Research On Manufactory Of Howllow Rice-Straw Particle Board Made By Extrusion Machine

The Project come from the problem of Wood Saving Development Center, and The author was sponsored by National Science Foundation of China for 863 Program: Manufactory Technology of Wood, Bamboo and Agricultural-residues Composites when she studed for her master degree. In the paper the author mainly researched on the molding characteristics of rice-straw particle board made by extrusion machine, the technics on the board and the use characteristics of the production such as heat insulation, hinder burn and resist impact.There are lots of difference between extrusion molding and flat-press molding, And that produce howllow rice-straw particle board was feasible proved by the theory and the practice. And it has been applied for the Nation Patent. It break through the difficult problem of that it can't produce rice-straw particle board with Urea Formaldehyde resin at first time. It confirm the following hot-press technics. The hot-press temperature is 160degrees centigrade, The board per meter cost two point seven minute to come out from machine, The moisture of the raw material is frome three percent to four percent. The resin accession quantity is four point five percent, The ratio of qulity of rice-straw and wood is seven to three.The modulus of rapture of the board can arrive the request of the GB4897-85. At the same time the modulus of rapture of the board was machined secondly in the factory is 7.09MPa, and the out intensity of the board is 0.75 MPa, And both of them can arrive the request of the GB4897.2-2003. The dissociation formaldehyde quantity of the board is three milligram per one hundred gram of board measured by Nanjing Wood-based Panels Testing Center of the forestry Administration of China. It show that the rice-straw can reduce the dissociation formaldehyde quantity in the boardThe heat conduction value of the howllow rice-straw particle board is 1.5W/K·m, and it is equal to the heat conduction value of the howllow wood particle board. And the smoke density grade of the straw board is 6.81 and it is higher than the wood board. It take resist impact test to the wooden door with the core is rice-straw hollow particle board, and the result show that the door can't arrive the request of the GB17565-1998 which is used to weigh the door against sheft. So the door with the core is rice-straw hollow particle without metal cover can't be used as outside doors.