scholarly journals Utilization of chitin powder as a filler in natural rubber vulcanizates: In comparison with carbon black filler

2020 ◽  
Vol 11 (1) ◽  
pp. 43-51
Author(s):  
Wisdom Okechukwu Egbujuo ◽  
Placid Ikechukwu Anyanwu ◽  
Henry Chinedu Obasi
Keyword(s):  
Tensile Strength ◽  
Carbon Black ◽  
Natural Rubber ◽  
Abrasion Resistance ◽  
Filler Content ◽  
Chemical Extraction ◽  
Local Market ◽  
Roll Mill ◽  
Crab Shell Waste ◽  
Natural Rubber Vulcanizates

AbstractNatural rubber (NR) vulcanizates were prepared from natural rubber and chitin using a two-roll mill. The chitin was extracted from crab shell waste obtained from a local market in Oron, Akwa Ibom State, Nigeria using the chemical extraction method. The effects of the chitin at different contents (0–40 phr) on the mechanical properties of the NR/Chitin vulcanizates with carbon black as reference filler have been investigated. The tensile strength of the chitin filled natural rubber (NCH), and the carbon black filled natural rubber (NCB) vulcanizates were found to increase with an increase in filler content to reach optimum at 30 phr after which it decreased. The hardness, impact and abrasion resistance properties of the NCH and NCB vulcanizates increased as filler content increases. The tensile strength and abrasion resistance of the vulcanizates containing blends of varying percentages of carbon black to chitin (CBCH) increased as more carbon black (CB) is introduced while the hardness and impact strength increased with increase in chitin content. However, carbon black filled vulcanizates showed better property enhancement than the chitin filler.

scholarly journals Effects of chemically treated and carbonized spear grass fibre on the curing and mechanical properties of natural rubber vulcanizates

2021 ◽  
Vol 39 (4) ◽  
pp. 1142-1149
Author(s):  
A.C. Ezika ◽  
V.U. Okpechi
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Carbon Black ◽  
Natural Rubber ◽  
Abrasion Resistance ◽  
Filler Loading ◽  
Carbonization Temperature ◽  
Compression Set ◽  
Chemically Treated ◽  
Natural Rubber Vulcanizates

Effects of chemically treated and carbonized spear grass fibre on the curing and mechanical properties of natural rubber vulcanizates were carried out. Natural rubber (NR) was filled with carbonized (at carbonization temperatures of 400°C, 600°C and 800°C  respectively) and chemically treated (treatment with HCl and NaOH of 5% concentration) spear grass fillers respectively, at a filler loading of 30phr. The rubber compounding was carried out in a bambury mixer. The effect of carbonization temperature and chemical treatment of the filler on the mechanical properties (tensile strength, % elongation, hardness strength, abrasion resistance and compression set) and rheological properties (cure time, scorch time, maximum and minimum torque) were carried out on the  samples. The results of the mechanical properties of carbonized spear grass fibre (C-SGF) filled vulcanizates show that the optimum carbonization temperature for an improved tensile strength, % elongation, hardness, abrasion and compression set was obtained at 400°C. NaOH treated fibre filled vulcanizates showed better mechanical properties; with the highest abrasion resistance of 67.65%, while untreated and acidified fibre filled vulcanizates showed poor mechanical properties. Acidified (HCl) uncarbonized spear grass fibre (U-SGF) filled vulcanizate had the highest compression set of 48% against C-SGF filled vulcanzates and carbon black filled  vulcanizate, with carbon black filled vulcanizate having 47% as its compression set value. This reveals that at a carbonization temperature of 400°C, C-SGF appears to be a potential substitute filler for carbon black (CB). Keywords: Spear Grass Fibre, Natural Rubber, Chemical Treatments, Cure Characteristics, Mechanical Properties, Carbonization

HAF/SILICA/NANOCLAY “TERNARY” MASTERBATCH AND HAF/SILICA BINARY MASTERBATCH FROM FRESH NATURAL RUBBER LATEX

2014 ◽  
Vol 87 (2) ◽  
pp. 250-263 ◽  
Author(s):  
Sasidharan Krishnan ◽  
Rosamma Alex ◽  
Thomas Kurian
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Carbon Black ◽  
Natural Rubber ◽  
Abrasion Resistance ◽  
Dynamic Properties ◽  
Natural Rubber Latex ◽  
Rubber Latex ◽  
X Ray ◽  
Filler Dispersion

ABSTRACT A process for production of carbon black/silica/nanoclay ternary filler masterbatch from fresh natural rubber (NR) latex was standardized. The fillers, nanoclay, carbon black, and silica were incorporated in fresh NR latex by a modified coagulation process. The latex, mixed with filler dispersions, coagulated immediately on addition of acids. The coagulum containing fillers was dried at 70 °C in an air oven to get the latex filler masterbatch, which was further processed in the conventional way. The masterbatch compounds containing only silica/carbon black showed a higher level of vulcanization as compared with the corresponding dry mixes. The mechanical properties, such as tensile strength, modulus, tear strength, abrasion resistance, and hardness, increased with the proportion of nanoclay in the mixes up to 5 phr, and with a greater amount, the change was only marginal. Lower tan delta values were observed for all of the masterbatches containing nanoclay in the ranges of 3 to 10 phr compared with the control dry mix containing 25/25 carbon black/silica. The improvement in mechanical properties and dynamic properties shown by the masterbatches over the conventional mill-mixed compounds was attributed to factors related to filler dispersion, as evidenced from the data from dispersion analyzer images, X-ray diffractograms, and a higher level of vulcanization.

Influence of Silanized-Silica and Carbon Black on the Cure and Mechanical Properties of Natural Rubber/Recycled Chloroprene Rubber (NR/rCR) Blends

2016 ◽  
Vol 1133 ◽  
pp. 191-195
Author(s):  
Siti Zuliana Salleh ◽  
Hanafi Ismail ◽  
Zulkifli Ahmad
Keyword(s):  
Tensile Strength ◽  
Carbon Black ◽  
Natural Rubber ◽  
Morphological Characterization ◽  
Filler Loading ◽  
Rubber Blends ◽  
Roll Mill ◽  
Cure Time ◽  
Chloroprene Rubber ◽  
Silanized Silica

The loadings effect of carbon black and silanized-silica filled 75/25 phr/phr of natural rubber/recycled chloroprene rubber (NR/rCR) blends were compared with the unfilled NR/rCR blends. Different filler loading between in the range of 10- 40 phr was used. The rubber blends were prepared by using a laboratory two-roll mill and rheometric characteristics were studied using the Monsanto moving die rheometer (MDR 2000) at 150 °C. The addition of CB and silanized-silica showed different trend in scorch and cure time but showed similar trend in torques. The incorporation of both fillers caused higher tensile strength than that unfilled rubber blends. By comparison, the silanized-silica filled NR/rCR blends showed higher tensile strength than CB filled NR/rCR blends. Morphological characterization as observed from SEM justified these results.

scholarly journals Properties Characterization of Vulcanized Natural Rubber Filled with Uncarbonized Particulate Cow Bone

2018 ◽  
Vol 3 (2) ◽  
Author(s):  
Akinlabi Oyetunji ◽  
Isiaka O Bakare ◽  
Reginald Umunakwe ◽  
Adetola O Adeyemo
Keyword(s):  
Tensile Strength ◽  
Carbon Black ◽  
Natural Rubber ◽  
Abrasion Resistance ◽  
Control Sample ◽  
Filler Loading ◽  
Rubber Composites ◽  
Compression Moulding ◽  
Natural Rubber Composites ◽  
Cow Bone

This work investigates the effects of addition of 63 µm uncarbonized particulate cow bone as fillers in vulcanized natural rubber on the tensile properties, hardness and abrasion resistance of the composites. Cow bones were procured from an abattoir, cleaned, crushed, pulverized, ball milled and sieved to obtain the particles that passed through the 63 µm mesh size. Natural rubber composites materials were prepared varying the filler loading as 5, 10, 15 and 20 pphr respectively. The compounded rubber samples were cured in a hot press using compression moulding technique. The control sample was produced using 20 pphr of carbon black. The cured rubber samples were conditioned at room temperature for two weeks before they were characterized. The tensile strength and elastic modulus of the samples filled with cow bone increased with filler loading up to 15 pphr before they started decreasing. Carbon black reinforced sample possessed higher tensile strength, modulus and hardness than the samples filled with uncarbonized particulate cow bone. The hardness for all samples maintained an increasing trend with increase in the filler loadings. Particulate cow bone reinforced natural rubber offered higher elongation than carbon black reinforced samples. At 10, 15 and 20 pphr, cow bone reinforced composites exhibited higher abrasion resistance than carbon black filled sample. The optimal filler loading of uncarbonized particulate cow bone reinforced natural rubber was 15 pphr.  Cow bone reinforced natural rubber can find applications in areas where moderate strength, hardness, elongation and wear resistance are required such as in protective footwear, bouncing balls and cases of children toys.Keywords— carbon black, cow bone, fillers, natural rubber, composites.

scholarly journals The effect of carbon black on the curing and mechanical properties of natural rubber/ acrylonitrile- butadiene rubber composites

2021 ◽  
Vol 19 (3) ◽  
pp. 194-201
Author(s):  
H. Boukfessa ◽  
B. Bezzazi
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Carbon Black ◽  
Natural Rubber ◽  
Abrasion Resistance ◽  
Tensile Modulus ◽  
Butadiene Rubber ◽  
Rubber Composites ◽  
Acrylonitrile Butadiene Rubber ◽  
Different Content

The present work investigates the effect of the amount of carbon black on curing and mechanical properties such as tensile strength, elongation at break, hardness and abrasion resistance of the natural rubber (NR)/ acrylonitrile-butadiene rubber (NBR) blend. For that purpose, a blend composed of 65% NR and 35% NBR filled with different content of carbon black N330 was used. The curing results indicate that the viscosity and the crosslink density of rubber composites increase and the scorch and curing times decrease with increasing the filler content. Mechanical properties such as tensile modulus and hardness of the CB filled NR/NBR blend were remarkably improved, indicating the inherent reinforcing potential of CB. Regarding tensile strength and abrasion resistance, they increase with the addition of carbon black, up to 50 phr. After that, these properties decrease slightly with filleraddition.

NATURAL RUBBER/CARBON BLACK NANOCOMPOSITES PREPARED BY ULTRASONICALLY AIDED EXTRUSION

2013 ◽  
Vol 86 (4) ◽  
pp. 633-652 ◽  
Author(s):  
Jaesun Choi ◽  
Avraam I. Isayev
Keyword(s):  
Tensile Strength ◽  
Carbon Black ◽  
Natural Rubber ◽  
Ultrasonic Treatment ◽  
Abrasion Resistance ◽  
Chain Scission ◽  
Ultrasonic Waves ◽  
Ultrasonic Power ◽  
Bound Rubber ◽  
And Performance

ABSTRACT Significant efforts have been made in rubber research to improve the dispersion of carbon black (CB) in rubbers to achieve better processibility and performance of tires and rubber products. In addressing these issues, the present study is an attempt to further improve the processibility and dispersion by means of application of ultrasonic waves. Natural rubber (NR)/CB nanocomposites at loadings from 15 to 60 phr were prepared by ultrasonically aided extrusion at ultrasonic amplitudes up to 7.5 μm. A die pressure significantly decreased with an increase of amplitude, especially at higher loadings, indicating an improvement in processibility. Ultrasonic power consumption was almost insensitive to loadings. The complex dynamic viscosity, storage, and loss moduli of compounds and vulcanizates at loadings of 15, 25, 35, and 60 phr were reduced by the ultrasonic treatment at an amplitude of 7.5 μm, indicating NR chain scission. Bound rubber in compounds decreased by the ultrasonic treatment. The maximum torque in curing curves, cross-link density, gel fraction, hardness, M100, M300, tensile strength, and abrasion resistance of vulcanizates at loadings of 15, 25, 35, and 60 phr decreased at an amplitude of 7.5 μm, due to the NR chain scission, whereas the elongation at break increased. Atomic force microscope (AFM) studies of vulcanizates showed a penetration of rubber chains into agglomerates at an amplitude of 7.5 μm, indicating an improvement of dispersion of CB. Based on AFM images, a dispersion index was introduced, showing that the ultrasonic treatment at an amplitude of 7.5 μm led to a better dispersion of CB in vulcanizates. Comparison of NR/CB compounds and vulcanizates with those of NR/carbon nanotube (CNT) of an earlier study was carried out. In general, the CB-containing NR showed significantly lower modulus and abrasion resistance but higher tensile strength and bound rubber than CNT-containing NR.

Effect of Diameter and Surface Area of Carbon Black Particles on Certain Properties of Rubber Compounds

1944 ◽  
Vol 17 (2) ◽  
pp. 451-474
Author(s):  
D. Parkinson
Keyword(s):  
Particle Size ◽  
Tensile Strength ◽  
Carbon Black ◽  
Abrasion Resistance ◽  
Particle Diameter ◽  
Stiffness Modulus ◽  
Carbon Structures ◽  
Rubber Compounds ◽  
Regular Manner ◽  
Tear Resistance

Abstract Carbon blacks can be grouped into different classes according to the way in which their fineness of division relates to different properties in rubber. Within any one class the principal properties vary in a regular manner with particle size. The normal class consists of the furnace carbons, Kosmos (Dixie)-40, Statex, the rubber-grade impingement carbons, and possibly, the color-grade impingement carbons. The subnormal classes consist of thermal carbons and acetylene and lamp blacks. Irrespective of the above classification, the properties which depend more on fineness of division than on other factors are rebound resilience, abrasion resistance, tensile strength and tear resistance. The lower limit of particle diameter for best tensile strength and tear resistance appears to be higher than that for abrasion resistance. B.S.I, hardness and electrical conductivity are properties which depend at least as much on other factors as on particle size. Stiffness (modulus) depends more on other factors than on particle size. Factors modifying the effects of particle size (or specific surface) include the presence of carbon-carbon structures and a reduction in strength of bond in rubber-carbon structures. Carbon black is thought to exist in rubber in four states: agglomerated, flocculated, dispersed, and bonded to the rubber molecules (the reënforcing fraction). Abrasion resistance is regarded as providing the only reliable measure of reënforcement.

EFFECT OF DEVULCANIZATION ON CROSSLINK DENSITY AND CROSSLINK DISTRIBUTION OF CARBON BLACK FILLED NATURAL RUBBER VULCANIZATES

2016 ◽  
Vol 89 (4) ◽  
pp. 653-670 ◽  
Author(s):  
Anu Mary Joseph ◽  
Benny George ◽  
Madhusoodanan K. N. ◽  
Rosamma Alex
Keyword(s):  
Carbon Black ◽  
Natural Rubber ◽  
Crosslink Density ◽  
Morphological Properties ◽  
Original Sample ◽  
Ambient Conditions ◽  
Absolute Value ◽  
Roll Mill ◽  
Percentage Retention ◽  
The Absolute

ABSTRACTCarbon black filled natural rubber (NR) vulcanizates were devulcanized at ambient temperature in a two roll mill. The effect of cure system, that is, conventional vulcanization (CV), semiefficient vulcanization (semi EV), and efficient vulcanization (EV) systems, used for vulcanization of the original sample, on the efficiency of devulcanization was studied. The efficiency of devulcanization expressed as percentage devulcanization of the samples calculated from residual crosslink density measurements was correlated with the sol fraction of the devulcanized samples based on Horikx analysis. Using chemical probe analysis, we determined (i) the crosslink distribution pattern of the original sample, (ii) the extent to which the different types of crosslinks—that is, polysulfidic, disulfidic, and monosulfidic crosslinks—have been debonded or broken during the shearing process in the two roll mill, and (iii) the pattern of bond formation during revulcanization. Mechanical shearing predominantly breaks the majority crosslink type (polysulfidic crosslinks in CV and semi EV cure systems and disulfidic crosslinks in EV samples). Irrespective of the significant reduction in total crosslink density in all three sets of samples, chain shortening reactions similar to the post-crosslinking chemical reactions at curing temperatures also occur during mechanical shear at ambient conditions, which increased the absolute value of monosulfidic links in CV and semi EV systems. However, in the devulcanized EV system, the absolute value of polysulfidic crosslinks increased, which might be due to the re-crosslinking of the cleaved bonds. All the devulcanized samples were revulcanized, and the mechanical and morphological properties were analyzed. The percentage retention of the vulcanizate properties after revulcanization of the devulcanized samples correlated very well with efficiency of devulcanization.

scholarly journals Thermal, Morphological and Physic-Mechanical Properties of Natural Rubber - CaCO3 Composites Using Jatropha Oil as Softener.

2018 ◽  
Vol 156 ◽  
pp. 05016 ◽  
Author(s):  
Nasruddin ◽  
Tri Susanto
Keyword(s):  
Tensile Strength ◽  
Natural Rubber ◽  
Abrasion Resistance ◽  
Compositional Analysis ◽  
Critical Issue ◽  
Green Technology ◽  
Jatropha Oil ◽  
Rubber Composites ◽  
Elongation At Break ◽  
Natural Rubber Composites

The urgency of green technology in rubber compounding has become a critical issue recently. In this research, the effect of using renewable resources in rubber compounding has been studied. Commercial Calcium Carbonate, Silica and Jatropha Oil were used in natural rubber composite. The research was designed by varying the types of commercial filler namely CaCO3 (47-51) phr, silica (47-51) phr and Jatropha Oil (4-6) phr in natural rubber composites (SIR-20). The formulas were intentionally designed for rubber tips vulcanizates. The samples were characterized by the determination of physic-mechanical, thermal (TGA) and morphological (SEM) properties. From the measured results, there is no significant effect on the tensile strength, specific gravity, and hardness on the loading of commercial CaCO3 and Silica in natural rubber composites using Jatropha Oil. However, a slight difference in elongation at break and abrasion resistance could be detected. Compared to the commercial rubber tips, the rubber tips produced in this research have higher tensile strength, elongation at break and abrasion resistance. Due to the usage of commercial CaCO3 and Silica, the SEM micrographs show rough surface because of the agglomeration. The thermogram shows clearly the compositional analysis of the rubber tips vulcanizates consist of Jatropha Oil and natural rubber, CaCO3, ash and other filler residues such as Silica.

Sign in / Sign up

Export Citation Format

Share Document