Water-soluble polymer structural features

It is necessary to discuss another chemical feature related to water-soluble polymers cross-cross-linking — the component that separates viscous systems from gel systems. Viscous systems flow, and it follows, therefore, that they do not possess the tensile properties of muscles. High-viscosity systems have structural integrity, gels provide the necessary combination of tensile strength and elongation or stretch. 

In aqueous solutions of Cm-(EO)n amphiphilic molecules, two interesting features are observed. First, isotropic micellar solutions undergo phase separation on heating. Such behavior is typical of hydrophobic interaction and is also observed for several water-soluble polymers. Hydrophobic interaction results from a change of order in the water structure [54]. Second, at high concentration, liquid crystalline phase behavior is observed with several structures [55]. 

Glass, J. E. (1986). Structural features promoting water solubility in carbohydrate polymers. In Water-Soluble Polymers, Glass, J. E. (Ed.), Advances in Chemistry 213, pp. 3-27. Am. Chem. Soc., Washington, DC. 

Table 2 Structural features of typical water-soluble polymers... 

This chapter covers the applications of Fourier transform infrared (FTIR) and Raman spectroscopy to the characterization of water-soluble polymers. The structural analysis of poly(oxyethylene), poly ethylene glycol), poly methacrylic acid), and poly acrylic acid), and the interactions of selected polymers with solvents and surfactants are presented. Structural features of these compounds in the crystalline and melt states are compared with their structural features upon dissolution in aqueous solvents. Special emphasis is given to the recent studies of the interactions between water-soluble polymers or copolymers and solvents or surfactants. New experimental approaches and the sensitivities of both FTIR and Raman spectroscopy to monitor such interactions are presented. 

Water-soluble macromolecules represent a diverse class of polymers ranging from biopolymers that mediate life processes to synthetic polymers of immense commercial utility. In this article water-soluble polymers have been grouped into the categories biopolymers, nonionic, ionic, and associative, based on key structural features. Recently developed controlled poljunerization techniques imparting important technological features to water-soluble poljuners are also discussed. 

This non-equilibrium chemical and physical (mechanical) state of inhibited plastics is caused by incorporated Cl and their carriers (PI) in concentrations exceeding the thermodynamic compatibility threshold with the polymer. The thermodynamic non-equilibrium is a useful property of inhibited plastics since it expands their anticorrosion functional features. The greater the deviation from the non-equilibrium state of such systems, the quicker the relaxation processes in them accompanied by the release of excess Cl into the ambient medium and to the object being protected. The structure and properties of the components of inhibited plastics Cl depend on their composition and can be carried to the mated part by either diffusion in the gaseous (thanks to Cl volatility) or liquid phase via its exudation, its mixture with a PI, or washing of water-soluble Cl and diffusion through the material moisture. These processes bring about mechanical relaxation of the polymer matrix. The point at which the inhibited anticorrosion material moves into a state of thermodynamic equilibrium is usually correlated with its protective ability. 

A lipid is an organic substance found in living systems that has limited solubility in water but is soluble in organic solvents. Because their classification is based on insolubility in water rather than on a structural feature such as a functional group, lipids vary widely in their structure and, unlike proteins and polysaccharides, are not polymers. Lipids include fats, oils, steroids, and waxes. The predominant lipids are fats and oils, which make up 95% of the lipids in our diet. The other 5% are steroids and several other lipids that are important to ceU function. 

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