KARAKTERISASI SIFAT BENDING KOMPOSIT LAMINAT HIBRID KENAF/(PP + HDPE) VARIASI PERBANDINGAN PP DAN HDPE
Abstract
Composite materials have been developed by automotive industries as a car interior panels. That is because the composite has the advantage of easily recyclable. There are two types of the hybrid composite, composite that uses two different fiber types in a single matrix, and also composite that uses two different types of the matrix in a single fiber. It has been a lot of research on composite using two types of different fibers, but information on the composite that uses two types of matrices are still relatively small. In this research, the researcher creates a composite using two kinds of the matrix and one fiber. The purpose of this research is to create a hybrid composite of kenaf fiber with PP and HDPE matrix to know the influence of the comparison matrix volume fraction of PP and HDPE towards composite bending characteristics.
Before being fabricated, kenaf fiber is first treated using NaOH with a concentration of 6% for 4 hours at room temperature. Then, cut the kenaf fibers to the length of ± 6 mm. The volume fraction of the fiber matrix PP : HDPE is 1:1, 1:2, and 2:1. The composite fabrication process is by composing the fiber and matrix on the molding with the type of laminate composite and then print using a hot press machine with a temperature of 165°C - 175°C. Afterwards, the composite is tested of the bending test refers to ASTM D 790 and the fracture section and cross section of the composite is analyzed using an optical microscope.
The bending test results show that the composite with a ratio of PP : HDPE 2:1 has the highest bending strength and bending modulus value that is 75.34 MPa and 2.03 GPa compared to the bending strength of ratio 1 : 1 and 1 : 2. That is because of the flexural strength of PP is higher than HDPE, also from the result of the optical test shows that kenaf fiber composite which has a PP: HDPE matrix with the ratio of 2: 1, the fiber is distributed equally in the matrix and no voids are visible.