摘要
采用示差扫描量热法、应力应变测量研究了物理老化对非晶态聚对苯二甲酸乙二酯（ＰＥＴ）膜单轴拉伸过程中应力屈服行为的影响．结果表明，非晶高聚物经物理老化后屈服应力，应力屈服峰及热焓吸热峰均增大；屈服前后的ＤＳＣ结果表明，经过屈服点后试样热焓吸热峰消失，屈服后的试样经物理老化后，应力屈服峰又再现．从凝聚缠结的观点解释了非晶高聚物物理老化和应力屈服的本质．
ffects of physical ageing on the yield behavior during uni-axial stretching of amorphous PET film were studied by differential scanning calorimetry and stress-strain measurements. It was shown that the endothermic peak at Tg, the yield stress, and the stress yield peak in the stress-strain curve all increased as physical ageing progressed. On passing through the yield point, DSC indicated that theendothechc peak disappeared. Post-yield amorphous film followed by further heat treatngllt below Tg, a yield stress peak in the stress-strain curve was shown again during re-stretching. The nature of the physical ageing and stress yield were explained on the basis of cohesional entanglements.
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
1996年第4期475-479,共5页
Acta Polymerica Sinica
基金
国家重大基础研究项目
"高分子凝聚态的基本物理问题研究"资助
关键词
物理老化
应力屈服
PET
示差扫描量热法
DSC, Physical ageing, Stress yield, Endothermic peak, Cohesional entanglement
