Milkweed floss fiber/PLA composites: effect of alkaline and epoxy-silanol surface modifications on their mechanical properties. Issue 5 (3rd May 2020)

• Record Type: Journal Article
• Authors: Ovlaque, Pierre; Foruzanmehr, Mreza; Elkoun, Saïd; Robert, Mathieu
• Is Part Of: Composite interfaces. Volume 27:Issue 5(2020)
• Page Start: 495
• Page End: 513
• Publication Date: 2020-05-03
• Subjects: Milkweed floss -- PLA -- Bio-based composite -- Alkaline treatment -- Epoxysilane; Composite materials -- Periodicals; 620.11805
• DOI: 10.1080/09276440.2019.1655316
• Languages: English
• ISSNs: 0927-6440

Abstract

ABSTRACT: The aim of this study was to enhance the mechanical properties of milkweed floss (MW)/polylactic acid (PLA) composites by compatibilizing the interface between MW and PLA. MW floss is a natural fiber exhibiting a wide lumen and a thin cross-section. The addition of high specific surface area MW fibers to polymer matrices can lead to significant improvements of composites' mechanical performance. However, MW floss presents a poor bonding with PLA. This study evaluates the improvement of the adhesion and, consequently, of the composites' mechanical properties after MW modification with alkaline treatment or grafting of epoxy-silane. First, the influence of both treatments on the geometry, mechanical properties and roughness of MW fibers was investigated. Injection-molded composites made of 1wt.% treated MW were then characterized. Results showed that the mechanical properties of treated MW significantly decreased. Diminutions of 68 and 60% of Young's modulus (E) and ultimate tensile stress (UTS) were respectively measured for alkali treated MW (NaOH-MW). Reductions of 30 and 60% were respectively calculated for E and UTS of epoxy-silane treated MW (Si-MW). Still, improvements in the composites' mechanical properties were measured, such as increases of the UTS of 9 and 17% for PLA reinforced with NaOH-MW and Si-MW, respectively.