Khakalo Alexey, Mäkelä Tapio, Johansson Leena-Sisko, Orelma Hannes, Tammelin Tekla
VTT Technical Research Centre of Finland Ltd., Tietotie 4E, P.O. Box 1000, FI-02044 Espoo, Finland.
VTT Technical Research Centre of Finland Ltd., Tietotie 3, FI-02150 Espoo, Finland.
ACS Appl Bio Mater. 2020 Nov 16;3(11):7428-7438. doi: 10.1021/acsabm.0c00576. Epub 2020 Oct 29.
This paper demonstrates a high-throughput approach to fabricate nanocellulose films with multifunctional performance using conventionally existing unit operations. The approach comprises cast-coating and direct interfacial atmospheric plasma-assisted gas-phase modification along with the microscale patterning technique (nanoimprint lithography, NIL), all applied in roll-to-roll mode, to introduce organic functionalities in conjunction with structural manipulation. Our strategy results in multifunctional cellulose nanofibrils (CNF) films in which the high optical transmittance (∼90%) is retained while the haze can be adjusted (2-35%). Concomitantly, the hydrophobic/hydrophilic balance can be tuned (50-21 mJ/m with the water contact angle ranging from ∼20 up to ∼120°), while intrinsic hygroscopicity of CNF films is not significantly compromised. Therefore, a challenge to produce multifunctional bio-based materials with properties defined by various high-performance applications conjoined to the lack of efficient processing strategies is elucidated. Overall, economically and ecologically viable strategy, which was realized by facile and upscalable unit operations using the R2R technology, is introduced to expand the properties' spaces and thus offer a vast variety of interesting applications for CNF films.
本文展示了一种利用常规现有单元操作制备具有多功能性能的纳米纤维素薄膜的高通量方法。该方法包括流延涂布和直接界面常压等离子体辅助气相改性以及微尺度图案化技术(纳米压印光刻,NIL),所有这些都以卷对卷模式应用,以结合结构操纵引入有机功能。我们的策略产生了多功能纤维素纳米原纤维(CNF)薄膜,其中在保持高透光率(约90%)的同时可以调节雾度(2%-35%)。同时,可以调节疏水/亲水平衡(50-21 mJ/m²,水接触角范围从约20°到约120°),而CNF薄膜的固有吸湿性不会受到显著影响。因此,阐明了在缺乏有效加工策略的情况下,生产具有各种高性能应用所定义性能的多功能生物基材料所面临的挑战。总体而言,引入了一种经济且生态可行的策略,该策略通过使用R2R技术的简便且可扩大规模的单元操作实现,以扩展性能空间,从而为CNF薄膜提供各种各样有趣的应用。