Study On Synthesis Of Novel Aromatic Polyamides By Heterogeneous Palladium-catalyzed Carbonylative Polycondensation

In this dissertation,we have investigated heterogeneous palladium-catalyzed carbonylation polycondensation by using magnetic nanoparticles-supported bidentate phosphine palladium complexes as catalysts to synthesize various new aromatic polyamides.The research work is mainly divided into three parts as follows:1.A new aromatic diiodide compound?BIPPO?with triphenylphosphine oxide structure was designed and synthesized.A series of new aromatic polyamides with triphenylphosphine oxide structure were synthesized by the carbonylative polycon-densation of BIPPO,various aromatic diamines and carbon monoxide catalyzed by a heterogeneous palladium complex[Fe₃O₄@SiO₂-2P-PdCl₂].The inherent viscosities of the polymers obtained were up to 0.76 dL/g.These polymers had excellent solubility and were easily soluble in polar aprotic solvents,and also soluble or swollen in THF at room temperature.The polymers had good thermal properties and their glass transition temperatures?Tgs?were in the range of 196-249oC,and the temperatures at 5%weight loss were in the range of 441-490oC in nitrogen.The films casting from DMAc solutions of these polymers were transparent and tough,and had tensile strengths of 78.5-91.6 MPa.In addition,this heterogeneous palladium catalyst could be recycled at least 8 times with almost consistent activity.2.A series of novel aromatic polyamides bearing both triphenylphosphine oxide and cardo structures were synthesized by heterogeneous palladium-catalyzed carbony-lative polycondensation of BIPPO,various aromatic diamines with cardo structures and carbon monoxide with Fe₃O₄@SiO₂-2P-PdCl₂ as catalyst.The inherent viscosity of the polymers prepared was up to 0.76 dL/g.These polymers were easily soluble in polar aprotic solvents,and swollen in THF at rooom temperature.Thermal stability of the polymers were found to be outstanding,their glass transition temperatures?Tgs?were in the range of 240-259oC,and the temperatures at 5%weight loss were in the range of 463-501oC in nitrogen.The films casting from DMAc solutions of these polymers were transparent and tough,and had tensile strengths of 78.6-83.4 MPa.The optical transmittance of the polymer films were about 90%at the wavelength of 600nm.3.A series of new poly?arylene ether sulfone amide?s with cardo structures were synthesized by heterogeneous palladium-catalyzed carbonylative polycondensation of aromatic diiodides having ether sulfone linkages,aromatic diamines bearing cardo structures and carbon monoxide in the presence of the Fe₃O₄@SiO₂-2P-PdCl₂complex.The inherent viscosities of the polymers were up to 0.77 dL/g.These polymers had excellent solubility,and were easily soluble not only in polar aprotic solvents,but also in common solvents such as pyridine and THF at room temperature.These polyamides had outstanding thermal properties,and their glass transition temperatures?Tgs?were in the range of 244-287oC,and the temperatures at 5%weight loss were in the range of 438-475oC in nitrogen.The polymer films obtained by casting from the corresponding DMAc solutions of the polymers were transparent and tough,and had tensile strengths of 78.8-84.4 MPa.The optical transmittances of the polymer films were higher than 90%at the wavelength of 600 nm.