Synthesis and thermochemistry of phenylmaleimide- and phenylnadimide-terminated bisphenol A polycarbonates

✍ Scribed by M. J. Marks; D. C. Scott; B. R. Guilbeaux; S. E. Bales

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 593 KB
• Volume: 35
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(19970130)35:2<385::aid-pola22>3.0.co;2-k

✦ Synopsis

Phenylmaleimide (PMI)-and phenylnadimide (PNI)-terminated bisphenol A polycarbonates (PCs) were prepared by solution or interracial phosgenation processes, and their thermal crosslinking, both with and without a free radical initiator, and the thermal stability of the resultant network polymers were investigated. rn-PMI PCs were prepared by interracial phosgenation of bisphenol A and rn-hydroxypheny lmaleimide, but p-hydroxyphenylmaleimide caused rapid phosgene hydrolysis under interracial conditions and PCs from it could only be made by solution phosgenation. The degree of crosslinking of PM1 PCs, as measured by their gel fraction, heated in the absence of a free radical initiator was generally higher at 250°C than at 300°C and increased with the concentration of PMI end groups. m-and p-PM I PCS form thermoses having nearly complete gel fractions by radical initiated curing at 150-200"C. The gel fraction of these thermoses decreases with exposure to higher temperatures (300"C). This behavior is attributed to BA PC chain degradation induced by nitrogen-containing maleimide reaction products. p-PNI PC was prepared by solution phosgenation and the thermal reaction of it in the presence of the initiator produced only a small increase in molecular weight.