Dispersants general structure

Fig. 8. General structures of polymeric dispersants (a) liomopolymer, (b) random copolymer, (c) diblock copolymer, and (d) comb polymer, where A = anchor group, B = soluble repeat unit, and C = repeat unit with solubility different from B. The repeat units may occur in sequences hundreds of...

The dispersion polymerization of alkylcyanoacry-lates provides degradable uniform polyalkylcyanoacry-late latex particles in submicron size range. These particles are termed as biodegradable nanoparticles in the common literature [102-107]. The general structure of alkylcyanoacrylates is ... 

The general structure of this class of materials can, therefore, be summarized as a fine dispersion of metal oxide in a polymer matrix very similar to plasma polytetrafluoroethylene and in principle any metal should be able to be incorporated. Clearly, if the films are protected from the atmosphere, for metals which form involatile fluorides having a relatively weak metal-fluorine bond strength, it should be possible to produce films having metal atoms dispersed in the matrix. It is expected that these films will have many interesting chemical, optical, electrical and magnetic properties., ... 

The next logical step toward chromophore design was to conduct a spectral survey of commercially available organic compounds in order to learn some general structure-property relationships for minimization of the residual absorbance. As an easily measured figure of merit, the ratio between the minimum and maximum molar absorptivities has been used. In many cases, this ratio (expressed in percent, or more conveniently, as the minimum molar absorptivity per 100,000 L/mol-cm of maximum absorbance) is 5-10% (5000-10,000 per 100,000). (The lower the number the better the dye.) An improved figure of merit would take into account the area under the absorption curve as well as the location of the transparent window relative to the peak in the absorption. This is tantamount to calculating the dispersion from the absorption spectrum, which was too complex for this type of survey. 

Azo dyes are by far the largest family of organic dyes. They play a prominent role in acid, direct, reactive, azoic, and disperse dye structures, as shown previously, and include structures that cover the full color spectrum. Generally, the synthesis of azo dyes involves a process known as diazo coupling. In this... 

Fig. 8.11. General structure of a polyurethane used in the preparation of emulsions and aqueous dispersions.

In the A/Q series disperse dyes of the general structure of Figure 2.73 are blues of good properties in PES. 

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