Ethylene glycol structure relationship

A different type of tautomeric relationship exists between compounds of types 323 and 324. Both types of structure can be isolated, pyridones (324, Z = N—Me) and pyrones (324, Z = 0) being formed when 323 (Z = N—Me or 0) is heated with palladium on charcoal in ethylene glycol. Similar isomerizations in the quinol-4-one series have been reported."... 

The relation between SDAs and the zeotype structures they direct is not simply bijective. Usually, the formation of a certain zeotype structure can be directed by more than one SDA [5]. For example, the sodalite structure shown in Fig. 1 can also be directed by molecules other than trioxane, namely, 1,3-dioxolane [15], 1,3-dioxane [16], ethylene glycol [17], ethanolamine [18], and ethylenediamine [18]. Also, depending upon the reaction conditions, an organic molecule may direct the formation of different frameworks [8, 9]. It has therefore been proposed that the term "template", formerly used instead of SDA, should now be reserved for cases of strong structure direction and strong host-guest relationships, in line with its usage in other areas of the natural sciences [5]. A strict condition for a true "template" is that it should not exhibit disorder in the voids of the silica host. 

TA2 Taki, K., Nitta, K., Kihara, S.-I., and Ohshima, M., CO2 foaming of poly(ethylene glycol)/polystyrene blends relationship of the blend morphology, CO2 mass transfer, arrd celltrlar structure, 7. Appl. Polym. Sci., 97, 1899, 2005. 

The structure of homogeneous PHEMA, that is materials polymerized in solutions with less than approximately 45 wt. % water in the reaction mixture 28), has been examined in greater detail. The earliest estimate of pore size in these PHEMA materials was 0.4 nm for a polymer prepared in the presence of water and ethylene glycol was provided by Refojo 29) who used the relationship between water permeability and average pore diameter developed by Ferry 30). The materials investigated by Refojo contained 39 wt. % water. This method was later applied by Haldon and Lee (57) to similar PHEMA samples of 41-42 wt. % hydration to obtain a pore radius between 0.4 and 0.8 nm. It was acknowledged that the assumptions implicit in the use of the Ferry equation resulted in underestimation of the pore size. This was highlighted by the observation that sodium fluorescein, with a radius of 0.55 nm, could readily diffuse into PHEMA. Later Kou et al. 32) demonstrated that solutes of radius 0.6 nm were able to penetrate PHEMA and copolymers of HEMA with methacrylic acid, and that the rate of diffusion was consistent with free volume theory. 

Relationship between the crystal structure of spinel LiMn204 and the heat-treatment temperature when the condensation polymer of citric acid with ethylene glycol is used as a carrier [6]. 

Below, we first consider the shape memory effect, as well as basic structure-property relationships of TPU having crystalline soft segments, e.g., poly(tetra-methylene adipate) glycol (PTAd, M = 2000), and hard segments composed of 4,4 -diphenylmethane diisocyanate (MDI) and ethylene glycol (EG) or ethylene diamine (EDA) [25],... 

One can envision a "worst case" substance of unknown structure which is amorphous, insoluble, and has as one of its principle components a quadrupolar nucleus. The alucones produced by the reaction of diethyMuminume oxide and ethylene glycol fit into diis category. Since the polymers are potential precursors for phase-specific aluminas, die primary structural concern is the relationship between the observed coordination environment present around the aluminum sites in the polymer and the corresponding ceramic (5 - 8). XRPD has shown diat the structures are amorphous there is no crystalinity within the microstructure which would diffract X-rays and (Uvulge hints related to the structure (Fig. 13). 27 1 is a relatively sensitive NMR nucleus, but the polymers are insoluble, and the aluminum nucleus is quadrupolar until recently NMR was all but useless for structural determination of these polymers (Fig. 14). 

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