nanocomposites of cellulose for medical application l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Nanocomposites of Cellulose For Medical Application PowerPoint Presentation
Download Presentation
Nanocomposites of Cellulose For Medical Application

Loading in 2 Seconds...

play fullscreen
1 / 12

Nanocomposites of Cellulose For Medical Application - PowerPoint PPT Presentation


  • 755 Views
  • Uploaded on

Nanocomposites of Cellulose For Medical Application. Asif Rasheed Lecturer, Department of Chemistry University of Wisconsin, Whitewater 800 West Main Street, Whitewater, WI 53190 rasheeda@uww.edu. Cellulose:. The most abundant, biodegradable and biocompatible polymer

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Nanocomposites of Cellulose For Medical Application' - kalea


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
nanocomposites of cellulose for medical application

Nanocomposites of Cellulose For Medical Application

Asif Rasheed

Lecturer, Department of Chemistry

University of Wisconsin, Whitewater

800 West Main Street, Whitewater, WI 53190

rasheeda@uww.edu

cellulose
Cellulose:

The most abundant, biodegradable and biocompatible polymer

Applications include fiber, paper, membrane, polymer and paint industries

Tissue engineering

Nanocomposites

Strong intra and intermolecular hydrogen bonding hence difficult for processing

H - bonding is reduced by partial replacement of hydroxyl groups, this process involves complex multiple steps and uses toxic chemicals => Conern to Environment

Effect on Nano-filler

cellulose dissolution
Cellulose Dissolution
  • Ionic Liquid: Able to break down H-bonding in biopolymers, hence can dissolve biopolymers e.g. cellulose and silk

1-ethyl-3-methylimidazolium acetate (EMI acetate)

Cellulose pulp paper (Grade V-60) from Buckeye Technologies Inc.

Degree of Polymerization ~ 820

Control cellulose film regenerated from ionic liquid

slide4
Composites of cellulose and vapor grown carbon nanofiber (VGCNF) and carbon nanotubes
  • Composites of cellulose and hydroxyapatite (HAP)
slide5

1) Cellulose-CNT Nanocomposite

SWNT

MWNT

VGCNF

  • Young’s Modulus ~ 1 TPa
  • Electrical Conductivity
  • ~ 100 times Stronger than Steel at 1/6th of weight
  • Thermal Conductivity
previous experience with polyacrylonitrile pan vgcnf nanocomposites
Previous Experience with Polyacrylonitrile (PAN)/VGCNF Nanocomposites

Mechanical Properties

Electrical Conductivity

Thermal Stability

Experimental and theoretical specific modulus of various PAN/VGCNF composite films assuming the modulus of VGCNF to be 50 GPa. (a) Experimental modulus, (b) theoretical modulus assuming VGCNF length to be 0.2 m, (c) 1 m, (d) 10 m and (e) 100 m.

Electrical conductivity of PAN/VGCNF composite films.

Tan δ (below) as a function of temperature for (a) Control PAN, (b) PAN/5%VGCNF, (c) PAN/10%VGNCF, (d) PAN/20%VGCNF, (e) PAN/40%VGCNF and (f) PAN/90%VGCNF composite films.

Guo, H.; Rasheed, A.; Kumar, Satish J Mater Sci (2008) 43:4363-4369

slide7

Incorporation of a nano-filler (SWNT, MWNT, VGCNF) into cellulose matrix is expected to

    • Enhance tensile strength and tensile modulus
    • Impart thermal stability
    • Reduce shrinkage (dimensional stability)
    • Result in electrical conductivity in the nanocomposite
  • Electroactive paper
  • Actuators/sensors
  • Medical Devices

Cellulose+5%VGCNF

slide8

2) Cellulose/Hydroxyapatite Nanocomposites

  • Hydroxyapatite (HAP) Ca10(PO4)6(OH)2 finds many applications as bio-material
  • Filler to replace amputated bone
  • Coated to promote bone in-growth into prosthetic implants
  • Cellulose Hydroxyapatite composites have great potential to be used in bone tissue engineering
previous reports cellulose hap composites
Previous Reports: Cellulose/HAP Composites
  • Precipitated on cellulose in-situ from aqueous solution*
  • Deposition of HAP limited to surface
  • The process is extensively long (up to ~14 days) to prepare the composite

Current Approach

  • Homogenous dispersion of HAP in cellulose matrix
  • Fast processing
  • Composition of composite can be easily varied

Cellulose+10% HAP

Cellulose+60% HAP

*Materials Letters 60 (2006) 1710-1713

Hong, L.; Wang Y. L.; Jia, S. R.; Huang, C. G.; Wan, Y. Z. 2005. Hydroxyapatite/bacterial Cellulose Composites Synthesized via Biomimetic Route. Materials Letter. 60:1710-1713

acknowledgments
Acknowledgments
  • Students (Peter Zastraw, Matthew Magruder, Travis Martin)
  • Prof. Peter Jacobs (Geology Department, UW-Whitewater) for XRD
  • UW-Whitewater for funding
  • Department of Chemistry, UW-Whitewater
slide12

Cellulose/HAP Composites: XRD

Testing for biocompatibility