Drying of Pigment-Cellulose Nanofibril Substrates

Materials

Oleg Timofeev²  Katariina Torvinen²  Jenni Sievänen²  Timo Kaljunen²  Jarmo Kouko²  Jukka A. Ketoja¹ 

[1] VTT Technical Research Centre of Finland, P. O. Box 1000, FI-02044 VTT, Finland;

关键词: cellulose nanofibril;    substrate;    drying;    evaporation;    surface;    material property;   

DOI  :  10.3390/ma7106893

来源: mdpi

【 摘 要 】

A new substrate containing cellulose nanofibrils and inorganic pigment particles has been developed for printed electronics applications. The studied composite structure contains 80% fillers and is mechanically stable and flexible. Before drying, the solids content can be as low as 20% due to the high water binding capacity of the cellulose nanofibrils. We have studied several drying methods and their effects on the substrate properties. The aim is to achieve a tight, smooth surface keeping the drying efficiency simultaneously at a high level. The methods studied include: (1) drying on a hot metal surface; (2) air impingement drying; and (3) hot pressing. Somewhat surprisingly, drying rates measured for the pigment-cellulose nanofibril substrates were quite similar to those for the reference board sheets. Very high dewatering rates were observed for the hot pressing at high moisture contents. The drying method had significant effects on the final substrate properties, especially on short-range surface smoothness. The best smoothness was obtained with a combination of impingement and contact drying. The mechanical properties of the sheets were also affected by the drying method and associated temperature.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.