Novel High Performance Resin Containing Phthalazinone

Aromatic, heterocyclic polyimides exhibit excellent properties, outstandingmechanical properties and oxidative stability and are of major commercial andindustrial importance. Polyimides are widely used in place of metals and glass inhigh-perfOrmance aPplications throughout the electronics, automotive, aerospace,and packaging industries. However, their aPPlication have been limited in manyfields because aromatic polyimides are normally insoluble in common organicsolvents and do not melt below their decomposition temperatWe. The rigidstructures have high glass tfansition temperatures or crystalline melting points andvery poor solubility which drawbacks to their use. Thermoplastic, injection-moldable polyetherimides of the type represented by UItem dissoIved it. Theintroduction of aromatic ether grouPs into polyimides, howeveT, lowers glasstransition temperatuxe. Thus in the synthesis of any thermal stable polymer, acompromise has to be reached betWeen thermo-mechedcal Properties andprocessibility TherefOre it is very important and challenging to stUdy vedousstructure-property relationships in order to predict the effects of smictUralmodifications on po1ymer properties.Recently introducing a heteroaromatic and noncoPlanar moiety into thepolymer backbone has been demonstrated to be a tinique aPproach to organ-soluble rigid rod or rod-like polyinddes. Since, to our best knowledge, no reportson the synthesis of dianhydride monomer and polymer containing thephthalazinone moiety have aPpeared in the literatUre to date. lt is appropriate tosynthesize dianhydride monomers and a series of polymers based on thesemonomers. The highiight of the dissertation is as fol1ows.Four novel noncoplanar and asymmetric dianhydride: 2-(3,4-dicarboxyl-N-phenyl)-4-(3',4'-dicarboxyl-phe l -onedianhydride (4), 2-(3,4-dicarboxyl-N-phenyl)-4-dimethyl)-phenyl)-2,3-phthalaZi dianhydride (5), 2-(3,4-dicarboxyl-N-phenyl)-4-(3 ',4'-dicarboxyI-phenoxyl-4-(3-p l -onedianhydride (6), 2-(3,4~dicarboxylWThenyl)-4-(3'methy l ) -Pheny l)- 2, 3 -phthalaZine - l - one dianhydri de (7 ) were synthe s ized o ncondensation of asymmetric heterocyclic bisphenol-like compounds with N-p he ny l -4 -c hloro - phthal imi d e in presence of potassi um carbo nate re sp e c t ively,giving corresponding diAnides, followed by hydrolyzed and dehydrated as usual.Unlike commonly used dianhydrides, compound 4-7 are quite stable on exposureto air. Their StrUcture was unambiguously confirmed by FT-IR, lH- and "C-NMR,2D-NMR spectroscopies and high-resolution mass spectrometry.The" one-step" solUtion polymerization of the dianhydride 4-7 obtainedwith various aromatic diaxnines a-e were undertaken successfully in m-cresol inthe presence of a catalytic amount of isoquinoline at 200C. High molecularweight poly(ether imide)s were readily formed in above 20h, except fOr polyimidefrom compound 4 and p-phenyl diamine which precipitated out duringpolymerization. Spectroscopic data confirmed structure of polyetherimides.Polytherimides having intrinsic viscosities of 0.45-1.8l dL/g in N-methyl-2-pyrrolidine or m-cresol were obtained. These polyetherimides are readily solublein many common organic solvents such as N, N-dimethylacetamide, N-methyl-2-pyrrolidine, m-cresol and chloroform. Tgs were in range of 279-355C, asdetermined by differential scanning calorimetry. Tgs of polyetherimides derivedfrom compound 4,5,6,7 and m-phenylenediamine were 90t higher than the Tg(2l7t) of the commercially available polymer derived from BPA-dianhydrideand m-phenylenediamine. Degradation temperatues fOr 5% weight loss occurredall above 430 t in nitrogen. Young's moduli of thin film, fOr somepolyetherimides ranged from to Gpa as assessed by mechanical analysis.Copolyetherimides from two dianhydrides containing phthalazinone anddiamines were obtained by resolution polycondensation. Depending on thediarnine used, various copolymers with various pro...