A Comparative Study on the Thermal Behaviour of Natural Rubber Filled with Carbon Black and Plant Residues

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Njukeng Jetro Nkengafac
Angel Alegria
Silvia Arrese- Igor
Adolphe Edgengele
Ehabe Eugene


Aims: A comparative study on the thermal behavior of natural rubber (NR) filled with different plant wastes and carbon black was carried out with the aim to evaluate green fillers that can replace carbon black filler in natural rubber vulcanisates for thermal applications.

Study Design: The plant wastes used for this study were carbonized and un carbonized cocoa pod husk, corncob and empty palm fruit bunch. Natural rubber vulcanisates filled with 10 phr carbon black (reference) and the various plant waste materials were prepared.

Methodology: The thermal behaviour of the vulcanisates and the fillers was studied by thermogravimetric analysis (TGA).  The glass transition temperature (Tg) for the vulcanisates was determined by differential scanning calorimetry (DSC). The shape of the decomposition curve was obtained from the derivative of the TGA curve (DTGA). The amount of residue remaining at various temperatures for the different samples was calculated from the TGA curve. Activation energies of degradation were calculated using Horowitz–Metzger equation. 

Results: The carbonised fillers and carbon black were more thermally stable than the un carbonised fillers and raw rubber. The decomposition behavior of vulcanisates followed a similar trend; with a single main decomposition peak at about 380°C. Samples with un carbonised fillers had higher residues than those filled with carbon black and carbonized plant wastes. From the activation energy values, it was found that vulcanisates, filled with carbonized corncob and carbonized cocoa pod husk were very close in thermal stability to those filled with carbon black and they were more stable than those filled with un carbonised plant wastes. DSC studies revealed that the fillers had non-significant effects on the Tg of the vulcanisates. This was evident from the very close nature of the Tg values for the different vulcanisates. Among the plant wastes studied, carbonised cocoa pod husk and corncob presented very close values of Ea and Tg to carbon black as fillers for raw natural rubber.

The vulcanisates with un carbonised fillers were less thermally stable than vulcanisates filled with carbonized fillers and carbon black. 

Degradation, glass transition, natural rubber, plant wastes.

Article Details

How to Cite
Nkengafac, N. J., Alegria, A., Igor, S. A.-, Edgengele, A., & Eugene, E. (2020). A Comparative Study on the Thermal Behaviour of Natural Rubber Filled with Carbon Black and Plant Residues. Journal of Materials Science Research and Reviews, 6(1), 21-30. Retrieved from https://journaljmsrr.com/index.php/JMSRR/article/view/30146
Original Research Article


Silva JM, Sanches AO, Malmonge LF, Malmonge JA. Electrical, mechanical, and thermal analysis of natural rubber/polyaniline-Dbsa composite. Mater Res. 2014;17:59–63.

Rolere S, Bottier C, Vaysse L, Sainte-beuve J, Bonfils F. Characterisation of macrogel composition from industrial natural rubber samples: Influence of proteins on the macrogel crosslink density. Express Polym.Lett. 2016;10(5):408–419.

DOI: 10.3144/expresspolymlett.2016.38

Jobish J, Vijayalakshmi R. Mechanical properties and swelling behavior of cross-linked natural rubber/chitosan blends. Int J Polym Anal Ch. 2009;(6):508-526.

DOI: 10.1080/10236660903072797

Ayo MD, Ekebafe LO, Chukwu MN, Madufor IC. Effect of carbonzation temperatures on the filler properties of groundnut shell powder. Int. J. Chem. 2011;21:55-58.

Cornish BSC. Characterization of agricultural and food processing residues for potential rubber filler applications. J. Compos. Sci. 2019;3(4):102.

DOI: 10.3390/jcs3040102

Eichhom SJ, Baillie CA, Zafeiropoulos N, Mwaikambo LY, Ansell MP, Dufresne A. Current international research into cellulosic fibres and composites. J. Mater. Sci. 2001;36(9):2107-3144.

Kumarjyoti R, Subhas CD, Lazaros T, Aphiwat P, Pranut P. Effect of various surface treatments on the performance of jute fibers filled natural rubber (NR) composites. polymers. 2020;12:369.

DOI: 10.3390/polym12020369

Mohanty AK, Misra M, Drzal LT. Sustainable bio-composites from renewable resources: Opportunities and challenges in the green materials world. J Polym Environ. 2002;(1/2):19-26.

Visakh PM, Thomas S, Oksman K, Mathew AP. Cellulose nanofibres and cellulose nanowhiskers based natural rubber composites: Diffusion, sorption, and permeation of aromatic organic solvents. J. Appl. Polym. Sci. 2012;124:1614-1623.

DOI: 10.1002/APP.35176

Chun KS, Husseinsyah S, Osman H. Modified cocoa pod husk-filled polypropylene composites by methacrylic acid. BioRes. 2013;8:3260–3275.

Koay SC, Salmah H. Polylactic acid/corn cob eco-composites: Effect of new coupling agent. J Thermoplast Compos Mater; 2013.

DOI: 10.1177/0892705712475008

Mayasari HE, Setyorini I, Yuniari A. Thermal degradation and swelling behaviour of acrylonitrile butadiene styrene rubber reinforced by carbon black. The 1st Materials Research Society Indonesia Conference and Congress IOP Publishing. IOP Conf. Series: Materials Science and Engineering. 2018;432:012041.

DOI: 10.1088/1757-899X/432/1/012041

Kaewpirom S, Worrarat C. Preparation and properties of pineapple leaf fiber reinforced poly (lactic acid) green composites. Fibers Polym. 2014;15:1469–1477.

Nikmatin S, Syafiuddin A, Kueh HAB, Maddu A. Physical, thermal, and mechanical properties of polypropylene composites filled with rattan nanoparticles. J Appl Res Technol. 2017;15(4):386–95.

Indrajati IN, Dewi IR, Nurhajati DW. Thermal properties of thermoplastic natural rubber reinforced by microfibrillar cellulose. IOP Conference Conf. Ser.: Mater. Sci. Eng. 2018;432:012038.

DOI: 10.1088/1757-899X/432/1/012038

Anoop KA. Thermal behavior of jute fibre and watermelon filled epoxy based bio-composite. IJSTE. 2018;4(12):115-119.

Ekweme L, Ogbobe O, Tenebe OG. Utilizationof palm kernel shell as filler in natural rubber composite. CAMIJ. 2016; 1(1):001-008.

Sawre BT, Akpobire D. Effect of egg shell and rice husk on hardness and swollen properties of natural rubber vulcanisates. IJOART. 2016;5(8):36-43.

Egbujuo WO, Anyanwu PI, Obasi HC. Utilization of chitin powder as afiller in natural rubber vulcanizates: In comparison with carbon black filler. IRASE. 2019;1-9.

DOI: 10.1556/1848.2020.00006

Kumar PRS, Avadhani N, Vijayakumar PC, Kalkornsurapranee, Johns J. Thermogravimetric and swelling studies on natural rubber based super elastomer. IJIRM. 2017;4(5):723-728.

DOI: 10.21276/ijirm.2017.4.4.10

Jing LC, Yern CC, Seng NG, Shaifulazuar R, Sabariah J. Effects of oil palm empty fruit bunch fiber on electrical and mechanical properties of conductive filler reinforced polymer composite. Biores; 2016.

DOI: 10.15376/biores.11.1.913-928

Abu BA. Mechanical, thermal and processing properties of oil palm empty fruit bunch-filled impact modified unplasticised poly (vinyl chloride) composites. Ph.D. Thesis, Universiti Teknologi Malaysia (UTM), Johor, Malaysia; 2006.

Santos RJ, Agostini DLS, Cabrera FC, Reis AP, Ruiz MR, Budemberg ER, Teixeira SR, Job AE. Sugarcane bagasse ash: New filler to natural rubber composite. Polímeros. 2014;24(6):646-653.


Mathew AP, Pakrisamy S, Thomas S. Studies on the thermal stability of natural rubber/polystyrene interpenetrating polymer networks: Thermogravimetric analysis. Polym Degrad Stab. 2001;72(3): 423-439.


Otoikhian KS, Adeniyi, AG, Dada AM, Ighalo JO. Assessment of carbonised wood-flour fillers on the mechanical properties of natural rubber vulcanisates. Eur. J. Sustain. Dev. Res. 2019;3(4): em0097.


Nabil H, Hanafi I, Suradet M, Abdulhakim M. Kinetic of thermal degradation and thermal stability of natural rubber filled with titanium dioxide nanoparticles. Polym Compos. 2019;40(8).

DOI: 10.1002/pc.25163

Kruzˇela ́JK, Dosoudil R, Hudec I. Thermooxidative aging of rubber composites based on NR and NBR with incorporated strontium ferrite. J. Elastomers Plast. 2018;50(1):71–91.


Maslowki M, Miedzianowska J, Strzelec K. Natural rubber composites filled with crop residues as an alternative to vulcanisates with common fillers. Polymers. 2019;11: 972.

DOI: 10.3390/polym11060972

Abdul SZAS, Hassan A, Ismail H. The effect of high purity rice husk silica synthesised using solvent-thermal extraction method on the properties of natural rubber compounds. BioResources. 2018;13(3):6936-6951.

Harun NAF, Baharuddin AS, Zainudin MHM, Bahrin EK, Naim MN, Zakaria R. Cellulase production from treated oil palm empty fruit bunch degradation by locally isolated Thermobifida fusca. Bioresources. 2013:8(1):676–687.

Chun KS, Husseinsyah S, Osman H. Mechanical and thermal properties of coconut shell powder filled polylactic acid biocomposites: Effect of the filler content and silane coupling agent. J. Polym. Res. 2012;19:1-8.

Salmah H, Koay SC, Hakimah O. Surface modificaiton of coconut shell powder filled polylactic acid biocomposites. J. Thermoplast. Compos. Mater; 2012.

DOI: 10.1177/0892705711429981

Chun KS, Husseinsyah S, Osman H. Properties of coconut shell powder-filled polylactic acid ecocomposites: Effect of maleic acid. Polym. Eng. Sci. 2013;53: 1109-1116.

Chakraborty S, Roy P, Pathak A, Debnath M, Dasgupta S, Mukhopadhyay R, Bandyopadhyay S. J Elast Plast. 2011;43: 499.

Otoikhian KS, Adeniyi AG, Dada AM, Ighalo JO. Assessment of carbonised wood-flour fillers on the mechanical properties of natural rubber vulcanisates. Eur. J. Sustain. Dev. Res. 2019;3(4): em0097.


Rao V, Johns J. Thermal behavior of chitosan/natural rubber latex blends: TG and DSC analysis. J Therm Anal Calorim. 2008;92(3):801–806.

Galiani PD, Malmonge JA, Soares BG, Mattoso CLH. Studies on thermal–oxidative degradation behaviours of raw natural rubber: PRI and thermogravimetry analysis. Plast Rubber Compos. 2013; 42(8):334-339.

DOI: 10.1179/1743289811Y.0000000046