Abstract :
Natural fibers have hydrophilic (water-loving) properties and are difficult
to combine with hydrophobic (water-repellent) matrices. The heavily soiled fiber
surface affects the bond with the matrix. The fiber surface treatment can be
carried out by chemical, physical or microbiological processes. A widely used
method of removing contaminants from the fiber surface is the chemical treatment
process. Chemicalcompounds that are widely used are sodium hydroxide (NaOH)
The main components of this research are hemp fibers and polyester resin
composites, which are manufactured using the hand lamination process. The
composite consisted of random flax fibers, 15% by volume composite fibers, and
dissolved NaOH at a concentration of 2.5%, 5%, 7%, 10% for 2 hours of
immersion. Tensile test (ASTM D 638) and SEM (scanning electron microscope).
The result of the highest tensile strength value is the composition with a
5% solution of 78.96 MPa. the lowest strength is found in a 10% solution of 37.66
MPa. The results of the SEM test of the test sample with the highest tensile
strength at 5% composition show that if the fiber and matrix bond well, the SEM
results show that the best solution is 5%, because the more concentrated the fiber,
the more the solution/ becomes more brittle.