Study On Impregnating Enhancement-Fireresistance Treated Technology Of Cryptomeria Fortunei

Wood modification technology with Resin impregnation is one important approach enhancing the effective use of soft wood plantations.while wood fire-retardant technology is also an important subject in the areas of wood protection. In this thesis, The cedar wood (Cryptomeria Fortunei) was chose as the study object, using three different concentrations of watersoluble melamine-urea-formaldehyde resin(10%,20%,30%) and adding borax and boric acid flame retardant synthesize a wood modifier.After the impre-gnation process of vacuum pressure and the detection of physical and mechanical properties and the fireresistance analysis,the cedar wood was achieved enhancement and fire retardant.The results show that:(1) Boron combinations was added to resin,meanwhile the fire retardant didn't affect the property of resin.3% of borax and 1.5% of boric acid was permitted to mix with resin. The wood sample was vacuumed to 0.095 MPa in a treating tank for 20 minutes before impregnation with the resin solution, then treated wood sample 0.6 MPa air pressure for 120 minnutes,After discharging the remained solution,the tank was vacuumed to 0.095 for 10minutes.(2) The modifier comprehensively is enhancing mechanical strength of cedar wood,compared with untreated wood, the bend strength of modified wood increased by 48.6%, modulus of elasticity had an increase of 51.7%, and compressive strength parallel to grain by 153.0%.the hardness of wood in three different directions(transverse section, tangential section, radial section)also increased by 92.4%, 61.6%,140.7%.(3) The modifier effectively improved the dimensional stability of cedar wood,MEE reached 38.3%,ASE was 51.7%.(4) LOI of the modified wood is more than 50%, meeting the requirements of flame retardant in building construction.(5) The modified wood for RHR and THR have declined, the former 35%,and the latter 8%. and it have a good smoke suppression.the ignition time for the untreated wood is 12s, while the ignition time for modified wood is 73s, far from enhancing the wood nonflammable.In a word,the modifier of Enhancement and Fireresistance significantly improve mechanical strength and flame retardancy of the cedar wood.