Synthesis And Characterization Of Novel Poly(Arylene Ether Nitriles)

As a class of special polymer materials, poly(arylene ether nitriles)(PEN) has excellent resistance to heat, mechanical properties, fire resistance, lubricating property and so on, so it has a promising application prospect. In this paper, several novel poly(arylene ether nitriles) polymers were synthesized from two sides, which were introducing ketone group(-CO-) and sulfuryl(-SO2-) to backbone chains of PEN and sulfonic group(-SO3H) and carboxyl(-COOH) to side chains of PEN. In addition, their structure and properties were also studied.1. A series of ketone-containing polyarylene ether nitrile polymers(PEKN) were synthesized via nucleophillic aromatic substitution reaction from 2,6-dichlorobenzonitrile(DCBN), 4,4’-difluorodiphenylketone(DFBP) and bisphenol A(BPA). Their chemical structures and molecular weight were characterized by FTIR, 1H NMR and GPC, respectively. Besides, the solubility, thermal properties and mechanical properties were also investigated. The results indicated that PEKN polymers had good solubility in some common polar organic solvents. PEKN polymers had high heat resistance with the glass transition temperatures in the range of 154~170 °C and good thermal stability with the 5 wt% loss temperatures ranging from 483 °C to 518 °C. PEKN polymers also exhibited good mechanical properties with the tensile strengthin the range of 76~100 MPa.2. A series of sulfone-containing polyarylene ether nitrile polymers(PESN) were synthesized via nucleophillic aromatic substitution reaction from 2,6-dichlorobenzonitrile(DCBN), 4,4’-dichlorodiphenylsulfone(DCDPS) and bisphenol A(BPA). Their chemical structures and molecular weight were characterized by FTIR, 1H NMR and GPC, respectively. The solubility, thermal properties and mechanical properties were also investigated. The results indicated that PESN polymers exhibited good solubility and they can be totally dissolved in some common polar organic solvents at room temperature. PESN polymers had high heat resistance with the glass transition temperatures ranging from 169 °C to 180 °C and good thermal stability with the 5 wt% loss temperatures in the range of 485~508 °C. PESN polymers also showed good mechanical properties and the tensile strength were in the range of 76~100 MPa.3. A series of sulfonated polyarylene ether nitrile polymers(SPEN) were synthesized via nucleophillic aromatic substitution reaction from 2,6-difluorobenzonitrile(DFBN), hydroquinonesulfonic acid potassium salt(SHQ) and bisphenol A(BPA). The membranes in acid form(SPENH) were obtained and their chemical structures were tested by FTIR and 1H NMR. Besides, the inherent viscosities, solubility, thermal properties, mechanical properties, water uptake, ion exchange capacity and proton conductivity were also measured. The results indicated that SPEN polymers showed good solubility in some common polar organic solvents. SPENH polymers had high heat resistance and thermal stability with the glass transition temperatures and 5 wt% loss temperatures in the range of 189~245 °C and 328~378 °C, respectively. SPENH membranes also showed good mechanical properties with the tensile strength of dry and wet membranes in the range of 45~62 MPa and 23~45 MPa, respectively. In addition, SPENH membranes showed good water uptake and proton conductivity at room temperature and 55% RH, which were in the range of 9.7%~57.74% and 2.47×10-5~1.71×10-3 s/cm, respectively.4. A series of sulfonated polyarylene ether nitrile polymers containing carboxyl groups(SPEN-COOH) were synthesized via nucleophillic aromatic substitution reaction from 2,6-difluorobenzonitrile(DFBN), hydroquinonesulfonic acid potassium salt(SHQ) and phenolphthalin(PPL). The membranes in acid form(SPENH-COOH) were obtained and their chemical structures were tested by FTIR and 1H NMR. The inherent viscosities, solubility, thermal properties, fluorescence properties, water uptake, ion exchange capacity and proton conductivity were also measured. The results indicated that SPEN-COOH polymers had good solubility in some common polar organic solvents. SPENH-COOH polymers had high heat resistance and thermal stability, and the glass transition temperatures and 5 wt% loss temperatures are in the range of 151~187 °C and 267~285 °C, respectively. SPENH-COOH polymers also showed good fluorescence properties, and their ultraviolet-visible absorption, fluorescence excitation and emission peaks could be observed obviously. What’s more, SPENH-COOH membranes had high water uptake and proton conductivity at room temperature and 55% RH, and they were in the range of 18.45%~67.86% and 3.4×10-4~3.0×10-3 s/cm, respectively.