Polymer science, definition

The polymer-solvent interaction parameter, which is a key constant defining the physical chemistry of every polymer in a solvent, can be obtained from electrochemical experiments. Definition and inclusion of this interaction was a milestone in the development of polymer science at the beginning of the 1950s. We hope that Eq. 47 will have similar influence in the development of all the cross-interactions of electrochemistry and polymer science by the use of the ESCR model. A second point is that Eq. 47 provides us with an efficient tool to obtain this constant in electroactive... 

Dr. Mark is acknowledged throughout the scientific community as the father of polymer science. He received the National Medal of Science in 1980, the 1978 Senior U.S. Scientist Award, 29 other medals and awards from various international organizations, and 17 honorary degrees. In 1977, he was appointed as an Honorable Member of the Japan Chemical Society. He has published over 500 original and review articles and some 20 books on topics related to polymer chemistry. Dr. Mark is founder and first editor of the Journal of Polymer Science, the definitive publication in its field, and is currently editor of the Journal of Applied Science and associate editor of the Textile Research Journal. In addition to these duties he serves as Chairman of the Editorial Board of the Encyclopedia of Polymer Science and Technology. 

Written by foremost experts in the field from industry and academia, these books place particular emphasis on structure-property relationships of polymers and manufacturing technologies as well as their practical and novel applications. The aim of each book in the series is to provide readers with an in-depth treatment of the state-of-the-art in that field of polymer technology. Collectively, the series will provide a definitive library of the latest advances in the major polymer families as well as significant new fields of development in polymer science. 

In order to present clear concepts it is necessary that idealized definitions be adopted but it is reeognized that the realities of polymer science must be faced. Deviations from ideality arise with polymers at both molecular and bulk levels in ways that have no parallel with the ordinary small molecules of organic or inorganic chemistry. Although such deviations are not explicitly taken into account in the definitions below, the terms recommended can usefully be applied to the predominant structural features of real polymer molecules, if necessary with self-explanatory, if imprecise, qualifications such as essentially. , almost completely. , or highly. . Although such expressions lack the rigour beloved by the purist, every experienced polymer scientist knows that communication in this discipline is impossible without them. 

This document relies on the basic definitions of terms in polymer science [1]. It was the second in a series published by the Commission on Macromolecular Nomenclature dealing with definitions of physical and physicochemical terms in the polymer field (for the first in the series, see Reference [2]). 

This document provides definitions of the basic terms that are widely used in the field of liquid crystals and in polymer science (See references 1-39). It is the first publication of the Commission on Macromolecular Nomenclature dealing specifically with liquid crystals. 

Note 1 The term as defined here is specific to polymer science. An alternative definition of impregnation applies in some other fields of chemistry [3]. 

The first publication of the lUPAC in the area of macromolecular nomenclature was in 1952 by the Sub-commission on Nomenclature of the then lUPAC Commission on Macromolecules, which drew on the talents of such remarkable individuals as J. J. Hermans, M. L. Huggins, O. Kratky, and H. F. Mark. That report [1] was a landmark in that, for the first time, it systematized the naming of macromolecules and certain symbols and terms commonly used in polymer science. It introduced the use of parentheses in source-based polymer names when the monomer from which the polymer is derived consists of more than one word, a practice that is now widely followed, and it recommended an entirely new way of naming polymers based on their structure that included the suffix amer , a recommendation that has been almost totally ignored. After ten years, the Sub-commission issued its second report [2], which dealt with the then-burgeoning field of stereoregular polymers. A revision [3] of definitions in the original report appeared four years later. In 1968, a summary report [4] of the activities of the Subcommission was published. 

With all of the advances in polymer science and conjugation technology, many methods have been developed to increase the feasibility of oral peptide and protein delivery. There is still no single mechanism that can be used to protect a protein or peptide from degradation and increasing oral availability, but with the multitude of new methods for allowing a protein to negotiate natural barriers, oral delivery of any systemically active protein is a definite possibility at some point in the future. 

Definitions we use. Extended chain is also defined as fully extended. But also see Ref. [7], which suggests these terms have been used in various contexts in polymer science, resulting in a certain amount of confusion... 

The current status of polymer science, and other materials-related research, within chemical engineering demands a wider definition of what is fruitful activity within the profession than that of 20 years ago. Polymer sci-... 

Some of the definitions in this glossary have been adapted from Billmeyer, F. W Textbook of Polymer Science, 3rd ed., Wiley Sons, New York, NY (1984) and Lapedes, D. N., ed., McGraw-Hill Dictionary of Scientific and Technical Terms, 2nd ed., McGraw-Hill, New York, NY (1978). 

Some basic concepts and definitions of terms used in the polymer literature are reviewed in this chapter. Much of the terminology in current use in polymer science has technological origins, and some meanings may therefore be understood by convention as well as by definition. Some of these terms are included in this chapter since a full appreciation of the behavior and potential of polymeric materials requires acquaintance with technical developments as well as with the more academic fundamentals of the field. An aim of this book is to provide the reader with the basic understanding and vocabulary for further independent study in both areas. 

Functionality is a very useful concept in polymer science, and we use it later in this book. There arc, however, other definitions than the one given here. All arc valuable in their proper contexts. 

There are as yet no standards defining the properties of such samples these will clearly need to emerge as these materials become more generally utilised. Such standards will owe more to the definitions of materials and/or polymer science than to the world of the molecule and will include definitions probably statically derived from ... 

Fig. 3. Arrhenius plot of the viscosity of several supercooled liquids. The horizontal dotted line, where the viscosity reaches 10 P, is commonly used as a definition of the glass transition. (Reprinted with permission from C. A. Angell. Formation of glasses from liquids and polymers. Science (1995) 267 1924. Copyright (1995), American Association for the advancement of Science.)...

With the development of polymer science and the synthesis of new polymers, the previous definition of condensation polymer is inadequate. For... 

Molecular conformation is an important subject of concern in liquid crystalline polymers. It is also the basic subject of polymer science. The mean square end-to-end distance or the radius of gyration is often used to characterize the size of a polymer molecule. According to the definition, the end-to-end distance is the sum of each rod s vectors in sequence... 

This definition of integral distribution function is common in colloid science, while in polymer science the molecular weight distributions are typically evaluated by the summation of molecular weight smaller than the current value... 

Many of the terms, definitions, and concepts used in polymer science are not encountered in other branches of science and must be understood in order to fully discuss the synthesis, characterization, structure, and properties of polymers. While most of these will be discussed in detail in subsequent chapters, some are of such fundamental importance that they must be introduced at the beginning. 

With the development of polymer science and the synthesis of new polymers, the previous definition of condensation polymer is inadequate. For example, in polyurethanes (Table 1.2), which are classified as condensation polymers, the repeating unit has the same net composition as the two monomers (i.e., a diol and a diisocyanate), which react without eliminating any small molecule. To overcome such problems, chemists have introduced a definition which describes condensation polymers as consisting of structural units joined by internal functional groups... 

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