Premium
Elastic moduli of liquid crystalline copolymers
Author(s) -
Jawad S. Abdul
Publication year - 1994
Publication title -
polymer international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.592
H-Index - 105
eISSN - 1097-0126
pISSN - 0959-8103
DOI - 10.1002/pi.1994.210330405
Subject(s) - thermotropic crystal , materials science , copolymer , composite material , ultimate tensile strength , shear modulus , elastic modulus , modulus , young's modulus , liquid crystalline , bulk modulus , polymer
Dynamic tensile and shear moduli measurements have been carried out on highly oriented thermotropic liquid crystalline copolymers formed by random copolymerization of 2‐hydroxy‐6‐naphthoic acid, terephthalic acid and p ‐aminophenol. This liquid crystalline copolymer is known as HNATA. Application of the aggregate model of units of structure gives rise to an estimation of the orientation angle θ = 5° and a chain modulus E c = 230 GPa. The fall in tensile modulus with increasing temperature is related to two factors: a decrease in the intrinsic chain modulus and a reduction in the shear modulus.