enduring more than 108 deformation cycles without developing cracks. One strategy for evaluating candidate compounds is to measure the intrinsic strength, which is also known as the fatigue threshold or endurance limit. The intrinsic strength is the residual strength remaining in the material after the strength-enhancing effects of energy dissipation in crack tip fields are removed. If loads stay always below the intrinsic strength (taking proper account of the possibility that the intrinsic strength may degrade with aging), then cracks cannot grow. Using the cutting protocol proposed originally by Lake and Yeoh, as implemented on a commercial intrinsic strength analyzer, the intrinsic strength is determined for a series of carbon black (CB) reinforced blends of natural rubber (NR) and butadiene rubber (BR) typical of tire applications. The intrinsic strength benefits of the blends over the neat NR and BR compounds are only observed after aging at temperatures in the range from 50 to 70 °C, thus providing fresh insights into the widespread durability success of CB-filled NR/BR blends in tire sidewall compounds and commercial truck tire treads.

scholarly journals Underutilized Agricultural Co-Product as a Sustainable Biofiller for Polyamide 6,6: Effect of Carbonization Temperature

Molecules ◽  
2020 ◽  
Vol 25 (6) ◽  
pp. 1455 ◽  
Author(s):  
Thomas Balint ◽  
Boon Peng Chang ◽  
Amar K. Mohanty ◽  
Manjusri Misra
Keyword(s):  
Natural Fiber ◽  
Low Cost ◽  
Natural Fibers ◽  
Mechanical Analysis ◽  
Melt Viscosity ◽  
Soy Hull ◽  
Twin Screw ◽  
Different Temperatures ◽  
Soy Hulls ◽  
Soybean Industry

Polyamide 6,6 (PA66)-based biocomposites with low-cost carbonaceous natural fibers (i.e., soy hulls, co-product from soybean industry) were prepared through twin-screw extrusion and injection molding. The soy hull natural fiber was pyrolyzed at two different temperatures (500 °C and 900 °C denoted as BioC500 and BioC900 respectively) to obtain different types of biocarbons. The BioC500 preserved a higher number of functional groups as compared to BioC900. Higher graphitic carbon content was observed on the BioC900 than BioC500 as evident in Raman spectroscopy. Both biocarbons interact with the PA66 backbone through hydrogen bonding in different ways. BioC900 has a greater interaction with N-H stretching, while BioC500 interacts strongly with the amide I (C=O stretching) linkage. The BioC500 interrupts the crystallite growth of PA66 due to strong bond connection while the BioC900 promotes heterogeneous crystallization. Dynamic mechanical analysis shows that both biocarbons result in an increasing storage modulus and glass transition temperature with increasing content in the BioC/PA66 biocomposites over PA66. Rheological analysis shows that the incorporation of BioC900 results in decreasing melt viscosity of PA66, while the incorporation of BioC500 results in increasing the melt viscosity of PA66 due to greater filler–matrix adhesion. This study shows that pyrolyzed soy hull natural fiber can be processed effectively with a high temperature (>270 °C) engineering plastic for biocomposites fabrication with no degradation issues.

Sign in / Sign up

Export Citation Format

Share Document