ISSN:
0021-8995
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
A dynamic FT-IR method was used to determine the individual curing temperature ranges of the isoimide-imide isomerization and crosslinking reactions of an acetylene-terminated polyisoimide prepolymer. The individual curing temperature ranges of these two types of chemical reactions for the polyisoimide system using differential scanning calorimetry (DSC) were totally overlapped. Using dynamic FT-IR spectroscopy, the curing temperature ranges of the isomerization and crosslinking reactions were clearly separated. The isomerization reaction began at lower temperatures than the crosslinking reaction and was complete when only half of the crosslinking reaction had occurred. The temperature width, ΔT1/2, was twice as great for the crosslinking reaction compared with the isomerization reaction. Activation energies from dynamic FT-IR spectroscopy can be obtained for the two separate reactions, however, for the reactions considered here, the activation energies were similar, 26 kcal/mol for the isomerization reaction and 23 kcal/mol for the crosslinking reaction. © 1996 John Wiley & Sons, Inc.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
Permalink