Study On Properties Of Heat Treated Mongolian Scotch Pine (Pinus Sylvestris Linn .var.mongolica Litv) Wood

In this paper, the character of heat treated Mongolian Scotch pine wood(Pinus sylvestris Linn .var.mongolica Litv) 200 and heat treated Mongolian Scotch pine wood 215 had been comparatively studied with the ammoniacal copper quaternary (ACQ) modified Mongolian Scotch pine wood and untreated Mongolian Scotch pine. The conclusions are as follows:1. Physical properties of the two heat treated woods had been comparatively studied. It was found that after heat treatment, the mass loss of the two heat treated woods were great; the equilibrium moisture contents decreased about 50%; water absorption, radial and tangential full—dry shrinkage, moisture resistance (MEE) rate, the anti-string and expansion rate (ASE), which related to dimension stability were remarkably improved. Heat treatment significantly reduces the tangential and radial swelling, so the wood's swelling and shrinkage is very low.2. Compressive strength parallel to grain, bending strength, modulus of elasticity (MOE), impact bending strength of the two heat treated woods had been comparatively researched with untreated wood and ACQ treated wood, all those quotas of the two heat treated woods decreased a lot. But crystallinity of the two heat treated woods increased.3. Surface properties had been comparatively investigated, the results were as follows: after heat treatment, wood became dark and red, surface gloss decreased, water permeability increased and surface free energy increased. The color stabilities were much better than untreated wood and ACQ treated wood.4. From the infrared spectrum form of samples, we could found heat treatment caused some chemical changes in the wood. From the picture of the electron microscopy, we found that after heat treatment, wood was not smooth, cell walls can been crushed easily and tore easily, material toughness decreased, a number of small crackle can been seen in cell walls. Heat treatment damaged wood cells. This may explain why the mechanical properties of heat treated wood decreased.5. From field durability test, we learned that the two heat treated wood can't resist termites, but can resist bacteria, the anti-bacterial ability have greatly improved. Heat treated wood are good durability materials.6. Treatment condition impacted wood characteristic, different treatment index can lead to different heat treated wood.