Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Introducing natural nanomaterials - Kristina Oksman


Published on

Tonal Innovation Center (TONIC) hosted the second annual International Musical Instruments Seminar in Joensuu, Finland on 14th September- 16th September 2011.

Published in: Education, Business, Lifestyle
  • Be the first to comment

Introducing natural nanomaterials - Kristina Oksman

  1. 1. IntroductiontoNaturalNanomaterials<br /> Kristiina Oksman Niska<br /> Wood and Bionanocomposites<br />Composite Center Sweden<br /> Luleå University of Technology<br />The 2nd International Musical Instruments Seminar, <br />14-16 September 2011, Joensuu, Finland<br />
  2. 2. Outline<br /><ul><li>Introduction
  3. 3. Nanomaterials from biomass
  4. 4. Separation processes
  5. 5. Properties
  6. 6. Preparation of nanocomposites
  7. 7. Examples of nanocomposites and other nanomaterials based on cellulose
  8. 8. Conclusions</li></li></ul><li>Nanocelluloses and nanocomposites<br /> Nanocellulosic materials<br />Nanofibers/fibrils<br />Nanocrystals/whiskers<br /><100 nm in one dimension<br /> Nanocomposites<br />Polymer where the nano-sized cellulose is used to improve the properties<br />
  9. 9. Research on nanocellulose materials and composites: 1995-2011 ( ISI Web ofSci. Sept 2011)<br />Yano et al, Kyoto, Japan, <br />Zimmermann et al EMPA, Switzerland<br />Oksman et al NTNU, Norway<br />Simonsen et al, Oregon, USA<br />Sain et al, UofT, Canada<br />Glasser, Virginia Tech, USA<br />Winter et al, Suracuse, USA<br />Nanocrystals and composites<br />Taniguchi and Okamora, Niigata, Japan<br />MicrofibrillatedCellulose<br />Cavaille et al Grenoble, France<br />Nanocrystals & composites<br />
  10. 10. Activitiestoday<br />Research interestsarefocussed on<br /><ul><li>Raw materials sources & separation
  11. 11. Largescale / pilot scaleproductionmethods
  12. 12. Chemicalmodifications
  13. 13. Properties
  14. 14. Composite materials development
  15. 15. Modelling
  16. 16. Assemblingoforganizedstructures
  17. 17. Product design</li></ul>Increasedindustrialinteresttouseagro or forestbasednanomaterials<br />H Yano, Kyoto, Japan<br />Sport goods: With over 50,000 CarrotStixrodssold during 2009, the CarrotStixwasthe best-sellingproduct in itspricecategory (Nanopatents and Innovations March 2010) <br />Cellu Comp, Carrot Stix™ <br /><br />
  18. 18. Hierarchical structure of wood<br />Soft wood fiber, diam 20-30 mm, length 2-5 mm <br />Nanofibers, diam <100 nm, length > mm<br />Crystallites, width < 5 nm, length < 300 nm<br />Mechanical properties increases with decreased size<br />Softwood = E-modulus about 12 GPa and strength 100 MPa <br />Wood nanocrystals = E-modulus about 140 GPa and strength 10000 MPa<br />
  19. 19. Examples of nanofibers and nanocrystals<br />Cellulose nanofibers<br />Cellulose nanocrystals<br />Bacterial cellulose<br />Collagen nanofibrils<br /><ul><li>Cellulose crystals/whiskersoriginate from wood, plants or crops, width ~ 5 nm, length >200 nm depending on the source
  20. 20. Cellulose nanofibers originate from wood, plants, crops or bacteria width below 100 nm, length up to µm scale
  21. 21. Collagen fibrils orginate from animal sources, width 50-500 nm length up to mm scale</li></li></ul><li>Nanosize?<br />Nanometer scale<br />1 m<br />Kristiina ~1,550,000,000 nm<br />Ants ~ 6,000,000 nm<br />1 mm<br />Width of a strand of hair ~ 100,000 nm<br />Blood cells ~ 6,000 nm<br />1 μm<br />Bacteria ~1,000 nm<br />Water molecule < 1 nm<br />1 nm<br />gettyimages®/ /<br />
  22. 22. Separationofnanocelluloses:Nanofibers and nanocrystals<br />Mechanical treatments<br /><ul><li>Ultra fine grinding
  23. 23. High pressure homogenizing
  24. 24. Ultra sonication
  25. 25. Cryo crushing</li></ul>Chemical treatments<br /><ul><li>Acid hydrolysis
  26. 26. Enzymatic treatment</li></li></ul><li>Mechanical vs chemicaltreatment<br />Cellulose nanofibers from saw dust<br />Highly coiled and entangled fibers: Ø 10-20 nm, L microns <br />Straight and rigid units: Ø 1.5-3 nm, L microns <br />
  27. 27. Mechanicalseparationofnanofibers<br />Wood<br />Purification<br />Bleaching<br />(Chlorite )<br /> Cellulose<br />Isolation process<br />Soaking in water and mixing<br />Pretreaments<br />(Tempo, Enzymes)<br />Fiber suspension<br />Repeated until gel formation<br />Refining (grinding)<br />Nanofiber suspension<br />
  28. 28. Barley straw<br />Oat straw<br />Grass straw<br />Carrot residue<br />Cellulose<br />Nanofibers from biobased resources<br />
  29. 29. Sample preparation for Electron Microscopy<br />Ethanol<br />Methanol<br /><ul><li>Dried fibers from water
  30. 30. No coating
  31. 31. Solvent exchange
  32. 32. Drying
  33. 33. Coating with gold </li></ul>500 nm<br />500 nm<br />
  34. 34. Nanopaper preparation<br />CNF dispersed in water <br />Vacuum filtration<br />Hot pressing<br />
  35. 35. Mechanical properties of the nanofiber networks<br />Nanofiberpapersprepared by vacuum filtration and pressing<br />14<br /><ul><li>Wood, sludge and carrotnanopapershavesimilarproperties
  36. 36. Reducedfiber size betternetwork  bettermech. prop</li></li></ul><li>amorphous cellulose<br />crystalline cellulose<br />Isolation of cellulose nanocrystals/whiskers<br /> Acid hydrolysis with HCL or H2SO4<br />20 m<br />200 nm<br />MCC <br />Cellulose whiskers<br />10 – 15 m<br />2.<br />HCL or H2SO4<br />3.<br />Heating<br />1.<br />H2O<br />+<br />MCC<br />6.<br />Sonication<br />4.<br />Centrifugation<br />5.<br />Dialysis<br />D. Bondeson, A. Mathew, K. Oksman, Cellulose, 13 (2), 2006, 171-180<br />
  37. 37. Characterizationofcrystals<br />100 nm<br />Length: < 300 nm<br />Width: < 10 nm<br />AFM<br />Flow birefringence between polarized filters<br />
  38. 38. MCC<br />Amorphous regions<br />Crystalline regions<br />Microcrystalline cellulose: crystalline and amorphous regions<br /> Crystals/whiskers have highcrystallinity<br />Elementary fibrils<br />XRD before and afterseparation<br />
  39. 39. Dimensions measurementusing AFM<br />Sample preparation<br />1 μm<br />1 μm<br />Height image<br />Amplitude image<br />62.2 nm<br />40.8 mV<br />Tip broadening effect<br />1 μm<br />
  40. 40. Cellulosenanocrystals from bioresidues<br />Largescaleproductionofcellulose nanocrystals? <br />Wehavefoundthat lignin residue from bioethanolproduction has a highcellulosecontent<br />Thiscellulosecan be separatedto nanocrystals usingonlymechanicalprocessing<br />Oksman et al, Biomass and Bioenergy35(2011)146-152<br />
  41. 41. Cellulose basednanocomposites<br />Cellulose nanofibers or crystals as reinforcements or additives in polymers<br />Interesting properties<br /><ul><li>High mechanical properties
  42. 42. High thermal stability
  43. 43. Large surface area
  44. 44. Bio-compatible
  45. 45. Light weight
  46. 46. Optically transparent
  47. 47. High water binding capacity</li></li></ul><li>Nanocomposites and theirprocessing<br />Films/ sheets<br /><ul><li>Solvent casting
  48. 48. For nanofibers and crystals
  49. 49. Polymer is dissolved in a solvent, nanocellulosesareadded and the solvent is evaporated
  50. 50. Usuallywatersoluble polymers areused</li></ul>Thermosetcomposites<br /><ul><li>Nanopapersheetsareimpregnatedwiththermosetresin
  51. 51. Highnanofibercontent
  52. 52. Goodmechanicalproperties</li></li></ul><li>Feeding<br />Heating and Mixing<br />Motor<br />+<br />Freeze drying and granulation<br />Melt compounding<br /><ul><li>Nanocellulose fibers and crystals, thermplastic matrix
  53. 53. Content is low < 5%
  54. 54. Industrial process
  55. 55. Possibletoinjectionmould</li></ul>Feeding of nanocrystals/fibers in to the extruder is a challenge<br />Liquid feeding<br /><ul><li>Fibers/crystalsaredispersed in a liquid
  56. 56. Removalliquid
  57. 57. Degradationthe polymer</li></ul>Dry feeding<br /><ul><li>Masterbachwithhighnanocellulosecontent
  58. 58. Dilutedduringextrusion</li></li></ul><li>Other possibilities to use nanocellulose<br />Continuous nanofibers<br />Electrospinning of nanofibers<br />Aligned cellulose fibers<br />Reinforced with nanocrystals<br />Improve fiber properties<br />Coatings<br /><ul><li>Use nanocellulose to improve adhesion between fibers and resin
  59. 59. Improve mechanical properties of the laminate, paper etc
  60. 60. Improve barrier properties</li></li></ul><li>Electrospinning of nanofibers<br />Several nanofibers are spun and collected on the collector<br />Polymer nanofibers<br />
  61. 61. More possibilities<br />Aerogels, extremly lightweight materials<br /><ul><li>Aerogels are solid materials with a density as low as 2 mg/cm3
  62. 62. Both whiskers and nanofibers</li></ul>Freeze and supercritical CO2 drying<br />Cranston E and Gray D, <br />Biomacromolecules 7 (2006) 2522<br />Colored thin films <br /><ul><li>Nanowhiskers
  63. 63. Self-assembling
  64. 64. Surface structure</li></ul>Araki J; Wada M; KugaS; Okano T. Langmuir 2000, 16, 2413<br />
  65. 65. Cellulose nanocomposites for medical use<br />LTU Dr. AP Mathew (TEM-PLANT EU-project)<br />Composites with cellulose nanofibers (Domsjö cellulose)<br /><ul><li>Strength 28-40 MPaandstrain20-30% at bodytemperature and highmoistureconditions*
  66. 66. Biocompatible</li></ul>*Santis de R, et al. Comp SciTechnol 2004;64:861-871<br />
  67. 67. Mechanical properties of cellulose-collagen nanocomposites for ligament application<br />Effect of simulated body conditions and sterilization<br />
  68. 68. Prototypes<br />BraidedXColl-Cell <br />NFPDTubules<br />Braided NFPD<br />Stable in PBS medium (phosphate buffered saline)<br />
  69. 69. Possible applications<br />High-strength spun fibers and textiles<br />Advanced composite materials<br />Films for barrier and other properties<br />Additives for coatings, paints, lacquers and adhesives<br />Optical devices<br />Electronic applications, lightweightbatteries<br />Pharmaceuticals and drug delivery <br />Bone and ligament replacements<br />Hydrogels<br />Aerogels<br />Improved paper, packaging applications<br />New building products<br />Additives for food and cosmetics<br />Separation membranes<br />
  70. 70. Some conclusions<br />Increased interest for natural and renewable nanomaterials<br />Bio based residues can be used for separation of natural nanomaterials<br />Nanomaterials are separated to nanosize using chemical/mechanical processing<br />Nanocomposites processing methods are casting, impregnation, compounding, spinning, freeze and supercritical CO2 drying<br />Nanomaterials can be used in medical applications, aerogels, nanomembranescoatings, textiles, composites, packakingappl. etc.<br />
  71. 71. Thank you for listening…<br />Thank my research team for all results and hard work<br />
  72. 72. Yield of the separation process of nanocelluloses<br />Cellulosecontent and yieldwashighest for lignin residuefollowed by oatstraw > carrotresidue > barleystraw > grassstraw<br />