Study On Syntheses,Structures And Nucleation Efficiency Of Lanthanide Coordination Polymers With Aromatic Carboxylic Acid

Lanthanide coordination polymers have attracted widespread attention for their fantastic properties,various structures,and extraordinary photo-magnetoelectric effect,etc.Moreover,they have potential application value in many fields,such as magnetic materials,luminescent materials,selective catalysis,gas storage and absorption,separation,sensors,host-guest chemistry,and biomedicine,etc.In this dissertation research,three novel rare earth coordination polymers,the mononuclear 1D complex 1,{[Nd(Npg)(pha)(H2O)]·2H2O}n,the binuclear 3D network frame structural complex 2 with microporous,[Nd2(pha)2(ada)(H2O)4]n,and the trinuclear 3D supermolecular structural complex 3,[Nd3(pha)4(phen)2(NO3)]n,(Npg = N-Phthaloylglycine,pha = Benzene-1,2-dicarboxylic acid,phen = 1,10-Phenanthroline monohydrate,ada = Adipic acid),have been in situ hydrothermally(solvothermally)synthesized by the materials of neodymium nitrate hexahydrate,aromatic carboxylic acids,and other ligands.These complexes are characterized by elemental analysis,infrared spectrum,X-ray single-crystal diffraction(SXRD),thermogravimetric analysis(TGA)and powder XRD(PXRD).Their crystal structures are refined by Shelx-97 and Olex2-1.2.Different concentration of the lanthanide coordination polymer 1 was incorporated into isotactic polypropylene(iPP).Then,the nucleation effect of the complex 1 on iPP was evaluated by mechanical properties tests,measuring the heat deflection temperature,non-isothermal crystallization behaviors tests on DSC,crystalline morphologies on a polarized optical microscope,and wide angle X-ray diffraction analysis,etc.The results indicate that the complex 1 has a satisfactory nucleation effect in isotactic polypropylene(iPP).It is an effective stiffening nucleating agent.Meanwhile,it has certain toughening function.When the content of the complex 1 is 0.15wt%,compared to those properties of neat iPP,the flexural modulus,bending strength and tensile strength of modified iPP are increased by 31.5%,21.8% and 13.6%,respectively.These changes are the common features of stiffening nucleating agents.However,instead of being declined,the Izod impact strength of nucleated iPP is increased by 28.8%.This situation has rarely been observed before,when the addition is a stiffening nucleating agent.It can improve both the toughness and the rigidity of nucleated iPP well.It bears realistic significance that how to keep the polypropylene with a good balance of toughness and stiffness.