Síntese e caracterização do poli (fluoreto de vinilideno) dopado com complexo de cério e complexo de neodímio

Abstract

The polyvinylidene fluoride (PVDF ) is a semicrystalline polymer presenting polymorphism , being the α phase more easily obtained by crystallisation from solution. But depending of processing conditions is possible crystallization of the β phase, which has several applications, the most relevant are piezoelectric and pyroelectric properties, due their properties. The preparation of PVDF films doped with rare-earth ions compound alter the properties of the polymer matrix , obtaining a material with interesting optical and mechanical properties. Although the process of crystallization solution of PVDF film is much reported, there is still a need for further studies to better understand the effects caused by addition of dopant on the structural and optical properties. Thus, this essay describes a study on the synthesis and characterization of polymeric films of poly ( vinylidene fluoride ) doped with cerium and neodymium, using these metal compound with the ligand 3,4- methylenedioxycinnamato (C10H8O4), aiming to unite the same properties with the properties of PVDF and also check the influence of the ligand coordinated to the metal. The form of the composite films were prepared in the following concentrations 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0 % ( w / w) and characterized by FT- IR and X-ray , which was estimated relative percentage of the β phase and the identification of the incorporation of dopants in the polymer matrix. The composite was analyze by thermogravimetry (TG), which showed the stability of the samples with the addition of dopants. As for the characterization of the optical properties was made measured molecular absorption in the UV -Vis and fluorescence spectroscopy, checking for the emission increase with the addition of dopant and determination of electron transitions energies of hypersensitivity. The results showed an extend of the emission spectrum of the PVDF wavelength region of from orange, due to the addition of neodymium in the matrix, that for samples doped with neodymium compound. On the other hand, there was a transition from β phase to α phase, indicating improved optical and mechanical properties. Thus the experimental results showed that the PVDF matrix doped with neodymium ions coordinated the ligand 3,4- trans methylenedioxycinnamato is a potential candidate for optical applications, such as white light emitter.