Application of filled microcapsules in coatings to provide a self-healing effect

Transcription

1 European Coatings CONFERENCE Functional coatings 06 June 2012 Application of filled microcapsules in coatings to provide a self-healing effect Dipl.-Ing. (FH) Sabine Scharf Klebtechnik und Oberflächen

2 Locations in Germany Itzehoe Lübeck Rostock 60 institutes employees Topics of research Healthy Safety Communication Mobility Energy Environment Partner Industrial enterprises Service industry Public authorities St. Ingbert Saarbrücken Bremerhaven Karlsruhe Pfinztal Freiburg Efringen- Kirchen Bremen Oberhausen Dortmund Duisburg Schmallenberg St. Augustin Aachen Euskirchen Darmstadt Würzburg Erlangen Kaiserslautern Stuttgart Hannover Braunschweig Fürth Halle Schkopau Ilmenau Nürnberg Freising Potsdam Magdeburg Jena München Leipzig Chemnitz Holzkirchen Berlin Teltow Cottbus Dresden

3 Fraunhofer Institute for Manufacturing Technology and Advanced Materials (IFAM) Fraunhofer IFAM, Bremen Adhesive bonding and surfaces Shaping and Functional Materials Adhesive bonding Coating processes Surfaces with defined properties Metals, Metalpowders Electromobility High Performance Sintered Materials

4 Department Paint Technology Development / Raw Materials Functional Coatings Application technology / process engineering Tests methods Failure analysis Qualification of raw materials Investigation of raw materials Development of formulations Development of functional coatings: - Anti-Ice - Anti-Drag - Micro-structuring and Nano-structuring - Self-Healing - Anti-Fouling Pre-treatment / cleaning Support for production Qualification / characterization of coatings Application and drying technologies Development of applicationoriented test methods Aging tests Natural outside weathering

5 Functional coatings Anti-fouling - coatings Micro- and nanostructured coatings Highly abrasive-resistant coatings Anti-contaminationcoatings Anti-icing - coatings

6 Functional coatings Anti-fouling - coatings Micro- and nanostructured coatings Highly abrasive-resistant coatings Anti-contaminationcoatings Self-healing coatings Anti-icing - coatings

7 What are self-healing coatings? Coatings which have the ability to repair damages autonomously No procedures like grinding or recoating necessary Alternative names: self-repairing coatings, autonomous healing coatings

8 Possible classification of self-healing coatings Type of self-healing Use of additives Filled nano-/ microcapsules Filled hollow fibres Filled channels Filled nanoclays Intrinsic healing polymers Modified polymers Trigger to initiate the selfhealing effect Mechanical trigger Thermal trigger ph variation Light induced Electrically induced

9 Self-healing with filled channels 1 / filled fibres 2 Filled channels Moulding of channels with paraffine (diameter 300 µm) Implementation in the matrix Removing paraffine Filling the channels with healingagents Filled fibres Filled with an epoxy-system (resin, hardener) Hollow fibres with a diameter of 60 µm are incorporated into an epoxy matrix The componentes leak when a crack occurs and react 1 D. Therriault, S.R. White, J.A. Lewis; Chaotic mixing in threedimensional micro vascular networks fabricated by direct-write assembly ; Nature Materials 2 (2003) Jody W.C. Pang, *Dr. Ian P. Bond A hollow fibre reinforced polymer composite encompassing self-healing and enhanced damage visibility Composites Science and Technology 65 (2005)

10 Self-healing with filled microcapsules 3 First paper of filled microcapsules for composites from White, et. al 2001 Urea-formaldehyde-microcapsules DCPD as healing agent with a Grubb`s catalyst When a crack occurs, the microcapsules break and the healing agent leaks into the crack and polymerises 3 White, S.R.; Sottos, N.R.; Geubelle, P.H.; Moore, J.S.; Kessler, M.R.; Sriram, S.R.; Brown, E.N.; Viswanathan, S. Autonomic healing of polymer composites, Nature, 409, 2001,

11 Manufacturing of urea-formaldehyde microcapsules Manufacturing of microcapsules possible in lab-scale and industrial scale Commercial available Possible applications: Carbon copy paper Softener Phase-Change microcapsules for climate control of buildings

12 Urea-formaldehyde microcapsules Microscopic pictures of microcapsules; left: intact microcapsule; right: damaged microcapsule with leaking healing agent

13 Absorbance Units IR-Spectroscopy of microcapules Intact capsule Wavenumber cm-1 F:\Messungen\kow\yb\lack.2 Kapsel 1 08/16/11 14:29:37 Measured - A411 Capsule F:\Messungen\kow\yb\lack.3 Kapsel 2 08/16/11 14:41:23 - A411 Measured Capsule 2 Y:\Messungen bis \kow\2006\A406160\Mikrokapseln\bis \Harnstoff_Formaldehyd_Copolymer.0 F:\Messungen\kow\jill\beckopoxep117.0 Beckopox EP Wall 117 material 08/16/11 of the 14:50:45 microcapsule - A Seite 1 von 1 Healing agent /08/ /08/2011 Harnstoff - Formaldehyd Copolym /08/2011 Damaged capsule

14 Model coating with filled microcapsules PUR-coating with filled microcapsules Mock U., Tillner, S., Stenzel, V. Self-healing concepts for protective coatings, Proceedings Nürnberg Congress 2007.

15 Model coating with filled microcapsules After 0 s After 20 s PUR-coating filled with microcapsules; left: 0 seconds and right 20 seconds after damage with a scalpel Mock U., Tillner, S., Stenzel, V. Self-healing concepts for protective coatings, Proceedings Nürnberg Congress 2007.

16 Model coating with filled microcapsules SEM-pictures of a coating with microcapsules

17 EU funded research project ThroughLife European project founded in the FP7 call Duration 36 months / partners from 9 countries Total budget 3,574,975 EURO EU contribution 2,532,364 EURO Coordinator: Mr. Markus Elfgen, MEYER WERFT GmbH ThroughLife includes both New business models New technologies Generic Approach Develop business models that open up new business opportunities for shipyards and ship owners Technological approach Develop maintenance friendly technologies for marine applications Practical approach To test the project results in real life application cases

18 EU funded research project ThroughLife Shipyards Consulting companies, research institutes and organizations Ship owner University Membership organizations Composite company In total 17 partners from 9 countries

19 EU funded research project ThroughLife The main objective of the project is to develop and demonstrate new approaches for through-life asset management for selected technologies, which protect ship structures from corrosion and other degradation effects. New technologies: Condition monitoring Anti-corrosive steels Composites Self-healing coatings Safinah Ltd Star crack in a ballast tank formed by reverse impact from grab

20 EU funded research project ThroughLife Benefits of self-healing coatings for ballast water tanks: Protection of the substrate from corrosion by healing even non visible cracks Stop of the crack growth Encapsulated corrosion inhibitors are released when a crack occurs and protect the substrate against corrosion Prolongation the maintenance cycles and the life span of modules in the ship building Reduction of costs for maintenance and repair

21 EU funded research project ThroughLife Filled microcapsules incorporated in the model coating Healing agents leaks into the crack

22 Combination of self-healing and damage-indicating Fluorescence-labeled microcapsules

23 Further researched healing agents Methyl-methacrylate with suitable catalyst 5 Bisphenol-A epoxy with latent hardener incorporated in the coating matrix, temperatures above 120 C neccessary 6 Linseed oil, that dries oxidative 7 Isophoron-diisocyanate (IPDI), cross-linking without any catalyst via air humidy 8 Epoxy-resins curable with polythiols 9 Polydimethylsiloxane (PDMS), reaction between hydroxy-functional polydimethylsiloxane (HOPDMS) with polydiethoxysiloxane (PDES) 10 5 He, X.; Shi, X, Self-repairing coating for corrosion protection of aluminium alloys, Progress in Organic Coatings, 65, 2009, Yin, T.; Rong, M.Z.; Zhang, M.Q., Yang, G.C., Self-healing epoxy composites Preparation and effect of the healant consisting of microencapsulated epoxy and latent curing agent Composites Science and Technology, 67, 2007, Suryanarayana, C.; Rao, K.C.; Kumar, D., Preparation and characterisation of microcapsules containing linseed oil and ist use in selfhealing coatings, Progress in Organic Coatings, 63, 2008, Yang, J.; Keller, M.W.; Moore, J.S.; White, S.R.; Sottos, N.R., Microencapsulation of isocyanates for self-healing polymers, Macromolecules, 41, 2008, Yuan, Y.C; Rong, M.Z.; Zhang, M.Q., Preparation and characterization of microencapsulated polythiol, Polymer, 49, 2008, Cho, H.S; Andersson, H.M.; White, S.R.; Sottos, N.R.; Braun, P.V., Polydimethylsiloxane-based self-healing materials, Advanced Materials 18, 2006,

24 Conclusion about the self-healing with microcapsules It is possible to formulate self-healing coatings with filled microcapsules Microcapsules can be adapted to different coating materials Suitable choice of healing agents allows a healing optimised for a certain application DCPD with Grubb`s catalyst is not practicable Intolerable smell of the DCPD High price of the catalyst Limited durability of the catalyst

25 Self-healing with the Reflow-Effect 11 Sharp-edged scratches flow to a rounded structure above the T g Increasing of the scratch resistance for furniture coatings, coatings for transparent plastics, parquet floor coatings,.. Coatings and raw materials for the Reflow-Effect for conservation of the aesthetic are commercial available 11

26 Self-healing with retro-diels-alder 12 Reversible polymerization By warming up, disassembling in mono- or oligomers which react while cooling again to the polymer network Healed material retained 60% of its original strength Theoretically the reaction can be repeated infinitely Diene + Dienophile 12 P. Gould; Self-help for ailing structures ; Materials Today June 2003.

27 Self-healing with Diels-Alder 13 Epoxy-coating functionalized with furfuryl glycidyl ether Research of three ways to heal a damage induced by a razor blade: 90 C/2 hours Solvent dimethylformamide (DMF) Solution of bismaleimide in DMF Best results showed the solution of bismaleimide in DMF Future work: encapsulation of the healing agent 13 Purnomo A. Pratama, Amy M. Peterson, Giuseppe R. Palmes, Diffusion and Reaction Phenomena in Solution-Based Healing of Polymer Coatings Using the Diels Alder Reaction Macromolecular Chemistry and Physics 213, 2011,

28 Self-healing Polyurea via modification with Oxetane- Substituted Chitosan 14 Model coating based on hexamethylendiisocyanat (HDI), polyethylene glycole (PEG) and an oxetane substituted chitosan Self-healing by chemical repair; formation of new chemical bonds with the functional groups when activated with UV-light Scratch heals by 30-minutes exposure to UV-light (wavelength of 302 nm, 120 W) 14 Gosh, B.; Urban, M.W., Self-repairing oxetane-substituted chitosan polyurethane networks, Science 232, 2009,

29 Light-induced self-healing of supramolecular polymers 15 Polymers that are linked via metal ions with suitable complex-forming groups [e.g., 2,6 bis(1-methylbenzimidazolyl)pyridin- MEBIP)] Dissolving the non-covalent metal-ligand bondings with exposure of UV-light and following formation of new metal-ligand bondings Possible to heal damaged parts locally hv 15 Burnworth, M, Tang, L; Kumpfer, J.R.; Duncan, A.J.; Beyer, F.J.; Fiore, G.L.; Rowan, S.J.; Weder, C., Optically healable supramolecular polymers, Nature 472, 2011,

30 Possible applications and benefits of self-healing coatings Applications: Heavy duty corrosion protection Wind energy Aerospace technology Areas that are difficult to access Automotive industry Benefits: Decreasing of costs for repair and maintenance Increasing of life-time of investment goods Increasing of safety for human and healthy Preservation of the aesthetic

31 Summary and outlook Self-healing coatings have a great potential for coatings and structures to enlarge the life-time and thus reducing costs or to preserve the aethetic The results of the researches of the IFAM showed the possibilities and the limitations of using filled microcapsules in coatings Suitable self-healing concept has to be chosen depending on the intended use

32 Contact Dipl.-Ing.(FH) Sabine Scharf Paint Technology Fraunhofer Institute for Manufacturing Technology and Advanced Material (IFAM) - Adhesive Bonding Technology and Surfaces - Wiener Straße Bremen Telefon Fax -430 sabine.scharf@ifam.fraunhofer.de