Synthesis and Characterization of New Soluble Polyamides Derived from 3,3',5,5'-Tetramethyl-2,2-bis[4-(4-carboxyphenoxy)phenyl]propane

摘要

A series of new soluble polyamides having isporopylidene and methylsubstituted arylene ether moieties in the polymer chain were prepared by the direct polycondensation of 3,3',5,5'-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~(-1) while the weight-average molecular weigth and number-average molecular weight were in the range of 86,700-259,000 and 43,300-119,000, respectively. All the polymers were radily dissolved in polar aprotic solvents such as NMP, N,N-dimethylacetamide, and N,N-dimethylform-amides, as well as less polar solvents such as m-cresol and pyridine, and even solbule 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 233-260degC and 10% weight loss temperatures in the range of 450-489 and 459-493degC in nitrogen and air atmosphere, respectively.