Abstract
AbstractThe copolymer system HBA (4‐hydroxybenzoic acid) and HNA (2,6‐hydroxyhaphthoic acid) has been studied mainly by means of differential scanning calorimetry. Heat capacities for the two homopolymers and three copolymers are reported from 175 to 650 K. The heat capacities are additive with composition. The whole copolymer system represents an example of a mesophase intermediate between the liquid‐crystalline and the condis‐crystalline state with a small amount of crystallinity. The disordering transitions (520–620 K) have a eutecticlike phase diagram. The transitions to the isotropic states occur above the decomposition temperatures (600–700 K). The glass transitions (377–434 K) show normal changes in heat capacity (31–34 J/K mol), but are broadened to as much as 200 K.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
