聚尿酯/聚苯乙烯--環己烷溶液之研究

The Study of Polyurethanes/Polystyrene-Cyclohexane Solution

宋耀明(Song, Yaw Min)

指導教授 ： 余子隆

元智大學/工程學院/化學工程與材料科學學系/碩士(1995年)

摘要

無資料

關鍵字

示差掃描熱卡計 ； 熱重分析儀 ； 小角度X-ray掃描儀

並列摘要

Polyurethanes were synthesized from polyester and butanediol
with three different diisocyanates, i.e. 4,4'-diphenylmethane
diisocyanate(MDI), m-xylene diisocyanate(XDI), and 2,4-toluene
diisocyanate(TDI). The effect of chemical structures of
diisocyanate compounds on the degree of crystallinity and the
thermal stability were observed. Differential scanning
calorimetry(DSC) and small angle X-ray scattering(SAXS) were
used to determine the degree of crystallinity of hard segment.
The thermal degradation of polyurethanes was studied by
thermogravimetric methodIt has been shown that the polyurethane
hard-segment crystallinity decreases in the following order MDI.
XDI.TDI. The experimental results also indicated that
polyurethanes with aralkyl diisocyanates, i.e. XDI, had best
thermal stability. The polyurethanes synthesized from aromatic
diisocyanates,i.e. MDI and TDI had worse thermal stability than
from XDI. However, owing to the higher degree of hard-segment
crystallinity for polyurethanes based on TDI.

並列關鍵字

DSC ； TGA ； SAXS