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Polymers historical development

Yang L, Tan X, Wang Z, Zhang X. Supramolecular polymers historical development, preparation, characterization, and functions. Chem Rev. 2015 115 7196-7239. [Pg.70]

There are two problems in the manufacture of PS removal of the heat of polymeriza tion (ca 700 kj /kg (300 Btu/lb)) of styrene polymerized and the simultaneous handling of a partially converted polymer symp with a viscosity of ca 10 mPa(=cP). The latter problem strongly aggravates the former. A wide variety of solutions to these problems have been reported for the four mechanisms described earlier, ie, free radical, anionic, cationic, and Ziegler, several processes can be used. Table 6 summarizes the processes which have been used to implement each mechanism for Hquid-phase systems. Free-radical polymerization of styrenic systems, primarily in solution, is of principal commercial interest. Details of suspension processes, which are declining in importance, are available (208,209), as are descriptions of emulsion processes (210) and summaries of the historical development of styrene polymerization processes (208,211,212). [Pg.521]

Polymers are not only an important topic of chemistiy because of their matty applications in everybody s daily-life, they are also interesting because of the theories that can be applied to explain and to design polymers and their properties. However, the teaching experiments and interviews gave hints that the historical development of theories to explain polymers and the students explanations are not as coherent as for... [Pg.241]

Generally, the values of the scaling exponent are smaller for polymers than for molecular liquids, for which 3.2 < y < 8.5. A larger y, or steeper repulsive potential, implies greater influence of jamming on the dynamics. The smaller exponent found for polymers in comparison with small-molecule liquids means that volume effects are weaker for polymers, which is ironic given their central role in the historical development of free-volume models. The reason why y is smaller... [Pg.661]

The historical development of polyphosphazene chemistry is compared in Figure 2 with those of other inorganic polymer systems. Its origins can be traced to the late 1800 s, ( 1) although the first... [Pg.252]

The historical development of alkyllithium-initiated polymerization of olefins and diolefins for the synthesis of elastomeric materials is of interest not only because of its scientific and technological significance but also because of the insight it provides into the thinking and methodology of polymer (elastomer) researchers. [Pg.55]

X. Li and M. Huang, Historical development in liquid crystalline polymers , Gaofenzi Cailiao Kexue Yu Gongcheng, 1993, 9 (4), 1-8 [in Chinese],... [Pg.88]

Time has come to give careful consideration to the historical development of both terms polymer" and macromolecule . The decision should definitely be in favor of the well defined term macromolecule. This term should be applied to the titles of publications, including journals and books, and particularly to the names of institutions of scientific research. They should be named for macromolecular science and no longer include the term polymer. [46]... [Pg.240]

XPS and other surface analysis techniques to the study of electroactive polymers and their molecular modifications are pointed out We assume that the readers are familiar with the historical development of electroactive polymers since the pioneering work on (CH)X [4, 5],... [Pg.139]

Historically, pricing had been the biggest barrier to biodegradable polymer market development. However, growing volumes of production and the development of new technology should further allow bio-based resin makers to reduce costs. Using materials such as corn stover, wheat straw and rice straw, which remain in fields after crops are harvested, as resin feedstock, could also increase productivity and economic performance. [Pg.38]

This historical development of the radiation technology of polymers is reviewed in this outline. The important applications of this technology are divided into two classes - large scale processes such as cross-linking of rubbers and plastics and specialized sophisticated processes such as microlithography. The initial fundamental studies that led to these applications are outlined and the slow process of commercialization is emphasized in this review. [Pg.31]

Polymer technology is quite old compared to polymer science. For example, natural rubber was first masticated to render it suitable for dissolution or spreading on cloth in 1820. and the first patents on vulcanization appeared some twenty years later. About another one hundred years were to elapse, however, before it was generally accepted that natural rubber and other polymers are composed of giant covalently bonded molecules that differ from ordinary molecules primarily only in size. (The historical development of modern ideas of polymer constitution is traced by Flory in his classical book on polymer chemistry [ I ], while Brydson [2] reviews the history of polymer technology.) Since some of the terms we are going to review derive from technology, they are less precisely defined than those the... [Pg.1]

Polymer nanoparticles including nanospheres and nanocapsules (Fig. 1) can be prepared according to numerous methods that have been developed over the last 30 years. The development of these methods occurred in several steps. Historically, the first nanoparticles proposed as carriers for therapeutic applications were made of gelatin and cross-linked albumin. Then, to avoid the use of proteins that may stimulate the immune system and to limit the toxicity of the cross-linking agents, nanoparticles made from synthetic polymers were developed. At first, the nanoparticles were made by emulsion polymerization of acrylamide and by dispersion polymerization of methylmethacry-late.f These nanoparticles were proposed as adjuvants for vaccines. However, since they were made of non-biodegradable polymers, these nanoparticles were rapidly substituted by particles made of biodegradable... [Pg.1183]

TABLE 3. Historical development of the advances of ultrafiltration in conjunction with soluble polymer reagents. [Pg.145]

Although we did not publish our domain theory in 1965, it was fairly evident to those acquainted with the historical developments in Table II that the new products were three-block polymers. Researchers in the field very rapidly commenced to use these polymers as models for comparison and as subject for physicochemical studies. Evidence for this may be seen in the work reported by Cooper and Tobolsky (42) in 1966, in which they correlated the behavior of polyester-polyurethane thermoplastic rubbers (Estane products) (37) with those of a Shell S-B-S polymer. They concluded that the presence of segregated hard and soft phases in the Estane... [Pg.183]

Historical Development of Organometallic Polymers 12.06.2 Side-Chain Organometallic Polymers... [Pg.295]

Historical Development of Hydrophobe-Modified Water-Soluble Polymers... [Pg.151]

The historical development of associative thickeners has followed the usual phases of polymer development. The products available in the early 1960s were probably prepared with little thought of the concepts presented in the related chapters of this text. Somewhere, these products sparked the concept of induced micelle participation of polymeric hydrophobes and of a synergistic influence on viscosity. The somewhere was probably two places. Midland, MI, and Rutgers, NJ. These contributions were taken with others from continental Europe and focused on the coatings industry and, with time, on other industries. [Pg.162]


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See also in sourсe #XX -- [ Pg.1035 , Pg.1037 ]




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