Carbon Black in NR/BR Blends for Truck Tires

1985 ◽  
Vol 58 (2) ◽  
pp. 350-382 ◽  
Author(s):  
W. M. Hess ◽  
P. C. Vegvari ◽  
R. A. Swor
Keyword(s):  
Fatigue Life ◽  
Carbon Black ◽  
Phase Distribution ◽  
Dynamic Properties ◽  
Performance Criteria ◽  
Polymer Phase ◽  
Tear Strength ◽  
Truck Tires ◽  
Bound Rubber ◽  
Heat Buildup

Abstract A series of ten commercial tread-grade carbon blacks were evaluated in a 60/40 NR/BR truck tire tread formulation. A number of important physical properties and performance criteria were assessed in terms of carbon black surface area and DBPA. Significant response equations were obtained for viscosity, bound rubber, resilience, heat buildup, tear strength, and dynamic properties. Dynamic modulus showed a much greater dependence on DBPA in comparison to previous studies on SBR/BR compounds. In a second designed experiment, a single carbon black (N299) was studied as a function of the NR/BR ratio and the amount of carbon black added to the BR phase. The BR black loading was varied at 30, 60, and 90 phr using separate masterbatches which were blended with NR-black masterbatches to give the same final composition for all of the compounds. Properties such as resilience, heat buildup, fatigue life, and tear strength were all improved in the direction of higher loadings of carbon black in the NR phase. A high loading of black in the BR phase caused low bound-rubber development and poor dispersion. This was found to be related to the viscosity ratio of the separate masterbatches. NR to BR viscosity ratios of about 1 to 3 produced good dispersion and high bound rubber. When the BR masterbatch viscosity was two to three times higher than the NR masterbatch, however, dispersion and bound-rubber development dropped sharply at the same total mixing energy. Low hysteresis properties were found to be most dependent on high bound-rubber development, with polymer phase distribution having a relatively minor influence. In contrast, tear strength and fatigue life reached their maximum levels when the NR was the more continuous polymer phase. High bound rubber also appears to enhance tear strength and fatigue life by improving the microdispersion of the carbon black.

Elastomer Blend Properties—Influence of Carbon Black Type and Location

1977 ◽  
Vol 50 (2) ◽  
pp. 301-326 ◽  
Author(s):  
W. M. Hess ◽  
V. E. Chirico
Keyword(s):  
Fatigue Life ◽  
Carbon Black ◽  
Wide Distribution ◽  
Continuous Phase ◽  
Unit Size ◽  
Polymer Phase ◽  
Tear Strength ◽  
Lower Heat ◽  
Heat Buildup ◽  
Tear Resistance

Abstract Criteria for minimizing hysteresis in carbon-black-filled elastomer blends are: (1) large black unit size, wide distribution, and low structure; (2) higher black loading in the discrete polymer phase (large zones); and (3) polymer of lower hysteresis as the continuous phase (low black loading). Of the different strength properties that were evaluated, tear and fatigue resistance showed the greatest dependence on black location in NR-BR and NR-SBR blends. Both properties were markedly higher for NR-BR, with most of the black in the NR phase. In NR-SBR, tear strength was higher with high loadings of black in the SBR. Fatigue life showed a reverse pattern, but the variations were not as great in this system. Criteria for maximizing tear resistance are: (1) small black unit size, low structure; (2) higher loading of carbon black in the continuous polymer phase ; and (3) the polymer of higher strength as the continuous phase. There may also be optimum levels of polymer zone size and black size distribution which affect tear strength. Optimized performance in a 50:50 NR-BR radial truck tire tread stock was obtained with a wide-distribution N-375 (50:50 N-351-N-110 blend) black with 75% location in the NR phase. This black gave 5–6°C lower heat buildup, equivalent modulus, 35% higher tear strength, and almost double the fatigue life of a conventionally mixed N-220 at essentially equivalent tread wear resistance (−4%). Optimized performance in 50:50 NR-SBR was indicated for a wide-distribution N-231 type (50:50 blend of N-351-N-119) with 75% of the black in the SBR phase. In comparison to conventionally mixed N-234 and N-220, this black gave about 8–10°C lower heat buildup, about 15% lower modulus, and essentially equal tensile, tear, and fatigue properties. Alternatively, a standard N-231 type with 75% location in the NR phase showed about 5–6°C lower heat buildup, about 20% lower modulus, equivalent tensile strength, 60% higher tear resistance, and 75–120% higher fatigue life.

scholarly journals The Effects of Silica/Carbon Black Ratio on the Dynamic Properties of the Tread compounds in Truck Tires

2012 ◽  
Vol 9 (3) ◽  
pp. 1102-1112 ◽  
Author(s):  
Ramin Zafarmehrabian ◽  
Saeed Taghvaei Gangali ◽  
Mir Hamid Reza Ghoreishy ◽  
Mehran Davallu
Keyword(s):  
Carbon Black ◽  
Dynamic Properties ◽  
Rolling Resistance ◽  
Major Constituent ◽  
Rubber Compound ◽  
Precipitated Silica ◽  
Truck Tires ◽  
Wet Grip ◽  
Heat Buildup ◽  
Reinforcing Filler

NR is the major constituent in the rubber compound used for the tread on the truck tires. A general compound formulation of the tire tread includes NR and BR as polymer base and carbon black as the reinforcing filler, and curative components. In this paper the effects of dual filler system (carbon black and precipitated silica) on the dynamic properties of tire treat has been studied. The results show by increasing of precipitated silica, significant improvement was observed in fatigue resistance, rolling resistance and heat buildup of the tire. Tensile strength and modulus and wet grip of tire tread decrease with increasing of silica in rubber compound formulation.

PROPERTIES OF SBR FILLED WITH CARBON BLACK AND ARAMID PULP HYBRID FILLER: COMPARISON BETWEEN PREDISPERSED ARAMID PULP AND CONVENTIONAL ARAMID PULP

2016 ◽  
Vol 89 (4) ◽  
pp. 640-652 ◽  
Author(s):  
Manuchet Nillawong ◽  
Pongdhorn Sae-oui ◽  
Krisda Suchiva ◽  
Chakrit Sirisinha
Keyword(s):  
Carbon Black ◽  
Hybrid Composites ◽  
Aramid Fiber ◽  
Rubber Content ◽  
Hybrid Filler ◽  
Fiber Loading ◽  
Bound Rubber ◽  
Extended Range ◽  
Heat Buildup ◽  
Rubber Filler

ABSTRACT Compounds of SBR incorporated with hybrid filler of carbon black (CB) and aramid pulp were prepared. The ratio of CB to aramid pulp was varied and its effects on viscoelastic and mechanical properties of the rubber were investigated. Two aramid pulp types were used in this study: conventional aramid pulp (CAP) and the predispersed aramid pulp (PAP). The rubber–filler interaction as indicated by bound rubber content decreases with increasing aramid pulp loading, regardless of the aramid pulp type. This results in a decrease in tensile and abrasion properties with increasing fiber loading. The energy dissipation properties of the hybrid composites are also poorer than those of the CB/SBR composite, as reflected by the heat buildup values. Use of predispersed aramid fiber resulted in improved dispersion of the fiber in SBR. Thus, Mooney viscosities of the PAP-filled systems are lower than those of the CAP-filled systems, but the percentages of elongation at breaks are higher. The distinct feature of aramid fiber/CB hybrid SBR composites is their high moduli over an extended range of temperatures up to 80°C that is unattainable with the use of CB alone.

scholarly journals Mechanical properties and dissipation energy of carbon black/rubber composites

2021 ◽  
Vol 30 ◽  
pp. 263498332110054
Author(s):  
Rungsima Chollakup ◽  
Supitta Suethao ◽  
Potjanart Suwanruji ◽  
Jirachaya Boonyarit ◽  
Wirasak Smitthipong
Keyword(s):  
Mechanical Properties ◽  
Carbon Black ◽  
Rolling Resistance ◽  
Mechanical Analysis ◽  
Rubber Composites ◽  
Dissipation Energy ◽  
Truck Tires ◽  
Reinforcing Agent ◽  
Bound Rubber ◽  
Heat Build Up

The effects of carbon black on the properties of rubber composites were studied in order to explore their value in producing low rolling resistance truck tires. Carbon black with different grades, N330 (coarser grade of 26–30 nm) and N220 (finer grade of 20–25 nm), was used as a reinforcing agent of natural rubber. The effects of different ratios of carbon black N330 at 40, 45, 50 and 55 parts per hundred rubber (phr) and N220 at 30, 35, 40 and 50 phr were investigated. Rubber composites with N220 had greater rubber/carbon black interaction than those with N330. The Mooney viscosity of rubber composite increased when the carbon black ratio increased. After vulcanisation of rubber, the samples were characterised by dynamic mechanical analysis, tensile strength and heat build-up. The results showed that the strength of rubber composites increased with increasing carbon black ratios. Interestingly, at the same bound rubber level, rubber composites with N220 presented lower dissipation energy, heat build-up and better mechanical properties than those with N330. This study indicated that reinforcement with an optimum amount of carbon black N220 would improve several desirable characteristics of rubber composites when used in low rolling resistance truck tires.

EFFECTS OF BLEND RATIO AND SBR TYPE ON PROPERTIES OF SILICA-FILLED SBR/NR TIRE TREAD COMPOUNDS

2016 ◽  
Vol 89 (2) ◽  
pp. 240-250 ◽  
Author(s):  
Pongdhorn Sae-oui ◽  
Krisda Suchiva ◽  
Uthai Thepsuwan ◽  
Wenussarin Intiya ◽  
Pram Yodjun ◽  
...  
Keyword(s):  
Dynamic Properties ◽  
Rolling Resistance ◽  
Skid Resistance ◽  
Blend Ratio ◽  
Elongation At Break ◽  
Tear Strength ◽  
Cure Time ◽  
Lower Heat ◽  
Heat Buildup ◽  
Wet Skid Resistance

ABSTRACT The influences of blend ratio between SBR and NR and SBR type, emulsion SBR (E-SBR) and solution SBR (S-SBR), on properties of silica-filled passenger car tire tread–based compounds were investigated. Results reveal that, with increasing NR proportion, cure time and most mechanical and dynamic properties, for example, tensile strength, tear strength, modulus, abrasion resistance, and wet skid resistance of the compounds and vulcanizates, are reduced, whereas the improvements in elongation at break and crack growth resistance are observed. The unexpectedly impaired mechanical and dynamic properties identified in the presence of NR are mainly caused by thermal degradation of NR taking place during the mixing process at high temperature. Compared with E-SBR, S-SBR provides superior properties in many aspects, that is, higher modulus and greater abrasion and wet skid resistances as well as lower heat buildup and rolling resistance. However, E-SBR gives greater tear strength than S-SBR.

Measurement of Carbon Black Dispersion in Rubber by Surface Analysis

1978 ◽  
Vol 51 (4) ◽  
pp. 817-839 ◽  
Author(s):  
P. C. Vegvari ◽  
W. M. Hess ◽  
V. E. Chirico
Keyword(s):  
Surface Roughness ◽  
Tensile Strength ◽  
Fatigue Life ◽  
Carbon Black ◽  
Distinct Advantage ◽  
Dispersion Index ◽  
Programmable Calculator ◽  
Wide Range ◽  
Heat Buildup ◽  
Carbon Black Dispersion

Abstract A stylus-type surface roughness tester has been applied to the study of carbon black dispersion in a number of different rubber systems. The method is based on a freshly cut rubber surface which is tracked by the stylus to provide a roughness trace on a strip chart. Carbon black agglomerates deflect the cut path because of their higher hardness relative to the surrounding matrix. Thus, surface roughness diminishes at increasing levels of dispersion. A quantitative index of dispersion quality may be derived from the frequency and average height of the roughness peaks. The method offers a distinct advantage over previous methods in its ability to provide precise dispersion ratings over a very wide range of rubber processing levels from the masterbatch to the final product. The technique is applicable to the analysis of unvulcanized rubber compounds and could be utilized as a factory quality control procedure. Direct interfacing of the surface analyzer to a programmable calculator would provide quantitative dispersion ratings within five minutes of the receipt of a sample. Studies of varied carbon black dispersions in SBR and SBR/BR passenger tread formulations have confirmed the work of previous authors. Tensile strength, fatigue life, resilience, elongation, and extrusion shrinkage increased at higher dispersion levels, while Mooney viscosity, Shore hardness and heat buildup exhibited a progressive decrease. The properties of a 50/50 NR/BR truck tread formulation showed a more varied response to black dispersion. Tensile strength and resilience showed considerably less dispersion dependence than SBR and SBR/BR. However, the tensile response increases with increasing black fineness and decreasing structure, while resilience showed the opposite trend. Fatigue life and heat buildup showed the same trends observed for SBR and SBR/BR. However, NR/BR treadwear (radial tires) showed considerably less dependence on dispersion above the 70% level, in comparison to those other polymers (bias ply tires). NR/BR with N220 at a dispersion index of 68 gave treadwear resistance that was equivalent to the same compound at a dispersion index of 89. However, dispersion indices of 50 or lower caused severely depressed treadwear resistance for the different blacks that were tested. The milling of NR/BR masterbatches cooled overnight produced significantly higher dispersion levels in comparison to hot batches at the same total mixing energy. This procedure can be employed to optimize treadwear and other properties at lower levels of energy consumption.

Characterization of Immiscible Elastomer Blends

1993 ◽  
Vol 66 (3) ◽  
pp. 329-375 ◽  
Author(s):  
W. M. Hess ◽  
C. R. Herd ◽  
P. C. Vegvari
Keyword(s):  
Carbon Black ◽  
Phase Distribution ◽  
Domain Size ◽  
Carbon Black Particle ◽  
Quantitative Information ◽  
Equal Distribution ◽  
Tear Strength ◽  
Carbon Blacks ◽  
Vulcanized Rubber ◽  
Heat History

Abstract Considerable improvements have been made in the analysis of elastomer blends for composition, morphology and filler inter-phase distribution. GC, IR, NMR and thermal analysis (DTG, DSC, TG) techniques can provide quantitative information on composition. The latter three methods, along with SAXS, SANS, DMTA and microscopy (LM phase contrast, TEM, SEM, AFM) are also useful for resolving differences in blend homogeneity. The microscopical techniques are the most useful for characterizing morphology. TEM, in conjunction with cryosectioning and staining techniques, has provided the best means of resolving filler distribution to date. However, new AFM scanning modes may provide improved analyses in the future. Carbon black inter-phase distribution in blends of NR, SBR and BR can be controlled reasonably well by blending Banbury mixed masterbatches containing the desired carbon black loading in each polymer. Transfer of carbon black from one elastomer to another is favored by low unsaturation for the polymer originally containing the black, or a low heat history (e.g. solution and latex mixing) during preparation of the masterbatch. The overall polymer interaction with carbon black increases in the order: IIR, EPDM, NR, BR, SBR, the latter two being fairly close. Commercial carbon blacks will transfer extensively from an IIR Banbury masterbatch to NR, but not from EPDM to NR. Significant transfer to SBR occurs from both IIR and EPDM. Inert (partially graphitized) carbon blacks tend to distribute more evenly between the blend components regardless of which polymer contained them initially. Carbon black phase distributional variations can cause significant changes in unvulcanized and vulcanized rubber properties. For NR/BR and NR/SBR blends, reduced hysteresis generally occurs with a higher carbon black loading in the NR phase. Tear strength and cut growth tend to be maximized with higher carbon black in the continuous polymer phase, particularly when that phase is the higher strength polymer. The smaller the carbon black particle size, the greater the improvement in tear strength as a function of phase distribution. NR/BR fatigue life was maximized with about an equal distribution of carbon black in each polymer. This type of carbon black distribution also produced the greatest resistance to ozone cracking for NR/EPDM blends, which were further improved with very small domain size for the EPDM (disperse) phase. The abrasion resistance of NR/BR blends has indicated some improvement in the direction of higher carbon black in the BR. These results have been variable, however, and further study is needed for clarification.

Influence of graphene oxide and multiwalled carbon nanotubes on the dynamic mechanical properties and heat buildup of natural rubber/carbon black composites

2017 ◽  
Vol 50 (5) ◽  
pp. 403-418 ◽  
Author(s):  
H Zhang ◽  
YT Wei ◽  
ZR Kang ◽  
GZ Zhao ◽  
YQ Liu
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Graphene Oxide ◽  
Carbon Black ◽  
Natural Rubber ◽  
Multiwalled Carbon Nanotubes ◽  
Dynamic Properties ◽  
Multiwalled Carbon ◽  
Stirring Time ◽  
Heat Buildup

In this study, graphene oxide (GO) and multiwalled carbon nanotubes (MWNTs) were incorporated into natural rubber (NR) to study the influence of each of these materials when substituted for carbon black (CB) on the structure and properties of NR/CB composites. The influence of stirring time on the composites used to prepare the masterbatch was also studied. Morphological observations revealed that the dispersion of the filler was improved by partially substituting GO and MWNTs for CB. Improvements in the static mechanical properties and dynamic properties were achieved when the concentration of GO or MWNTs was 1 phr. The highest modulus and hardness was found in the composites with a short stirring time used for the preparation of the masterbatch. When compared to CB-filled vulcanizates, composites with GO had a greater tensile strength and equivalent heat buildup, which is mainly attributed to the larger cross-link density. In this article, compared with the MWNTs, GO is more beneficial to the preparation of rubber composite with high mechanical properties and low heat buildup. This is mainly due to the common functional groups carboxyl, hydroxyl, and epoxide in the GO can improve the dispersion of GO within a matrix.

INFLUENCE OF FILLERS ON SEMI-EFFICIENT VULCANIZED NATURAL RUBBER: DYNAMIC PROPERTIES AND HEAT BUILDUP

2015 ◽  
Vol 88 (3) ◽  
pp. 412-420 ◽  
Author(s):  
Huan Zhang ◽  
Zhiyi Zhang ◽  
Guizhe Zhao ◽  
Yaqing Liu ◽  
Ye Li ◽  
...  
Keyword(s):  
Particle Size ◽  
Carbon Black ◽  
Natural Rubber ◽  
Dynamic Properties ◽  
Carbon Black Particle ◽  
Reinforcing Fillers ◽  
Link Density ◽  
Black Particle ◽  
Tan Δ ◽  
Heat Buildup

ABSTRACT Carbon black and silica have long been recognized as reinforcing fillers, but their effect on the dynamic properties and heat buildup of vulcanizates is rarely reported. Therefore, natural rubber composites filled by carbon black with different particle size and silica were prepared. The Payne effect and heat buildup progressively decrease with an increase of carbon black particle size because of weaker filler network structure and better dispersion, the N754 filled sample in particular shows the lowest value, only 4.7 °C. The tensile strength and tear strength of composites all increase with the reducing carbon black particle size. SiO2-filled composites exhibit obvious Payne effects and inferior mechanical properties; at high strains (>10%), tan δ of SiO2-filled composites surpasses all that of carbon black–filled composites, due to the surface silanol groups on the silica surface and due to the decreased cross-link density.

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