S P P kAcid-and tmse-catalyzed polymem involving sulfamide, melamine, and formaldehydeThe products are insoluble and their thermal have been prepared and investigated. stability does not exceed 225OC. in N2.The preparation of polymers by condensation of sulfamide, melamine, and formaldehyde was described in Part 1.l Samples of the more promising materials were synthesized for structure and evaluation purposes. The results of this investigation, as well as the results of additional studies on the related sulfamide-formaldehyde 1 :4 polymers, are discussed. (Here and throughout this paper 1:4, etc., indicates the molar ratio of reactants.) Data on solubility, thermal stability, infrared and x-ray structure analysis of these materials are included.
EXPERIMENTALSome of the more promising compositions described in Part I' were selected for evaluation, and their preparations were also examined somewhat more closely than previously.
PreparationsAcid-Catalyzed Sulfamide-Melamine-Formaldehyde 1 : 1 :4 (IA). (Prep aration 10, Table I, Part I.) A mixture of 6.0 g. (62.4 mmoles) of sulfamide, 7.8 g. (62.4 mmoles) of melamine, 20.4 g. of 37% aqueous formaldehyde solution [7.54 g. (249 mmoles) CH,O], and 4.5 ml. of O.558N hydrochloric acid (2.51 mmoles) was refluxed for 1 hr. at about 85" C. The pH of the resulting suspension was 2. Two phases remained throughout the course of the reaction. The product was a porous, tough, white solid, which was powdered and washed with 133 ml. of water, filtered, 489 490 FLORENTINE Er AI,.and then dried for 18 hr. a t 70°C. product obtained weighed 17.2 g. 100 ml. of water, filtered hot, and dried to constant weight, 15.3 g. a melting point of 27.5-280°C. (decomposes with red foaming).