摘要
The effect of temperature on the characteristic of Fourier Transform Infrared(FTIR),the dependence of the average molecular weight and the polydispersity on the annealing temperature and the relationship between linear expansion coefficients and temperature of poly(propylene carbonate) end-capped with maleic anhydride(MA-PPC) were investigated.The vibration peak of hydroxyl group at 1714?cm -1 in the FTIR spectra,which belongs to the carboxyl end-group in MA-PPC,decreases with increasing the temperature of the sample and it disappeared totally when the sample was heated over 70℃.The average molecular weight of MA-PPC almost doubled when the sample was annealed at 110～150℃ for 30 min,however the polydispersity was maintained roughly.A new relaxation transition at about 80℃ was detected on the curve of the linear expansion coefficient versus temperature that is the characteristic of macromolecular coupling or crosslinking reaction.These results confirmed that the macromolecular coupling reaction was carried out between the end carboxyl groups of MA-PPC when the sample was heated over 70℃.
The effect of temperature on the characteristic of Fourier Transform Infrared( FTIR), the dependence of the average molecular weight and the polydispersity on the annealing temperature and the relationship between linear expansion coefficients and temperature of poly(propylene carbonate) end-capped with maleic anhydride( MA-PPC) were investigated. The vibration peak of hydroxyl group at 1714 cm(-1) in the FTIR spectra, which belongs to the carboxyl end-group in MA-PPC, decreases with increasing the temperature of the sample and it disappeared totally when the sample was heated over 70degreesC The average molecular weight of MA-PPC almost doubled when the sample was annealed at 110 similar to 150degreesC for 30 min, however the polydispersity was maintained roughly. A new relaxation transition at about 80degreesC was detected on the curve of the linear expansion coefficient versus temperature that is the characteristic of macromolecular coupling or crosslinking reaction. These results confirmed that the macromolecular coupling reaction was carried out between the end carboxyl groups of MA-PPC when the sample was heated over 70degreesC.
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
2003年第6期895-898,共4页
Acta Polymerica Sinica
基金
国家 973课题 (项目号G19990 64 80 6)
