A novel observation in anionic ring-opening polymerization behavior of cyclic carbonates having aromatic substituents

✍ Scribed by Jyuhou Matsuo; Fumio Sanda; Takeshi Endo

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 581 KB
• Volume: 199
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/(sici)1521-3935(19981101)199:11<2489::aid-macp2489>3.0.co;2-v

✦ Synopsis

The anionic ring-opening polymerization of six-membered cyclic carbonates having aromatic substituents, 5-methyl-5-phenyl-l,3-dioxan-2-one (1) and 5,5-diphenyl-1,3-dioxan-2-one (2), was carried out. The anionic homopolymerization of 1 readily proceeds to afford the corresponding polycarbonate, while 2 showed only a slight homopolymerizability. This is due to a rapid back biting reaction of the propagating polymer end to form 2. The conformational restriction of the adduct of 2 with an alkoxide, originating from the electrostatic repulsion between the alkoxide anion and the x electrons of the aromatic rings, might cause the rapid back biting reaction. The anionic copolymerization of 2 with 5,5-dimethyl-1,3-dioxan-2-one (3) proceeds to afford the copolymer. The anionic ring-opening polymerization of 1 was confirmed to be an equilibrium polymerization. Monomer 1 was regenerated up to the equilibrium monomer concentration by depolymenzation of poly(1). A volume expansion (10.8%) was observed during the polymerization of 1.