Polymer concept

The rapid acceptance of the association theory was accompanied by an equally rapid dropping of the high molecular weight or polymer concept. Olby (31) has stated that three developments made the theory attractive as an explaination for the behavior of polymers. First, he sates, was Alfred Werner s introduction of the concept of two kinds of combining forces—Hauptvalenzen or primary valence forces, and Nebenvalenzen or secondary forces (32). When applied to cellulose, proteins, or rubber, the mole-... 

Several key events also contributed to this transformation. This included an invitation by D. Seebach and H. Ringsdorf to present the dendritic polymer concepts at the prestigious Burgenstock Conference in Switzerland (May, 1987). 

Subsequent epidemiological studies have supported the association between better health and long-term consumption of diets rich in foods of plant origin. " However, whether this is because such diets minimize exposure to deleterious substances (e.g., oxidized cholesterol, pyrolysis mutagens, salt, saturated fat, etc.), or maximize intake of certain beneficial nutrients (e.g., isothiocyanates and other sulfur-containing plant constituents, mono-unsaturated fatty acids, and poly-unsaturated fatty acids, PPT, poly acetylenes, selenium, terpenes, etc.) or some combination as advocated in the Polymeal concept, remains unknown. " An in vitro study indicates that there may be mechanistic basis for true synergy between PPT and isothiocyanates. ... 

M. Szycher and W. J. Robinson, eds., Synthetic Biomedical Polymers Concepts and Applications, Technomic, Westport, Conn. (1980). 

The Dye-in-Polymer concept was first proposed and reduced to practice in our laboratory (12). It involves the ablative marking with an appropriate laser, of a polymer film containing a dissolved dye. The dye-in-polymer film can be easily prepared by spin-coating a dye/polymer solution onto a reflective substrate. The structure of the DIP recording medium is shown in Figure 8. 

G.R. Strobl, The Physics of Polymers, Concepts for Understanding their Structures and Behaviour, Springer Verlag, Berlin, 1996. 

Strobl GR (1996) The physics of polymers concepts for understanding their structures and behavior. Springer, Berlin Heidelberg New York... 

One common possibility for the preparation of low molecular hemiporphyrazines is starting from o-dicyano compounds sudi as 1,2-dicyanbenzene and diamines sudi as 1,4-diaminobenzene or 2,6-diaminopyridine to obtain the ligand followed by introduction of metal ions (in the case using diaminopyridine) In order to get polymers, concepts of bifunctionality with various tetracyano compounds 103) and diamines 104) were used to prepare the polymer ligand 105)-, this is in some cases able to form polychelates 106) (Eq. 57, Table 17). 

Figure 12. Light-induced depolymerization of UPy-based supramolecular polymers. Concept (a) and compounds used (b).

The SA sensory polymer concept was first demonstrated in an analyte-induced quenching assay (Figure la) where the ligand to the receptor site was a quencher [4]. A key feature of the polymeric system was that the exciton migration caused greatly enhanced quenching relative to a chromophore bearing only one of the receptors. This is established by... 

Morawetz, Difficulties in the emergence of the polymer concept an essay, Angew. Chem. Int. Ed. Engl. 26, 93 (1987). 

Szycher, M. Robinson, W.J., Eds. "Synthetic Biomedical Polymers Concepts and Applications" Technomic Publ. Co. ... 

Klraly, R. J. and Hlllegass, D. V., "Polyolefin Blood Pump Components In Synthetic Biomedical Polymers Concept and Applications", Szycher, M., Robinson W. J., Eds., Technomlc Publishing Company, Inc. Westport, 1980, p. 59. 

M. A. Watzky and R.G. Finke, Nanocluster size-control and magic number investigations. Experimental tests of the living-metal polymer concept and of mechanism-based size-control predictions leading to the syntheses of iridium(0) nanoclusters centering about four sequential magic numbers, Chem. Mater., 9, 3083-3095 (1997). 

Strobl, G. R. 2007. The Physics of Polymers Concepts for Understanding Their Structure and Behavior. Berlin Heidelberg Springer-Verlag. 

Strobl, G. (1997). The Physics of polymers. Concepts for Understanding Their Structures and Behavior, Springer, New York, ISBN 978-3-540-25278-8. 

This introductory chapter starts with the basics, assuming the reader is not familiar with polymers, let alone polyethylene. This chapter provides basic information about polymers in general, describes the structure and composition of polyethylene, and explains how UHMWPE differs from other polymers (including high-density polyethylene [HOPE]) and from other materials (e.g., metals and ceramics). The concepts of crystallinity and thermal transitions are introduced at a basic level. Readers familiar with these basic polymer concepts may want to consider skipping ahead to the next chapter. 

The molecular chain architecture of a polymer also imparts many unique attributes, including temperature dependence and rate dependence. Some of these unique properties are further illustrated in the specific case of UHMWPE in subsequent sections of this chapter. For further background on general polymer concepts, the reader is referred to textbooks by Rodriguez (1989) and Young (1983). 

Smith P, Lemstra PJ, Pijpers JPL. Tensile strength of highly oriented polyethylene. II Effect of molecular weight distribution. J Polymer Sci Polym Phys Ed 1982 20 (12) 2229-2241. Stevens PS. Polymer Chemistry An Introduction. 3rd ed. New York Oxford Press 1999. p 234—235. Strobl GR. The Physics of Polymers Concepts for Understanding Their Structures and Behavior. Heidelberg Springer 2007. 

All-cellulosic based composite films can be prepared from either isotropic or anisotropic cellulosic derivatives solutions. However, these composites cannot compete with mechanical properties of cellulose nanofiber reinforced composites. Pioneering studies reported by Favier et al. [35, 36], showed that small amounts of cellulose tunicate whiskers resulted in dramatic improvements in modulus above the glass transititMi temperature of an amorphous polymer matrix, due to the percolation of the cellulose nanofibers. Also recently, a completely new route to cellulose-based composites was proposed by Nishino and Arimoto [37], Soy-keabkaew et al. [38—40], They focused on approaches following self-reinforcing polymer concepts [41, 42] to create composites that often outperform traditional nanofiber reinforced composites [38,40],... 

Polymers configuration and soft and stiff polymer concept... 

Ratner, B. D., Hoffman, A. S. Surface grafted polymers for biomedical applications, in Synthetic Biomedical Polymers Concepts and Applications (eds.) W. J. Robinson and M. Szcher, p. 133, Westport, Connecticut, Technomic PuUishing Co. 1980... 

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