Untitled in english

Author(s)

Guillermo Palmer Martín

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Escola Politécnica (EP/BC)
• Defense date: 2001-07-31

Examining board members

Nicole Raymonde Demarquette; Reinaldo Giudici; Miriam Rocchi Tavares

• Advisor: Nicole Raymonde Demarquette

Abstract

Interfacial tension between molten polymers is one of the most important parameters that control the compatibilization between components of a polymer blend. However, because of experimental difficulties encountered in its determination, few data are available regarding interfacial tension between molten polymers. In this work the theories of Tomotika [1936] and Tjahjadi et al., [1994] relative to the method of breaking thread and the theories of Tjahjadi et al., [1994] and Cohen and Carriere [1989], relative to the method of imbedded fiber retraction, are developed to determine the interfacial tension between molten polymers. The experimental procedures of these two methods were developed and the limits, advantages and disadvantages of each method were evaluated. Data of interfacial tension between polypropylene and polystyrene, as well as between polypropylene and polycarbonate are reported and compared with data of the literature and with the data of interfacial tension calculated according to empirical equations. The experimental procedures developed for the methods of breaking thread and imbedded fiber retraction are tested for the determination of the interfacial tension between polyethylene of low density modified with maleic anhydride and poly (vinyl alcohol-co-ethylene). The experimental results for this polymer pair are shown. (AU)