Poly aminolysis

Chemistry. Poly(vinyl acetate) can be converted to poly(vinyl alcohol) by transesterification, hydrolysis, or aminolysis. Industrially, the most important reaction is that of transesterification, where a small amount of acid or base is added in catalytic amounts to promote the ester exchange. 

Recently, poly(itaconamide) with 4-tolylcarbamoyl pendant groups have been synthesized in our laboratory. The polymer 9 and copolymers 10 and 11 were synthesized via aminolysis of poly(N-4-methyl-phenylitaconi-... 

Montaudo and co-workers have used direct pyrolysis mass spectrometry (DPMS) to analyse the high-temperature (>500°C) pyrolysis compounds evolved from several condensation polymers, including poly(bisphenol-A-carbonate) [69], poly(ether sulfone) (PES) and poly(phenylene oxide) (PPO) [72] and poly(phenylene sulfide) (PPS) [73]. Additionally, in order to obtain data on the involatile charred residue formed during the isothermal pyrolysis process, the pyrolysis residue was subjected to aminolysis, and then the aminolyzed residue analysed using fast atom bombardment (FAB) MS. During the DPMS measurements, EI-MS scans were made every 3 s continuously over the mass range 10-1,000 Da with an interscan time of 3 s. 

Deacylation rates of acetylsalicylate by isopropylated polymer at pH 7.3 were markedly slower than with unmodified polymer (Table III). With 2.4xlO-2 total residue molar concentration of isopropylated and unmodified poly(ethylenimine), respectively, k2, the pseudo-first-order rate for the former was 1.45 x 10-3 min-1, for the latter 1.2 x 10-1 min-1. Clearly, primary amines are the major sites for aminolysis of aspirin. 

The most recent experimental work to settle the controversy regarding the factor B is the swelling pressure work of Van de Kraats (105,106). This author used poly( >-nitrophenyl methacrylate) gels, cross-linked in solution by aminolysis with hexamethylene diamine. A typical example of his results is shown in Fig. 14, where it is seen that % is a constant over a range in polymer concentration from 5 to 20%. 

Meldal and coworkers developed polyacrylamides cross-linked with poly(ethylene glycol), referred to as PEGA, as supports for solid-phase synthesis and on-bead enzymatic assays [181-183]. Functionalization of the polymer was performed in a similar fashion as in the case of other polyacrylamides, i.e. either by copolymerization with N-acryloylsarcosine ethyl ester followed by aminolysis with ethylenediamine, or by copolymerization with an amino group containing monomer. The monomers used for a high-capacity (0.4-0.8 mmol/g [182]) and a low-capacity (0.2-0.4 mmol/g [181]) PEGA support are sketched in Figure 2.7. 

Aminolysis of poly(dichlorophosphazene) also takes place readily to yield poly(aminophosphazenes) such as 3.32, 3.33, or 3.34.1718 Here too, steric hindrance effects may slow the replacement of the last 25% of the remaining chlorine atoms, thus requiring forcing conditions toward the end of the reaction. 

Markedly different trends in the rate constants appear for aminolysis by lauroyl-poly-ethylenimine (containing 10 residue % lauroyl groups). For each nitrophenyl ester the rate is substantially greater with lauroyl-polyethylenimine than with polymer contain-... 

A clear-cut molecular relay system is materialized with the combination of two nucleophile moieties such as hydroxamic acid and imidazole introduced in a polymer (38, 40, 82). Hydroxamate anion has a high nucleophilicity but deacylation of the acylhydroxamate is very slow. The significance of the deacylation step in the hydrolysis in polymer catalyst is pointed out in several works, for example, the deacylation of acetylated poly(4(5)-vinylimidazole) (83,84) and the aminolysis of nitrophenyl ester of poly(styrene-co-acrylic acid) (85—87). To promote the deacylation velosity of the acylated hydroxamic acid imidazole moiety is introduced in the hydroxamic acid-containing polymer. The polymers are shown in tire following page. 

The mediaiiisin of the melt condensation process (Schemes 1-3) originally was believed to involve straightforward aminolysis of the phenyl ester in the first step, resulting in poly(aniinoamide) formation (segment structure C) with loss of phenol. The second step would then represent a simple qrclodehydration to the imidazole system, water... 

Applying results from low-molecular-weight thiolesters and esters to the corresponding polymers should give slightly slower acid hydrolysis, equally fast alkaline hydrolysis, and a much faster aminolysis of poly-(thiol esters) compared with polyesters (24, 35, 36). 

By chemical recovery of polyester [poly(ethylene terephthalate) (PET)] (Chapter 16) and PU wastes, by alcoholysis or by aminolysis (Chapter 20), new polyols are obtained that can be used in rigid PU foam fabrication. The vegetable oil polyols, obtained by chemical transformation of the double bonds in vegetable oils in various hydroxyl groups are a very attractive route to obtain polyols from renewable resources (Chapter 17). 

CroU, T.I., O Connor, A.J., Stevens, G.W., Cooper-White, J.J., 2004. Controllable surface modification of poly(lactic-co-glycohc acid) (PLGA) by hydrolysis or aminolysis I physical, chemical and theoretical aspects. Biomacromolecues 5, 463—473. 

The sequence distribution and composition of the copolymers generated by melt mixing of blends—such as poly(ethylene terephth te)/poly(ethylene adipate) (PET/PEA) or poly(ethylene terephthalate)/poly(ethylene truxillate) (PET/PETx)— were determined by analysis of the FAB mass spectra of the oligomers present in the crude blends or else formed W appropriate partial degradation (hydrolysis or aminolysis) of the mixtures. ... 

By using active peptide esters with high molecular ester components, inter-molecular aminolysis can be suppressed. — E Glycyl glycine cross-linked poly-(4-hydroxy-3-nitrostyrene) ester hydrobromide suspended in dimethylformamide, neutralized with triethylamine, allowed to stand 12 hrs. at room temp., and the resulting poly-4-hydroxy-3-nitrostyrene removed by filtration diketo-piperazine. Y 75%. F. e. and ester components s. M. Fridkin, A. Patchornik, and E. Katchalski, Am. Soc. 87, 4646 (1965) peptides s. T. Wieland and G. Birr, Ang. Gh. 78, 303 (1966) with active a-aminocarboxylic acid polyphenolesters s. M. Fridkin, A. Patchornik, and E. Katchalski, Am. Soc, 88, 3164 (1966). 

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