Synthesis and characterization of processable heat resistant co-poly(ester-amide)s containing cyclopentylidene moiety

New cyclopentylidene ring-containing diamino-diesters, 1,1-bis(3-aminobenzoyloxy phenyl) cyclopentane, was prepared through reaction of cyclopentanone with two moles of phenol to yield 1,1-bis (4-hydroxy phenyl) cyclopentane (BHPP) (I), the resulting diol (I) on reaction with 3-nitrobenzoyl chloride in N,N-dimethyl acetamide (DMAc) and triethyl amine yield 1,1-bis(3-nitrobenzoyloxy phenyl) cyclopentane (II) which on finally reduced by catalytic hydrogenation in presence of 10% Pd/C in DMAc and stirred at room temperature under a 4 kg/cm² hydrogen pressure yields 1,1-bis(3-aminobenzoyloxy phenyl) cyclopentane (III) (m-BABPP). The structure of novel m-diester-diamine was confirmed by FT-IR, ¹H-NMR and ¹³C-NMR. A series of new m-poly (ester-amide)s and co-poly(ester-amide)s were synthesized by using the solution polycondensation method of novel diamine (III) with IPC and TPC in various mole proportion. These novel polymers were characterized by FTIR spectroscopy, solubility, inherent viscosity and thermal analysis and XRD studies. Inherent viscosities of these polymers were in the range 0.30 to 0.46 dL/g indicating moderate molecular weight built-up. These polymers exhibited excellent solubility in various polar aprotic solvents such as NMP, Pyridine. These polymers were partially soluble in DMSO, DMAc, DMF etc.

X-Ray diffraction pattern of polymers showed that introduction of cardo moiety containing ester linkage would disturb the chain regularity and packing, leading to amorphous nature. Thermal analysis by TGA showed excellent thermal stability of polymers. The structure -property correlation among these poly(ester-amide)s were studied, in view of these polymer's potential applications as processable high temperature resistance materials.