AGING CHARACTERISTICS OF ORIENTED POLY(ETHYLENE-TEREPHTHALATE)

被引:32
作者
MUKHERJEE, S
JABARIN, SA
机构
[1] UNIV TOLEDO,COLL ENGN,DEPT CHEM ENGN,TOLEDO,OH 43606
[2] UNIV TOLEDO,COLL ENGN,INST POLYMER,TOLEDO,OH 43606
关键词
D O I
10.1002/pen.760351404
中图分类号
TQ [化学工业];
学科分类号
0817 ;
摘要
The physical aging characteristics of oriented poly(ethylene terephthalate (PET), have been studied as functions of storage time and temperature below the glass transition temperature (T-g) of PET. The free volume relaxation, associated with aging, has been characterized by the enthalpy of relaxation at T-g, as measured by differential scanning calorimetry. The effects of the free volume relaxation on mechanical properties and the mode of failure have been investigated. It has been determined that a correlation exists between the enthalpy of relaxation and the ductile-to-brittle failure transition. Molecular orientation reduces significantly the enthalpy of relaxation, resulting in the disappearance of the ductile-to-brittle transition when highly oriented samples are aged over time. It has been established that a minimum amount of orientation is required to reduce or eliminate the effects of PET aging. Molecular orientation has also been found to reduce craze formation when oriented PET is exposed to a stress-cracking medium at a constant stress.
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页码:1145 / 1154
页数:10
相关论文
共 28 条
[2]  
AKLONIS JJ, 1983, INTRO POLYM VISCOELA, pCH3
[3]   THE EFFECT OF PHYSICAL AGING ON THE PROPERTIES OF POLY(ETHYLENE-TEREPHTHALATE) [J].
AREFAZAR, A ;
BIDDLESTONE, F ;
HAY, JN ;
HAWARD, RN .
POLYMER, 1983, 24 (10) :1245-1251
[4]   PHYSICAL AGING IN GLASSY-POLYMERS - AN IR SPECTROSCOPIC INVESTIGATION OF POLY(ETHYLENE-TEREPHTHALATE) [J].
AREFAZAR, A ;
HAY, JN .
POLYMER, 1982, 23 (08) :1129-1132
[5]   NON EQUILIBRIUM ANNEALING BEHAVIOR OF POLYVINYL ACETATE) [J].
BAIR, HE ;
JOHNSON, GE ;
ANDERSON, EW ;
MATSUOKA, S .
POLYMER ENGINEERING AND SCIENCE, 1981, 21 (14) :930-935
[6]  
BUNN CW, 1954, P ROY SOC LOND A MAT, V226, P531
[7]  
DOOLITTLE AK, 1981, J APPL PHYS, V22, P1471
[8]  
FERRY JD, 1971, VISCOELASTIC PROPERT
[9]  
FISCHER EW, 1976, J MATER SCI, V11, P1041, DOI 10.1007/BF02396639
[10]  
ILLERS KH, 1969, MAKROMOLEKUL CHEM, V127, P1