Report on Alkoxyl Determinations

Determination of etherification levels in acrylamide interpolymers using alcohol exchange-gas chromatographic techniques

“…In this connection it has been stressed (4) that the relatively large amount of -4Na and l-K present in irradiated natural water, besides preventing the measurement of many elements instrumentally, also limits the sample size and increases the counting times necessary for other elements. In a recent review paper (7), the determination of Ag, Br, Cl, Co, Cr, Cs, Fe, Mn, Na, Rb, Sb, Sc, Se, U, Zn, and occasionally Hg in fresh water by instrumental neutron activation analysis is stated to be possible if several optimal decay times (e.g., 4 hours, 3 and 20 days) before counting are included in the scheme. Schmitz et al (S) suggest, however, that a higher number of elements may be determined if freeze-drying is introduced as a preconcentration step.…”

“…An alcohol exchange procedure in conjunction with gas chromatography has been presented to determine the etherifying alcohols in methylolated melamines (5). The Zeisel reaction has been extensively studied and has been used successfully for the determination of alkoxyl groups in cellulosic materials (6)(7)(8). Quantitative cleavage of the alkoxy groups in polymers is routinely obtained; however, hydriodic acid also cleaves any ester linkages on the polymer backbone, giving a positive interference (9).…”

Report on Recommended Specifications for Microchemical Apparatus. Alkoxyl

“…Recommended specifications for an apparatus for the determination of alkoxyl groups were delayed until a collaborative study (10,11,18) of methods for this determination had been conducted by the Association of Official Agricultural Chemists. In this study, compounds representing ethyl and methyl esters and ethers were submitted to practicing microchemists, who had expressed their willingness to cooperate. These individuals were asked to analyze the samples by whatever methods they were using in their ow7n laboratories and to furnish detailed information on the procedure and apparatus.…”

Organic Microchemistry

“…This was replaced by 25% sodium acetate with a considerable improvement in results, especially when ethoxyl groups were determined. In two collaborative studies reported by Steyermark (50,53), analysts using the Clark method obtained better results than those using the Elek procedure. Methoxyl and ethoxyl ethers and esters were determined.…”