生物酶预处理对秸秆中密度纤维板性能的影响

针对稻草和麦秸原料的特点,分别用木聚糖酶、漆酶／碳源系统(LCS)和脂肪酶对原料进行生物酶预处理用机械磨浆方法制备纤维,以木质纤维板用脲醛树脂作胶黏剂,压制秸秆中密度板,并探讨酶处理对秸秆纤维板性能的影响。结果表明:各种生物酶预处理对稻草和麦秸纤维板的性能都有一定的改善,同软化处理相比,经三种生物酶处理后的长纤维的比例明显增加,而细小纤维的含量则明显降低,IB均有不同程度的改进,其中木聚糖酶对此两项指标的改进效果更好。经木聚糖酶预处理后压制的密度达到0．8 g／cm3以上的纤维板的性能如下:麦草纤维板的IB为0．75 MPa,MOE为3 960 MPa,MOR为37．60 MPa,TS为21．29％。除TS外,均优于GB／T11718-1999标准要求。而稻草纤维板的IB为0．73 MPa,MOE为2 618 MPa,MOR为21．35 MPa,TS为21．19％,其中MOR与TS均离标准要求还有一定的差距。

Effect of Enzymes Pretreatment on Performances of Straw-based MDF

UF bonded straw-based MDF with density of 0. 8 g/cm3 was made from straw fibers pretreated with xylanase,Laccase/carbon source system(LCS)and lipase respectively, and the influences of the enzymes on performances of the MDF were investigated The results were as follows: Pretreatment with any of the 3 kinds of enzymes could improve performances of the straw-based MDF prepared, and xylanase had the best effect of them. After treatment, the ratio of long fibers increased while the ratio of minor fibers decreasd,and the IB of the MDF was improved as compared with contrast panel. Except thickness swelling of 21. 29% was not satisfactory,the IB of 0. 75 MPa,MOE of 3 960 MPa and MOR of 37. 60 MPa of the MDF made from xylanase treated wheat straw were all higher than requirements specified in GB/T11718-1999,and the properties of the MDF made from xylanase treated rice straw were poorer with IB of 0. 73 MPa,MOE of 2 618 MPa, MOR of 21. 35 MPa and TS of 21.19%.