Simple Method for Determining the Dynamic Coefficient of Friction of Vulcanized Rubber

1951 ◽  
Vol 24 (2) ◽  
pp. 374-380
Author(s):  
B. B. S. T. Boonstra
Keyword(s):  
Carbon Black ◽  
Natural Rubber ◽  
Coefficient Of Friction ◽  
Simple Method ◽  
Rubber Powder ◽  
Vulcanized Rubber ◽  
Rubber Compounds ◽  
The Coefficient Of Friction ◽  
Rubber Concrete ◽  
Better Than

Abstract A method for measuring the coefficient of friction at low speeds by means of a normal dynamometer for rubber testing is described. To this end a couple of molded rubber wheels are pulled over a piece of roadlike surface. At the same time the wheels are forced to rotate with a speed nonconcordant with the linear speed on the surface, so that a certain amount of friction occurs. The force necessary to turn the wheels over the surface is recorded on the dynamometer; the average is proportional to the average coefficient of friction. Preliminary experiments were carried out to prove the usefulness of the apparatus. A number of compounds of natural rubber, GR-S, and “cold” rubber were tested on four surfaces: asphalt, asphalt with rubber, concrete, and ground glass. Although the apparatus allows variation of load and of speed, the experiments were carried out at a speed of 100 cm. per minute and only with a load of 4 kilograms. On dry surfaces, the highest coefficient of friction was found with a natural-rubber compound on an asphalt material in which rubber powder had been dispersed. With most rubbers this surface showed a somewhat higher coefficient of friction than did the asphalt without rubber-powder, which in turn was better than the other two surfaces. On the average there was little difference between the various rubber compounds, though natural rubber seemed to yield the highest values. Natural-rubber pure gum compound did not show higher values than the carbon black mixes, but a vulcanizate with cyclorubber instead of carbon black was definitely better.

ANALYSIS OF CARBON BLACK–REINFORCED CARDANOL-MODIFIED NATURAL RUBBER COMPOUNDS

2015 ◽  
Vol 88 (2) ◽  
pp. 289-309 ◽  
Author(s):  
Sunita Mohapatra ◽  
Golok Bihari Nando
Keyword(s):  
Carbon Black ◽  
Natural Rubber ◽  
Multifunctional Additive ◽  
Rubber Compounds ◽  
Bound Rubber ◽  
Link Density ◽  
Polycyclic Aromatic ◽  
Cross Link Density ◽  
Filler Dispersion ◽  
Better Than

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.

The Thermal Diffusivity and Conductivity of Natural Rubber Compounds

1977 ◽  
Vol 50 (2) ◽  
pp. 253-265 ◽  
Author(s):  
D. Hands ◽  
F. Horsfall
Keyword(s):  
Thermal Properties ◽  
Carbon Black ◽  
Natural Rubber ◽  
Small Area ◽  
Empirical Equations ◽  
Conductivity Measurements ◽  
Varying Thickness ◽  
New Methods ◽  
Rubber Compounds ◽  
Better Than

Abstract New methods of measuring the conductivity and diffusivity of rubbers from ambient to 250°C have been developed. The method of measuring diffusivity described in this paper is simple to use and very much quicker than previous methods, the whole temperature range being covered in about half an hour. The accuracy is about 5%. Two disk-shaped samples are used, 48 mm diameter and 2 mm thick, but the geometry can be changed to accommodate samples of varying thickness. The method is suitable for anisotropic samples but, because the measurement is made over a small area, they must be homogeneous. Diffusivity and conductivity measurements have been made on a series of carbon-black-loaded natural rubber compounds. Both thermal properties depend on temperature, type of rubber, and the type and quantity of carbon black. Empirical equations have been obtained relating diffusivity and conductivity to temperature and black loading. These fit the data to better than 10%.

Influence of carbon black on the Payne effect of filled natural rubber compounds

2020 ◽  
pp. 108586
Author(s):  
Xuanyu Shi ◽  
Shihao Sun ◽  
An Zhao ◽  
Haimo Zhang ◽  
Min Zuo ◽  
...  
Keyword(s):  
Carbon Black ◽  
Natural Rubber ◽  
Payne Effect ◽  
Rubber Compounds

Characterization of Snap-On Calf Nipple Product and Development of its Compound Formulation Based on Natural Rubber

2017 ◽  
Vol 744 ◽  
pp. 282-287
Author(s):  
Sarawut Prasertsri ◽  
Sansanee Srichan
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Calcium Carbonate ◽  
Carbon Black ◽  
Natural Rubber ◽  
Soxhlet Extraction ◽  
Rubber Compound ◽  
Rubber Compounds ◽  
Rubber Component

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.

scholarly journals Silica-Reinforced Natural Rubber: Synergistic Effects by Addition of Small Amounts of Secondary Fillers to Silica-Reinforced Natural Rubber Tire Tread Compounds

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
S. Sattayanurak ◽  
J. W. M. Noordermeer ◽  
K. Sahakaro ◽  
W. Kaewsakul ◽  
W. K. Dierkes ◽  
...  
Keyword(s):  
Carbon Black ◽  
Natural Rubber ◽  
Dynamic Properties ◽  
Synergistic Effects ◽  
Coupling Reaction ◽  
Rolling Resistance ◽  
High Specific Surface Area ◽  
Pure Silica ◽  
Rubber Compounds ◽  
Wet Grip

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