Young-Taik Hong

Synthesis of a novel poly(aryl ether) with pendent N-phenylimide groups

A novel monomer with two N-phenylimide activating groups for the preparation of poly(aryl ether)s was investigated. A poly(aryl ether) was prepared by nucleophilic halide displacement from an aromatic dihalide monomer containing two N-phenylimide groups by sodium salts of bisphenol A. The monomers and the resulting polymer were characterized by FT-IR and 1H NMR spectroscopy, elemental analysis and differential scanning calorimetry (DSC). The prepared polymer with a molecular weight of 6 300 and a polydispersity of 1.37 determined by GPC is readily soluble in polar aprotic solvents, e. g. dimethylformamide (DMF), dimethylacetamide (DMAc), dimethylsulfoxide (DMSO), and N-methyl-2-pyrrolidone (NMP). Despite the low molecular weight the polymer is thermally stable up to 390°C and has a glass transition temperature of 218°C which is identical to that of ULTEM® poly(ether imide).

Synthesis and characterization of new poly(amide imide)s by direct polycondensation of diamine containing diimide group and diacids using thionyl chloride

A diimide diamine (DIDA) monomer containing both an isopropylidene and arylether group was prepared by reducing the dinitro compound obtained from condensation of 4-nitrophthalic anhydride and 2,2-bis[4-(4-aminophenoxy)phenyl]propane. A series of novel poly(amide imide)s were prepared from DIDA and various diacids by direct polycondensation reaction using an equimolar amount of thionyl chloride in N-methyl-2-pyrrolidone (NMP) at room temperature. Inherent viscosities of these polymers were in the range of 22–70 mL g–1 (Mw = 28 500–120 500 by GPC, Mw/Mn = 1.55–1.80). Most of these polymers are soluble in aprotic polar solvents such as NMP and dimethylsulfoxide and even in less polar solvents, i.e. m-cresol and nitrobenzene. The films had tensile strengths in the range of 103–118 MPa. The glass transition temperatures were observed in the range of 190–285°C. The polymers were stable up to 395°C in nitrogen atmosphere, which revealed good thermal stability compared with a commercial poly(amide imide). Ein Diimid-Diamin-Monomeres (DIDA) mit sowohl einer Isopropyliden- als auch einer Arylether-Gruppe wurde durch Reduktion der entsprechenden Dinitroverbindung hergestellt, die durch Kondensation von 4-Nitrophthalsaureanhydrid und 2,2-Bis[4-(4-aminophenoxy)phenyl]propan erhalten worden war. Aus DIDA und verschiedenen Dicarbonsauren wurde durch direkte Polykondensation mit einer aquimolaren Menge Thionylchlorid in N-Methyl-2-pyrrolidon (NMP) bei Raumtemperatur eine Reihe neuer Polyamidimide erhalten. Die inharenten Viskositaten dieser Polymeren betragen 22–70 mL g–1 (Mw = 28 500–120 500, mittels GPC bestimmt, Mw/Mn = 1.55–1.80). Die Mehrzahl dieser Polymeren ist in aprotischen polaren Losungsmitteln wie NMP und Dimethylsulfoxid und sogar in weniger polaren Losungsmitteln wie m-Cresol und Nitrobenzol loslich. Die Zugfestigkeit von Filmen aus diesen Polymeren liegt im Bereich von 103–118 MPa. Die Glasubergangstemperaturen betragen 190–285°C. Die Polymeren sind unter Stickstoff bis 395°C thermisch stabil, im Vergleich zu einem handelsublichen Polyamidimid ein gur Wert.