Preparation and properties of polycarbodiimides

✍ Scribed by L. M. Alberino; W. J. Farrissey JR.; A. A. R. Sayigh

• Publisher: John Wiley and Sons
• Year: 1977
• Tongue: English
• Weight: 464 KB
• Volume: 21
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.1977.070210726

✦ Synopsis

Abstract

A series of polycarbodiimides was prepared from isocyanates using 1‐phenyl‐3‐methyl‐2‐phospholene‐1 oxide as catalyst. The molecular weight of the series was varied by employing controlled amounts of phenyl isocyanate as a terminating agent. The resultant polymers showed improved processing over very high molecular weight unterminated polymer, while still maintaining good thermal stability and equivalent mechanical properties. A study of the viscoelastic properties of these polymers using modulus–temperature plots showed that the materials underwent a crosslinking reaction at elevated temperatures (200–250°C). These reactions could be explained on the basis of a model, diphenylarbodiimide, and most likely include the formation of carbodiimide dimers and trimers.