Influence of Fillers Surface Characteristics on Bound Rubber Properties of Filled Natural Rubber Compounds

2013 ◽  
Vol 845 ◽  
pp. 412-416 ◽  
Author(s):  
Mustafa Kamal Mazlina

One of the most important phenomena in rubber science is the reinforcement by rigid entities, such as carbon black, clays, silicates and calcium carbonate. Thus, these fillers are added to rubber formulations to optimise properties that meet a given service application or set of performance parameters. Fillers can be divided into three categories reinforcing, semi-reinforcing and non-reinforcing. For a given elastomer and state of mix, bound rubber can be considered as a measurement of a surface activity of a filler and is considered as one of major factors in reinforcement. A strong rubber: filler interaction results in a large bound rubber content. Good dispersions and distribution of filler aggregates is also important for the full reinforcing potential of fillers to be reached. In this study, the influence of fillers on bound rubber content of Natural Rubber compounds were determined and compared. Results showed that the bound rubber content followed the trend of Carbon Black>Silica>Carbon Black>Starch. The two main filler characteristics that affect the bound rubber properties are the filler particle size and surface activity. The specific activity of the filler is determined by the physical and chemical nature of the filler surface in relation to that of elastomer. Keywords: reinforcement, surface energy

2017 ◽  
Vol 90 (4) ◽  
pp. 651-666 ◽  
Author(s):  
C. Hayichelaeh ◽  
L. A. E. M. Reuvekamp ◽  
W. K. Dierkes ◽  
A. Blume ◽  
J. W. M. Noordermeer ◽  
...  

ABSTRACT Diphenyl guanidine (DPG) is the most commonly used secondary accelerator in silica-reinforced rubber compounds because of its additional positive effect on the silanization reaction and deactivation of free silanol groups that are left over after the silanization. However, because of health and safety concerns about the use of DPG, which decomposes to give highly toxic aniline during high processing temperature, safe alternatives are required. This work investigates the effect of various types of aliphatic amines having alkyl or cyclic structures and similar pKa (i.e., hexylamine [HEX], decylamine [DEC], octadecylamine [OCT], cyclohexylamine [CYC], dicyclohexylamine [DIC], and quinuclidine [QUI]) on the properties of silica-reinforced natural rubber (NR) compounds by taking the ones with DPG and without amine as references. When compared with the compound without amine, the use of all amine types reduces filler–filler interaction (i.e., the Payne effect) and enhances filler–rubber interaction, as indicated by bound rubber content and decreased heat capacity increment. The amines with alkyl chains can reduce the Payne effect and enhance cure rate to a greater extent compared with the amines with cyclic rings as a result of better accessibility toward the silica surface and a shielding effect because of less steric hindrance. The longer carbon tails on linear aliphatic amines ranging from HEX, DEC, to OCT lead to a lower Payne effect, lower heat capacity increment, higher bound rubber content, and higher modulus as well as tensile strength. Overall, the use of OCT provides silica-reinforced NR compounds with properties closest to the reference one with DPG and can act as a potential alternative for DPG.


2012 ◽  
Vol 501 ◽  
pp. 3-7
Author(s):  
Abu Bakar Rohani ◽  
Mustafa Kamal Mazlina ◽  
Fauzi Mohd Som

Natural rubber-grafted-poly(methyl methacrylate) containing 30 and 50 percent of methyl methacrylate (MMA) monomer per 100 parts by weight of the dry rubber content denoted as NR-g-PMMA 30 and NR-g-PMMA 50, respectively were prepared via emulsion polymerisation technique. The occurrences of graft copolymerisation of PMMA onto NR were confirmed by proton Nuclear Magnetic Resonance (1H NMR) and Fourier Transform Infrared (FTIR) following purifications. The reinforcement of rubber by fillers is of great practical and technical importance. Thus, these fillers are added to rubber formulations to optimize the properties to meet a given application or set of performance parameters. In this study, the effect of carbon black in NR-g-PMMA 30 and NR-g-PMMA 50 rubber compounds were evaluated. Our results demonstrated that tensile strength, elongation at break and compression set reduced, while the hardness and solvent resistance increased in the presence of carbon black filler in comparison to the unfilled compound.


2015 ◽  
Vol 88 (2) ◽  
pp. 289-309 ◽  
Author(s):  
Sunita Mohapatra ◽  
Golok Bihari Nando

ABSTRACT Carbon black is advantageous for rubber as a reinforcing filler. Carbon blacks at higher loadings require process aids for easier processing and improved filler dispersion. Aromatic oils have been used so far in the rubber industry as plasticizer and process aids. The presence of polycyclic aromatic hydrocarbons in these oils has raised concerns, and they have been banned. Rubber industries are looking for alternate sources of process aids from renewable resources. Cardanol (m-pentadecenyl phenol), an agricultural by-product of the cashew industry, is cheap and abundantly available. It was proved recently to be a plasticizer and a multifunctional additive. The dispersion of carbon black in natural rubber (NR) grafted chemically with cardanol (CGNR) is investigated and compared with that of oil plasticized natural rubber. The physico-mechanical properties of the carbon black–filled CGNR vulcanizates are better than that of the aromatic oil plasticized NR vulcanizates. The cross-link density and bound rubber content are higher and the Payne effect is lower for the carbon black–filled CGNR vulcanizates as compared with oil plasticized NR vulcanizates. Dispersion of carbon black in the CGNR matrix is uniform and better than the aromatic oil plasticized NR.


Author(s):  
Xuanyu Shi ◽  
Shihao Sun ◽  
An Zhao ◽  
Haimo Zhang ◽  
Min Zuo ◽  
...  

2017 ◽  
Vol 744 ◽  
pp. 282-287
Author(s):  
Sarawut Prasertsri ◽  
Sansanee Srichan

This research aimed to develop the formulation of natural rubber filled with carbon black, silica and calcium carbonate for rubber calf nipple application. The reverse engineering was performed on the calf nipple product to analyze the rubber type and component by using Soxhlet extraction, thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR) techniques. Furthermore, mechanical properties were examined to act as benchmark for the rubber compound design. The results showed that rubber component in the nipple product was natural rubber, whereas two filler types revealed as carbon black and calcium carbonate with 10 and 35 of the total weight. In addition, rubber nipple showed the hardness of 46±1 Shore A and tensile strength of 5.3±0.60 MPa. From the investigation of the properties of developed rubber compounds in this work, it was found that the mechanical properties depended on type and content of filler. The required mechanical properties of vulcanizates were achieved at 20 phr of carbon black (N330), 20 phr of silica and 120 phr of calcium carbonate.


2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
S. Sattayanurak ◽  
J. W. M. Noordermeer ◽  
K. Sahakaro ◽  
W. Kaewsakul ◽  
W. K. Dierkes ◽  
...  

Modern fuel-saving tire treads are commonly reinforced by silica due to the fact that this leads to lower rolling resistance and higher wet grip compared to carbon black-filled alternatives. The introduction of secondary fillers into the silica-reinforced tread compounds, often named hybrid fillers, may have the potential to improve tire performance further. In the present work, two secondary fillers organoclay nanofiller and N134 carbon black were added to silica-based natural rubber compounds at a proportion of silica/secondary filler of 45/10 phr. The compounds were prepared with variable mixing temperatures based on the mixing procedure commonly in use for silica-filled NR systems. The results of Mooney viscosity, Payne effect, cure behavior, and mechanical properties imply that the silica hydrophobation and coupling reaction of the silane coupling agent with silica and elastomer are significantly influenced by organoclay due to an effect of its modifier: an organic ammonium derivative. This has an effect on scorch safety and cure rate. The compounds where carbon black was added as a secondary filler do not show this behavior. They give inferior filler dispersion compared to the pure silica-filled compound, attributed to an inappropriate high mixing temperature and the high specific surface area of the carbon black used. The dynamic properties indicate that there is a potential to improve wet traction and rolling resistance of a tire tread when using organoclay as secondary filler, while the combination of carbon black in silica-filled NR does not change these properties.


Sign in / Sign up

Export Citation Format

Share Document