Properties Of Natural Rubber Composites Research Articles

Effects of modified coal gasification fine slag on the processing and mechanical properties of natural rubber composites

AbstractCoal gasification fine slag (CGFS) is rich in unburned residual carbon, silica and alumina, and has a large specific surface area, making it a potential polymer‐reinforcing filler. Tea polyphenol (TP)‐modified coal gasification fine slag (TP‐CGFS‐T) was prepared using flotation and modification methods in this study. The effects of unmodified and modified CGFS‐T on the sulfurization performance, processing properties, thermal stability, fracture morphology, and mechanical properties of natural rubber composite materials were investigated. Results indicated that after TP modification, CGFS‐T exhibited highly uniform dispersion on the surface without the agglomeration of fillers. When the dosage of TP‐CGFS‐T was 20 phr, the comprehensive performance of the natural rubber (NR) composite material was optimal, with a tensile strength of 12.12 MPa, the elongation at break of 1208.83%, the tear strength of 30.94 kN/m, and the shore hardness of 38.7 A. As the amount of TP‐CGFS‐T increased, the scorch time of NR increased, which enhanced the processing safety of rubber. This study provides a strategy for treating CGFS, which can both reduce the pollution caused by CGFS and save costs for NR composite materials.Highlight The CGFS is separated into concentrate and tailings by flotation. The compatibility between fillers and the matrix is enhanced by TP modification of CGFS‐T. The composite materials show excellent mechanical and processing properties.

Effect of ground tyre rubber content on self-healing properties of natural rubber composites

Abstract In this investigation, we study the influence of the loading of ground tyre rubber (GTR), referred to as rubber dust 40 mesh (RD40), on the intrinsic self-healing natural rubber (NR) based on metal-thiolate ionic networks. The loading of RD40 particles was varied at 10, 20, and 30 phr to assess the optimum amount for interfacial bonding, mechanical and dynamic properties, and healing efficiency. The quantitative measurement of metal-thiolate ion networks and covalent crosslinks was assessed through swelling tests. The effects of RD40 loading on the dynamic mechanical properties and morphological characteristics were also investigated. Tensile properties of the rubbers before and after healing were measured using universal testing tester to obtain healing efficiency of the materials. The results showed that the developed materials have the ability to autonomously repair themselves at room temperature without the need for manual intervention. The results also revealed the tensile strength and elongation at break of self-healing NRs filled with 10 phr of RD40 were recovered 92 % and 93 %, respectively. The findings demonstrated the benefits of utilizing GTR as an effective sustainable filler and advanced the understanding of self-healing strategies and the interaction between ground tyre rubber and rubber matrices.

Comparative Investigation of Nano-Sized Silica and Micrometer-Sized Calcium Carbonate on Structure and Properties of Natural Rubber Composites.

Fillers have been widely used in natural rubber (NR) products. They are introduced to serve as a strategy for modifying the final properties of NR vulcanizates. Silica and calcium carbonate (CaCO3) are among the fillers of choice when the color of the products is concerned. In this case, a special focus was to compare the vulcanizing efficiency of NR filled with two different filler types, namely nano-sized silica and micrometer-sized CaCO3. This study focused on the effects of the loading level (10-50 parts per hundred parts of rubber, phr) on the final properties and structural changes of NR composites. The results indicated that increased filler loading led to higher curing torques and stiffness of the rubber composites irrespective of the type of filler used. The better filler dispersion was achieved in composites filled with CaCO3 which is responsible for less polarity of CaCO3 compared to silica. Good filler distribution enhanced filler-matrix interactions, improving swelling resistance and total crosslink density, and delaying stress relaxation. The modulus and tensile strength of both composites also improved over the content of fillers. The CaCO3-filled composites reached their maximum tensile strength at 40 phr, exceeding, by roughly 88%, the strength of an unfilled sample. Conversely, the maximum tensile strength of silica-filled NR was at 20 phr and was only slightly higher than that of its unfilled counterpart. This discrepancy was ascribed to the stronger rubber-filler interactions in cases with CaCO3 filler. Effective rubber-filler interactions improved strain-induced crystallization, increasing crystallinity during stretching and reducing the strain at which crystallization begins. In contrast, large silica aggregates with poor dispersion reduced the overall crosslink density, and degraded the thermomechanical properties, tensile properties, and strain-induced crystallization ability of the NR. The results clearly indicate that CaCO3 should be favored over silica as a filler in the production of some rubber products where high performance was not the main characteristic.

Use of ZIF‐8 as vulcanization additive to optimize natural rubber composites to lower the amount of ZnO

AbstractZinc oxide (ZnO) is widely used as an activator in the vulcanization process of natural rubber. However, due to its poor compatibility with natural rubber, a large amount of ZnO needs to use, and the unreacted ZnO can precipitate in various ways, posing significant harm to aquatic organisms and microorganisms. Therefore, it is necessary to reduce the dosage of ZnO in order to minimize its environmental impact. In this study, we applied ZIF‐8, a zinc‐based metal–organic framework, as a vulcanization additive in natural rubber. and it was found that ZIF‐8 could promote the rubber vulcanization reaction by adsorbing sulfur, promoting sulfur ring‐opening, and providing different ligand interactions of Zn2+. Moreover, even at low usage levels of ZIF‐8, it effectively reduces the amount of ZnO while simultaneously improving the mechanical properties of the samples. This work provides an effective method to reduce the amount of ZnO without sacrificing the rubber properties and provides a new idea for the application of ZIF‐8 in rubber materials.Highlights ZIF‐8 enhances properties of natural rubber composites with low ZnO dosages. Revealing the reason why ZIF‐8 promotes the vulcanization of natural rubber. Investigation of the effect of ZIF‐8 on the vulcanization properties of natural rubber.

Effect of the ratio of carbon nanotubes and carbon black on the properties of natural rubber

In this experiment, the effect of carbon nanotubes (CNTs) replacing some carbon black (CB) on the properties of natural rubber composites was investigated. 5 phr of CNTs were used to replace part of CB in the ratio of m(CNTs) : m(CB reduction) = 1 : X (X from 1 to 4.5). The properties of the vulcanized rubber such as vulcanization, thermal conductivity, tensile, heat generation and processing were investigated experimentally. The results showed that when the ratio of CNTs/CB(reduction) was 1:1, it could substantially improve the crosslink density of the sample and reduce the vulcanization time, while having better processing safety and having the best thermal conductivity. At this time, 5 phr of CNTs and 40 phr of CB were added to the sample, and the dispersion of CB and CNTs in the sample was studied by CB dispersion tester and rubber processing analyzer. The tensile property change regularity tested by rubber tensile tester matched with the experimental results of CB dispersion tester and rubber processing analyzer. When the ratio of CNTs/CB(reduction) was 1:1, it increased the heat generation of the sample significantly. When the ratio of CNTs/CB(reduction) was 1:3.5, all the properties of the sample were better than those of the 1# sample.

Innovative design: Flexible conductive natural rubber electrode sheets with triboelectric generator activated by wheel rotation

Efficient consumption and clean energy management play a vital role in green energy. To be a part of this effort. Among the materials explored, flexible conductive electrodes utilizing triboelectric phenomena and unique properties of natural rubber composites have demonstrated a great potential for mechanical-to-electrical energy conversion. Fabrication process involves modifying natural rubber latex by incorporating conductive fillers such as carbon black, Ketjen black, and multiwall carbon nanotubes. The modified flexible conductive natural rubber sheets (CNRs) are then characterized for their structural and electrical properties. This structural arrangement significantly reduces the electrical resistance of the NR sheets. The incorporation of the MWCNT fillers leads to an increase in dielectric constant of CNRs. These properties are optimized via a proper design of the conductive natural rubber sheet triboelectric nanogenerator (CNRS-TENG). To enhance charge accumulation, polytetrafluoroethylene (PTFE) film is applied to the bottom surface of the CNRs. The CNRS-TENG are integrated into a wheel rotation generator setup. The output performance of the wheel rotation generator is influenced by the rotational speed as well as the arrangement of phases and segments. This work demonstrates that CNRs can be integrated with flexible electronic and other energy harvesting devices, opening possibilities for multifunctional clean energy solutions.

Effect of disaggregation and activation of sepiolite on interfacial interaction and mechanical properties of natural rubber/sepiolite composites prepared by latex compounding method

AbstractThe demand for environmentally friendly and non‐petroleum based natural rubber products is on the rise. Sepiolite, a one‐dimensional clay mineral, has been found to be a suitable reinforcement for natural rubber through latex compounding. However, the aggregation of fibers and minerals may impact the overall properties of natural rubber composites. To overcome this challenge, the study utilized ultrasonic disaggregation and oxalic acid activation to prepare stable sepiolite suspensions with varying specific surface areas and surface activities. These suspensions were then mixed with natural rubber latex to prepare NR/sepiolite composites. The results showed that the dispersibility and bonding ability of sepiolite with natural rubber were improved due to the increased specific surface area and surface activity, resulting in more bonding sites. The mechanical properties of the composites were also found to be improved, with a significant increase in tear strength (from 61.9 to 67.6 N·mm−1) and tensile strength (from 23.0 to 29.5 MPa). This research lays a strong foundation for the utilization of sepiolite in rubber materials.

Synthesis of copper-grafted graphite and its effect on properties of natural rubber composites

Conductive polymer composites, which are extensively applied in the fields of sensors, batteries, memory materials, etc. possess some significant properties mainly high electrical conductivity and good mechanical performance. In this study, copper (Cu) was grafted onto the graphite surface according to a chemical process. The Cu-grafted graphite (Cu-g-graphite) was characterized via fourier transform infrared spectroscopy (FTIR), X-ray diffraction spectroscopy (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM), where the analysis proved that Cu was successfully grafted onto the graphite surface. Subsequently, natural rubber (NR) composites were prepared by varying the Cu-g-graphite loading from 0 phr (parts per hundred rubber) to 10 phr at 2 phr intervals. The 8 phr Cu-g-graphite filled NR composite showed better physico-mechanical properties in comparison with the other Cu-g-graphite composites and the NR composite prepared without Cu-g-graphite (control). Also, the former composite showed better thermal ageing and electrical conductivity which are requirements for sensor applications. Further, electrical conductivity of the Cu-g-graphite/NR composites prepared with greater than 4 phr loading of Cu-g-graphite was at a high level. Furthermore, the Cu-g-graphite filled NR composites indicated a remarkable improvement in electrical conductivity compared to that of the control. Finally, the performance of NR composite prepared with 8 phr loading of Cu-g-graphite in overall showed a considerable level of applicability for high electrical, thermal and physico-mechanical polymeric applications.

Multi-Layered Composites of Natural Rubber (NR) and Bismuth Oxide (Bi2O3) with Enhanced X-ray Shielding and Mechanical Properties.

Due to rapid increases in the utilization of radiation and nuclear technologies, effective and suitable radiation-shielding materials have become one of the most sought-after options to protect users and the public from excessive exposure to the radiation. However, most radiation-shielding materials have greatly reduced mechanical properties after the addition of fillers, resulting in their limited useability and shortened lifetime. Therefore, this work aimed to alleviate such drawbacks/limitations by exploring a possible method to simultaneously enhance both the X-ray shielding and mechanical properties of bismuth oxide (Bi2O3)/natural rubber (NR) composites through multi-layered structures, with varying (1-5) layers and a total combined thickness of 10 mm. To correctly determine the effects of the multi-layered structures on the properties of NR composites, the formulation and layer configuration for all multi-layered samples were tailored such that their theoretical X-ray shielding properties were equal to those of a single-layered sample that contained 200 phr Bi2O3. The results indicated that the multi-layered Bi2O3/NR composites with neat NR sheets on both outer layers (sample-D, sample-F, sample-H, and sample-I) had noticeably higher tensile strength and elongation at break than those of the other designs. Furthermore, all multi-layered samples (sample-B to sample-I), regardless of the layer structure, had enhanced X-ray shielding properties compared to those with a single layer (sample-A), as shown by their higher values of the linear attenuation coefficient (µ) and lead equivalence (Pbeq) and the lower value of the half-value layer (HVL) in the former. This work also determined the effects of thermal aging on relevant properties for all samples, with the results revealing that all the thermal-aged composites had higher values for the tensile modulus but lower values for the swelling percentage, tensile strength, and elongation at break, compared with the non-aged composites. Hence, based on the overall outcomes from this work, it could be concluded that the worrisome decreases in mechanical properties of the common single-layered NR composites after the addition of Bi2O3 could be prevented/reduced by introducing appropriate multi-layered structures, which would not only widen potential applications but also prolong the lifetime of the composites.

Novel application of Zn‐containing Zeolitic Imidazolate Frameworks in promoting the vulcanization and mechanical properties of natural rubber composites

AbstractThree kinds of Zn‐containing Zeolitic Imidazolate Frameworks (Zn‐ZIFs, including ZIF‐8, ZIF‐11 and ZIF‐14) based on the zinc ions coordinating with different imidazolate ligands were added into the natural rubber (NR) using the DM and TMTD binary accelerators system, respectively. The influences of Zn‐ZIFs on the sulfur vulcanization behaviors and mechanical properties of NR matrix were evaluated. The results indicated that the addition of ZIF‐8 or ZIF‐14 could realize the fast vulcanization of NR at 130°C (the ordinary vulcanization temperature of NR is above 150°C), while ZIF‐11 did not show the obvious accelerating performance. Amongst the three Zn‐ZIFs, ZIF‐8 benefited NR matrix for the acquirement of the highest tensile strength and the largest crosslinking density. As an optimal additive, ZIF‐8 with 0.6 phr distinctly improved the physical‐mechanical, thermo‐oxidative aging resistance and dynamic mechanical properties of NR composites. It proved that Zn atom and its coordination porous network in Zn‐ZIFs played synergistic effects in accelerating vulcanization and enhancing mechanical properties of NR matrix besides its role of reinforcement filler. Then the above ZIF‐8/DM/TMTD vulcanization system was used to prepare the UHMWPE fibers/NR composites. The mechanical properties of the UHMWPE/NR composites were significantly improved in contrast to the pure NR matrix.

Preparation and mechanical properties of natural rubber composites reinforced by modified molybdenum disulfide

AbstractThe filler‐rubber interaction and filler dispersion in natural rubber (NR) composites are important factors in determining mechanical properties. Herein, Molybdenum disulfide (MoS2) and Al2O3‐coated MoS2 nanospheres are incorporated in NR/carbon black composites. The effects of MoS2 and Al2O3‐coated MoS2 on the morphology, thermal and mechanical properties of the NR composites are investigated. The morphology analysis indicates that Al2O3‐coated MoS2 could greatly improve the dispersion of carbon black in NR composites. MoS2 filler and carbon black show a synergetic effect on improving the properties of NR composites, leading to high abrasion resistance, tensile strength, elongation at break and expected dynamic mechanical properties. The thermal conductivity of NR composites increases with increasing the content of MoS2 and Al2O3‐coated MoS2. The thermal stability of the NR composites is also effectively improved by filling MoS2 and Al2O3‐coated MoS2. Furthermore, a small amount of Al2O3‐coated MoS2 significantly improves the abrasion resistance, wet grip and decreases rolling resistance of the composites. Al2O3‐coated MoS2 exhibits its potential application in green tires with good performance.

Enhancing Compatibility and Mechanical Properties of Natural Rubber Composites

Pure natural rubber (NR) exhibits low mechanical properties, necessitating the incorporation of additives like vulcanizing agents and fillers. Carbon black and silica, conventional fillers, are relatively expensive and not environmentally friendly. This study explores using Oil Palm Empty Fruit Bunch (OPEFB) fiber as an affordable, abundant, and biodegradable alternative filler for NR. However, compatibility issues arise between the nonpolar NR and the polar OPEFB fiber. A latex-starch hybrid coupling agent (CA (NR-St)) was added to the composite formulation to address this. NR, OPEFB fiber, and the coupling agent were mixed using an open roll mill with a 10 phr OPEFB filler loading and coupling agent concentrations of 0, 1, 2, and 3 phr. Fourier-transform infrared spectroscopy (FTIR), rheology, and mechanical property tests revealed that the coupling agent improved the compatibility between NR and OPEFB fibers, as evidenced by increased tensile strength and stiffness. The composite with 3-phr coupling agent exhibited the best performance with tensile strength and stiffness values of 25.6 MPa and 3.7 MPa, respectively. This increase in mechanical properties has the potential to act as a catalyst for increasing the use of renewable materials in the rubber industrial sector, especially the automotive industry.

Effects of fiber surface modification on mechanical properties of short pineapple leaf fiber-carbon black reinforced natural rubber hybrid composites

At present, the world is focusing on the circular economy by turning waste into production resources again, reducing waste generation, and making it circulate in the system. This research focuses on using agricultural waste, which is pineapple leaves abundant in Thailand, to be processed into pineapple leaf fibers (PALF) and used to reinforce natural rubber. PALF has relatively high strength when compared to other natural fibers. On the other hand, the challenge of using PALF to reinforce natural rubber is the difference in the polarity of the fibers and rubber matrix. Thus, surface modification of PALF was studied to enhance the adhesion between the fiber surface and the matrix. Four systems were compared, i.e., untreated PALF, alkaline-treated, silane69-treated, and aminosilane-treated PALF. A unidirectional fiber-reinforced natural rubber composites were prepared with fixed fiber and carbon black contents of 10 and 30 phr, respectively. Mechanical properties of the composites were determined by tensile test and morphology was observed by scanning electron microscope (SEM). It was found that silane69-treated and aminosilane-treated PALF could reinforce the rubber matrix over the entire strain. However, silane69-treated and aminosilane-treated PALF had lesser reinforcement effect than alkaline-treated PALF at low strains. Despite a clear change in mechanical behavior, SEM could not tell the difference or changes that occur at the interface. Fiber surface modifications with silane69 and aminosilane have the potential to be further developed to improve properties of natural rubber composites and will, hopefully, increase the value of rubber products for Thailand industry.

Effect of Different Silane Coupling Agents In-Situ Modified Sepiolite on the Structure and Properties of Natural Rubber Composites Prepared by Latex Compounding Method

With the increasing demand for eco-friendly, non-petroleum-based natural rubber (NR) products, sepiolite, a naturally abundant, one-dimensional clay mineral, has been identified as a suitable material for reinforcing NR through the latex compounding method. To create superior NR/sepiolite composites, three silane coupling agents with different functional groups were used to modify sepiolite in situ via grafting or adsorption during the disaggregation and activation of natural sepiolite, which were subsequently mixed with natural rubber latex (NRL) to prepare the composites. The results showed that the modified sepiolite improved the dispersion and interfacial bonding strength with the rubber matrix. VTES-modified sepiolite containing C=C groups slightly improved the performance but retarded the vulcanization of the NR composites, and MPTES and TESPT-modified sepiolites containing -SH and -S4- groups, respectively, effectively accelerated vulcanization, inducing the composites to form a denser crosslink network structure, and exhibiting excellent dynamic and static properties, such as the modulus at a 300% increase from 8.82 MPa to 16.87 MPa, a tear strength increase from 49.6 N·mm-1 to 60.3 N·mm-1, as well as an improved rolling resistance and abrasive resistance of the composites. These findings demonstrate that modified sepiolite can be used to produce high-quality NR/sepiolite composites with enhanced properties.

Synthesis of polyethylene glycol-grafted graphite and effect of its loading on properties of natural rubber composites

The Journal of the National Science Foundation of Sri Lanka publishes the results of research in all aspects of Science and Technology. The journal also has a website at http://www.nsf.gov.lk/. 2021 Impact Factor: 0.682The JNSF provides immediate open access to its content on the principle that making research freely available to the public supports a greater global exchange of knowledge.Cover :Leatherback (a), green (b - adult & f - hatchling), hawksbill (c) and olive ridley (d) turtles who nest in Sri Lankan beaches, green turtle crawl marks (e) and by-catch of sea turtles in fisheries (c & d)Photo credits: SJ Perera (a & c), WPN Perera (b & e), K Ekaratne (d & f)

Utilization of high and low calcium oxide fly ashes as the alternative fillers for natural rubber composites: A waste to wealth approach

Recently, fillers from renewable resources or agricultural wastes have been considered as the alternative fillers to reduce the environmental problems. Therefore, utilization of the fly ashes (FA) collected from the electric power plants as the reinforcing filler in natural rubber (NR) composites was carried out and compared these high (HCaO) and low (LCaO) calcium oxides with carbon black (CB). The FA concentration was varied up to an optimum loading of 1000 parts per hundred rubber (phr) by using melt mixing technique. Particle size and chemical composition of HCaO and LCaO were reported and the properties of NR composites in terms of cure characteristics, Payne effect, mechanical and dynamical properties together with morphologies were examined. It was found that the addition of HCaO significantly reduced the vulcanization time of the NR composites, while the one with LCaO provided higher degree of reinforcement efficiency to the NR matrix. It clearly supports the relation of storage modulus as a function of strain sweep and their morphologies, which are the major requirements in case of composites. Upon increasing of FA loading, NR has changed its role from rubber matrix to an adhesive binder and therefore the Young’s modulus was found to be strongly changed. FA can be used to replace CB in NR composites with the composition ratios starting from 1:2–1:6 phr. Although, CB exhibited a slightly better reinforcing effect than FA, based on the lowered glass transition temperature (Tg), Tan delta (Tan δ) exhibited the same elasticity and CB can be replaced in case of several CB-based composites, particularly, the artificial wood, car stopper and tire industries to produce rubber belt and bead.

Comprehensive experimental investigations and theoretical predictions on the physical properties of natural rubber composites

AbstractConducting elastomers are highly desirable in the present world because of their major applications in the electronic industry. Conductive carbon black (CCB) is a conventional reinforcing filler commonly used in elastomers to modify the mechanical as well as electrical properties. The present study focuses on the experimental and theoretical computation of filler reinforcement, dielectric, mechanical, dynamic mechanical, and surface morphology of natural rubber (NR)/CCB composites. Two step processing method is adopted to attain homogeneous dispersion of filler in the matrix: preparation of NR/CCB masterbatch through melt mixing using internal mixer followed by compounding in a two‐ roll mill. Improved DC conductivity in the order of 10−6 was obtained at higher filler loading indicating the formation of a continuous conductive network in the matrix. Percolation threshold was computed using Power law equation and obtained a value of 0.154 vol%. Theoretical predictions of mechanical modulus and tensile strength were done using rule of mixtures, Einstein, Guth and Kerner models and Nicolais‐Narkis and Kuneri‐Geil models respectively. A remarkable change in tensile strength is observed for NR as a function of the weight percentage of CCB; it is increased to 26.3 ± 0.9 MPa at 20 phr CCB from 17.1 ± 0.9 MPa for NR.

Electromagnetic Absorption and Mechanical Properties of Natural Rubber Composites Based on Conductive Carbon Black and Fe3O4.

In contemporary civilization, the electromagnetic radiation from electronic devices and communication systems has become a substantial pollutant. High-performance electromagnetic absorbers have become a solution for absorbing unwanted electromagnetic waves. This research proposed a lightweight and flexible electromagnetic absorber produced from natural rubber filled with conductive carbon black (CCB) and Fe3O4. The effect of CCB, Fe3O4, and a combination of CCB and Fe3O4 as a hybrid filler on foam morpholog, electromagnetic reflectivity, tensile strength, and compression set properties were investigated. In addition, the effect of the alternating layered structure of CCB and Fe3O4 on electromagnetic absorption was investigated. The results indicated that the composite foam exhibited an interconnected network structure that enhanced the electromagnetic attenuation in the absorber. CCB increased the electromagnetic absorption of the foam, whereas Fe3O4 had less of an effect. The foam filled with the hybrid filler at the CCB/Fe3O4 ratio of 8/2 exhibited excellent electromagnetic absorption. The composite foam had a higher tensile modulus and higher strength compared to neat foam. The addition of CCB decreased the compression set; however, the compression set was improved by the incorporation of Fe3O4. Composite foams filled with hybrid filler can serve as highly efficient electromagnetic absorbing materials.

Comparative study on the effect of carbon nanotubes and carbon black on fatigue properties of natural rubber composites

Fatigue property is of great importance for the security and reliability of rubber products. The fatigue performance of natural rubber (NR) filled with carbon nanotube (CNT) and carbon black (CB) with different content but similar hardness was investigated. Results indicated that CNT/NR exhibited the best fatigue performance at low CNT content and fatigue strain, while the crack growth was accelerated with the increase of CNT content and strain. As for CB/NR, the fatigue resistance increased with CB content and strain. The different fatigue performance of NR composites was discussed from the perspective of hysteresis, strain-induced crystallization, and stress concentration effect.

STUDIES ON THE THERMODYNAMIC PROPERTIES OF NATURAL RUBBER COMPOSITES FILLED WITH CLAY AND CORN COB

The mechanical properties of materials such as natural rubber composites determine their usefulness as engineering or biological materials. The thermodynamic properties of natural rubber composites filled with clay and corn cob at varying volume fraction of filler were studied with a view of relating and comparing thermodynamic parameters (ΔG, ΔH and ΔS) to mechanical properties (Young’s modulus, tensile strength, elongation at break, etc) of natural rubber composites. The rubber composites were prepared using a standard compounding recipe. The tension observed for each rubber composite as a result of changes in temperature was used in evaluating thermodynamic parameters via Arrhenius equation and plot. These properties have been evaluated by measuring the thermodynamic parameters of natural rubber composites compounded with varying percent volume fractions (5% - 25%) of two fillers- clay and corn cob. The results indicated that the maximum values of ΔG and ΔH was obtained for corn cob filled composites at 10% volume fraction, while the optimal values of ΔS for the same composites was found to be at 5% and 25% volume fraction. At lower filler concentration (5 – 17.5%), corn cob filled composites were observed to have higher modulus than clay filled rubber composites, while at these concentration ranges, clay was found to impact higher tensile strength to natural rubber than corn cob filler.