Abstract :
Natural Composite (NACO) is a material that could be developed in
Indonesia. Mechanically bonded composites reinforced by natural fibers can be
improved by chemical treatments such as the alkaline treatment. It is often used as
it is more economical. The purpose of this study was to study the effect of alkaline
immersion on the bending properties of hemp fiber reinforced composites.
The main ingredient of the research is hemp fiber and transparent polyester
resin 108. The hardener used is a MEKPO hardener. The composite was made by
hand-lay-up method with a long immersion time of 2 hours. Composites consist of
random hemp fiber, a 15% volume fraction of composite fibers with variations in
alkali immersion (NaOH) 1.5%, 2%, 2.5%, 3% and 3.5%. The flexural test
specimen refers to ASTM D 790-03. The fracture section is examined to identify the
fracture mechanism.
The highest bending test result was obtained with an alkaline concentration
of 1.5% at 81.902 MPa. Based on the observation of the macro structure, there were
a type of fiber pull out and fiber break on the composite.