Mechanical, thermal, and water absorption properties of melamine–formaldehyde-treated sisal fiber containing poly(lactic acid) composites

Jiratti Tengsuthiwat, Udom Asawapirom, Suchart Siengchin, J. Karger-Kocsis

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6 Citations (Scopus)


The present study focuses on the melamine–formaldehyde (MF) coating ratio and silanization of PLA/sisal composites. Poly(lactic acid) (PLA) was melt blended with short sisal fiber with and without MF resin coating. MF was applied at different weight ratios (sisal:MF = 1:1; 1:3, and 1:5) to coat the untreated or silanized sisal fibers which were incorporated up to 20 parts per hundred resin (phr) amount in PLA. PLA/sisal composites were produced by compression molding. It was found that the sisal:MF coating ratio at 1:1 by weight improved the tensile strength and tensile modulus of the composite with 10 phr sisal by 4% and 57%, respectively, compared to the virgin PLA. The initial and final decomposition (Ti) and (Tf) of PLA with untreated sisal were changed from 330.8 and 367.1 to 336.2 and 370.4 °C, respectively, after MF-coating (sisal:MF weight ratio = 1:1). This enhancement in thermal stability was attributed to the strong interaction between the MF and sisal fiber. The water absorption of PLA/MF–sisal composites slightly decreased with increasing sisal:MF ratio. This is due to the fact that the MF-coating substantially reduced the hydrophilic properties of sisal. Moreover, FTIR spectra and SEM images proved that sisal fibers were coated by MF resin successfully.

Original languageEnglish
Article number45681
JournalJournal of Applied Polymer Science
Issue number2
Publication statusPublished - Jan 10 2018



  • biopolymers and renewable polymers
  • cellulose and other wood products
  • mechanical properties
  • thermogravimetric analysis (TGA)

ASJC Scopus subject areas

  • Chemistry(all)
  • Surfaces, Coatings and Films
  • Polymers and Plastics
  • Materials Chemistry

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