Research on Mechanical Properties of Bamboo Modified with Melamine-Formaldehyde Resin

Shortage of wood and demand for high quality bamboo products necessitate study on pretreatment to improve properties of bamboo. The effects of Melamine-Formaldehyde (MF) resin on mechanical properties of bamboo were researched through orthogonal experiment. The influences of concentration, time and temperature in infiltrating process on compressive strength of bamboo are discussed. The results of experiment and analysis reveal that the concentration of MF resin and infiltrating time significantly influence on the compressive strength of bamboo, but the effect of the temperature on compressive strength is not significant. With increment of concentration, time and temperature, the infiltration is in a growing trend. Low concentration of MF resin solution results in less resistance to infiltration, the best concentration of infiltrator is not more than 10%. For longer infiltrating time, more MF resin may infiltrate into bamboo but more substances leach out from bamboo. The compressive strength of bamboo reached the maximum when the bamboo is infiltrated for two hours. The appropriate infiltrating temperature is at 80°C, in this case, MF resin solution is not too viscous, thus more resin may infiltrate into bamboo while less substances leach out from bamboo. For best mechanical properties of MF resin modified bamboo, the optimal treatment process is to infiltrate the bamboo in not more than 10% MF resin solution for 2h at 80°C. Then the density and strength of bamboo are improved, the highest compressive strength reached 139.8 MPa.