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CELLULOSE/POLYSULFONE NANOCOMPOSITES

Sweda Noorani and John Simonsen

Oregon State UniversityCorvallis, Oregon

CONTENTS

Background– Membranes– MECS

Experimental methodsResults Conclusions Acknowledgements

Membranes

Membrane Technology and Applications, R.W. Baker, Wiley & Sons, West Sussex, England

Membrane Technology and Applications, R.W. Baker, Wiley & Sons, West Sussex, England

Membrane Technology and Applications, R.W. Baker, Wiley & Sons, West Sussex, England

MECS

Microtechnologies in Energy and Chemical Systems

Materials & Process Design for MECS

Prof. Sundar V. Atre

materialpolymermetal

ceramiccomposite

applicationkidney dialysismicroreactor

thermal managementfuel cell

processinjection molding

extrusionsintering

micromachining

Fluid Collection Cap

Fluid Collection Cap

Diffusion Area

Dialyzer Unit Assembly Schematic

“Blood”

Dialysate

Adjustable Spacer

Quartz Window

Camera Visual Access

Membrane

Prof. Goran Jovanovic, OSU ChE

MECS Dialyzer Design

Hollow Hollow –– fiber filterfiber filter

MECS filterMECS filter

Experimental Methods

Crystalline regions

Amorphous region

Acid hydrolysis

Individual nanocrystals

Individual cellulose polymer

Cellulose Nanocrystal Production

Native cellulose

Polymer film preparation

Solvent exchange to 1-methyl-2-pyrrolidone (NMP)Combine with polysulfone (PSf) in NMPCast films two ways:– Coagulation via Loeb-Sourirajan anisotropic

film– Solvent evaporation

EvaluationMechanical testing –Sintech 1G, Universal testing machine

tensile test modeData converted to stress-strain curves

Thermal AnalysisDifferential Scanning Calorimetry, TA Instruments DSC

2920-Temperature range – 20-250oC- Heating/cooling rate – 10 oC/min

Thermo gravimetric analysis , TA Instruments, Q500- Temperature range – 40-600oC- Heating rate –10oC/min

Evaluation

Scanning electron microscopy (SEM)– AMRay 1000A @ 10 kV– Coated with Au-Pd film (8-10 nm)

Atomic force microscopy (AFM)– DI Dimension 3100 (Veeco Instruments)– Tapping mode

Mechanical properties

Stress-strain

0

20

40

60

80

100

120

140

0 0.02 0.04 0.06 0.08 0.1 0.12 0.14

Strain, mm/mm

Str

ess,

MP

a

0% NCC2% NCC

MOE = 1.1 GPa

MOE = 4.0 GPa

Thermal Properties

180.13°C

167.10°C1.096J/g

-0.8

-0.6

-0.4

-0.2

0.0

0.2

Hea

t Flo

w (W

/g)

0 50 100 150 200 250

Temperature (°C)

Sample: psf film nov 17,04Size: 5.0000 mgMethod: RampComment: PSF FILM

DSCFile: C:...\sweda\psf film nov 17,04(DSC).002Operator: swedaRun Date: 17-Nov-04 15:23Instrument: 2920 MDSC V2.6A

Exo Up Universal V3.3B TA Instruments

Tg of NCC-filled PSf

160

165

170

175

180

185

0 2 4 6 8 10 12 14 16 18

NCC, wt %

Tg

, C

TGA Psf

53.50%(0.5789mg)

40

60

80

100

120

Wei

ght (

%)

0 100 200 300 400 500 600

Temperature (°C)

Sample: psf film nov 17, 04Size: 1.0820 mgMethod: Ramp

TGAFile: C:\Data\sweda\psf film nov 17,04.001Operator: swedaRun Date: 17-Nov-04 15:07Instrument: 2950 TGA HR V6.0E

Universal V3.3B TA Instruments

TGA of NCC in Nitrogen/air

0

20

40

60

80

100

120

0 100 200 300 400 500Temp oC

We

igh

t lo

ss

%

NCC in airNCC

0

2

4

6

8

10

12

20 70 120 170 220 270 320 370 420 470 520 570

Temp

Wei

ght l

oss

rate

(%/m

in)

Pure Cellulose

Cellulose nanocrystal Sulfate groups

decrease onset degradation temperature

Ea=113.53kj/mole

Ea=153.1kj/mole

(oC)

Derivative Thermogravimetric (DTG) Curves

TGA (Psf film with 2% NCC)

49.83%(1.024mg)

40

60

80

100

120

Wei

ght (

%)

0 100 200 300 400 500 600

Temperature (°C)

Sample: psf film (ncc)nov 17, 04Size: 2.0540 mgMethod: Ramp

TGAFile: C:...\sweda\psf film(ncc) nov 17,04.001Operator: swedaRun Date: 17-Nov-04 17:07Instrument: 2950 TGA HR V6.0E

Universal V3.3B TA Instruments

TGA-11% NCC

7.710%(0.1496mg)

48.43%(0.9396mg)

20

40

60

80

100

120

Wei

ght (

%)

0 100 200 300 400 500 600

Temperature (°C)

Sample: sample1_dec 30_tgaSize: 1.9400 mgMethod: Ramp

TGAFile: C:\Data\sweda\sample1_dec30_tga.001Operator: swedaRun Date: 30-Dec-04 10:41Instrument: 2950 TGA HR V6.0E

Universal V3.3B TA Instruments

TGA-16% NCC

11.52%(0.2281mg)

38.88%(0.7699mg)

40

60

80

100

Wei

ght (

%)

0 100 200 300 400 500 600

Temperature (°C)

Sample: sample2_dec 30_tgaSize: 1.9800 mgMethod: Ramp

TGAFile: C:\Data\sweda\sample2_dec30_tga.001Operator: swedaRun Date: 30-Dec-04 12:02Instrument: 2950 TGA HR V6.0E

Universal V3.3B TA Instruments

SEM

AFM images

0% NCC

0% NCC

0% NCC

Rms = 0.184 nm

2% NCC

2% NCC

11% NCC

11% NCC

11% NCC

Rms = 13 nm

11% NCC

11% NCC

11% NCC

12 nm high

11% NCC

184 nm wide

11% NCC, other side of film

11% NCC

Rms = 96 nm

(other side = 13 nm)

11% NCC, light tapping

11% NCC, hard tapping

16% NCC

16% NCC

Rms = 1.9 nm

CONCLUSIONSNCC can be dispersed in PSf– Quality of the dispersion is less than perfect

NCC effects the Tg of the PSf

TGA indicates 2% NCC in PSf behaves differently, close

association?

NCC stiffens, but does not strengthen composite

– Interphase needs improvement

Hard tapping on AFM has promise as technique to visualize

Loadings of 16% cause dry out, poor properties

ACKNOWLEDGEMENTS

This project was supported by the National Research Initiative of the USDA Cooperative State Research, Education and Extension Service, grant number 2003-35103-13711

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