| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide purified lignin suitable as a raw material for synthetic resin raw material, especially for epoxy resin raw material, or an epoxy resin with a high content of vegetable raw material, further more excellent in mechanical performance. <P>SOLUTION: The purified lignin of poaceous plants is obtained by acidifying pulp effluents by an alkali digestion method using poaceous plants as raw materials, and thus obtained lignin of a poaceous plant is separated into hydrophilic organic solvent soluble part and insoluble part, and the insoluble part is removed, thereby recovering only the soluble part. The epoxy resin including 60 wt.% or more of the lignin is obtained by reacting the lignin of a poaceous plant with epichlorohydrin. The hardened epoxy resin is obtained by hardening an epoxy resin with the purified lignin of a poaceous plant as a curing agent and includes 30% or more of the lignin. <P>COPYRIGHT: (C)2013,JPO&INPIT |
