Development of Polymer Science

Most early thermoplastics, e.g., PVC or PS, were obtained in the free radical polymerization, initiated either by heat or by sunlight. The first systematic studies of the free radical chemistry commenced 80 years later (Ostromislensky 1911, 1915, 1916). Fikentscher empirically determined which one of the 30-or-so monomers liked or disliked to copolymerize with each other. The advantage of latex blending was also established. The theory of the free radical copolymerization was only developed in the 1940s (Alfrey et al. 1952). 

The alkyl-lithium-initiated, living anionic polymerization of elastomers was described in 1928 by Ziegler. To polymerize styrene-isoprene block copolymers, Szwarc et al. (1956) used sodium naphthalene as an anirm-radical di-initiator, while Shell used an organolithium initiator. The polymerization mechanism was described by Bywater (1965). 

MgCl2-supported catalysts that have a 100-fold more active sites per mole of Ti and about ten times higher propagation rate (Rieger et al. 1990). 

The metallocene catalysts are also used to produce high melting point polymers out of commodity monomers, e.g., sPS, with Tg = 100 °C, and T , = 266 °C, or syndiotactic poly(p-phenyl styrene), (sPhPS), with Tg = 196 °C, = 352 °C, and 

Osmotic pressure measurements for the determination of MW were used in 1900 to characterize starch. Twenty years later, the solution viscosity measurements were introduced by Staudinger for this purpose. However, it was Mark and his collaborators who developed the concept of the intrinsic viscosity ([rj]) and demonstrated that it provides information on the volume of individual colloidal particles, thus on MW. 

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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... 

It is most fortunate for the development of polymer science that these imagined complications have turned out to be almost wholly illusory. As will be brought out in the course of this chapter, the influence of molecular size and complexity on chemical reactivity may be disregarded in very nearly all polymer reactions. If this were not the case, application of the principles of reaction kinetics to polymerization and polymer degradation reactions would be difficult, and might be so complicated as to be fruitless. Not only would polymer reaction kinetics... 

Elucidation of the nature of the end groups was important in the development of polymer science, but a more complex step was expression of the magnitude of molecular size. 

I shall confine my remarks to the development of polymer science in America. There was considerable work before that in Europe, but that was before chemistry of polymers became sophisticated and real progress was made in the field. In about 1910 industrial work on polymers began to be carried out, although the understanding of polymers was very meager. The industrial work was done mainly on natural products such as horn and hoof and they were converted into useable materials by various means without much understanding of the real chemistry involved. 

The development of polymer science with the study of new polymerization processes and polymers showed that the original classification by Carothers was not entirely adequate and left much to be desired. Thus, for example, consider the polyurethanes, which are formed by the reaction of diols with diisocyanates without the elimination of any small molecule ... 

Unfortunately, the naming of polymers has not proceeded in a systematic manner until relatively late in the development of polymer science. It is not at all unusual of a polymer to have several names because of the use of different nomenclature systems. The nomenclature systems that have been used are based on either the structure of the polymer or the source of the polymer [i.e., the monomer(s) used in its synthesis] or trade names. Not only have there been several different nomenclature systems, but their application has not always been rigorous. An important step toward standardization was initiated in the 1970s by the International Union of Pure and Applied Chemistry. 

In her chapter, Bernadette Bensaude-Vincent traces the evolution of materials science in three different ways. In her opening section, Bensaude-Vincent shows how the traditional discipline of metallurgy was changed by its contacts with the emerging science of solid-state physics and also X-ray crystallography. One can see parallels with the development of polymer science outlined in Furukawa s chapter. 

Scientific and technological progress, like other areas of human endeavor advances by a cyclical process of gradual evolution interspersed -with occasions of scientific revolution (Mark 1987). For example, let s consider Figure 10-1, which illustrates the development of polymer science through the commercialization of one family of polymers, polyolefins (Sinclair 2001). One could construct a similar plot for other families of polymers. Revolutionary episodes... 

The search for quantitative structure-property relationships for the control and prediction of the mechanical behaviour of polymers has occupied a central role in the development of polymer science and engineering. Mechanical performance factors such as creep resistance, fatigue life, toughness and the stability of properties with time, stress and temperature have become subjects of major activity. Within this context microhardness emerges as a property which is sensitive to structural changes. 

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

It has been demonstrated that solid state NMR spectroscopy provides useful information about the structure and dynamics of polymers in the bulk. At present, in polymer science, solid state NMR is recognized as one of the most powerful means for elucidating the structure and the dynamics of solid polymers in addition to X-ray diffraction. The history of solid state NMR, which has been used in polymer science, is very old. The appearance of new techniques in solid state NMR has certainly contributed to the development of polymer science and technology. 

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... 

The contributions by Ziegler and Natta caused great industrial impact and large advances in research and development of polymer science and engineering, as new kinds of... 

Up till now, when a new development was required from polymer science, it has been possible to design and obtain a new polymer fitting that particular requirement. The most challenging tasks for polymer science were rather of a more logistical nature than scientific. For example, a reduction in the number of different polymers used in practice to cover the whole range of consumer demands (in order to simpHfy and make more profitable their manufacture) has been and still is the cause of important research efforts. Additionally, environmental and other related matters, such as sustainabiUty, have also been addressed, but they have always remained in the background and have not significantly limited the development of polymer science. 

The general reference to the book by Flory contains a brief, expert summary of the history of knowledge about polymers and is a treatise on polymer physical chemistry. (See also the list of general references for this section). The delay in development of polymer science due to the misunderstanding of colloid science (microphases) is discussed next. 

Vorlander assigned increasing ring sizes to the polymers, thus postponing the development of polymer science... 

Competition led to the rapid development of polymer science and technology. Competition also reinforced the search for product differentiation as a way of relaxing price competition, encouraging additional investments in research and development to develop new products or variants of existing ones. 

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