Recommended
Recommended
More Related Content
What's hot
What's hot (20)
Similar to Spray Coated Nanocellulose Films Production Characterization and Application
Similar to Spray Coated Nanocellulose Films Production Characterization and Application (20)
More from Kirubanandan Shanmugam
More from Kirubanandan Shanmugam (20)
Recently uploaded
Recently uploaded (20)
Spray Coated Nanocellulose Films Production Characterization and Application
- 1. S.Kirubanandan Ph.D. Student 7th February 2019, Pre Submission Seminar, Department of Chemical Engineering, Monash University SPRAY COATED NANOCELLULOSE FILMS PRODUCTION, CHARACTERIZATION AND APPLICATION Supervisors: Warren Batchelor, Gil Garnier and Christine Browne
- 3. INTRODUCTION Isogai et al. Nanoscale,2011,3, 71-85 3
- 4. APPLICATIONS OF NANOCELLULOSE Packaging1 Oil and water separation2 Photo catalyst3 Gels for Biomedical Applications5 Nanocellulose based composites6 Nanocomposites as High Performance Barrier7 Membrane4 1. K.Shanmugam et al, Cellulose, 2017,24, 7, 2669–2676. 2. Z. he et al, RSC Adv., 2016, 6, 21435-21438 5. Mendoza et al, J Colloid Interface Sci. 2018 1;509:39-46. 7. U.M. Garusinghe et al, Colloids and Surfaces A,540, 2018,233-241. 3. U.M. Garusinghe et al, Scientific Reports, 8, 2306 (2018) 4. V. Swambabu et al , Chemical Engineering Journal 265(1) 2015. 4
- 5. NC FILM PREPARATION TECHNIQUES 1. Casting and Solvent evaporation 2. Vacuum filtration Filtration Separation Drying Processing time – 10 mins – 24 hrs Drying time -10 mins 5 Processing and Drying time – 72 hrs Laboratory scale
- 6. 6 SPRAY COATING 3. Spray coating followed by Vacuum filtration Processing time – 10 – 27 mins Water removal by vacuum Spraying on Fabric surface Beneventi, D., Zeno, E., & Chaussy, D. (2015)
- 7. 7 RESEARCH OBJECTIVE 1. To produce NC film on smooth surface by spraying 2. To tune physical & mechanical properties of NC film with process parameters 3. To reprocess spray coated NC film by recycling 4. To produce nanoclay–nanocellulose into composite by spraying 5. To engineer smoothness of NC film.
- 8. STRUCTURE 8 Applications of Spray Coating Chapter 5 & 6 Process and Sustainability Chapter 3 & 4 Concept Chapter 2
- 9. THESIS STRUCTURE 9 Chapter 1: Introduction and Literature Review Chapter 2: Rapid Preparation of smooth nanocellulose films using spray coating Chapter 3: Flexible Spray Coating Process for Smooth Nanocellulose Film Production Chapter 4: Smooth nanocellulose films as air and water vapour barrier: a sustainable alternative to polyolefin packaging Chapter 5: Spray Coated Nanoclay -Nanocellulose composite as barrier materials Chapter 6: Tailoring surface roughness of Nanocellulose film Chapter 7: Conclusion
- 10. 10 CH 2. RAPID PREPARATION OF NC FILMS Spray system Spray coated NC film A B SS Plate
- 11. 11 Spray system Multiple NC film Impermeable Surface Nanocellulose CH 3. FLEXIBLE SPRAY COATING PROCESS PeelingSpraying
- 12. MECHANICAL PROPERTIES 12 0 10 20 30 40 50 60 70 80 90 100 0 50 100 150 200 250 TensileIndex(Nm/g) Basis weight ( g / m2 ) Series 1 - Concentration effects Series 2 - Conveyor velocity effects Series 3 - Modified Configuration Vacuum Filtration 0 2 4 6 8 10 12 14 16 18 0 50 100 150 200 Young'sModulus(GPa) Basis weight ( g / m2 ) Series 1 - Concentration effects Series 2 - Conveyor velocity effects Series 3 - Modified Configuration Vacuum Filtration
- 13. CHAPTER 3- OUTCOME 13 A flexible spraying process for a strong, dense and robust NC films Increase in uniformity and strength of NC film.
- 14. CH. 4 RECYCLING OF SMOOTH NC FILMS 14 Before Recycling After Recycling Vacuum Filtration
- 15. BARRIER PROPERTIES OF NC FILM 15 Spray coated NC Film < 0.003 µm/Pa.S Recycled sheet (Vaccum Filtration) - 0.0045 µm/Pa.S Air Permanence Water vapour Permeability
- 16. CH 4 -OUTCOME 16 Low permeance of air and water vapour Retained 70% of the tensile strength Recycled NC film shows limited reductions in barrier performance The film was recyclable
- 17. CH 5 .PREPARATION OF NANOCOMPOSITE VIA SPRAYING Nano clay Solution and Nanocellulose Preparation Nanocellulose Nano clay – Nanocellulose (Raw Diacel KY 100S) Composites Nano clay – Nanocellulose (Homogenised 2 passes) Composites Without Homogenization With Homogenization Disintegrator Spray Coating NC- Closite Na++ (MMT) Suspension 2 Pass ˜ 800-1000 Bar 17
- 18. EFFECT OF INORGANICS ADDITION Müller, Kerstin (2017). Nanomaterials. 7. 47. 10.3390/nano7040074.U.M. Garusinghe et al, Colloids and Surfaces A,540, 2018,233-241. 18
- 19. SPRAY COATED NANOCOMPOSITE Closite Na++ ( Natural Bentonite MMT)- Nanocellulose Nanocomposite 20
- 20. EFFECT OF NANO CLAY ADDITION ON WVP ( AFTER HOMOGENIZATION) 20 R² = 0.8283 R² = 0.9988 R² = 0.9975 R² = 0.9772 0 0.5 1 1.5 2 2.5 3 3.5 4 0 5 10 15 20 25 30 35 Watervaporpermeabilityx10-11(g/Pa.s.m) Nanoclay Loading (%) Unhomogenized Composite -Spray coating Unhomogenized composite via Vaccum Filtration Homogenized composite via Vaccum Filtration Homogenized composite via spray coating
- 21. 21 CH 5 . BARRIER MECHANISM
- 22. 22 CH 5 . XRD INVESTIGATIONS 5 10 0 50 100 150 200 IntensityinA.U 2 Theta Degrees Pure MMT Pure Nanocellulose (Homo) 5 Wt.% Composite with Homo 10Wt.% Composite with Homo 20Wt.% Composite with Homo 30Wt.% Composite with Homo
- 23. 23 CH 5 . XRD INVESTIGATIONS 0 5 10 15 20 25 30 0 2 4 6 8 10 12 14 16 Unhomogenized Composite Homogenized CompositeDspacing(A) MMT Loading (%) Pure MMT
- 24. 24 CH 5 . MECHANICAL PROPERTIES 0 5 10 15 20 25 30 0 10 20 30 40 50 60 70 80 90 100 Homogenized Composites Unhomogenized CompositesTensileIndex(Nm/g) MMT Loading (%)
- 25. CH5 . OUTCOME • Low air permeance and water vapour permeability of composites • Composite with good strength 25
- 26. CH. 6 –TUNING SURFACE ROUGHNESS 26 Objective: Tuning surface roughness Super Mirror Stainless Steel Plate Silicon wafersNormal Stainless Steel Plate Different Base surface 17 nm17 nm131 nm333 nm
- 27. 27 APPLICATION OF SMOOTH NC FILMS NC films for printed electronics Smoothness on printing of RFID circuits on NC film Use of nanocellulose in printed electronics: a review (Fanny Hoeng et al., 2016)
- 28. 28 EFFECT OF BASE SURFACE 0 50 100 150 200 250 300 350 400 300 400 500 600 700 800 900 1000 1100 1200 Super Polished SS Square Silicon Wafer Ordinary SS Circular Ordinary SS Square SurfaceRoughnessofNCFilmRa(nm) Surface Roughness of Base Surface Ra (nm) Y = 396.01 +2.05 X R-Square = 0.90
- 29. 29 EFFECT OF FIBRE DIAMETER AND CMC y = 1.9544x + 425.72 R² = 0.9704 y = 0.3478x + 280.14 R² = 0.8748 y = 2.003x + 389.4 R² = 0.9975 y = 2.129x + 328.51 R² = 0.9999 200 300 400 500 600 700 800 900 1000 1100 0 50 100 150 200 250 300 350 SurfaceRoughnessofNC(Rainnm) Roughness of base surface in nm Effect of Raw NC without Homogenization Effect of CMC addition Effect of Homogenization 1 pass Effect of Homogenization 2 Pass
- 30. 30 CH.6 OUTCOME Base/Contact Surface Cellulose Fibres Addition of Polymers
- 31. 31 TIMELINE Chapters in Thesis Expected Time of finishing Chapter 1 : Introduction and Literature Review Jan 2019 (8th Feb 2019) To be reviewed Chapter 2 : Concept Completed and Published Chapter 3 : Full Process Completed and Published Chapter 4 : Sustainability Revised Manuscript submitted Chapter 5 : Application 1 First Draft Completed and Commented Version 3 is ready for review Chapter 6 : Application 2 Drafted rough manuscript in Jan 2019 AFM and SEM data to be incorporated Chapter 7: Conclusion To be written Formatting Thesis 1-2 months
- 32. PUBLICATIONS 32 Shanmugam, K., Varanasi, S., Garnier, G., & Batchelor, W. Rapid preparation of smooth nanocellulose films using spray coating. Cellulose, 24, no 7 (2017) 2669 -2676. (Chapter 2) Shanmugam, K., Hamid Doosthosseini, Swambabu Varanasi, Gil Garnier, and Warren Batchelor. "Flexible spray coating process for smooth nanocellulose film production." Cellulose 25, no. 3 (2018): 1725-1741. (Chapter 3) Kirubanandan Shanmugam, Hamid Doosthosseini, Swambabu Varanasi, Gil Garnier, Warren Batchelor ,” Smooth nanocellulose films as air and water vapour barrier: a sustainable alternative to polyolefin packaging”, Revised Manuscript submitted for Sustainable Materials and Technologies. (Chapter 4) Aysu Onur, Kirubanandan Shanmugam, Aaron Ng, Gil Garnier, Warren Batchelor, “Double layer cellulose fibre- perlite depth filters with cellulose nanofiber top coating for microfiltration and adsorption of positive and negatively charged contaminants”. Manuscript submitted to Cellulose. (Not Included In Thesis) Manuscript Prepared Kirubanandan Shanmugam, Maisha Maliha, Vikram Singh Raghuwanshi, Swambabu Varanasi, Gil Garnier, Warren Batchelor, “ Flexible Process to produce Nanocellulose –Montmorillonite Composite via Spray Coating, Planned to communicate to Composite Science and Technology. (Chapter 5) Kirubanandan Shanmugam, Humayun Nadeem, Christine Browne, Gil Garnier and Warren Batchelor, “Engineering the smoothness of nanocellulose film via spraying”, Planned to communicate to Surface and Coating Technology. (Chapter 6)
- 33. 33 CONFERENCE 1. Kirubanandan Shanmugam, Swambabu Varanasi, Gil Garnier, Warren Batchelor, “Spray Coating – A Rapid Method for Preparation of Free-Standing Nanocellulose Film”, International Conference on Nanotechnology for Renewable Materials 2017, 5 – 8 June 2017, Montreal, Canada. 2. R. Schennach, F. Brumbauer, M. Kräuter, W. Bachelor, K.Shanmugam, C. Czibula, C. Teichert, B. Friedel, “Nano fibrillated cellulose as transparent electrode in an organic solar cell studied by atomic force microscopy” European Materials Research society, 2017 Spring Meeting, 22 to 26 May France. 3. C. Czibula , C. Ganser , M. Kratzer , F. Brumbauer , M. Kräuter , K.Shanmugam , W. Bachelor , M. Penn , M. Ebner , M. Pramstrahler , F. Pilat , T. Chien , R. Schennach , B. Friedel and C. Teichert, “Silver Nanowires: A Verstile Tool For conductive paper” 16th Fundamental Research Symbosium "Advances in Pulp and Paper Research, Oxford 2017, 3 – 8 September 2017, Pembroke College, Oxford, UK. 4. Kirubanandan Shanmugam, Swambabu Varanasi, Gil Garnier, Warren Batchelor, “Tuning Nanoscale Surface Roughness and Smoothness of Nanocellulose Film via Spray Coating” , 2017 ANFF - AMMRF Annual Research Showcase, 22 -23 November 2017 Sydney, Australia. 5. Kirubanandan Shanmugam, Hamid Doosthosseini, Swambabu Varanasi, Gil Garnier, Warren Batchelor, “Recyclability of Spray Coated Smooth Nanocellulose films as a potentially sustainable alternative to synthetic packaging”, International Conference on Nanotechnology for Renewable Materials 2018, 11 – 14 June 2018 Madison, Wisconsin, United States. 6. Humayun Nadeem, Kirubanandan Shanmugam, Swambabu Varanasi, Gil Garnier, Warren Batchelor, “Recycled nanocellulose as a sustainable material: process and barrier performance”, International Sustainable Production and Consumption ICHEME conference, 4 – 5 the October, Manchester, United Kingdom. 33
- 34. ACKNOWLEDGEMENT • Prof. Warren Batchelor and Prof. Gil Garnier, • Dr. Swambabu Varanasi, • Mr. Scot Sharman, • Mrs. Maisha Maliha, • Mr.Hamid Doosthosseini, Graduate Student, MIT, USA. • Mr. Humayun Nadeem, • Student friends and Staff members at BioPRIA, Monash University. 34
- 35. Thank you very much
- 36. PROPERTIES OF NC FILMS 36 0 50 100 150 200 250 300 0 50 100 150 200 250 Thickness(μm) Basis weight ( g / m2 ) Series 1 - Concentration effects Series 2 - Conveyor velocity effects Series 3 - Modified Configuration Vacuum Filtration 600 650 700 750 800 850 900 0 50 100 150 200 ApparentDensity(Kg/m3) Basis weight ( g / m2 ) Series 1 - Concentration effects Series 2 - Conveyor speed effects Series 3 - modified configuration Vacuum Filtration
- 38. Nanocellulose – Potential Barrier • Bio degradable • Non toxic • Extreme High Surface Area • Crystallinity • Tuneable surface for functionalization Martin Hubbe et al, Nano cellulose in Packaging: A Review, Bio Resources 12(1), 2143-2233. 38
- 39. SEM MICROGRAPHS Spray Coated NC film (Homo) Spray Coated 30 % MMT –NC (Homo) Composites Spray Coated 30 % MMT –NC (unhomo) CompositesSpray Coated NC film (unhomo) 39
- 40. Overview of Barrier Materials Aulin and Lindström, Biopolymer Coatings for Paper and Paperboard, John Wiley & Sons, Ltd, 2011, pp. 255-276 40
- 41. 41 EFFECT OF BASE SURFACE 0 100 200 300 400 500 400 600 800 1000 1200 1400 1600 1800 SSS SW OSSC OSSS SurfaceRoughness(RMS)ofNCfilm(nm) Surface Roughness (RMS) of Base Surface (nm) Y = 517.8 +2.38 X R square = 0.91
- 42. 42 y = 0.53x + 330.99 R² = 0.9981 y = 2.4284x + 529.46 R² = 0.9992 y = 2.6511x + 435.08 R² = 0.9995 y = 2.4475x + 701.94 R² = 0.9636 0 200 400 600 800 1000 1200 1400 1600 0 50 100 150 200 250 300 350 SurfaceSmoothenessofNC(Rq(RMS)innm) Roughness of base surface in nm Effect of CMC addition Effect of 1st Pass Homogenization Effect of 2nd Pass Homogenization Effect of Raw NC
Editor's Notes
- Good Morning everyone, Thanks for attending my pre submission seminar presentation on developing nanocellulose films via spray coating Thanks Prof Warren for introducing me to Audience , I am working on the research topic on nanocellulose film and its materials and developing these materials using spray coating, an alternative for vacuum filtration. composites as high performance barrier I would like to summeraize my research work duering my PhD jOURNERY in this presentation
- In technical seminor, I would like to talk about Spray coating concept to make NC film and its full process and its applications I would explain the each chapters of my thesis Conclusion of this research work I have previously presented the development of nanocellulose film via spray coating and its barrier performance and compared with the sheet prepared from vaccum filtration. I need to high light the performance of spray coating The spraying of nanocellulose on the polished metal surface to create a unique surface such as rough surface on the atmosphere side and smooth surface on the metal side The operation time for sheet formation is less than 1 min and comparable uniformity and thickness of the sheet with vaccum filtration The properties of the sheet can be tailored by simple adjusting the suspensison concentration and other process parameters in experimental configuration such as velocity and nozzle type When I see the barrier properties of nanocellusose filme is quite good compared with sheet from vaccum filtration. In this presentation, I had like to talk about the development of nanocellulose based composites via spraying and evaluate its barrier performance and compared with the nanocomposties prepared via vaccum filtration that previously reported.
- Cellulose is the most abundant biopolymer on the earth. Wood fibers are composed of 40–45% cellulose, which is produced in nature via photosynthesis and ubiquitously used in the everyday life.56 The cell wall of natural wood bers has a 3 dimensional (3D) hierarchical structure designed for the metabolic ion transportation and to possess mechanical stability, The microbril bundles are composed of microbril cellulose (MFC) and nanobril cellulose (NFC). MFC is delaminated from wood pulp through mechanical treatments before and/or aer enzymatic or chemical pretreatment, which has a diameter of 5– 60 nm with a length of several micrometers. It has specific characteristics to make many functional sustainable materials Due to its biodegradability, it has good alternative for synthetic polymers It has potential of recyclable It is non –toxic material Due to its biocompatibility, it can be used as base substrate for development of tissue engineering scaffolds It is eco –friendly material
- There are few methods available for nanocellulose films for various functionality. Casting of the nanocellulose suspension is the most common technique at laboratory scale and it requires longest drying time for evaporation of solvent in the suspension. Vacuum filtration is the most method for making the films. It requires processing time from 10 mins to 4 hours in the nanocellulose film and in the case of nanocomposite, it requires 24 hrs s for dewatering in the filtration process
- 3. Spray coating is recently reported to replace the filtration process , however after coating , the same filtration is used to removed the excess water formed sheet and it required time which is not reported in the literature. Therefore, these methods have problem in prepration of nanocellulose film in rapid manner , it requires alternative process for rapid fabrication nanocellulose film
- Based on the research gaps found critical review and analysis of literature, I derive the research objectives for my thesis Spraying of Nc on the impermeable polished metal surface to make NC film Convert into full process and investigate the controlling parameters for tailoring the properties of NC film Recyclability of spray coated NC film and this process offers sustainable pathway. Nancomposite to improve the barrier performance of NC During spraying of NC on the polished metal surface, the part of the surface roughness of metal surface is replicated on the NC film, it might used to engineer the smoothness of the film
- Based on the research objective , I have structure my thesis into three main components, Concept Chapter 2 deals spray coating of NC on metal Full Process – optimising parameters to improve the quality of NC film and connecting with sustainabililty and recylcability Applications – Nancomposite and smooth nc film
- This is the thesis structure in detail. I am going to explain what I have done in completed research and what I am doing in current reseach and explain planned research Based on the research gaps, I have structured thesis into 8 chapters
- The chapter 2 gives rapid method for preparation of nanocellulose film using spray coating. In this method, Spraying of nanocellulose on the polished stainless steel which is on the conveyor at constant velocity and then dried to produce the film with two distinct surface/sids . This work has been reported in cellulose journal. NC film has two distict surface – smooth on metal side and roughness of NC film from this 389 nm The thickness and basis weight of the NC film could ba tailorable with adjucting suspension consistency.
- In this chapter, Full fledged spray process is described and The variables are suspension concentration and effect of velocity on the process and modified configuration. The physical properties and mechanical properties of NC film via spray coating and vacuum filtration investigated The uniformity of the film evaluated via formation test and commented. I would like to brief the process parameters/variables In experimental series 1, the spray jet angle was 50° and the spray width was 30 cm at a spray distance and pressure of 200 bar, respectively. Suspension concentration was kept constant at 1.5 wt.% and conveyor speed was varied from 0.25 cm/s to 0.59 cm/s. 30sec time was allowed for pressure spray system to reach steady state. (Shanmugam et al., 2017) In experimental series 2, the spray system setup was similar to series 1; however, the conveyor speed was kept constant at 0.32cm/s and suspension concentration was varied from 1 wt.% to 2 wt.%. In experimental up series 3, the conveyor system was changed, as was spray nozzle to attain a jet angle of 30° and beam width of 22.5cm at a spray distance of 50.0±1.0 cm and 100 bar pressure. The conveyor speed was kept constant at 1.05 cm/s and suspension concentration varied from 1.5 wt. % to 2.5 wt. %. After spraying, each film was dried on its plate for 24 to 48 hours at ambient conditions, and subsequently removed from the plate and stored at 230C and 50% RH before testing.
- The mechanical properties of the NC film is evaluated thro tensile strength . The tensile Index of the spray coated NC films is a function of Basis weight. Higher basis weight sheets are significantly more rigid. The relationship between the E-modulus and basis weight was found to be linear over the basis weigth range I nvestigated. The strength of spray coated NC film is comparable with the sheet from vaccum filtration. Why strength of spray coated NC is higher than that of vaccum filtration Because of uniformity of the film improved 2. The second effect that may be important is that a denser fibre network will produce a higher number of fibre–fibre bonds, which for films from conventional cellulose fibres from wood has been theoretically and experimentally established to increase elastic modulus due to an improvement in the stress transfer efficiency in the network
- Research Objective: Barrier Potential of Spray Coated Nanocellulose Film and comparison with vacuum filtered nanocellulose film. This work explains barrier potential of nanocellulose such as air permeance and water vapour permeability. Then recyclability potential of the spray coated nanocellulose film and evaluated its barrier performance and strength of the NC films. The most important think is proving the nanocellulose film, an alternate for synthetic packaging materials. Barrier Potential of spray coated NC film Recyclability of Spray coated NC film Proving sustainable packaging material Mechanical Properties of Recycled NC sheet
- The air permeance of the spray coated film is < 0.003 microns/Pa. S a and confirming the low pearmenance of air Similarly, the recycled sheet from spray coated nanocellulose film is 0.0045 microns/Pa.S and confirms the good impermeable for air. Similarly, Water vapour permeability of the NC films and recycled films quite considerable value and compared with synthetic polymers.
- I have attempted to prepared the nanocellulose composite via spray coating. Nanoclay is added with respect to fibre content in suspension and disintegrated at 15000 revoultions and sprayed on the stainless steel at a specified conditions. I have performed experiments with two catagories With homoginization of fibres Without homoginization of Diacel MFC
- Effect of Inorganics Addition in the nanocellulose: In the design of sustainable packaging material , controlling water vapour transmission rate is more critical to extend the shelf life of moisture sentitive foods. To enhance the barrier properties of nanocellulose sheets, inorganic nanomaterials are introducted to the fibre matrix result the formation of nanocomposites . Recently, Uthpala developed nanocomposite with montmorillonite (MMT) and nanocellulose via vaccum filtration and confirmed low water vapour permeabilyt and oxygen transfer rate. The mechnisism of low permeance of water vapour and air is creatiin of tortuous path when MMT arranged orthogonally in fibre matrix and results low op and wvp.
- I have prepared the nanocomposite with three typers of nanoclay Closite Na Closite Ca Closite 116 I have focused only Closite Na and prepared the nanocomposite with homoginzed nanocellulose witj claosie Na++ The nanocellulose –montmorillonite (MMT) compsites were preared via spraying and engineered its barrier performace by varying the MMT loading ( from 5 to 75% of nanoclay into the nanocellulose suspension) All composites are flexible and foldable. For example The composites prepared from clostie Na yellowshed as the MMT conten increased Similarly The composites preared from clostie Ca reddished as the MMT content increased
- After Homoginization of Nanocellulose with nanoclay, WVP decreased for nanocomposite via spraying upto 20% loading and increased due to small aggregation after 30% and values bit higher than that of nanocomposite via vaccum filtration This might be the arrangement of MMT Platelet’s largest dimension perpendicular to the diffusion pathway producing a tortuous path reducting WVP. When comparing with vaccum filtration to make these nanocomposites, the operator time for spray coating less then 1 min and effect of nanoclay loading into the suspesnions is independent of operator time.
- In unhomogenized composites the MMT platelets are exfoliated Homogenized , well randomly distributed
- XRD confirms the structure of nanocomposites via spray coating. NC has no diffraction peak in the 2θ range of 2 to 10°. However, the MMT in the MMT-NC composite showed the peak in this range. The D–spacing of MMT shifted from 11.78 Å to 14.16 Å in the homogenized composites as the MMT content was increased from 5% to 30 wt.%, revealing the formation of intercalated structures of MMT platelets in the cellulose nanofibrils network.
- The shift in
- The spraying is another approach to prepare the smooth nanocellulose films when spraying of NC suspension on different surface. The surface roughness of the film can be optimised by spraying of Nanocellulose on different rough and smooth surface. What controls the surface roughness of the film - Either Base surface and cellulose fibres diameter and its length and its porosity
- The spray coated nanocellulose film is used to print the electronic circuits on the smooth side. Nanocellulose is a sustainable and biodegradable substrate for printing as it has notable printability and flexibility. Especially in printed electronics application, the surface of the substrate should contain minimal surface roughness. The roughness of NC film can be optimized or tailored by spraying NC on different substrates such as stainless steel plate, super mirror stainless steel plate, and silicon wafer, etc. This chapter focuses on the application of smooth nanocellulose film for printing RFID and other printed circuits .
- Homogenization of NC reduce its fibril diamerter resulting in the reduction of roughness of the film Its is high energy consumption process So CMC is added Reduced the roughness of film Silicon wafer cost is high
- I would like to thank my supervisor for guiding this work successfully.
- The properties of NC films are evaluated. it can be seen that there is a linear relation between thickness and basis weight of sheets. This relationship is maintained irrespective of configuration and process parameter changes. The apparent density of the NC film was calculated on the basis weight and the thickness of the NC films. the apparent density as a function of basis weight. It can be seen that for sheets of basis weight around or higher than 100 (g/m2), apparent density is constant. However, for lower basis weights, apparent density is lower demonstrating the effects of agglomerates and surface non-uniformity fibre clumps which become more significant as basis weight is decreased.
- Cellulose based products such as paper and boards are good packaging materials however it is poor barrier properties due to its wide pores Its barrier performance enhanced by coating with wax or laminated with aluminium or plastics , however these coating and extrusion is not recyclable and not biodegradable The challenge is to develop recyclable and sustainable packaging materials
- Nanocellulose is potential barrier material and its minute pores in the web like structure delays and decrease the transfer of water vapour and air The reduction of fibres leaded to reduction of pore size and resulting better barrier properties.
- The figure shows the SEM micrograph on the cross-sectional view of the original composite and composite with high-pressure homogenization with different magnification. The aggregation of MMT as clumps was observed in the interior of the original composites and MMT was aggregated and concentrate on the edges of one part of the original nanocomposites. The average diameter of nanocellulose fibrils before high-pressure homogenization is 70nm with a wide distribution of fibre diameter, a mean length of fibre around 8µm and an average aspect ratio of 142 ± 28 before homogenization. The size of MMT ( nano clay) particles varied from 300 to 1000 nm in length. In original composities, MMT platelets were not intercalated between nanocellulose fibrils due to its large aspect ratio. As a consequence, the spray coated original composites retains an exfoliated structure where MMT platelets are concentred and aggregated on a portion of the composite and not uniformly separated within the cross-section of the composites. In the case of composites with high-pressure homogenization step, MMT platelets are well distributed in the interior nanocomposites and MMT platelets were intercalated uniformly in between the cellulose nanofibrils. The SEM micrographs reveal the MMT platelets equally entangled between cellulose nanofibrils. The average diameter of nanocellulose after high-pressure homogenization is xxx , aspect ratio of homogenized nanocellulose is Due to the reduction of nanocellulose fibres via high-pressure homogenization, cellulose nanofibrils are easily penetrated into MMT platelets layers resulting nanocomposite with an intercalated structure.
- This graph concludes nanocellulose has good oxygen barrier and poor water vapour due to its hydrophilicity Due to high polarity of nanocellulose, water vapour affects the fibre –fibre bonds. Also this material characteristic weakens the original strong bonds holding the dry 2D structure, decreasing water permeability and deterioarating material stability The water vapour permeability of nanocellulose should be improved and to bring to synthetic polymer range.