Polymer-containing ammonium

Figure 17.7 Char formation in polymer-containing ammonium polyphosphate as flame retardant.

Figure 13. Preparation of immobilized enzymes with different solubilities in aqueous solutions and organic solvents. Procedure A mixture of an enzyme (3 mg) and the polymer (10 mg) was incubated at pH 7.5 for 20 min. Ammonium phosphate (0.1 M, pH 7, 1 mL) was then added to react with the remaining active ester. After 20 min, the solution was ready for use, or lyophilization to give the immobilized enzyme as a powder to be used for reaction in organic solvents. Each gram of the polymer contains approximately 0.7 mmol of the active ester.

Further work on poly(arylene ether phenylimidazole)s led to a series of polymers containing two phenylimidazole units per mer unit (Eq. (5)) [24]. The dihydroxy monomers, 2,2 -(l,3- and l,4-phenylene)bis[(4-phenylhydroxy)-5-phenylimidazole] were prepared from the reaction of iso or terephthaldehyde, 4-hydroxybenzil and ammonium acetate in refluxing acetic acid. High molecular weight polymers as represented in Table 6 were readily prepared in DMAc. 

Although several telechelic polymers of 1,3-dioxolane have been prepared by cationic polymerization, their application is limited due to their susceptibility to acid-catalyzed hydrolysis and/or depolymerization. By termination of living mono- and difunctional poly(l,3-dioxolane) with amines or phosphines, polymers containing one or two stable ionic (ammonium, phosphonium) end groups has been prepared [129,274],... 

The authors determined the amounts of carboxylate anion and carboxylic acid in the polymer by acid-base titration. By assuming the polymer contains an equal number of moles of ammonium cation and carboxylate anion an additional estimate of the number of monomeric units per ammonium ion was obtained. It, twelve, falls between the other two. 

Burning composite propellants containing ammonium perchlorate 615 Butadiene polymers 609.610... 

Blowing agents include azodicarbonamide, azodiisobutyronitrile, etc. Antistatic agents include quaternary ammonium compounds, etc. With the added complexity due to the presence of these compounds, the analysis of polymeric blends and of practical objects made from polymers containing additives is not always simple. 

Oxidation of alcohols. The pernithenate salt is an excellent catalyst for aerobic oxidation of alcohols to aldehydes and ketones in the presence of 4A molecular sieves. The use of a polymer-supported ammonium perruthenat is perhaps an improvement, with good discrimination in the oxidation in favor of primary alcohols. Another versioif specifies a system containing CuCl and 2-aminopyridine also. 

The procedure recommended for amination is that of Pepper et al. (13). Polymers containing quarternary, tertiary, secondary, and primary amines were prepared. In all cases, the dried polymer had to be swelled with a solvent such as THF or dioxane. The amine was then added, which reacted with the chloromethyl groups to produce polymer-bound amine groups. All the steps were carried out under an inert atmosphere. Quaternary ammonium salt groups were obtained by reacting 20 g of polymer swollen in dioxane and 100 ml of cold anhydrous trimethylamine at 0°C. The mixture was kept at 0°C for 2 days with stirring under N . The polymer was then washed sequentially with 2N HC1, 0.1N NaOH, 2N HC1, 2N NaCl, and finally deionized water until the effluent was chloride free. 

Major obstacles faced in the early stage of design of synthetic artificial enzymes were the limited solubility of polymer derivatives in water and the lack of specific binding sites on polymer skeletons. Linear polymers containing quaternary ammonium ions and PEI derivatives are reasonably soluble in water. Without specific binding sites for substrates, however, these polymer derivatives may be simply regarded as polymicelles. 

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