Synthesis of polyetherols from melamine and ethylene carbonate

Abstract

Attempts to synthesize s-triazine ring containing polyetherols from melamine and ethylene carbonate are described. The conditions of synthesis providing optimal yields of the polyetherols were 165°C, melamine to ethylene carbonate molar ratio 1 : 9 to 1 : 18, and 4 g of potassium carbonate or diazabicyclo[2.2.2]octane catalyst per mole of melamine. The structure of the products was established by 1 H-NMR and IR spectroscopy. The kind and amount of side products [mostly poly(ethylene glycols)] was determined by GLC. The polyetherols have been found useful in the synthesis of polyurethanes of improved thermal stability.

Oligoetherols and polyurethane foams obtained from metasilicic acid

“…In separate control experiments the products of EC with reference diols like glycol and polyglycols were analyzed chromatographically (Table 1). It has been found that the percentage of glycols and their consecutive products did not exceed 20 mass % in the products (Table 3), which is comparable to that found previously in case of melamineethylene carbonate system [31]. The presence of low molecular products in oligoetherol corroborates well with hydroxyl number (Table 2) which is 806.8 mg KOH/g, i.e., higher than the theoretical (602.6 mg KOH/g).…”

Polyetherols from isocyanuric acid and propylene carbonate

“…Calibration curves for the chromatographic determinations (glycols and polyglycols) were used as described in the literature. 8 The reference substances were propane-1,2-diol, 4-oxaheptane-2,6-diol (OHD), 2-methyl-3-oxahexane-1,5-diol (MOHD), and 5-methyl-4,7-dioxadecane-2,9-diol (MDODD).…”

“…Also, IA slowly dissolved in PC within 35 h. The solid admixture was also present when mixtures of catalysts were used. Therefore, other catalysts were eventually chosen, including DABCO and TBAH (Table I, syntheses 5-9), which were successfully used before for the reactions of alkylene carbonates with melamine 8 and uric acid. 10 These catalysts allowed us to avoid the formation of solid admixtures, resulted in shorter procedures, and last, but not least, were cheaper.…”

Reactions of adenine with ethylene oxide and propylene oxide

“…Evidently, a more effective catalyst was needed. Basing on experience from studies on melamine oxyalkylation, 9 DABCO was selected as a catalyst. This catalyst used in DMF solution proved to be more effective than TEA.…”