Hwang Sungjun, Walker Colleen C, Johnson Donna, Han Yousoo, Gardner Douglas J
Advanced Structures and Composites Center, University of Maine, 35 Flagstaff Road, Orono, ME 04469-5793, USA.
School of Forest Resources, University of Maine, 5755 Nutting Hall, Orono, ME 04469-5755, USA.
Polymers (Basel). 2023 Oct 14;15(20):4086. doi: 10.3390/polym15204086.
Enzyme-treated cellulose nanofibrils (CNFs) were produced via a lab-scale mass colloider using bleached kraft pulp (BKP) to evaluate their processability and power requirements during refining and spray-drying operations. To evaluate the energy efficiency in the CNF refining process, the net energy consumption, degree of polymerization (DP), and viscosity were determined. Less energy was consumed to attain a given fines level by using the endoglucanase enzymes. The DP and viscosity were also decreased using the enzymes. The morphological properties of the enzyme-pretreated spray-dried CNF powders (SDCNFs) were measured. Subsequently, the enzyme-pretreated SDCNFs were added to a PP matrix with MAPP as a coupling agent. The mixture was then compounded through a co-rotating twin-screw extruder to determine whether the enzyme treatment of the CNFs affects the mechanical properties of the composites. Compared to earlier studies on enhancing PMCs with SDCNF powders, this research investigates the use of enzyme-pretreated SDCNF powders. It was confirmed that the strength properties of PP increased by adding SDCNFs, and the strength properties were maintained after adding enzyme-pretreated SDCNFs.
采用实验室规模的均质器，以漂白硫酸盐浆（BKP）为原料制备了酶处理纤维素纳米纤维（CNFs），以评估其在细化和喷雾干燥操作过程中的加工性能和能量需求。为了评估CNF细化过程中的能源效率，测定了净能耗、聚合度（DP）和粘度。使用内切葡聚糖酶达到给定的细粉水平时消耗的能量更少。使用这些酶后，DP和粘度也降低了。测量了酶预处理喷雾干燥CNF粉末（SDCNFs）的形态特性。随后，将酶预处理的SDCNFs与作为偶联剂的MAPP一起添加到PP基体中。然后通过同向旋转双螺杆挤出机对混合物进行混合，以确定CNFs的酶处理是否会影响复合材料的机械性能。与早期关于用SDCNF粉末增强PMC的研究相比，本研究调查了酶预处理SDCNF粉末的使用情况。结果证实，添加SDCNFs可提高PP的强度性能，添加酶预处理的SDCNFs后强度性能得以保持。
