Explanation
Also known as lignin, it is a natural polymer organic compound, accompanied with cellulose. It exists in the cell wall of wood. The intercellular layer between cells is mainly formed by it, and it forms crusts with semi cellulose to enhance the strength of the cell wall. It is a unique chemical component of gymnosperms and angiosperms. The distribution of lignin in wood is uneven, and it changes significantly with different tree species, tree ages, and tree parts. The lignin content in wood is 20% -40%. lignin is complex in composition, low in chemical stability, and susceptible to acid, alkali, oxidizer, halide, etc. Industrial output is mainly obtained from pulping waste liquid. In industry, it uses its activity to remove lignin from wood to obtain cellulose. The pulping process uses this principle that lignin is a thermoplastic polymer with no obvious melting point. The fiber is plasticized by heated wood, which can promote the separation of fibers. fiberboard production uses this principle to separate fibers by hot grinding and produce fiberboard and particleboard by using the plasticizing properties of lignin under high temperature and pressure. lignin is widely used as fuel, dye or dyestuffc, pigment, carbon black, dispersing agent for cement and drilling mud, graphite, adhesive for iron ore, reinforcing agent and antioxidant for rubber. lignin is also used as an auxiliary material for manufacturing plastics, resin, etc.
Classification
Natural materials and products -> Wood and bamboo materials -> Wood