Customizing the mechanical performance of water stable TEMPO oxidized cellulose nanofibril films

Minna Hakalahti, Arto Salminen, Jukka Seppälä, Tekla Tammelin, Tuomas Hänninen

Research output: Contribution to conferenceConference articleScientific

Abstract

Hygroscopic nature of cellulose is one of the most difficult limiting factors to overcome in utilization of nanocellulose. When unmodified nanocellulose structure is subjected to humidity or immersed in water it loses its structural integrity very quickly. Nanoscaled cellulose fibrils form very tightly packed films, which can be used, for example, as excellent barriers or membranes. Water stability of nanocellulose films has been improved by preparation of multilayered structures, reduction of free volume, surface modification and additives. Polyvinyl alcohol (PVA) can be used to significantly enhance water stability of films prepared from TEMPO oxidized cellulose nanofibrils (TOCNs). In water swollen TOCN films, PVA has two functions; it can either improve the wet strength by forming interfibrillar bridges or act as a plasticizer. The interfibrillar bridging is result of two mechanisms (Fig. 1): 1) hemiacetal bonding between PVA hydroxyls and aldehydes in TOCNs and 2) acid catalysed formation of ester bonds between PVA hydroxyls and carboxylic groups in TOCNs. Sufficient bonding between TOCNs to achieve water stability could not be observed. Mechanical properties of the films can be tuned without losing the water stability merely by changing the amount of PVA. Even after being immersed in water for several months, TOCN/PVA films maintain their structural integrity. The water stability increases to such extent that TOCN/PVA films can be used as water filtration membranes.
Original languageEnglish
Publication statusPublished - 2015
EventInternational Symposium on Wood Science and Technology, IAWPS 2015 - Tokyo, Japan
Duration: 15 Mar 201517 Mar 2015

Conference

ConferenceInternational Symposium on Wood Science and Technology, IAWPS 2015
Abbreviated titleIAWPS
CountryJapan
CityTokyo
Period15/03/1517/03/15

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oxidized cellulose
Cellulose films
Polyvinyl Alcohol
Water
Structural integrity
Cellulose
Hydroxyl Radical
Water filtration
Membranes
Plasticizers
TEMPO
Free volume
Aldehydes
Surface treatment
Atmospheric humidity
Esters
Mechanical properties

Cite this

Hakalahti, M., Salminen, A., Seppälä, J., Tammelin, T., & Hänninen, T. (2015). Customizing the mechanical performance of water stable TEMPO oxidized cellulose nanofibril films. Paper presented at International Symposium on Wood Science and Technology, IAWPS 2015, Tokyo, Japan.
Hakalahti, Minna ; Salminen, Arto ; Seppälä, Jukka ; Tammelin, Tekla ; Hänninen, Tuomas. / Customizing the mechanical performance of water stable TEMPO oxidized cellulose nanofibril films. Paper presented at International Symposium on Wood Science and Technology, IAWPS 2015, Tokyo, Japan.
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abstract = "Hygroscopic nature of cellulose is one of the most difficult limiting factors to overcome in utilization of nanocellulose. When unmodified nanocellulose structure is subjected to humidity or immersed in water it loses its structural integrity very quickly. Nanoscaled cellulose fibrils form very tightly packed films, which can be used, for example, as excellent barriers or membranes. Water stability of nanocellulose films has been improved by preparation of multilayered structures, reduction of free volume, surface modification and additives. Polyvinyl alcohol (PVA) can be used to significantly enhance water stability of films prepared from TEMPO oxidized cellulose nanofibrils (TOCNs). In water swollen TOCN films, PVA has two functions; it can either improve the wet strength by forming interfibrillar bridges or act as a plasticizer. The interfibrillar bridging is result of two mechanisms (Fig. 1): 1) hemiacetal bonding between PVA hydroxyls and aldehydes in TOCNs and 2) acid catalysed formation of ester bonds between PVA hydroxyls and carboxylic groups in TOCNs. Sufficient bonding between TOCNs to achieve water stability could not be observed. Mechanical properties of the films can be tuned without losing the water stability merely by changing the amount of PVA. Even after being immersed in water for several months, TOCN/PVA films maintain their structural integrity. The water stability increases to such extent that TOCN/PVA films can be used as water filtration membranes.",
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Hakalahti, M, Salminen, A, Seppälä, J, Tammelin, T & Hänninen, T 2015, 'Customizing the mechanical performance of water stable TEMPO oxidized cellulose nanofibril films' Paper presented at International Symposium on Wood Science and Technology, IAWPS 2015, Tokyo, Japan, 15/03/15 - 17/03/15, .

Customizing the mechanical performance of water stable TEMPO oxidized cellulose nanofibril films. / Hakalahti, Minna; Salminen, Arto; Seppälä, Jukka; Tammelin, Tekla; Hänninen, Tuomas.

2015. Paper presented at International Symposium on Wood Science and Technology, IAWPS 2015, Tokyo, Japan.

Research output: Contribution to conferenceConference articleScientific

TY - CONF

T1 - Customizing the mechanical performance of water stable TEMPO oxidized cellulose nanofibril films

AU - Hakalahti, Minna

AU - Salminen, Arto

AU - Seppälä, Jukka

AU - Tammelin, Tekla

AU - Hänninen, Tuomas

PY - 2015

Y1 - 2015

N2 - Hygroscopic nature of cellulose is one of the most difficult limiting factors to overcome in utilization of nanocellulose. When unmodified nanocellulose structure is subjected to humidity or immersed in water it loses its structural integrity very quickly. Nanoscaled cellulose fibrils form very tightly packed films, which can be used, for example, as excellent barriers or membranes. Water stability of nanocellulose films has been improved by preparation of multilayered structures, reduction of free volume, surface modification and additives. Polyvinyl alcohol (PVA) can be used to significantly enhance water stability of films prepared from TEMPO oxidized cellulose nanofibrils (TOCNs). In water swollen TOCN films, PVA has two functions; it can either improve the wet strength by forming interfibrillar bridges or act as a plasticizer. The interfibrillar bridging is result of two mechanisms (Fig. 1): 1) hemiacetal bonding between PVA hydroxyls and aldehydes in TOCNs and 2) acid catalysed formation of ester bonds between PVA hydroxyls and carboxylic groups in TOCNs. Sufficient bonding between TOCNs to achieve water stability could not be observed. Mechanical properties of the films can be tuned without losing the water stability merely by changing the amount of PVA. Even after being immersed in water for several months, TOCN/PVA films maintain their structural integrity. The water stability increases to such extent that TOCN/PVA films can be used as water filtration membranes.

AB - Hygroscopic nature of cellulose is one of the most difficult limiting factors to overcome in utilization of nanocellulose. When unmodified nanocellulose structure is subjected to humidity or immersed in water it loses its structural integrity very quickly. Nanoscaled cellulose fibrils form very tightly packed films, which can be used, for example, as excellent barriers or membranes. Water stability of nanocellulose films has been improved by preparation of multilayered structures, reduction of free volume, surface modification and additives. Polyvinyl alcohol (PVA) can be used to significantly enhance water stability of films prepared from TEMPO oxidized cellulose nanofibrils (TOCNs). In water swollen TOCN films, PVA has two functions; it can either improve the wet strength by forming interfibrillar bridges or act as a plasticizer. The interfibrillar bridging is result of two mechanisms (Fig. 1): 1) hemiacetal bonding between PVA hydroxyls and aldehydes in TOCNs and 2) acid catalysed formation of ester bonds between PVA hydroxyls and carboxylic groups in TOCNs. Sufficient bonding between TOCNs to achieve water stability could not be observed. Mechanical properties of the films can be tuned without losing the water stability merely by changing the amount of PVA. Even after being immersed in water for several months, TOCN/PVA films maintain their structural integrity. The water stability increases to such extent that TOCN/PVA films can be used as water filtration membranes.

M3 - Conference article

ER -

Hakalahti M, Salminen A, Seppälä J, Tammelin T, Hänninen T. Customizing the mechanical performance of water stable TEMPO oxidized cellulose nanofibril films. 2015. Paper presented at International Symposium on Wood Science and Technology, IAWPS 2015, Tokyo, Japan.