Use of nanocellulose for high performance papermaking products

Transcription

1 Use of nanocellulose for high performance papermaking products Nanopaper LED light Nanopaper 30 September 2014, Arnhem Rauni Seppänen 1

2 Contents Nanocellulose Preparation Properties Nanocellulose producers Patents Advantages Use in papermaking - possibilities Paper strength additive Coating Barrier Nanopaper and other paper products Conclusions 2

3 Nanocelluloses CNC Crystalline nano cellulose CNF Cellulose nano fibrils or CMF Cellulose micro fbrils Zimmermann, Adv. Eng. Mat. 2004,

4 Masuko grinder 4

5 CNF/CMF: Type of functional groups and degree of substitution (DS) after chemical pre-treatments. Treatment Functional group DS References TEMPO/NaBr/NaClO at ph 10 TEMPO/NaClO/NaClO2 at ph 7 Electro-mediated TEMPO oxidation Carboxylate groups Aldehyde groups Carboxylate groups Aldehyde groups Carboxylate groups Aldehyde groups Saito et al. (2006) Saito et al. (2009) Isogai et al. (2011b) Carboxymethylation Carboxylate groups 0.09 Wågberg et al (2008) Cationic modification Quaternary amine groups Aulin et al. (2010); Olszewska et al. (2011) CNC prepared by acid hydrolysis shows usually higher values than above. 5

6 Advantages Natural and renewable Biodegradable Reduced carbon footprint Recyclable Reusable Compostable Biocompatible High surface area Light weight Dimensional stability Thermal stability High optical transparency High thermal conductivity Low oxygen permeability Chemical functionality (after modification) High strength and modulus 6

7 (Pre-)commercial CNF/CNC production facilities, e.g. CelluForce (Domtar/FP Innovations) Canada (CNC) BioVision, Canada, (Nanocel carboxylated CNC) AlPac and AIFT, Canada (CNC) Melodea, Israel (CNC) Borregaard, Norway (NFC) Rettenmaier, Germany (CNF) DaiCel, Japan (CNF) Nippon Paper, Japan, Cellenpia (CNF) Oji Paper, Japan (CNF) Stora Enso, Finland (CNF) UPM-Kymmene, Finland (Biofibrils, CNF) US Forest Products Lab. (CNC) Verso Paper, USA (CNF) 2014: There are more companies, e.g. Norske Skog that have declared their intention to launch CNF- or CNC-production.

8 Patents Nanocellulose Holmen

9 Paper strength additive 9

10 UPM researchers: Nanocellulose increases paper strength properties even at low dosages Good overall runnability Reduction of wire section dewatering Dry solids 1-3%-unit higher after press Section No changes in formation or retention Tensile strength increases (~8g/m2 basis weight reduction) Elastic modulus increases strongly Bending stiffness remains the same 20-30% lower porosity Opacity ~4%-units lower Kajanto, I., Kosonen, M. The potential Use of micro- and nano fibrillated Cellulose as a reinforcing Element in Paper and Board based Packaging. Tappi International Conference on Nanotechnology for Renewable Materials,

11 Paper strength additive addition strategy Mixing of nanocellulose into a papermaking furnish: - directly into the full pulp with or without retention aid - pre-mixed with a certain furnish component such as the filler or long fibre fraction and deposited on the surfaces of this furnish component by retention aids. - preflocculation of the nanocellulose with a retention polymer before addition to sheets and adding the retention aid to the fibre furnish before adding CNF to control if the nanocellulose mainly will be: a) loosely or not bonded to the larger particles in the furnish before dewatering b) retained as a coating layer on one or several of the fractions in the furnish using a suitable retention polymer. 11

12 Paper - Filler Higher filler content lower cost Higher dry and wet strength lower grammage and better optical properties The smaller the diameter of the fibrils, the better they will be successfully enclosed by filler particles (entangled pigment) and form a suitable fibril-filler composite Jens Kretzschmar et al, PST ipw 9/

13 Paper Filler composite - Fibrillated celluloses were added to suspensions of kaolin or calcium carbonate (GCC). - A highly cationic starch was suitable to assist the coupling. Jens Kretzschmar et al, PST, ipw 9/2013, 13

14 Surface image of a sheet composed of 65% TMP, 30% CaCO3 and 5% CNF. Source: Hii et al. (2012) 14

15 Commercial MFC - FiberLean MFC FiberLean MFC highly filled sheet, 4% MFC, 55% GCC FiberLean MFC replaces 10-15% of the fiber in the base paper. The MFC contained in the composite has a large surface area, thus allowing the formation of more hydrogen bonds within the web, giving natural strength to the paper. Source: Imerys FiberLean brochure 15

16 Nanocellulose composite papers = MFC / Pigment / Fiber composites 20% MFC / 70% pigment / 10% BKSW - Improved dewatering by co-precipitating CaCO3 on MFC Halbert Zheng, Juuso Rantanen and Thad Malonay, Fibrillated Cellulose Production Chemically Assisted Disintegration of Fibre Cell Wall, TAPPI Int. Conf. Proceedings, June 2014, Vancouver, Canada. 16

17 Functional Additives Nanocelluloses as Flocculants and Retention Aids Functionalized nanocelluloses as retention aids, combining a large hydrodynamic radius and high collision efficiency (e.g. Link Magazine, KCL, 2/2008) CNF Cationic nanocelluloses as flocculants e.g. retention aids Fiber/fines/filler Applications: Retention aids, wet web strength additives, dry strength additives, water-treatment 17

18 Nanocellulose Application areas, e.g. Ahola et al, Biomacromol Coatings and functional surfaces - Printing papers - Food packaging - New material for electronics Functional membranes / foams - Packaging - Tissue engineering Eichhorn et al

19 Cellulose NANOPAPER: excellent mechanical properties Modulus 14 GPa Strength 214 MPa (typical paper has a strength of 1 MPa. Strength starts to approach that of steel Henriksson, Berglund, Isaksson, Lindström, Nishino, Biomacromolecules 2008, 9, 1579

20 Applications for Nanopaper? - To replace all grocery bags, providing an eco-friendly alternative to petroleum-consuming plastic bags. - Reinforcing agent in plastics in lieu of highly expensive carbon fibers. Nanopaper is riddled with large pores, allowing faster drying, which would decreases the price of any final product that uses it. - Transistors - Magnetic nanopaper - Filter for virus particles - Etc. 20

21 A picture of a fabricated transparent and flexible nanopaper transistor. (Image: Bing Research Group, University of Maryland) 21

22 Magnetic nanopaper composite: Olsson et al. Nat. Nanotechnol. 2010, 5, 584. Magnetic response which can be actuated by a small household magnet Aerogels are dry, lightweight, and porous (98% porosity) Aerogels can absorb water and release it upon compression Tunable mechanical properties for both the nanopaper and the aerogels 22

23 Superhydrophobicity: Self-cleaning bowl and plate of nanocellulose Designers Hanna Billqvist and Anna Glansén developed the prototypes through a collaboration with Innventia and KTH. 23

24 Cellulose nanofiber paper filter removes virus particles with high efficiency March 2014, Uppsala, Sweden The illustration shows the nanofibers in white and the virus in green. Photograph: Björn Syse 24

25 Nano Paper LED lights Guard, Nano Paper lamp wire stand 25

26 Coatings & Functional Surfaces Nanocelluloses as barrier materials Specific advantages: high oxygen barrier, affinity to wood fibers Disadvantage: Moisture sensitive (hydrophobic compound required) Application: Food packaging, printing papers (smooth surfaces, nanocellulose as an organic pigment) Hult et. al, Cellulose, (2010) 26

27 Coating layer: Nanofibrils or xylan coating layer: good: dense and high resistance to air and vapor Can be further modified to increase the hydrophobicity so the water resistance Inorganic nanoclay can be added to the cellulose nanofibrils dense layer to improve air, water and oil resistance Dense coating layer of cellulose nanofibrils: - Low gas gas permittance - Adding high aspect ration clay, modify nanocellulose to further reduce the gas permeability 27

28 Paper packaging has the most favorable properties - Sustainable - Lightweight - Low Cost - Easily transported and stored However, pure cellulose paper does not have barrier properties so it is usually coated by - Plastic - Wax - Aluminum These coating materials limit recyclability of the packaging 28

29 Smooth & transparent films Barrier materials Packages Security papers Nanocellulosic materials have an inherent tendency to form films upon drying Good oxygen barrier materials especially in dry conditions Sensitive towards moisture and water 29

30 Added value from nanocellulose - Increased functionality, improved mechanical properties, novel optical and conductivity properties, light weight high performance structures To tailor the properties of nanocellulose for optimal functionality in different industrial applications. To understand the interactions of nanofibrils with each other and/or other components. NCC, Nano crystalline cellulose NFC, Nano fibrillated cellulose Zimmermann, Adv. Eng. Mat. 2004,

31 Strong and light composites -> packages Binder between two organic phases -> improves break strength and prevents crack propagation Juntaro J, et. al (2008) Adv Mater 20:

32 Conclusions CNF works well as a dry strength additive in papermaking -CNF must be reasonably well degraded/good retention aid system -> Density increases -> Permeability decreases -> Opacity and brightness decrease -Lower addition levels in industry to avoid increased dewatering time in the wire section -Higher filler content possible -Best for mechanical, recycled and unbeaten chemical pulp CNF in coating needs to be studied more in detail CNF good oxygen barrier Preparation cost of nanocelluloses decreases 32

33 Examples of chemical modifications 33

34 Hydrophobic surface by palmitoyl chloride Berlioz et al. Biomacromolecules 2009, 10,