1477664-89-3Relevant academic research and scientific papers
Synthesis of polyisocyanurates by thermal rearrangement of polycyanurates
Tsuchiya, Kousuke,Goto, Eisuke,Ishida, Yoshihito,Higashihara, Tomoya,Kameyama, Atsushi,Ueda, Mitsuru
, p. 692 - 698 (2015)
Polyisocyanurates have been successfully prepared by the thermal rearrangement of polycyanurates, which were obtained from 2,4-dichloro-6-methoxy-1,3,5-triazine and bisphenol monomers. The thermal rearrangement was carried out in the presence of a small amount of tetrabutylammonium bromide (TBAB) as a catalyst at 200°C for 30 or 60 min in an argon atmosphere, and the degree of arrangement was greater than 95%. Transparent and amorphous polyisocyanurate films were obtained and showed a good thermal stability with a 5% weight loss temperature above 340°C in nitrogen and the glass transition temperature above 210°C. Films with a 10-μm thickness exhibited an excellent transparency above 90% at 400 nm. Furthermore, the thermal rearrangement of 2,6-bis(4-methoxyphenyl)-6-methoxy- 1,3,5-triazine to 1,3-bis(4-methoxyphenyl)-5-methyl-1,3,5-triazinane- 2,4,6-trione was investigated in detail. It was found that the complete thermal rearrangement was successfully accomplished in the presence of 2 wt % TBAB at 150°C for 20 min in an argon atmosphere.
Synthesis of transparent and thermally stable polycyanurates and their thermal rearrangement
Saito, Yoshitaka,Matsumoto, Hidetoshi,Higashihara, Tomoya,Ueda, Mitsuru
, p. 3950 - 3955 (2013/09/02)
Transparent and thermally stable polycyanurates, whose solubility can be changed by thermal rearrangement, have been synthesized as functional films used in the multilayer coating process. Before the synthesis of polycyanurates, the model compound, 2,6-bis(4-methoxyphenyl)-6-methoxy-1,3,5-triazine as a cyanurate is prepared and rearranged to an isocyanurate, 1,3-bis(4-methoxyphenyl)-5- methyl-1,3,5-triazinane-2,4,6-trione in an excellent yield by thermal treatment. Based on this result, polycyanurates are prepared by the phase-transfer- catalyzed polycondensation of 2,4-dichloro-6-methoxy-1,3,5-triazine with bisphenol monomers in the presence of quaternary ammonium salts. The polycyanurate obtained from 9,9-bis(hydroxyphenyl)fluorene exhibits a high glass transition temperature at 251°C. The solubility of polycyanurate films containing 1 wt % of tetrabutylammonium bromide can be changed by thermal rearrangement. The partially rearranged films keep high transparency and low birefringence. Copyright
