Study On The Drying Characteristic Of Resin-impregnated Chinese Fir

With the implementation of Natural Forest Protection Project, Chinese fir has became to be the priority tree species. The disadvantages of Chinese fir such as low density and poor dimension stability limit its utilization. And value-added use of Chinese fir has become to be the focus of domestic production enterprises and scientific research institutions. This dissertation studied on the drying characteristic, dimensional stability and moisture absorption characteristic of the Chinese fir which was impregnated with low molecular weight water soluble phenol formaldehyde resin. The results are as follows:(1)The vacuum-pressure resin impregnation treatment parameters of Chinese fir timber with large size were: resin concentration: 20%,vacuum keeping time:60min,pressure:1.0Mpa, pressure keeping time:3 hours. Chinese fir timber was treated and the weight increase rate was 34.62%.(2)This dissertation studied the drying characteristic of Chinese fir timber and compare with the untreated wood with the same moisture content by 100℃experiment. The drying schedule for the resin treated Chinese fir was established The temperature of the drying schedule of treated wood is about 2℃～4℃higher than the one of untreated wood. And this drying schedule was optimized.(3)This paper studied on the shrinkage, water absorption and swelling of treated Chinese fir and untreated Chinese fir. The study showed that dimensional stability of the treated Chinese fir was much better than the dimensional stability of the untreated wood.(4)The sorption hysteresis of the treated Chinese fir was studied in the paper. The study showed that treated Chinese fir had sorption hysteresis phenomena. Compared with which of the untreated wood, the absorption and desorption of the treated wood was less affected.