This research aims to analyze the effect of a composite of HDPE plastic powder and acid
wood powder with a polyester resin matrix on hardness and microstructure tests with a mixture
composition of 10% - 20% HDPE plastic powder, 1% - 10% acid wood powder, and 50%
polyester resin. -85% composites are made via the hand lay-up method by pouring the material
into a mold. The standard size for hardness test specimens uses ASTM D785. The composite
hardness test results obtained the highest value for the composition ratio of 85% resin: 14
HDPE plastic powder: 1% acid wood powder, namely 513 HRB, and the lowest value for the
mixture ratio of 85% resin: 12% HDPE plastic powder: 3% % acid wood powder with a value
of 458.4 HRB. Based on the research results, the average value of hardness strength as HDPE
plastic powder increases and acid wood powder decreases, the higher the hardness value.
Observation of the micro and macro test structures shows that there are still a few air bubbles
in the specimen. By making composites from plastic and wood, excess plastic waste can be
reduced.
Keywords: Composite, HDPE plastic, polyster resin