Laboratory exercise

Puu-0.3130

Instrumental analysis in surface, polymer and nanoscience

Lokanathan Arcot

2nd March 2015

Outline

(1) Chronology of the laboratory works

(2) Each step in detail

(3) General issues

(4) Writing the report

Chronology

• Students are divided in groups consisting of two persons• Each group receives one sample

List of samples Chitosan

Xylan (from birch wood)

Cellulose triacetate (DS 3)

Cellulose acetate (DS 2.5)

Carboxymethyl cellulose (DS 0.9)

Carboxymethyl cellulose (DS 1.2)

Pectin

Guar gum

Methyl cellulose

Hydroxyethyl cellulose ethoxyate (quaternized)

Cationic starch (DS 0.75)

Hydroxypropyl cellulose

Sample Analysis

IR (45 min)Raman

(30 min)

Sampleidentification

(meeting)(2h)

NMR(30 min)

Find outa solvent

for your sample(~1 h)

Make a solutionand spin coatultrathin films

(1.5 h)

AFM(morphology/thickness)

(4h)

XPS(chemical analysis)

(2 h)

Sampleidentification

(~4h)

Experimental Exercise ( Total 8 groups)

6 groups with 3 students each; 2 groups of 2 students each )

IR (3rd and 5th March)

Raman (4th March)

Sample Identification (6th March)

Sample dissolution (10,11th of March)

Spin Coating (12,13 of March)

AFM (16,17,18,19,20,24,25,26 March)

XPS

NMR (2,8,9 April)

* QCM-D, SPR (Demo only) (23 and 27 March)

Chronology

Infrared (IR) spectroscopy• Sample form – Powder (KBr pellet preparation)• Samples will be analyzed with photoacoustic IR• Location: PUU 1• Samples must be dry before the measurement (should be placed in the

oven in the IR room)• Contact person (Depending on date)• Meeting place room 234 PUU 1

3rd March timo.paakkonen@aalto.fi and saija.vaisanen@aalto.fi

5th March iina.solala@aalto.fi

Raman spectroscopy

• Sample form – Powder (Direct measurement)• Samples will be analyzed with confocal and UV raman• Time allocated for each group: 15 min• Location: room 303 in PUU2

• Contact person: Leonardo Galvis Rojas (leonardo.galvisrojas@aalto.fi)

Meeting on sample identification

• IR data should be utilized to identify which sample your group has• Search for literature on IR spectra on polysaccharides to compare with

your spectra• A meeting is scheduled where each group presents their spectra and

proposes the identity of their sample (with argumentation)

• Location: PUU1, room 311

• Contact person: Lokanathan Arcot

Dissolution and spin coating• After the identifying the sample, each group must find out what is a

suitable solvent for their sample• Each group must come up with a proposition for a suitable solvent before

entering the exercise dealing with dissolution and spin coating• The sample will be dissolved in a suitable solvent for spin coating• Furthermore, the sample will be dissolved in a deuterated suitable

solvent for NMR analysisTotal 2 solutions – 50 mL 10g/ml normal solvent

200 mg in 1 ml deutrated solvent • Films of four different thicknesses will be cast by spin coating from

solutions of four different concentrations (10, 5, 2.5 and 1 g/l)• Duration: 1h 30 min• Location: room 339 in PUU1• Contact person:

elina.niinivaara@aalto.fi (For Sample dissolution)maija.vuoriluoto@aalto.fi (For Spin coating)

Atomic Force Microscopy (AFM)

• The morphology of spin coated ultrathin films will be characterized with AFM

• The thickness of the ultrathin films will be determined by scratching the sample and measuring the height difference in the scratch with AFM

• Time allocated for each group: 4 hours• Location: PUU1, room 336 (wait outside until escorted inside)

• Contact person: tero.kamarainen@aalto.fi

X-ray Photoelectron Spectroscopy (XPS)

• The chemical nature of the spin coated ultrathin films will be probed with XPS (Used the spin coated sample with 10g/l sample concentration, the same sample used for AFM)

• This is a demonstration: the measurements are so long that you cannot follow them in real time

• The results will be emailed to you shortly after the demonstrations

• Contact person: Leena-Sisko Johansson (leena-sisko.johansson@aalto.fi; phone: 050 555 2608)

• Meeting point – Room 318, PUU 1

Nuclear Magnetic Resonance (NMR)

• The sample dissolved in a suitable deuterated solvent will be analyzed by NMR spectroscopy

• Time allocated for each group: 45 min• Place: Chemistry Department, room D238b

• Contact person: Reeta Salminen (reeta.salminen@aalto.fi; phone: 050 344 1730)

General issues

• Please carry a memory stick throughout the exercises; it is handy for data collection

• If you cannot find a suitable time for your group, please contact the contact person of the relevant exercise

Laboratory report

• Each group hands in a laboratory report• Detailed instructions on how to construct the report will appear shortly in

Noppa

• Deadline for the report: 25th May 2015• Submission through email to Lokanathan Arcot

lokanathan.arcot@aalto.fi• All reports will be automatically checked for plagiarism

What happens now?

(1) Form the groups (three persons each)

(2) Take your samples

(3) Book the times for each exercise

(4) Let’s move to the IR lab to get your samples dehydrated overnight