Particleboard is a composite material consisting of two or more constituents, namely an adhesive (matrix) and a filler which can be in the form of fibers or particles. This study used coffee grounds as filler particles and epoxy resin as a matrix. The purpose of this study was to determine the effect of ball milling time on thermal, mechanical and physical properties of coffee grounds particle board with epoxy resin adhesive (matrix). This research was conducted by varying the ball milling time (0 hours, 10 hours, 20 hours, 30 hours, and 40 hours) with the size of the coffee grounds particle sieve before ball milling was 140 mesh and the composition of coffee grounds: epoxy resin was (80% volume: 20% volume). The tests carried out include thermal properties, namely thermal conductivity, mechanical properties, namely MOE and MOR, and physical properties, namely density and porosity. Particle board is made by pressing techniques at a pressure of 9 tons for 30 minutes in 15 cm x 15 cm x 1 cm concrete. The testing of thermal properties is based on British standard (British standard), mechanical properties and physical properties are carried out based on ASTM standards. The results showed that the variation of the ball milling time of coffee grounds: epoxy resin that affects the thermal properties, mechanical properties and physical properties of the particle board. The value of the thermal properties test is that the thermal conductivity test ranges from 0,1004-0,1276 W/moC, the value of the mechanical properties for the modulus of elasticity (MOE) ranges from 176,76-503,92 kgf/mm2, the value of the fracture modulus (MOR) ranges from 2,654-5,35 kgf/mm2. The mechanical properties of particleboard have met the standards of the American National Standards Institute (ANSI) for MDF type particleboard which is classified into Medium Density (MD) and High Density (HD) classes. The value of the physical properties test, namely the density test, ranged from 1,329-1,468 gram/cm3, porosity ranging from 6,284-16,769%. Based on the thermal conductivity value obtained, the coffee grounds particle board with epoxy resin adhesive has a low thermal conductivity value so that it can be applied as a thermal insulation material.
Keywords: particle board, coffee grounds, epoxy resin, thermal, mechanical, physical properties.