TY - JOUR
T1 - A new study of glass transition of polymers by high pressure DSC
AU - Mi, Yongli
AU - Zheng, Sixun
PY - 1998/6/1
Y1 - 1998/6/1
N2 - The glass transition temperatures of polycarbonate (PC) were measured by means of high pressure DSC in He, N2, and CO2 atmospheres. It was found that the glass transition temperature (Tg) of PC was independent in He with pressure up to 70 atm, whereas the Tg of PC shifted by 6° towards the lower temperature end in N2 atmosphere when the pressure was 70 atm. The depression in Tg by high pressure CO2 was found to be even more remarkable due to a stronger plasticization effect. It was also found that the glass transition for PC/CO2 system exhibited an endothermic peak. It was believed that the endothermic behaviour resulted from the excessive desorption of the absorbed gas at Tg due to the increase in chain mobility. This conclusion was further confirmed by examining the glass transition behaviour of poly(vinyl benzoate) in CO2 at 2 atm.
AB - The glass transition temperatures of polycarbonate (PC) were measured by means of high pressure DSC in He, N2, and CO2 atmospheres. It was found that the glass transition temperature (Tg) of PC was independent in He with pressure up to 70 atm, whereas the Tg of PC shifted by 6° towards the lower temperature end in N2 atmosphere when the pressure was 70 atm. The depression in Tg by high pressure CO2 was found to be even more remarkable due to a stronger plasticization effect. It was also found that the glass transition for PC/CO2 system exhibited an endothermic peak. It was believed that the endothermic behaviour resulted from the excessive desorption of the absorbed gas at Tg due to the increase in chain mobility. This conclusion was further confirmed by examining the glass transition behaviour of poly(vinyl benzoate) in CO2 at 2 atm.
KW - Glass transition temperatures
KW - High pressure DSC
UR - https://www.webofscience.com/wos/woscc/full-record/WOS:000073915000014
UR - https://openalex.org/W2042314972
UR - https://www.scopus.com/pages/publications/0032124163
U2 - 10.1016/S0032-3861(97)10357-3
DO - 10.1016/S0032-3861(97)10357-3
M3 - Journal Article
SN - 0032-3861
VL - 39
SP - 3709
EP - 3712
JO - Polymer
JF - Polymer
IS - 16
ER -