Polymer science rubber elasticity

In the presence of excluded volume (net repulsion, i.e. x < /a) a polymer coil will favor those configurations that are more diffuse (expanded, swollen). From the point of view of eq. 1.3, the effective energy will be lower if the concentration is lower. However, what is usually described in polymer science as elastic forces oppose the swelling, limiting it. The number of configurational states available to a swollen polymer is lower than in an unswollen state, giving rise to the entropic force responsible for rubber elasticity, and to resistance to swelling. 

Eleinrich, G., Straube, E., and Helmis, G. Rubber elasticity of polymer networks theories. Advances in Polymer Science 85, 33 (1988). 

The Science of Polymer Molecules, by R. H. Boyd and P. J. Phillips, CUP, 1993. This book focuses on the synthesis, structure and properties of polymer molecules, covering such topics as molar masses, chain statistics, rubber elasticity and polymer solutions. The level is generally more advanced than that of the present book, but some sections are relatively straightforward. 

Thermodynamics, both classical [Appendix 3.A] and statistical [Appendix 2A], have been applied to many topics in polymer science. The results have provided insights into the origin of rubber elasticity, the nature of polymer crystalline, polymeric heat capacities and the miscibility of polyblends. 

Lai J, Mark JE (eds) (1986) Advances in elastomers and rubber elasticity. Plenum, New York Legge NR, Holden G, Schroeder HE (eds) (1987) Thermoplastic elastomers. Hanser, Munich Lewis RJ (1999) Sax s dangerous properties of industrial materials, 10th edn. Wiley, New York Mark JE, Bikales NM, Overberger CG, Menges G (eds) (2004) Encyclopedia of polymer science and engineering, vol 1-12. Wiley, New York... 

Allen G, Bevington J (eds) (1989) Comprehensive polymer science, vol 6. Pergamon, Oxford Eisenbach CD, Baumgartner M, Guenter C (1986) In Lai J, Mark JE (eds) Advances in elastomers and rubber elasticity (Polyurethanes). Plenum, New Yrak Gachter R, Muller H (eds) (1993) Plastics additives handbook, 4th edn. Hanser, Munich Houben-Weyl (1987) Methoden der organischen Chemie, vol E20, Makromolekulare Stoffe, Thieme, Stuttgart... 

The theory of rubber elasticity is largely based on thermodynamic considerations. It will be briefly discussed as an example of how thermodynamics can be applied in polymer science. Eor more detailed information the reader is referred to the various textbooks [10-13]. It is assumed that there is a three-dimensional network of chains, that the chain units are flexible and that individual chain segments rotate freely, that no volume change occurs upon deformation, and that the process is reversible (i.e., true elastic behavior). Another usual assumption is that the internal energy U of the system does not change with deformation. Eor this system the first law of thermodynamics can be written as ... 

The above features of rubbery materials have long been known. The quantitative measurements of mechanical and thermodynamic properties of natural and other elastomers go back to 1805 and some of the studies were conducted by luminaries like Joule and Maxwell. The first molecular theory in polymer science dealt with the rubber elasticity (9-12). 

The introduction of thermoplastic elastomers (TPEs) during the late 1950s is one of the most important developments in the field of polymer science and technology. TPEs are a relatively new class of material, a blend of rubber and thermoplastic that combine a wide range of the physical properties of elastomers, such as elasticity, at room and service temperatures, and the excellent... 

The theory of rubber elasticity is one of the oldest theories in polymer science and has played a central role in its development. Now one of the key... 

The present book is a sequel to "Elastomers and Rubber Elasticity," edited by J.E. Mark and J, Lai and published by the American Chemical Society in 1982. It is also based on papers presented at an ACS Symposium, sponsored by the Division of Polymer Chemistry, Inc., in this case one held in Chicago in September of 1985. The keynote speaker was to have been Professor Paul J. Flory, and his untimely death just prior to the symposium was a tremendous loss to all of pol3nner science, in particular to those interested in elastomeric materials. It is to his memory that this book is dedicated. 

Liquid crystal elastomers combine the unique properties of rubber elasticity with the anisotropy of the liquid crystalline state. Although intensive research has been performed during the past few years, and the first liquid crystal elastomers had only been synthesized in 1981, knowledge about these materials is still in its infancy. This is due to the complex interplay between the polymer network and the anisotropic order of the liquid crystalline state. On the other hand, liquid crystal elastomers offer new aspects for chemistry, physics, and material science [1], [2], [3], [4]. 

The theory of rubber elasticity Is central to polymer science. This property of recoverable, high extensibility Is manifested under suitable conditions by virtually all macromolecular substances consisting predominantly of long chains. Moreover, It Is ejdilblted exclusively by materials so constituted. Rubber elasticity Is essential to the functioning of elastic proteins and of muscle. It Is operative also In the deformation of seml-crystalllne polymers, generally not Included In the category of rubbers. 

But for the hard science of rubber elasticity, see P. J. Flory, Principles of Polymer Chemistry CovndlUmvetsity Press, 1953). 

One of the most characteristic properties of gel is the rubber elasticity. Rubber elasticity has attracted attention since fire early era of polymer science research and has been developed through statistical mechanics [35, 36]. The basis of rubber elasticity is the micro-Brownian motion of the polymer chains [37]. Specifically, the rubber elasticity originates fixrm entropy and is mechanistically different from the energetic elasticity of fire crystalline solid. The ideal relationship between stress and strain is given by... 

Another organizing principle for the story is the key books that documented the establishment of paradigms in polymer science. Interscience published a series of books called High Polymers . It was edited by Herman Mark and a constantly changing cast of other leaders in polymer science. Many of these volumes are reviewed in detail in this story. There is also an eclectic group of monographs that are still considered classics, such as L.R.G. Treloar s The Physics of Rubber Elasticity [5]. Any scientific community is partially defined by its favorite books, and the author of the present volume is the Chief Bibliophile of the Bolton Society of the Chemical Heritage Foundation. 

The above-mentioned general features of elastomeric materials have long been known and, in fact, the area of rubber-like elasticity has had one of the longest and most distinguished histories in all of polymer science (1,2,16). Forex-ample, quantitative measurements of the mechanical and thermodynamic properties of natural rubber and other elastomers go back to 1805, and some of the earliest studies have been carried out by such luminaries as Joule and Maxwell. Also, the earliest molecular theories for polymer properties of any kind were, in fact, addressed to the phenomenon of rubber-like elasticity. 

Schultz, J.M. (1974), Polymer Materials Science, Prentice-Hall Inc., New Jersey. Treloar, L.R.G. (1958), The Physics of Rubber Elasticity, Clarendon Press, Oxford. 

The physics of rubber elasticity is one of the oldest subjects in polymer science. Outstanding mechanical properties, regardless of the chemical structure, have been the reason for an immense amount of research in many areas of polymer science. Chemists have been able to improve the chemistry of materials in order to find special macroscopic properties. In other chapters of this work we can see how difficulties in the chemistry of crosslinking can be solved. Material scientists are interested in macroscopic properties and macroscopic applications of materials. In our world a life without rubbers and crosslinked polymers would be unimaginable. Packings, gaskets, car tyres are all applications in daily life which need specially designed properties. 

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