Imaging of the formerly bonded area of individual fibre to fibre joints with SEM and AFM
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Besides the determination of the force and the energy needed to break individual fibre to fibre joints, the investigation of the formerly bonded area (FBA) is of essential importance to learn more about the failure mechanisms of fibre–fibre bonds in general. In this study the surfaces of paper fibres and the FBA of fibre–fibre joints after the determination of the breaking force as well as the bonding energy were analysed by means of low voltage scanning electron microscopy and atomic force microscopy. A comparison between the contact zone of fibres broken at different loading rates as well as under cyclic loading showed that there seems to be no significant difference in the appearance of the FBA in these cases. Only minor delamination of the cell wall could be found in the bonding zone, which indicates no mechanical interlocking of fibrils in the bonding zone. Furthermore, it is shown that some glues used for specimen preparation of fibre–fibre bond strength measurement are forming a glue film on the fiber surface and migrate into the bonding region.
KeywordsFibre to fibre joint Joint strength Bonding energy Formerly bonded area (FBA) Low voltage scanning electron microscopy (LVSEM) Atomic force microscopy (AFM)
The Authors want to thank Mondi, the Austrian Federal Ministry of Economy, Family and Youth and the National Foundation for Research, Technology and Development.
- Jayme G, Hunger G (1961) Electron microscopy 2- and 3-dimensional classification of fibre bonding. In: Bolam F (ed) Formation and structure of paper—transaction of the IIth fundamental research symposium held at Oxford, pp 135–170Google Scholar
- Kang T, Paulapuro H, Hiltunen E (2004) Fracture mechanism in interfibre bond failure—microscopic observations. Appita J 57(3):199–203Google Scholar
- Li K, Lei X, Lu L, Camm C (2010) Surface characterization and surface modification of mechanical pulp fibres. Pulp Pap Can 111(1):T11–T16Google Scholar
- Lindström T, Wågberg L, Larsson T (2005) On the nature of joint strength in paper—a review of dry and wet strength resins used in paper manufacturing. In: Advances in paper science and technology—transactions of the 13th fundamental research symposium held at Cambridge, pp 457–562Google Scholar
- Mayhood CH, Kallmes OJ, Cauley MM (1962) The mechanical properties of paper part II. Measured shear strength of individual fiber to fiber contacts. Tappi J 45(1):69–73Google Scholar
- Page DH (1969) A theory for the tensile strength of paper. Tappi J 52(4):674–681Google Scholar
- Persson BNJ, Ganser C, Schmied FJ, Teichert C, Schennach R, Gilli E, Hirn U (2013) Adhesion of cellulose fibers in paper. J Phys Condens Matter 25(4):045002Google Scholar
- Reimer L (1993) Image formation in low-voltage scanning electron microscopy. SPIE-Press, Bellingham, WashingtonGoogle Scholar
- Saketi P, Kallio P (2011) Measuring bond strength of individual paper fibers using microrobotics. In: Hirn U (ed) Progress in paper physics seminar 2011. Verlag der Technischen Universität Graz, Graz, pp 199–203Google Scholar
- Schmied F, Teichert C, Kappel L, Hirn U, Schennach R, Schröttner H (2009) Comparative AFM and SEM investigations on kraft pulp fiber surfaces. In: Kothleitner G, Leisch M (eds) Instrumentation and methodology, pp 299–300Google Scholar
- Stratton RA, Colson NL (1990) Dependence of fiber/fiber bonding on some papermaking variables. Technical Report IPST Technical Paper Series. Number 357, Institute of Paper Science and Technology Atlanta, GeorgiaGoogle Scholar