INTERPRETATION OF THE TANδ PEAK HEIGHT FOR PARTICLE-FILLED RUBBER AND POLYMER NANOCOMPOSITES WITH RELEVANCE TO TIRE TREAD PERFORMANCE BALANCE

ABSTRACT The aim of this research is to clarify the meaning of the peak height for the viscoelastic loss tangent (tanδ) in the glass transition region of particle-filled rubber, polymer nanocomposites, and polymer systems in general. Filler, oil, and curative loadings were systematically varied in a model styrene-butadiene rubber formulation with carbon black as the reinforcing filler. The dynamic mechanical responses of these compounds enabled a detailed study of the glass-to-rubber softening transition, which is known to play an important role with respect to the balance of traction, handling, and rolling resistance characteristics of tire treads. From the temperature-dependent viscoelastic results that were acquired at fixed frequency and small dynamic strain, it was demonstrated that a higher peak value for tanδ was correlated with a lower dynamic modulus in the rubbery state. Adjusting filler volume fraction was found to be an effective way of changing the rubbery modulus and hence the tanδ peak height. It was furthermore verified that such a correlation is a universal material-independent viscoelastic effect by mathematically producing a similar trend by varying the rubbery modulus parameter in the Havriliak–Negami viscoelastic model. This investigation also showed why glass transition temperature should be determined from the position of the loss modulus peak and not the tanδ peak. Cure behavior, tensile stress–strain properties, and extent of filler networking (Payne effect) for these rubber compounds will additionally be discussed.

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MULTIPLE GLASS TRANSITION TERPOLYMERS OF ISOPRENE, BUTADIENE, AND STYRENE

Rubber Chemistry and Technology ◽

10.5254/1.3512953 ◽

2010 ◽

Vol 83 (4) ◽

pp. 380-390 ◽

Cited By ~ 9

Author(s):

Adel F. Halasa ◽

Bill B. Gross ◽

Wen-Liang Hsu

Keyword(s):

Glass Transition ◽

Loss Modulus ◽

Rolling Resistance ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Transition Temperatures ◽

Wear Properties ◽

Glass Transition Temperatures ◽

The One ◽

Butadiene Styrene

Abstract Novel polymers that will contribute to a better combination of traction and tread wear in tire applications, which is historically difficult to achieve, have been developed. In this work, multiple viscoelastic polymers possessing multiple glass transition temperatures terpolymers of isoprene/butadiene/styrene were synthesized containing 45/45/10, 40/40/20, and 35/35/30 polymer ratios in 5-gallon laboratory reactors using tetramethylethylenediamine or bis(dipiperdino) ethane as a modifier. These polymers show two glass transition temperatures (Tg's); the one that occurs at higher temperatures (–25 to –10 °C) is known to contribute to good wet traction properties, while the lower Tg is known to contribute to better tread wear properties. These terpolymers were characterized by the fact that their multiviscoelastic loss modulus has narrow molecular distribution for better rolling resistance. In a standard ASTM D31912 carbon-black-filled tread compound recipe, the polymers having all three terpolymers of isoprene/butadiene/styrene polymerized showed excellent values of loss tangent at 0 and 60 ºC, which is a laboratory predictor for both wet traction and rolling resistance. These terpolymers when evaluated in the same ASTM D3191 delivered better properties in a tread compound recipe than either solution or emulsion styrene-butadiene rubber in a formulation that has natural rubber or polybutadiene.

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Pseudo-Elastic Analysis with Permanent Set in Carbon-Filled Rubber

Advances in Polymer Technology ◽

10.1155/2019/2369329 ◽

2019 ◽

Vol 2019 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

LiHong Huang ◽

Xiaoxiang Yang ◽

Jianhong Gao

Keyword(s):

Carbon Black ◽

Constitutive Model ◽

Residual Strain ◽

Volume Fraction ◽

Styrene Butadiene Rubber ◽

Uniaxial Tensile ◽

Butadiene Rubber ◽

Permanent Set ◽

Cyclic Loading And Unloading ◽

Filled Rubber

Via cyclic loading and unloading tests of natural/styrene-butadiene rubber (NSBR) blends at room temperature, the effects of the stretching, rate, temperature, and volume fraction of carbon black in the filled rubber on a permanent set (residual strain) were studied. The results showed that increasing the stretching, rate, and volume fraction of carbon black and reducing the temperature yielded greater residual strain. The uniaxial tensile behaviors of composites with the Mullins effect and residual strain were simulated using the ABAQUS software according to the aforementioned data. An Ogden-type constitutive model was derived, and the theory of pseudo-elasticity proposed by Ogden and Roxburgh was used in the model. It was found that the theory of pseudo-elasticity and the Ogden constitutive model are applicable to this composite, and if combined with plastic deformation, the models are more accurate for calculating the residual strain after unloading.

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FLOCCULATION, REINFORCEMENT, AND GLASS TRANSITION EFFECTS IN SILICA-FILLED STYRENE-BUTADIENE RUBBER

Rubber Chemistry and Technology ◽

10.5254/1.3601885 ◽

2011 ◽

Vol 84 (4) ◽

pp. 507-519 ◽

Cited By ~ 63

Author(s):

C. G. Robertson ◽

C. J. Lin ◽

R. B. Bogoslovov ◽

M. Rackaitis ◽

P. Sadhukhan ◽

...

Keyword(s):

Glass Transition ◽

Coupling Agent ◽

Volume Fraction ◽

Polymer Chains ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Polymer Filler ◽

Bound Rubber ◽

Filler Network ◽

Styrene Butadiene

Abstract The introduction of silanes to improve processability and properties of silica-reinforced rubber compounds is critical to the successful commercial use of silica as a filler in tires and other applications. The use of silanes to promote polymer–filler interactions is expected to limit the development of a percolated filler network and may also affect the mobility of polymer chains near the particles. Styrene-butadiene rubber (SBR) was reinforced with silica particles at a filler volume fraction of 0.19, and various levels of filler–filler shielding agent (n-octyltriethoxysilane) and polymer–filler coupling agent (3-mercaptopropyltrimethoxysilane) were incorporated. Both types of silane inhibited the filler flocculation process during annealing the uncured rubber materials, thus reducing the magnitude of the Payne effect. In contrast to the significant reinforcement effects noted in the strain-dependent shear modulus, the bulk modulus from hydrostatic compression was largely unaltered by the silanes. Addition of polymer–filler linkages using the coupling agent yielded bound rubber values up to 71%; however, this bound rubber exhibited glass transition behavior which was similar to the bulk SBR response, as determined by calorimetry and viscoelastic testing. Modifying the polymer–filler interface had a strong effect on the nature of the filler network, but it had very little influence on the segmental dynamics of polymer chains proximate to filler particles.

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STUDY ON NANOMORPHOLOGY OF HIGH-STRUCTURE CARBON BLACK AND ITS BOUND RUBBER BY AFM

Surface Review and Letters ◽

10.1142/s0218625x12500035 ◽

2012 ◽

Vol 19 (01) ◽

pp. 1250003

Author(s):

JIAN CHEN ◽

YONGZHONG JIN ◽

JINGYU ZHANG ◽

YAFENG WU ◽

CHUNCAI MENG

Keyword(s):

Carbon Black ◽

Cluster Structure ◽

Chemical Activity ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Atomic Force ◽

Filled Rubber ◽

Bound Rubber ◽

Styrene Butadiene ◽

High Structure

Bound rubber in carbon black (CB) filled rubber (natural rubber (NR) and styrene–butadiene rubber (SBS)) was prepared by the solvent method. The nanomorphology of CB and rubber/CB soluble rubber was observed by atomic force microscope. The results show that high-structure CB DZ13 has a "grape cluster" structure which consists of many original particles with the grain size of about 30–50 nm. Graphitizing process of CB decreases the amount of bound rubber. The NR/DZ13 soluble rubber with island–rim structure has been obtained, where the islands are DZ13 particles and the rims around the islands are occupied by NR film. But when the graphitized DZ13 particles were used as fillers of rubber, we have only observed that some graphitized DZ13 particles were deposited on the surface of the globular-like NR molecular chains, instead of the spreading of NR molecular chains along the surface of DZ13 particles, indicating that graphitized DZ13 has lower chemical activity than ungraphitized DZ13. Especially, we have already observed an interesting unusual bound rubber phenomenon, the blocked "bracelet" structure with the diameter of about 600 nm in which CB particles were blocked in ring-shaped SBS monomer.

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Dynamo-mechanical analysis of rubbers with mineral fillers in comparison with fillers widely used in the tire industry

ВЕСТНИК ПЕРМСКОГО УНИВЕРСИТЕТА ФИЗИКА ◽

10.17072/1994-3598-2021-4-05-13 ◽

2021 ◽

pp. 05-13

Author(s):

Oleg K. Garishin ◽

◽

Anton Y. Beliaev ◽

Keyword(s):

Experimental Testing ◽

Loss Modulus ◽

Mechanical Analysis ◽

Operating Conditions ◽

Styrene Butadiene Rubber ◽

Structural Level ◽

Butadiene Rubber ◽

Tire Industry ◽

Mineral Fillers ◽

Styrene Butadiene

The work is devoted to the study of nanocomposites based on synthetic (styrene-butadiene) rubber with different fillers not previously used. The issue of using composites with alternative fillers is being investigated. The results of experimental testing and analysis of thermo-visco-elastic behav-ior of styrene-butadiene rubbers filled by various mineral particles of micro and nanosize, as well as pyrolysis products of organic food waste, are presented. The filled elastomers discussed in this work are mainly used in the tire industry to improve the performance of tires. All samples were tested on a dynamo-mechanical analyzer (DMA). Temperature and frequency dependences of the dynamic modulus and loss modulus are plotted for each of the composites. The frequency charac-teristics corresponded to the real range of rotation speeds of the car wheel, and the temperature var-ied from –50 to +50ºC. A comparative analysis of the results obtained was carried out. The struc-tural mechanisms of the filler are not investigated. It is assumed that the principles of operation of the investigated fillers at the structural level are similar to those described in many works for clas-sical fillers. Based on the test results a conclusion about the preferable operating conditions for the considered materials was made.

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Understanding Wet Skid Resistance Testing with the British Pendulum Skid Tester: Analysis of Sliding Noise from Various Filled Compounds

Rubber Chemistry and Technology ◽

10.5254/1.3548268 ◽

2010 ◽

Vol 83 (1) ◽

pp. 97-122 ◽

Cited By ~ 1

Author(s):

Xiao-Dong Pan ◽

Paul Zakelj ◽

Cara Adams ◽

Akiko Neil ◽

Greg Chaplin

Keyword(s):

Volume Fraction ◽

Concrete Surface ◽

Resistance Testing ◽

Styrene Butadiene Rubber ◽

Skid Resistance ◽

Butadiene Rubber ◽

Portland Cement Concrete ◽

Frequency Range ◽

Rubber Compounds ◽

Wet Skid Resistance

Abstract The British pendulum skid tester (BPST) has been widely adopted for laboratory characterization of wet skid resistance (WSR) for rubber compounds. However, testing results are not yet well explained with material properties. For filled compounds made of the same styrene-butadiene rubber, on a Portland cement concrete surface wetted with water, WSR for compounds filled with inorganic oxides is higher than WSR for compounds filled with carbon black at the same filler volume fraction. However, such difference in WSR is eliminated under ethanol lubrication. Difference in WSR remains under ethanol lubrication between compounds filled with a reinforcing filler and compounds filled with a nonreinforcing filler. Accepting that dynamic deformation of rubber occurs in the frequency range between 103 and 106 Hz during testing with the BPST, loss tangent for the compounds is measured at various low temperatures but fails to correlate with WSR detected under water lubrication. Modification of bulk viscoelasticity from ethanol absorption should not be neglected for consideration of WSR under ethanol lubrication. During testing with the BPST, sliding noise generated by the assemblage of the spring and lever system in the pendulum with a rubber slider attached is captured under varied lubrication conditions. Both viscoelastic properties of rubber compounds and lubrication condition significantly affect sliding noise. However, no strict correlation between the intensity of sliding noise and WSR is observed. From frequency domain analysis, major components of the sliding noise lie in the frequency range between 500 and 5000 Hz for most compounds. For better understanding on testing with the BPST, modes of material deformation during dynamic sliding on a wet rough surface need to be further scrutinized.

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Visualization of chemical bonding in a silica-filled rubber nanocomposite using STEM-EELS

Scientific Reports ◽

10.1038/s41598-020-78393-0 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Yohei K. Sato ◽

Yasufumi Kuwauchi ◽

Wakana Miyoshi ◽

Hiroshi Jinnai

Keyword(s):

Spatial Distribution ◽

Silica Nanoparticles ◽

Chemical Bonding ◽

Adhesive Layer ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Filled Rubber ◽

Scanning Transmission ◽

Strong Adhesion ◽

Matrix Region

AbstractIn nanocomposites, the adhesion between nanofillers and the polymeric matrix is key to the mechanical properties. The strength and spatial distribution of the adhesive layer around the nanofillers are important, particularly the presence of chemical bonding between the nanofillers and matrix. In this work, we studied a styrene-butadiene rubber composite filled with silica nanoparticles to visualize the spatial distribution of the adhesive layer. A silane coupling agent (SCA) was added to the nanocomposite for strong adhesion. The reaction involving the SCA on the silica surface was investigated by scanning transmission electron microscopy combined with electron energy-loss spectroscopy. Si-L2,3 spectra of the silica-filled rubber nanocomposite without the SCA were the same around the nanofillers, whereas in the nanocomposite containing the SCA the spectra were position-dependent. The spectra were fitted with the intensity profiles of the Si-L2,3 spectra of silica and SCA by multiple linear least-squares fitting. The fitting coefficients of silica and SCA were used to map the spatial distribution of the chemical bonding between silica and rubber chains. Chemical bonding was observed around the silica nanoparticles but not in the SBR matrix region, providing direct evidence of the reinforcing mechanism in the silica-filled rubber nanocomposite.

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