Natural rubber

About: Natural rubber is a research topic. Over the lifetime, 111249 publications have been published within this topic receiving 763842 citations. The topic is also known as: India rubber & caoutchouc.

The physics of rubber elasticity

Abstract: 1. General Physical Properties of Rubber 2. Internal Energy and Entropy Changes on Deformation 3. The Elasticity of Long-Chain Molecules 4. The Elasticity of a Molecular Network 5Ex5 Experimental Examination of the Statistical Theory 6. Non-Gaussian Chain Statistics and Network Theory 7. Swelling Phenomena 8. Cross-linking and Modulus 9. Photoelastic Properties of Rubbers 10. The General Strain: Phenomenological Theory 11. Alternative Forms of Strain-Energy Function 12. Large-Deformation Theory: Shear and Torsion 13. Thermodynamic Analysis of Gaussian Network

A three-dimensional constitutive model for the large stretch behavior of rubber elastic materials

Abstract: Aconstitutive model is proposed for the deformation of rubber materials which is shown to represent successfully the response of these materials in uniaxial extension, biaxial extension, uniaxial compression, plane strain compression and pure shear. The developed constitutive relation is based on an eight chain representation of the underlying macromolecular network structure of the rubber and the non-Gaussian behavior of the individual chains in the proposed network. The eight chain model accurately captures the cooperative nature of network deformation while requiring only two material parameters, an initial modulus and a limiting chain extensibility. Since these two parameters are mechanistically linked to the physics of molecular chain orientation involved in the deformation of rubber, the proposed model represents a simple and accurate constitutive model of rubber deformation. The chain extension in this network model reduces to a function of the root-mean-square of the principal applied stretches as a result of effectively sampling eight orientations of principal stretch space. The results of the proposed eight chain model as well as those of several prominent models are compared with experimental data of Treloar (1944, Trans. Faraday Soc. 40, 59) illustrating the superiority, simplicity and predictive ability of the proposed model. Additionally, a new set of experiments which captures the state of deformation dependence of rubber is described and conducted on three rubber materials. The eight chain model is found to model and predict accurately the behavior of the three tested materials further confirming its superiority and effectiveness over earlier models.

A New Constitutive Relation for Rubber

Abstract: A simple, two-constant, constitutive relation, applicable over the entire range of strains, is proposed for rubber networks. Behavior in simple extension is derived as an example.

Theory of rubber friction and contact mechanics

Abstract: When rubber slides on a hard, rough substrate, the surface asperities of the substrate exert oscillating forces on the rubber surface leading to energy “dissipation” via the internal friction of the rubber. I present a discussion of how the resulting friction force depends on the nature of the substrate surface roughness and on the sliding velocity. I consider in detail the case when the substrate surface has a self affine fractal structure. I also present a theory for the area of real contact, both for stationary and sliding bodies, with elastic or elastoplastic properties. The theoretical results are in good agreement with experimental observation.