A new fluorinated poly(ether amide) bearing xanthene group

A new fluorinated poly(ether amide) bearing xanthene group was prepared from 9,9-bis[4-(2-trifluoromethyl-4-aminophenoxy)phenyl]xanthene (BTFAPX) with 9,9-bis[4-(4-carboxyphenoxy)phenyl]xanthene (BCAPX) in the presence of triphenyl phosphate and pyridine (Py). The polymer had the weight-average molecular weight (Mw) of 69,000 and number-average molecular weight (Mn) of 39,000, showed the glass transition temperature (Tg) of 267 °C, 5% weight loss temperature (Td5) over 460 °C both in N2 and air, and char yield of 62% at 800 °C in N2. This polymer was amorphous and readily soluble in amide-type solvents such as N,N-dimethylacetamide (DMAc), and even in m-cressol, Py and tetrahydrofuran (THF) at room temperature, and exhibited tensile strength of 74 MPa, elongation at break of 6%, tensile moduli of 2.2 GPa. The polymer had low dielectric constant of 3.69 (100 Hz), low moisture absorption of 0.56%, and high transparency with an ultraviolet–visible absorption cut-off wavelength at 334 nm.