Studies On Design, Synthesis And Properties Of Some High Performance Aromatic Polyamides Materials

From the molecular design, four aromatic novel diamines I -IV and s four aromatic novel diacids 1-4 containing phthalazinone moieties are synthesized starting from bisphenol-like phthalazinone via two step reaction. The chemical 3D model reveals that the diamines I -IV / diacids 1-4 are twist nonplanar structure. The high molecular weight of poly (phthalazinone amide)s are acquired from the novel diamines I -IV and diacids 1-4 respectively with different aromatic diacids / commercial diamines through direct polycondensation using Yamazaki method. These polymers exhibit high glass transition temperature (Tg =298.6-356.0 C) and good thermooxidative properties with the 10% weight loss temperature are all above 400C. The aromatic polyamide films had tensile strength of 60-101MPa, elongation to break of 5.8-13% and tensile modulus of 0.8-1.4GPa. The order of the coefficient of electrical resistant is 1015-1016. The polymers are readily soluble in polar solvents such as NMP, DMF and m-cresol etc. The result showed that the polyamides have the combination of excellent thermal property, solubility, mechanical property and electrical resistance properties. The structure of diamines I -IV, diacids 1-4 and their polymers is confirmed by MS^ FT IR and 'H NMR.A series of new aromatic poly(amide imide)s PI-P IV containing phthalazinone moieties are synthesized from the novel diamines I - IV by direct Yamazaki polycondensation. The synthesized poly(amide imide)s in high yield have high molecular weight with the inherent viscosity in the range of 0.49-0.80 dLg-1. They exhibit excellent thermal property (Tg= 317-355 C), good thermooxidative, excellent mechanical and electric resistant properties. They are readily soluble in polar solvents such as NIv^ DMF and m-cresol etc and their structure is confirmed by FT IR and 'H NMR. All poly(amide imide)s are amorphous.A class of novel aromatic copolyamides bearing phthalazinone moieties on the backbone P I a-d - P IVa-d have been prepared from the novel diamines I -IV, commercial diamines and different commercial diacids. The solubility of copolyamides is improved greatly because of the introduction of phthalazinone to the parent chain. Thus the investigation deals with the influence of species of novel amines, the molar ratio of diamines to commercial diamines etc on the performance of copolymers. Other more the copolymers show excellent thermal and good mechanical properties.The gas transportation property based on the membrane materials of novel poly (phthalazinone amide)s is reported. The result indicates that the gas permeability coefficientis on the same level with polysulfone but the selective coefficient is rather above it. The ultrafiltration membrane is prepared and the effects of solvents, polymer concentration, additive, and temperature of gel bath on the membrane performance are studied. While DMAc is used as solvent and EGME or diethyl ether is used as additive, the rejection against PEG 12000 is up to 100% under 0.1 Mpa.