Synthesis of semicrystalline poly(guanamine)s based on 2-substituted-4,6-dichloro-1,3,5-triazine with α, ω-alkylene diamines, and the formation of cyclic tetramers

Abstract Polycondensation of various 2-substituted-4,6-dichloro-1,3,5-triazine such as N , N -diphenylamino (DCPT), benzylamino (BnDCT) substituents with α, ω - alkylene diamines including hexamethylene (HMDA), octamethylene (OcDA), decamethylene (DcDA), and dodecamethylene diamine (DdDA) was performed, and the resultant polymers were analyzed. Two-phase polymerization in nitrobenzene/aqueous NaHCO 3 at 100 °C resulted in a high molecular weight (MW) polymer ( M n  = 12,400) with a small fraction (26.7 wt%) of low MW oligomer, whose main component was confirmed as a 4-membered cyclic compound. Polymers prepared with HMDA were crystalline with poor solubility, whereas those with OcDA, DcDA, and DdDA were all amorphous with high MWs ( M n  = 40,000–60,000) and good solubility enough to prepare the self-standing transparent films. The polymers show moderate glass transition temperatures from 76 °C to 159 °C. In differential scanning calorimetry measurements, only poly(BnDCT-HMDA) showed a clear endothermic peak ( Δ H = 119 J/g), which corresponds to melting at 220 °C.