Study On Technics Of Veneered Poplar Wood-based Panels

The paper takes the three different kinds of poplar wood-based panels, namely, poplar plywood, poplar medium density fiberboard and poplar particle board as base materials and four different kinds of veneers, namely, hard maple, red oak, white oak and walnut as surface decorative materials, and takes the glue penetration, peel strength, interfacial bonding strength and warp deformation as the research index, to study the optimized technics of different veneers veneered with poplar plywood and optimized technics of different base materials veneered with hard maple. At last, the warp deformation is studied. The result discovered that,(1) When poplar plywood as base material and hard maple as surface decorative material, additive, hot-pressing pressure and glue spreading amount have significant influence on glue penetration, hot-pressing temperature and hot-pressing time have little influence. When red oak as surface decorative material, glue spreading amount, hot-pressing temperature, hot-pressing pressure, additive and hot-pressing time have significant influence on glue penetration. When white oak as surface decorative material, the five factors all have little influence on glue penetration. When walnut as surface decorative material, hot-pressing temperature and hot-pressing pressure have significant influence on glue penetration, additive, glue spreading amount and hot-pressing time have little influence. Red oak has the most easily glue penetration among the four veneers.(2) When hard maple as surface decorative material and poplar plywood as base material, hot-pressing temperature, glue spreading amount, hot-pressing pressure and hot-pressing time have significant influence on peel strength; glue spreading amount has significant influence, hot-pressing pressure, temperature and time have little influence on Interfacial bonding strength. When poplar MDF as base material, hot-pressing temperature has significant influence, glue spreading amount, hot-pressing pressure and hot-pressing time have little influence on peel strength; hot-pressing pressure and glue spreading amount have significant influence, hot-pressing temperature and hot-pressing time have little influence on interfacial bonding strength. When poplar PB as base material, hot-pressing temperature and time have significant influence, glue spreading amount and hot-pressing pressure have little influence on peel strength; hot-pressing pressure and glue spreading amount have significant influence, hot-pressing temperature and time have little influence on interfacial bonding strength.(3) The most appropriate condition for poplar plywood are as follows: glue spreading amount-100g/m2, hot-pressing pressure-0.8Mpa, hot-pressing temperature-100℃, hot-pressing time-240s; the most appropriate condition for poplar MDF are as follows: glue spreading amount-100g/m2, hot-pressing pressure-1.1Mpa, hot-pressing temperature-110℃, hot-pressing time-180s; the most appropriate condition for poplar PB are as follows: glue spreading amount-100g/m2, hot-pressing pressure-0.5Mpa, hot-pressing temperature-110℃, hot-pressing time-300s.(4) The correlation formula between flour additive amount and peel strength is y = -0.0116x3 + 0.3834x2 - 4.2525x + 17.764, and correlation coefficient R2=0.9909, when the flour additive amount is 8%, the peel strength is the best; the correlation formula between deposited time and interfacial bonding strength is y = -0.00003x3 + 0.0019x2– 0.0311x + 1.3086, and correlation coefficient R2=0.9744, when deposited time is 40min, the interfacial bonding strength is the largest.(5) The warp deformation of veneered poplar MDF and veneered poplar PB is comparative. The factors have little influence on warp deformation degree of diagonal direction and length direction, and hot-pressing time has significant influence on warp deformation degree of width direction and when hot-pressing time is 180s, the warp deformation degree of width direction is the least.