Extruded PVDF composites with anatase and gamma-alumina: a study on properties and stability

• Published in: Polymer-plastics technology and engineering Vol. 60; no. 9; pp. 949 - 961
• Main Authors: Arias, Jose Jonathan Rubio, Jorge, Fábio Elias, Gondim, Fernanda Fabbri, Cândido, Ludmila Da Silva, Értola, Raphael, Rocha, Ana Beatriz, Fernandes, Beatriz, Pedroso Silva Santos, Bianca, Chaves, Erica Gervasoni, Peres, Augusto Cesar De Carvalho, Marques, Maria De Fátima Vieira
• Format: Journal Article
• Language: English
• Published: New York Taylor & Francis 13.06.2021; Taylor & Francis Ltd
• Subjects: Alumina; Aluminum oxide; Anatase; Composite materials; Extrusion; Mechanical properties; nanoparticles; Oxidation; Phase transitions; Polymers; PVDF; Thermal transformations; Thermodynamic properties; titania; Transitional aluminas
• ISSN: 2574-0881; 0360-2559; 2574-089X; 1525-6111
• DOI: 10.1080/25740881.2020.1867175

The importance of alumina and titania is exceptionally high for modern life since they appear in all materials science fields and perform essential tasks without which modern life would not be possible. Every day, the window of application of these oxides expands, including polymer science and technology. Alumina and titania as nanofillers are explored in the present work, aiming to expand the window of application of these oxides as a secondary phase in extruded PVDF composites. Unexpected findings lead to the belief that PVDF induces an unknown phase transition/oxidation in γ-alumina and anatase, which causes their composites to be dark and present unusual thermal behavior; T max decreased 75 and 61°C upon the incorporation of anatase and γ-alumina to PVDF matrix, respectively. All the titania and alumina composites possess lower mechanical properties and degradation temperatures than pure PVDF; however, the crystallinity degree is 3% higher for rutile, which could have positive application in membranes and pipes with selective permeability. The formation of the transformation mentioned above in γ-alumina and anatase decreased the viscosity of the polymer by 6 and 24% respectively, which is closely related to the unexpected thermal behavior of those composites and possess a new research subject about the causes of this transformation induced by polymer and its possibility for future applications.