Thermal properties of nylons related to polyglycine

✍ Scribed by A. Xenopoulos; B. Wunderlich; J.A. Subirana

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 767 KB
• Volume: 29
• Category: Article
• ISSN: 0014-3057
• DOI: 10.1016/0014-3057(93)90288-q

✦ Synopsis

Abstraet--Aliphatic polyamides (homopolyamides 1 .n and n.3 and copolyamides 2/n) were characterized in terms of their thermal properties. These series of isomeric polymers have single isolated methylene groups between the amide groups and crystallize in different forms intermediate between pseudohexagonal-and polyglycine II-like. Melting and glass transition temperatures are reported and compared with literature data. Thermogravimetry shows that an isolated methylene group imparts thermal instability to the nylons, depending on the detailed chemical structure. The copolyamides have sharp melting peaks and high crystallinity, when crystallized from solution, but crystallization from the melt is much slower. The heat-flow trends are discussed in relation to estimated heat capacities.