Preparation and structural characterization of sodium polyphosphate coacervate as a precursor for optical materials

• Autor(a) principal: Franco, D. F. [UNESP]
• Data de Publicação: 2016
• Outros Autores: Barud, H. S., Santagneli, S. [UNESP], Lamarca, R. S., Santos, Bruno F. [UNESP], Silva, M. A.P., de Oliveira, L. F.C., Ribeiro, S. J.L. [UNESP], Nalin, M. [UNESP]
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1016/j.matchemphys.2016.05.049; http://hdl.handle.net/11449/176922
• topic: Coacervates; Glasses; Nuclear magnetic resonance (NMR); Optical properties

This paper describes the preparation of Sodium Polyphosphates Coacervates (NaPC) through the direct addition of different methanol molar fractions to a sodium polyphosphate solution. The presence of methanol reduces the dielectric constant medium and it promotes the coacervate formation. Rheology measurement shows that the NaPC viscosity is dependent on a methanol molar fraction, which is caused by the dielectric constant reduction of the water-methanol mixture. Raman spectra for the lyophilized NaPC show that the symmetric P-Ot stretching mode is more sensitive than the symmetric P-Ob stretching mode, due to the approach of the adjacent polyphosphate chains. The 31P NMR spectra also confirm a decrease in the Q2/Q1 ratio because of the methanol content. Besides, we have obtained transparent soft Glass-Materials to melt NaPC at 800 °C.