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Poshkus, A. C.

Publications and source records attributed to Poshkus, A. C..

6 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1985

Synthesis of 2,4,8,10-tetroxaspiro5,5undecane

Pentaerythritol is converted to its diformal, 2,4,8,10-tetroxaspirol5.5undecane, by heating it to a temperature within the range of about 110 to 150 C, for a period of up to 10 minutes, in the presence of a slight excess of paraformaldehyde and of a catalytic quantity of an acid catalyst such as sulfuric acid. The reaction may be carried out in two steps, by forming first the monoformal, then the diformal. In any case, total reaction time is about 10 minutes, and yield of diformal are greater than 90%. Previous processes require hours or days, and often, tedious operating procedures.

Poshkus, A. C.↗
NASA NTRS1981

Synthesis of polyformals

Formals of CH2OH(CHOH) sub n CH2OH polyols (n = 2 to 4) are prepared in less than 15 minutes by heating to about 125 C, a mixture of e.g. sorbitol and paraformaldehyde in slight excess (5 to 10%), in the presence of e.g. sulfuric acid in catalytic quantities. Elution with methanol and filtration yield the pure solid cyclic triformal. The process can be carried in stages, using almost stoichiometric quantities of paraformaldehyde, but without any change in overall heating time.

Poshkus, A. C.↗
NASA NTRS1980

Improved synthesis of polyformals

Polyformals are prepared in less than 15 min. as opposed to hours or days by conventional processes. Product can be converted into ethylencially unsaturated monomers and into aphrogenic and pyrostatic phosphorylated derivatives and the like.

Poshkus, A. C.↗
NASA NTRS1980

Synthesis of 2, 4, 8, 10-tetroxaspiro (5.5) undecane

Method drastically reduces preparation time pentaerythritol diformal from several hours to time span of 3 to 20 minutes with yields greater than 90 percent. Other advantages include elimination of solvents, decrease in labor and energy needs, adaptability to continuous operations, and overall simplicity and convenience.

Poshkus, A. C.↗
NASA NTRS1979

An improved synthesis of 2,4,8,10-tetroxaspiro /5.5/ undecane /pentaerythritol diformal/

It is found that high yields of pentaerythritol diformal can be prepared in less than 10 minutes by heating a stirred mixture of pentaerythritol with a slight excess of paraformaldehyde up to about 120 C in the presence of catalic amounts of acid, but without any solvents or with only a small amount of water. The reaction was carried out in two stages: first by preparing the monoformal with a molar equivalent of paraformaldehyde in about five minutes, and then, after cooling to about 70 C, adding the remainder of paraformaldehyde in 1% excess, and heating to about 120 C for a total heating time of 10 minutes

Poshkus, A. C.↗