Fractional precipitation of sodium polyphosphate and characterization by 31P NMR: an experiment for pysical chemistry classes

Química Nova

Universidade Federal de Goiás, Goiânia, Brasil¹  Universidade Federal do Piauí, Teresina, Brasil¹  Damasceno, Fernando Cruvinel¹  Galembeck, Fernando¹  Alcantara, Glaucia Braz¹  Moita Neto, José Machado¹  Universidade Estadual de Campinas, Campinas, Brasil¹  Lima, Emília Celma de Oliveira¹ 

关键词: sodium polyphosphate;    fractional precipitation;    31P NMR.;   

DOI  :  10.1590/S0100-40422010000900031

学科分类：化学（综合）

来源: Sociedade Brasileira de Quimica

【 摘 要 】

This text describes an experiment on fractional precipitation of a polymer together with determination of average degree of polymerization by NMR. Commercial sodium polyphosphate was fractionated by precipitation from aqueous solution by adding increasing amounts of acetone. The polydisperse salt and nine fractions obtained from it were analyzed by 31P Nuclear Magnetic Resonance and the degree of polymerization of the salts and of the fractions were calculated. Long-chain sodium polyphosphate was also synthesized and analyzed. This experiment was tested in a PChem lab course but it can be used also to illustrate topics of inorganic polymers and analytical chemistry.

【 授权许可】

Unknown