The synthesis of poly(1

4-butylene carbonate) (PBC) catalyzed by TiO2-SiO2(PVP-gel) was studied via a two-step melt transesterification of diphenyl carbonate and 1

4-butanediol.After pre-polymerization of diphenyl carbonate and 1

4-butanediol in the standard atmosphere

the vacuum condensation reaction was operated.The PBC was characterized by IR

NMR

GPC and DSC.The experimental results showed that the optimum conditions of the reaction were as follows: the reaction time and reaction temperature were 2 h and 220~230 ℃ (N2 protection)

respectively

in the standard atmosphere pre-polymerization step.The reaction time

reaction pressure and the catalyst dosage were 2 h

300 Pa and 0.15 wt%

respectively

in the vacuum condensation step.The properties of the PBC prepared in optimum conditions

were as follows:[]was 1.12 dL/g

the Mn was 49000

the Mw was 101000

the polydispersity index was 2.07

the Tg was -32.32 ℃

the terminal hydroxyl content was 6.210-4 mol/g and the residue of the phenol was 5.26 wt%.The polymerization degree of PBC can be controlled by the evaporation rate and yield of phenol under the technological conditions.And the phenol by-product was recycled almost completely.