Effect of Cohesion Loss Factor on Wet Skid Resistance of Tread Rubber

1998 ◽  
Vol 26 (4) ◽  
pp. 258-276 ◽  
Author(s):  
H. Takino ◽  
N. Isobe ◽  
H. Tobori ◽  
S. Kohjiya

Abstract The effect of cohesion loss factor on wet skid resistance has not been studied systematically using three major factors, i.e., adhesion, hysteresis, and cohesion. Two different abrasions, PICO and BPST, as the cohesion loss factor were investigated for different polymers, carbon black grades, and carbon black/oil loadings. These two abrasion mechanisms are quite different, and BPST abrasion was concluded to be more suitable as a cohesion loss factor for the BPST (wsn) and tire wet μa. From the difference between PICO and BPST abrasions, superior material factors were analyzed from the viewpoint of the compatibility of both abrasion life and wet skid resistance of tire.

2018 ◽  
Vol 43 (1) ◽  
pp. 81-89 ◽  
Author(s):  
J. Wu ◽  
C. Zhang ◽  
Y. Wang ◽  
B. Su ◽  
B. Gond

1987 ◽  
Vol 60 (4) ◽  
pp. 606-617 ◽  
Author(s):  
Luis González Hernández ◽  
Luis M. Ibarra Rueda ◽  
Celia Chamorro Antón

Abstract The natural magnesium silicate, sepiolite (trade name Pansil), can partially substitute (up to 30%) for carbon black without important losses in physical properties and occasionally can improve them. In the NR-based compounds, as the substitution takes place, vulcanization times and Mooney viscosities decrease. Tear and abrasion resistances are lower. The same effects are observed in the SBR-based compounds, though in this case, the addition of a silane coupling agent (Silane A-189) counteracts the negative effects of the sepiolite, and the obtained values are clearly better than those with only carbon black. According to tan δ behavior in truck tire tread compounds, this filler type gives a higher wet grip resistance, but rolling resistance would be adversely affected by its use, though the presence of a silane coupling agent diminishes these effects. On the contrary, in passenger tire tread compounds, the partial substitution for carbon black seems to increase the wet resistance too, without a pronounced damage in rolling resistance. In this case, the addition of the silane coupling agent produces an increase in wet skid resistance and a decrease in rolling resistance. Based on laboratory tests, rolling resistance increases in all cases, mainly when the sepiolite was modified with silane. Wet skid resistance showed no variations. Clearly, it would be desirable to confirm our observations by an actual tire test.


1968 ◽  
Vol 41 (4) ◽  
pp. 832-842 ◽  
Author(s):  
E. M. Bevilacqua ◽  
E. P. Percarpio

Abstract This review introduces a series of reports on a quantitative study of friction of rubber on wet surfaces. It was derived from concern over safety aspects of skidding on wet roads; this first paper deals with the relation between safety and traction. Subsequent papers deal with: A quantitative approach to characterization of road surfaces, identification of the surface features of importance, and estimation of their relative contributions to lubricated friction. Quantitative estimates of effects of properties of rubber materials on lubricated friction and an analysis of their relative importance in interaction with the significant features of the road surface. A quantitative basis for evaluation of wet skid resistance of roads, the choice of the rubber to be used in this evaluation, and methods of testing. An improved technique to measure the property of tread rubber important for wet skid resistance of tires. Identification and interpretation of the nature of friction on ice at low temperatures.


2021 ◽  
Vol 11 (21) ◽  
pp. 9834
Author(s):  
Indriasari Indriasari ◽  
Jacques Noordermeer ◽  
Wilma Dierkes

This study focuses on the use of oligomeric hydrocarbon resins in order to benefit from their effect on improving the performance of aircraft tire retreads. The aim was to enhance the tackiness for the retreading process and their final performance in terms of superior stress–strain properties and low heat generation in order to decrease treadwear; thus, increasing the tire’s service life, and in terms of traction or skid resistance to improve safety during landing of an aircraft. Two types of resins are investigated: a terpene phenol and an aromatic hydrocarbon C9 resin, added to compounds with different filler systems: Carbon Black (CB), hybrid Carbon Black/Silica (CB/SI), and pure Silica (SI). The rubber compounds and vulcanizates are compared to their controls for each filler system. The use of resins improves processing independent of the filler system, with a slight improvement of tensile strength, Modulus at 300% (M300%) and Elongation at Break (EAB). The incorporation of resins improves the tackiness for the compounds with all filler systems, which is beneficial for the retreading process. A significant improvement in Ice Traction (ICT) and Wet Skid Resistance (WSR) with a trade-off in Heat Build-Up (HBU) is observed in CB- and CB/SI-reinforced compounds when resins are added. Terpene phenol and aromatic hydrocarbon C9 resin show comparable ICT, while the aromatic hydrocarbon C9 resin gives a better WSR performance than the terpene phenol in all compounds. However, a slight improvement in HBU with the use of both resins is only observed in the SI-filled system. The present exploratory study into the addition of resins demonstrates the potential to significantly improve the overall performance of aircraft tire retreads, justifying more in-depth investigations into this possibility in real tires.


1998 ◽  
Vol 26 (4) ◽  
pp. 241-257 ◽  
Author(s):  
H. Takino ◽  
H. Takahashi ◽  
K. Yamano ◽  
S. Kohjiya

Abstract Wet skid resistance for rubbers with a wide range of carbon black loadings and process oil loadings was investigated from the viewpoints of viscoelastic properties and abrasion properties. An analysis of wet skid resistance by the factors of Tα and BPST abrasion, which was effectively performed on a wide range of polymers in a previous report, gave a poor correlation this time. In the case of a wide range of carbon black loadings and oil loadings, the factors of tan δ and BPST abrasion had a good relationship with wet skid resistance. In this study, tan δ at 7°C was found to be a suitable factor corresponding to adhesion loss and hysteresis loss in rubber friction. By the evaluation of abrasions, BPST abrasion and PICO abrasion were estimated to be governed by different mechanisms.


2008 ◽  
Vol 81 (4) ◽  
pp. 576-599 ◽  
Author(s):  
Meng-Jiao Wang ◽  
Yakov Kutsovsky

Abstract It was demonstrated previously that on the worn surface of vulcanizates during wet skid tests, carbon black is covered by rubber whereas silica particles are at least partly exposed. In this report, the experimental results of the effects of carbon black and silica on wet skid resistance measured by various test methods and under different conditions are explained based on the “Three Zone Concept” of the contact area of tread compounds with the track surface during sliding or rolling. The three zones are water film squeezing, transition and traction zones. In the first two zones, where hydro-dynamic and micro-elastohydrodynamic lubrication mechanisms are dominant, silica is beneficial for wet friction. In the traction zone, where friction is governed by boundary lubrication, carbon black is preferred. Under test conditions where the water squeezing and transition zones are more developed, such as at high speed, lower temperature, smoother track surface, lower load, higher slip angle, and ABS brake, the silica shows better performance, but otherwise where the traction zone is larger, carbon black gives higher wet skid resistance. Accordingly, a new carbon-silica dual phase filler CSDPF 4210 that is characterized by high surface coverage with silica has been developed. With this material, the wet skid resistance of a passenger tire on a car with ABS at high speed and smooth road surface is significantly improved.


1968 ◽  
Vol 41 (4) ◽  
pp. 881-889
Author(s):  
E. P. Percarpio ◽  
E. M. Bevilacqua

Abstract An important conclusion from Part V of this series is that the wet skid resistance of a tire tread rubber is almost completely determined by its resilience and hardness, resilience being the more important variable. A useful feature of this relation is that both measurements are nondestructive and can be made, in principle, on a finished tire. Hardness is easily measured with commercially available instruments, such as the Shore Durometer, but a comparably useful instrument, one portable and suitable for use to measure resilience of finished and mounted tires, was not available. We have made and used such an instrument and have found additionally that it has features which make it useful for other purposes, notably measurement of resilience of very thin rubber specimens.


2008 ◽  
Vol 81 (4) ◽  
pp. 552-575 ◽  
Author(s):  
Meng-Jiao Wang ◽  
Yakov Kutsovsky

Abstract From results of testing materials using a new filler, it was recognized that the wet skid resistance of tires is determined not only by dynamic properties of the tread compounds, but also by elastohydrodynamic lubrication, especially on the micro scale. By reviewing the basic concepts of friction under dry and wet conditions, and friction coefficients of possible model materials that are at the worn surface of tire tread compounds and road surface, it is inferred that after skid testing under wet conditions, the top skin of the worn surface contains some bare silica for silica-filled compounds, but the carbon black aggregates remain covered by rubber film. This inference is supported by measuring the surface energies of the fillers, analyzing the properties of filled vulcanizates, and direct investigation of worn surface of the compounds after skid test by AFM. The different surface compositions between silica- and carbon black-filled vulcanizates would lead to different effects on micro-elastohydrodynamic lubrication, hence wet skid resistance, which will be the topic of next report of this study.


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