Material properties of acetylated jute-mat composites

Abstract

Jute-mat (JM) reinforced polyvinylchloride (PVC) composites were prepared with acetylated and non-acetylated JM by heat-pressed method at 160ºC with various contents of JM and PVC. Owing to the incompatibility between hydrophilic JM and hydrophobic PVC, their composites become incompatible having poor adhesion between them. Due to this poor interfacial adhesion, the PVC-JM composites show inferior properties. That is why fiber surface of JM is modified by chemical treatment, and acetylation of JM is one of the treatments followed in this study using acetic acid (CH3COOH). When the JM fiber surface is treated with acetic acid, the chemical reaction between JM and CH3COOH results in acetylated JM having chemical structure of JM-O-C=O-CH3. This acetylated fiber represents hydrophobic character and exhibits better adhesion with hydrophobic PVC when combined. Structural, mechanical and thermal properties of a neat PVC sample and a series of untreated and treated PVC-JM composites were characterized by a Fourier transform infrared (FTIR) spectrometer, a universal testing machine and a coupled differential thermal analyzer (DTA)/thermogravimetric analyzer (TGA). Water intake measurements of these samples were also performed. FTIR spectra show distinct absorption peaks for neat PVC and untreated and treated PVC-JM composites, suggesting the adhesion between JM and PVC. While the neat PVC does not show any water absorption, the untreated PVC-JM composites exhibit higher water intake than the treated composites. This is due to the fact that after acetylation the hydrophilic moiety of JM is filled up by the acetyl group. Mechanical properties such as Young’s modulus (YM) and tangent modulus (TM) of the acetylated PVC-JM composites are observed to be higher than those of the non-acetylated PVC-JM composites and the neat PVC, suggesting better performance due to chemical treatment. Surface micrographs reveal a better adhesion between acetylated JM and PVC than between untreated JM and PVC. The decomposing temperature (Td) of the treated composites is observed to be higher than that of the neat PVC and untreated composite. Thus, the acetylation of JM produces the high performance biodegradable composites.