Systematic study of the relation between NIR spectrum and particle size of polymer for application in the monitoring of emulsion polymerization processes

• Grant number: 15/23543-5
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: March 01, 2016
• End date: September 30, 2016
• Field of knowledge: Engineering - Chemical Engineering - Chemical Process Industries
• Principal Investigator: Reinaldo Giudici
• Grantee: Cristhiane Assenhaimer Takahashi
• Host Institution: Escola Politécnica (EP). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Emulsion polymerization is a largely and increasingly used technique in industrial production of paints, resins, among others, due to its versatility and capacity of producing products with different properties. For improving emulsion polymerization processes, it is necessary the development of techniques for in-line monitoring, including the monitoring of particle size of the polymer produced during the reaction. NIR spectroscopy, combined with fiber optic sensors, has shown potential for this application; however, the data obtained by this technique is not a direct measurement of the desired variables: it is necessary to develop a calibration model to correlate spectra data with the desired properties to be monitored. The fitting of a good calibration model is crucial for the success of this method and, although robust models are generally fitted, a model that could be applied for different formulations and process conditions has not been found yet. The spectrum region between 10.475 and 13.000 cm-1, have high sensibility to particle size evolution during emulsion polymerization, but it has little absorbance interference from the chemicals of the reaction, indicating the potential of this spectrum region to be used for predicting particle size evolution in emulsion polymerization. Therefore, the objective of this research project is the careful and detailed study of the influence of polymeric particle size in NIR spectrum, in order to enable the future development of a single and robust calibration model, suitable for monitoring particle size of emulsion polymerization processes, in different process conditions and different formulations. (AU)