Synthesis and characterization of new soluble polyamides derived from 3,3′,5,5′‐tetramethyl‐2,2‐bis[4‐(4‐carboxyphenoxy)phenyl]propane

Abstract

A series of new soluble polyamides having isopropylidene and methylsubstituted arylene ether moieties in the polymer chain were prepared by the direct polycondensation of 3,3Ј,5,5Ј-tetramethyl-2,2-bis[4-(4-carboxyphenoxy)phenyl]propane and various diamines in N-methyl-2-pyrrolidinone (NMP) containing CaCl 2 using triphenyl phosphite and pyridine as condensing agents. Polymers were produced with moderate to high inherent viscosities of 0.85-1.47 dL g Ϫ1 while the weight-average molecular weight and number-average molecular weight were in the range of 86,700 -259,000 and 43,300 -119,000, respectively. All the polymers were readily dissolved in polar aprotic solvents such as NMP, N,N-dimethylacetamide, and N,N-dimethylformamide, as well as less polar solvents such as m-cresol and pyridine, and even soluble in tetrahydrofuran. These polymers were solution-cast into transparent, flexible and tough films. All of the polymers were amorphous and the polyamide films had a tensile strength range of 82-122 MPa, an elongation at break range of 6 -18%, and a tensile modulus range of 2.0 -2.8 GPa. These polyamides had glass transition temperatures between 233-260°C and 10% weight loss temperatures in the range of 450 -489 and 459 -493°C in nitrogen and air atmosphere, respectively.

Nonfluorinated copolymerized polyimide thin films with ultralow dielectric constants

“…In the same way, with the increasing of the rigid fluorene groups, PI‐2 possessed the highest static T g 16. Also, there were various factors, such as the shape and the way of piling, that could have led to the irregular char yield results in nitrogen 17…”

Facile preparation and characterization of soluble aramid

“…However, these approaches mentioned above have some drawbacks. For example, flexible groups usually decrease the thermal stability of the polymers . We previously prepared a soluble, thermally stable aramid with a bulky pendant group; however, the synthesis was relatively complex .…”

Synthesis of new fluorinated aromatic poly (ether ketone amide)s containing cardo structures by a heterogeneous palladium‐catalyzed carbonylative polycondensation

“…So far, considerable efforts have been made to improve their processability and dielectric performance without much sacrificing their high thermal stability. The successful strategies employed with those purposes include the introduction of flexible linkages, bulky pendant or cardo groups, and unsymmetrical or noncoplanar structures into the polymer backbone.…”