Figure 2.

(a) Conversion degree, α (%), for the insoluble polymers synthesized according to the reaction conditions shown in Table 1. Above each column is indicated the number of the corresponding polymer. Note that the polymer 2 is included in both series. The conversions for polymers 7 and 9 were calculated using the values obtained in seven independent experiments; for the rest of the polymers, at least three independent syntheses were carried out. (b) Weight balance for the global NH₄CN polymerization reactions indicated in Table 1, according with the following expression: Weigh balance (%) = [(mg gel fraction + mg freeze-dried solution) − (mg NaCN + mg NH₄Cl)]/(mg NaCN + mg NH₄Cl)]·100. (c) Elemental analysis data for the polymers synthetized according to the conditions indicated in Table 1. At least three representative independent samples were measured for each point in the graph; (d) corresponding molar ratios. Note that the %O was calculated by the difference. For the C/O and N/O molar ratios, we considered the %O present in the macrostructure after subtracting this percentage from the water absorbed for the polymers as moisture, which was about ~10% for all of the samples. This amount of water was estimated by the TG data discussed below.