Preparation And Application Of Aldehyde-free Flame-retardant Adhesive For Particleboard

With the intensification of the shortage of wood resources around the world,the use of its processing residues and logging residues as raw materials to produce particleboard has become the main way for countries to resolve the contradiction between wood supply and demand.At the same time,the application of wood particleboard has gradually shifted from the furniture industry to the fields of construction and ships.In this thesis,soybeans with low price and readily available life are used as raw materials to prepare soybean protein powder suitable for the wood industry,and then modified liquids and flame-retardants are added to obtain soybeanbased aldehyde-free flame-retardant adhesives.The flame retardant adhesive is applied to the processing of particleboard and a green environmentally friendly particleboard with satisfactory physical and mechanical properties and excellent flame retardancy is obtained.The main researches in this thesis are as follows:Preparation of formaldehyde-free adhesive for particleboard: Using soybean as raw material,soy protein powder for wood industry is prepared,and then modified liquid is added to obtain formaldehyde-free adhesive.By preparing particleboard samples and testing its mechanical properties,the soybean protein in the formaldehyde-free adhesive for particleboard is determined.The suitable ratio of flour and modified liquid is soy protein powder: modified liquid: distilled water = 1:1:1.Preparation of aldehyde-free flame-retardant adhesive for particleboard: Six single flame retardants and one composite flame retardant were screened out and added as flame retardant components to the above-mentioned formaldehyde-free adhesive to obtain formaldehyde-free flame-retardant adhesive.Testing of flammability,exploring suitable flame retardant and its added amount.The results show that the laboratory-made composite flame retardant KZDF0 has the best flame retardant effect,and the physical and mechanical properties of particleboard are improved when the added amount is 10%(compared with the mass of the dry particleboard).Study on the process of formaldehyde-free flame-retardant particleboard: Based on the above,through the single-factor test method,the influence of hot-pressing process factors on the properties of particleboard was explored.The results show that the suitable hot-pressing process conditions for making particleboard(6 mm)with the above-mentioned aldehyde-free flame-retardant adhesive are hot-pressing time of 9 min,hot-pressing temperature of 150℃,and hot-pressing pressure of 3.5 MPa.The particleboard samples submitted for inspection have been tested by authoritative institutions: the density deviation,moisture content,static flexural strength,elastic modulus,internal bonding strength,and surface bonding strength of the board have reached the requirements of using household particleboard(P2)in a dry state in the GB/T4897-2015 standard.The formaldehyde emission is 2mg/kg(perforation method),which is equivalent to the wood body value.The oxygen index is 27.3%,which is close to the requirements of B1 flame-resistant building materials.