Development of New Products and High Value Added Biopolymer from Softwoods by Chemical Modification - Quantitative Variation of Water-soluble Extracts from Coniferous Barks for Tannin-based Adhesives -

화학가공에 의한 침엽수재의 품질귀화 및 고부가 Biopolymer 개발 (I) - 타닌접착제를 위한 침엽수 수피의 수용성 추출물의 양적 변이 -

Extracts from bark have been studied with a view to producing water-proof wood adhesives. Lately many softwoods, such as radiata pine from New Zealand and larch from Siberia, Russia, have been imported and utilized, and their residual barks would be expecting as potential raw materials for something useful chemicals. The great effort toward utilization of bark extractives as a chemical feedstock has been made on a worldwide level. However few report has been done for the utilization of tree bark extractives in Korea. Hot-water extracts were prepared from barks of Japanese larch(Larix leptolepis). Siberian larch(Larix gmelinii) and Radiata pine(Pinus radiata). The effect of various factors, such as particle size, liquor ratio, extraction temperature, and reaction time, on the extractive yields was discussed. Particle sizes affected the hot-water extractives: the finer the particle size, the higher extractives and extract efficiency. Higher temperature and higher liquor ratio were more effective. Extractives from Japanese larch were relatively less than those from Siberian larch and Radiata pine barks. Formaldehyde precipitates was the highest in extractives of Radiata pine barks. It could be concluded that Siberian larch bark was the best raw material for tannin adhesives, because its extractive yield was higher than those of the other barks.