Reactive group content

When multifunctional polymers are used in reactive compatibilization (see Alternatives 2 and 3), their reactive group content (RGC) is expected to influence the extent of the interfacial reaction (at constant blend composition) and the molecular architecture of the in situ formed compatibilizer. For instance, there must be a change from a single graft to a multiple-graft comb-like structure, as the RGC of one of the two reactive polymers is increased. This change in the molecular architecture can affect the stability of the compatibilizer at the interface and its physical entanglement with the chains in the phases to be compatibilized. Finally, the RGC of multifunctional preciu ors may also have an effect on the miscibility with the nonfunctional chains in which they are dispersed. 

The EPR phase contained 50wt% EP-g-MA and the SAN phase contained different amounts of SAN-X of various reactive group contents 0.004 (type a), 0.028 (type b) and 0.049 (type c) mol X/wt % (X being NH2 or carbamate). 

Molecular Complexity. A measure of the combined effects of molecular size, element and functional-group content, internal connectedness, stereocenter content, reactivity, and instability that lead to difficulties of synthesis. 

One might expect that dehydration of a methylol-aducted protein would lead to the formation of Schiff bases, which might be expected to serve as highly reactive groups capable of undergoing further reactions—particularly cross-linking reactions, as the water content of the surrounding solution is reduced. As yet, however, there is little direct evidence that such intermediates are... 

Particularly in the case of dyes with a limited degree of fixation the dyestuff content in the wasted water leads to intensively colored wastewater. As the reactive group of the unfixed dyestuff is hydrolyzed into an inactive form, a reuse is not possible. On the basis of an exhaust dyeing with 5% color depth, a liquor ratio of 1 10, and a degree of dyestuff fixation of 70-80% corresponding to 3.5-4 g/L of dye are fixed on the goods and 1.5-1 g/L of hydrolyzed dyes are released with the dyebath. 

If reactions of the above type occur during extraction, one would expect that gradually less hydrogen exchange takes place as the extraction proceeds because the number of reactive groups decreases. This assumption was tested in the last experiment shown in Table V. The coal was heated for 6 hours at 340°C. with nontritiated phenanthrene prior to extraction with tritiated phenanthrene. When this pretreated coal was extracted, the tritium content of the product was only 15.6% as compared with 21.4%, in the nonpretreated product. This decreased tritium content supports the above assumption and agrees with the proposed reaction mechanism. 

The DMA of the 60/40 DGEBA/PAA system can be seen in Fig. 9. For all systems, the position of the epoxy Tg peak increases with PAA content indicating increased crosslinking of the epoxy due to increased reactive group concentration. The increase in the epoxy Tg could also indicate a miscibility of the polyimide into the epoxy network. 

Recently Uniqema has introduced commercially a Surfmer under the trade name of Maxemul 5011. Maxemul is produced by esterification of an unsaturated fatty anhydride with a methoxy PEG such that the reactive group is close to the hydrophilic moiety [ 34 ]. Stable latexes with a solid content of 52% were produced in the seeded emulsion polymerization of film-forming methyl methacrylate/butyl acrylate/acrylic acid (3% Surfmer on monomers, constant monomer feeding rate over 4 h, potassium persulfate/sodium metabisulfate redox initiator). The latexes were stable to electrolytes but not to freeze-thaw. 

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