• Journal of the Korean Wood Science and Technology
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• 제50권6호
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• pp.436-447
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• 2022

Lignocellulose nanofibrils (LCNFs) were prepared using a two-step deep eutectic solvent (DES) and enzymatic pretreatment followed by mechanical defibrillation, and we examined the effects of enzymatic pretreatment conditions on different characteristics of the LCNFs thus obtained. The LCNFs yielded using the two-step DES pretreatment (Enz-LCNF) exhibited a well-defibrillated entangled web-like structure with an average fiber diameter ranging from 15.7 to 20.4 nm. Furthermore, we found that the average diameter and filtration time of the Enz-LCNFs decreased with an increase in enzyme concentration and enzymatic treatment time, whereas we detected a concomitant reduction in the tensile strength of the Enz-LCNF sheets. The Enz-LCNFs were characterized by a typical cellulose I structure, thereby indicating that the enzymatic treatment causes very little damage to the crystalline form.

• Journal of the Korean Wood Science and Technology
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• 제45권3호
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• pp.268-277
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• 2017

본 연구는 리그노셀룰로오스의 주성분 용해에 우수하다고 알려진 이온성 액체인 1-ethyl-3-methylimidazolium acetate ([EMIM]Ac)와 셀룰로오스와 친화성이 있는 유기용매인 dimethylformamide (DMF)의 혼합용매를 이용하여 갯버들 목분을 처리한 후, 디스크밀 해섬에 의한 리그노셀룰로오스 나노섬유를 제조하고 그 특성을 평가하였다. 무처리샘플과 DMF 및 [EMIM]Ac가 10과 30% 포함된 혼합용매로 목분의 고형분량을 15%로 선정하였다. 전처리물의 X선 회절도로부터 모든 샘플이 셀룰로오스 I의 패턴을 나타냈으며, 상대결정화도는 [EMIM]Ac가 30% 포함된 혼합용매로 2시간 처리한 전처리물이 가장 낮았다. 무처리 및 DMF와 [EMIM]Ac가 10% 포함된 혼합용매로 처리한 전처리물의 평균결정크기는 약 3.2 nm였으며, [EMIM]Ac가 30%까지 포함되고 처리 시간이 경과할수록 다소 감소하는 경향을 나타내었다. 혼합용매의 사용을 통한 전처리물의 목재세포벽 구조의 완화로 해섬 효율이 향상되었으며, 전처리 시간 및 해섬 시간이 경과할수록 비표면적이 증가하는 경향을 나타내었다.

• Journal of the Korean Wood Science and Technology
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• 제45권6호
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• pp.737-745
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• 2017

This study was carried out to investigate the changes in micro- and nanoscopic morphology of cellulose nanofibrils (CNFs) from various bioresources by investigating various mechanical milling systems. Mechanical milling in herbaceous bioresources was more effective than in woody bioresources, demonstrating lower energy consumption and finer morphology. The milling time to reach nanoscopic size was longer in woody bioresources than in herbaceous bioresources. Furthermore, at the same level of wet disk milling time, CNFs from herbaceous bioresources showed more slender morphology than those from woody bioresources. Tensile properties of nanopaper prepared from CNFs of herbaceous bioresources were higher than those of woody bioresources. The highest tensile strength was found to be 77.4 MPa in the nanopaper from Evening prim rose.