New Ideas on the Molecular Colloidal Structure of Filled Rubber Compounds

Abstract There has been a great deal of research on the effects of ground rubber (GR) on the cure characteristics of GR-filled rubber compounds. It has been known that the cure systems of the rubber matrix and GR also had an effect on the cure characteristics and physical properties of GR-filled compounds. In this study, the variation of the crosslink density and crosslink types of recured vulcanizates and fresh vulcanizates, with respect to the cure systems, were investigated by using a three-layered model. In addition, the adhesion forces between recured vulcanizates and fresh vulcanizates were measured, and the fracture surfaces were examined. Depending on the cure systems, the changes in the crosslink density and crosslink types of recured and fresh vulcanizates varied significantly and the failure modes of adhesion specimens were also different.

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Flocculation in Silica Reinforced Rubber Compounds

Rubber Chemistry and Technology ◽

10.5254/1.3548262 ◽

2009 ◽

Vol 82 (5) ◽

pp. 524-540 ◽

Cited By ~ 52

Author(s):

S. Mihara ◽

R. N. Datta ◽

J. W. M. Noordermeer

Keyword(s):

Activation Energy ◽

Coupling Agent ◽

Physical Phenomenon ◽

Interfacial Interaction ◽

Shielding Effect ◽

Interaction Layer ◽

Filled Rubber ◽

Rubber Compounds ◽

Bound Rubber ◽

Flocculation Rate

Abstract Flocculation plays an important role in reinforcement of silica filled rubber compounds, even if coupling agents are applied. It is well known that silica tends to flocculate during the early stages of vulcanization, when no dense rubber network has been formed yet. In the present study, flocculation was monitored by following the change in storage modulus at low strain, the so-called Payne effect, using a RPA2000 dynamic mechanical tester. The kinetic parameters: the rate constant and the activation energy of the silica flocculation were calculated according to the well-known Arrhenius equation. On basis of the value of the activation energy obtained for flocculation, it can be concluded that the silica flocculation is a purely physical phenomenon. Bound rubber measurements were also done in order to estimate the interfacial interaction layer between silica and polymer resulting from the coupling agent. The silica flocculation rate decreases with increasing interfacial interaction layer on the silica surface. This indicates that the decrease of the flocculation rate is due to the shielding effect of the coupling agent. It is argued that the attractive flux from forces related to polarity differences between the silica and the rubber is the determining factor for silica flocculation.

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Online Method for Characterization of the Homogeneity of Rubber Compounds Filled with Non-Conductive Carbon Black

Rubber Chemistry and Technology ◽

10.5254/1.3547955 ◽

2006 ◽

Vol 79 (4) ◽

pp. 610-620 ◽

Cited By ~ 4

Author(s):

H. H. Le ◽

M. Tiwari ◽

S. Ilisch ◽

H-J. Radusch

Keyword(s):

Carbon Black ◽

Electrical Conductance ◽

Rubber Compound ◽

Mixture Ratio ◽

Dispersion Process ◽

Filled Rubber ◽

Rubber Compounds ◽

Conductance Method ◽

Internal Mixer

Abstract In the present work, the effect of carbon black (CB) type on the electrical conductance of CB filled rubber compounds measured online in the internal mixer and the corresponding CB dispersion were investigated. The CB dispersion is strongly affected by the specific surface area and structure of CB which can be directly monitored by use of the online electrical conductance method. The effect of CB mixture ratio of a high conductive CB and a non-conductive one on the online electrical conductance was investigated for CB filled rubber compounds. By addition of a small amount of a high-conductive CB type into a non-conductive CB filled rubber compound, a characteristic online conductance - time characteristic is observed that is a result of the formation of a joint network of the two CB types. It could be shown, that such a characteristic is suitable to monitor the dispersion process of the non-conductive CB in the rubber compound.

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Superharmonic Resonance in Carbon-Black-Filled Rubber by High-Frequency DMA

Polymers ◽

10.3390/polym11101653 ◽

2019 ◽

Vol 11 (10) ◽

pp. 1653

Author(s):

Imran Hussain Syed ◽

Jorge Lacayo-Pineda

Keyword(s):

Carbon Black ◽

High Frequency ◽

Model Compound ◽

Resonance Phenomenon ◽

Superharmonic Resonance ◽

Filled Rubber ◽

Rubber Compounds ◽

Resonance Response ◽

Filler Network ◽

Main Influence

A systematic study of several SBR compounds filled with carbon black of various grades were analysed with the high-frequency Dynamic Mechanical Analyzer (HF DMA) in order to quantify the degree of nonlinearity induced by fillers in rubber compounds. These filler grades indirectly reflect different degrees of microdispersion, which seems to be the main influence on the superharmonic resonance phenomenon observed in HF DMA. This statement arises from the comparison of the microdispersion observed in TEM images. In the second part of the paper, a model compound filled with carbon black is enhanced with a standard reinforcing resin, which leads to a more compact filler network. This induces a higher superharmonic resonance response as well as a higher transmissibility behaviour.

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Test Methods for Hyperelastic Characterization of Rubber4

Tire Science and Technology ◽

10.2346/1.3138763 ◽

2009 ◽

Vol 37 (3) ◽

pp. 165-186 ◽

Cited By ~ 3

Author(s):

R. Kupchella ◽

J. Kidney ◽

W. Hutchison

Keyword(s):

Three Dimensional ◽

Test Methods ◽

Biaxial Stress ◽

Image Correlation ◽

Optical Methods ◽

Filled Rubber ◽

Rubber Compounds ◽

Stress States ◽

Property Changes

Abstract Optical methods using digital image correlation (DIC) are utilized in developing rubber constitutive tests. Two and three dimensional DIC systems are employed to measure strains on rubber specimens subjected to uniaxial, planar, and biaxial stress states. A special membrane inflation test was developed and is described for providing the biaxial constitutive data. Deformation-induced material property changes for the three modes of testing are quantified using a concept based on energy dissipation. The constitutive test strain ranges for each of the three modes are separately selected to equalize the material states. The methodology is applied to filled rubber compounds in order to characterize them in terms of hyperelastic behavior. Evaluation and comparison of several common hyperelastic models are given, and application to finite element modeling of a structural rubber specimen is described.

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