Overall performance of natural rubber/graphene nanocomposites

Recently, aromatic oil (AO) is one of the substances that is typically used as a processing aid especially for high filler loadings in formulating rubber compound. Aromatic oil has disadvantages in that, it is hazardous to environment, toxic and has been labeled as carcinogenic. In this research, an epoxidised oil (EO) and aromatic oil were used to investigate the effect incorporation of oil onto the SBR/NR natural rubber vulcanizates (NR). From the result obtained, EO showed shorter cure time and scorch time as the oil loading were increased up to 20 pphr of EO. Physical properties such as hardness and rebound resilience of NR/EO vulcanisate were also investigated upon exposure to different humidity level in humidity chamber. At room temperature, the hardness of EO loading onto the SBR/NR vulcanisate is lower than AO loadings. Hardness was slightly decreased with increasing rate of humidity. There is great difference in hardness and rebound resilience values between AO and EO. Both hardness and rebound resilience were not affected by humidity. This implies the existence of good filler interaction with EO and rubber which do not impart changes in the hardness and resilience properties of rubber compound. Epoxidised oil has great promising potential to replace the carcinogenic aromatic oil as it has good overall performance and renewable in nature .

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Natural Rubber/Graphene Nanocomposites and Their Applications

Graphene Based Biopolymer Nanocomposites - Composites Science and Technology ◽

10.1007/978-981-15-9180-8_11 ◽

2020 ◽

pp. 203-220

Author(s):

K. B. Bhavitha ◽

Srinivasarao Yaragalla ◽

C. H. China Satyanarayana ◽

Nandakumar Kalarikkal ◽

Sabu Thomas

Keyword(s):

Natural Rubber ◽

Graphene Nanocomposites

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Effect of reinforcement on the barrier and dielectric properties of epoxidized natural rubber-graphene nanocomposites

Polymer Engineering & Science ◽

10.1002/pen.24131 ◽

2015 ◽

Vol 55 (11) ◽

pp. 2439-2447 ◽

Cited By ~ 22

Author(s):

Srinivasarao Yaragalla ◽

C. Sarath Chandran ◽

Nandakumar Kalarikkal ◽

R.H.Y. Subban ◽

Chin Han Chan ◽

...

Keyword(s):

Dielectric Properties ◽

Natural Rubber ◽

Epoxidized Natural Rubber ◽

Graphene Nanocomposites

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Properties of radiation vulcanised natural rubber latex (RVNRL)–graphene nanocomposites

Polymers and Polymer Composites ◽

10.1177/0967391118809438 ◽

2018 ◽

Vol 26 (8-9) ◽

pp. 461-472

Author(s):

K Anand ◽

Siby Varghese ◽

Thomas Kurian

Keyword(s):

Graphene Oxide ◽

Natural Rubber ◽

Filler Content ◽

Natural Rubber Latex ◽

Rubber Latex ◽

Elongation At Break ◽

Graphene Nanocomposites ◽

Exfoliated Graphene ◽

Green Route ◽

Reduced Graphene

Graphene-related materials such as graphene oxide (GO)/exfoliated graphene oxide (XGO) and reduced graphene oxide (RGO) recently achieved much interest in nanocomposite research. In this study, we report the synthesis of RGO by a green route, and its efficacy as a potential filler for radiation-vulcanised natural rubber latex (RVNRL) was explored. The synthesised XGO and RGO suspensions were characterised. The mechanical, morphological and electrical properties of the RVNRL-XGO/RGO nanocomposites were evaluated as a function of filler content. The percolation threshold of the RVNRL-RGO composite was 0.1 wt%. Compared with gum RVNRL, significant improvements in tensile strength and elongation at break were obtained for RVNRL-XGO nanocomposites at 1 wt% XGO loading, indicating increased polymer–filler interaction. The morphological results showed aggregation of filler particles at a concentration of 1.25 wt%.

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Extraction and identification of fillers and pigments from pyrolyzed rubber and tire samples

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163332 ◽

1996 ◽

Vol 54 ◽

pp. 174-175

Author(s):

P. Sadhukhan ◽

J. B. Zimmerman

Keyword(s):

Zinc Oxide ◽

Electron Microscope ◽

Carbon Black ◽

Natural Rubber ◽

Transmission Electron Microscope ◽

Rolling Resistance ◽

Synthetic Polymers ◽

Nitrogen Atmosphere ◽

Transmission Electron ◽

Curing Agents

Rubber stocks, specially tires, are composed of natural rubber and synthetic polymers and also of several compounding ingredients, such as carbon black, silica, zinc oxide etc. These are generally mixed and vulcanized with additional curing agents, mainly organic in nature, to achieve certain “designing properties” including wear, traction, rolling resistance and handling of tires. Considerable importance is, therefore, attached both by the manufacturers and their competitors to be able to extract, identify and characterize various types of fillers and pigments. Several analytical procedures have been in use to extract, preferentially, these fillers and pigments and subsequently identify and characterize them under a transmission electron microscope.Rubber stocks and tire sections are subjected to heat under nitrogen atmosphere to 550°C for one hour and then cooled under nitrogen to remove polymers, leaving behind carbon black, silica and zinc oxide and 650°C to eliminate carbon blacks, leaving only silica and zinc oxide.

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Electron sources: Past, present, and future

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100149659 ◽

1993 ◽

Vol 51 ◽

pp. 764-765

Author(s):

David C Joy

Keyword(s):

Glass Tube ◽

Source Size ◽

Electron Gun ◽

Operating Parameters ◽

Operational Parameters ◽

Electron Sources ◽

Difficult Decision ◽

Probe Size ◽

Wide Range ◽

Overall Performance

The electron source is the most important component of the Scanning electron microscope (SEM) since it is this which will determine the overall performance of the machine. The gun performance can be described in terms of quantities such as its brightness, its source size, its energy spread, and its stability and, depending on the chosen application, any of these factors may be the most significant one. The task of the electron gun in an SEM is, in fact, particularly difficult because of the very wide range of operational parameters that may be required e.g a variation in probe size of from a few angstroms to a few microns, and a probe current which may go from less than a pico-amp to more than a microamp. This wide range of operating parameters makes the choice of the optimum source for scanning microscopy a difficult decision.Historically, the first step up from the sealed glass tube ‘cathode ray generator’ was the simple, diode, tungsten thermionic emitter.

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Natural Rubber Materials

10.1039/9781849737654 ◽

2013 ◽

Cited By ~ 7

Keyword(s):

Natural Rubber

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Natural Rubber Materials

10.1039/9781849737647 ◽

2013 ◽

Cited By ~ 3

Keyword(s):

Natural Rubber

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A Comparison of Four Adolescent Language Tests

Language Speech and Hearing Services in Schools ◽

10.1044/0161-1461.1803.250 ◽

1987 ◽

Vol 18 (3) ◽

pp. 250-266 ◽

Cited By ~ 4

Author(s):

R. Jane Lieberman ◽

Ann Marie C. Heffron ◽

Stephanie J. West ◽

Edward C. Hutchinson ◽

Thomas W. Swem

Keyword(s):

Test Performance ◽

Sixth Grade ◽

Significant Discrepancy ◽

Language Impaired ◽

Language Functions ◽

Language Tests ◽

Significant Difference ◽

Sixth Grade Students ◽

Overall Performance ◽

Selection Of

Four recently developed adolescent language tests, the Fullerton Test for Adolescents (FLTA), the Test of Adolescent Language (TOAL), the Clinical Evaluation of Language Functions (CELF), and the Screening Test of Adolescent Language (STAL), were compared to determine: (a) whether they measured the same language skills (content) in the same way (procedures); and (b) whether students performed similarly on each of the tests. First, respective manuals were reviewed to compare selection of subtest content areas and subtest procedures. Then, each of the tests was administered according to standardized procedures to 30 unselected sixth-grade students. Despite apparent differences in test content and procedures, there was no significant difference in students' performance on three of the four tests, and correlations among test performance were moderate to high. A comparison of the pass/fail rates for overall performance on the tests, however, revealed a significant discrepancy between the proportions of students identified in need of further evaluation on the STAL (20%) and the proportion diagnosed as language impaired on the three diagnostic tests (60-73%). Clinical implications are discussed.

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