Synthesis and properties of 4,4?-biphenyldicarboxylic acid and 2,6-naphthalenedicarboxylic acid

Abstract

This article describes the synthesis and the properties of polyesters and copolyesters prepared from ethylene glycol, terephthalic acid, 4,4′ biphenyldicarboxylic acid (BDA), and 2,6‐naphthlenedicarboxylic acid (NDA). The effect of incorporating varying levels of BDA and NDA on polyethylene terephthalate (PET) is described. Depending on the concentration, incorporation of BDA into PET leads to an improvement in glass transition temperature (Tg), strength, modulus, and barrier properties. Copolymers of PET containing up to about 50% BDA derived units are clear and have Tg's ranging from 85 to 105°C, making them suitable for applications where a high Tg along with clarity is important. Copolymers with higher BDA concentration are highly crystalline, with high rates of crystallization from the melt. Copolymerization of NDA with oligoethyleneterephthalate leads to copolymers that are generally amorphous. Crystallinity can be developed in copolymers with low concentration of NDA by thermal annealing. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3139–3146, 1999

Oxygen‐barrier properties of copolymers based on ethylene terephthalate

“…In contrast, copolymerization with the symmetrical linear isomer, 4,4′BB, produced a substantial increase in P . This was contrary to a previous report of a substantial decrease in the permeability of PET‐4,4′BB copolymers,16 possibly reflecting a significant orientation effect with the rigid‐rod comonomer. Qualitatively, changes in diffusivity paralleled changes in permeability [see Fig.…”

UV-Blocking Synthetic Biopolymer from Biomass-Based Bifuran Diester and Ethylene Glycol

“…The homologous biaryl, 4,4′-biphenyldicarboxylic acid (BDA), on the other hand, is useful for enhancing the properties of PET. 21 The copolyesters are more suitable for high-temperature, high-performance applications. Over the years, BDA has regularly appeared in patent applications related to polyesters.…”

A kinked unit‐containing thermotropic liquid crystalline copolyester with low glass transition temperature and broad phase transition temperature

“…However, the introduction of ethanediol groups could deteriorate the thermal stability and the flame‐retardant effectiveness of P‐TLCP for polymer matrix. There also are some other methods to low down mesophase temperature and T m , such as the use of nonsymmetrical substituents,1, 11, 12 the introduction of nonlinear or bent monomers,13–15 replacement of ester groups with ether groups,16, 17 the use of mesogenic groups based on conformational isomenism,18–20 hyperbranched topologies,21, 22 dendritic architectures23 and copolymerization with different monomers 24…”