| This thesis studied on the technology and mechanisms of bamboo chemimechanical pulpingwith white-rot fungi pretreatment.Firstly, the optimum conditions of fungi were discussed including temperature, pH, nutrientsupplements, and aeration. Trametes hirsuta (Th19-6) was selected for a faster growing, ahigher dilignification ability and better delignification selectively than the other white-rotfungi. Pretreatment of bamboo chips with lignin-degrading fungi Trametes hirsuta (Th19-6)can improve the strength properties of unbleached mechanical pulp. The pulp and paperproperties were evaluated after fungal pretreatment. Strength and optical properties werecompared in handsheets prepared from chemimechanical pulp of treated and untreatedbamboo chips. Comparing to the control pulp, the tensile index, burst index and internalbonding were increased by 18.71ï¼…, 12.6ï¼…and 12.7ï¼…, respectively. However, the tear indexwas reduced a little and no particular Change was observed in zero-span strength. Fungalpretreatment resulted better in pulp strength properties than the control sample. According topulp fiber quality analysis, fungal pretreatment increased the fiber length and reduced thefines contents.A light microscopy and electron microscopes (SEM and TEM) were also used to identify thechips cell wall and pulp morphology changes brought by fungal pretreatment. The cell wallchanges of bamboo chips indicated that white-rot fungi can selectively degrade or modifynative lignin in bamboo, which can facilitate lignin removal or softening in subsequentpulping process. The biomechanical pulp appeared more fibrillation, looser, woolly than control pulp fibers. Changes in fiber surface and internal cell wall structure were contributedto the strength properties improvement.
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