Polyme Analysis 2010 Part 13 pdf

-Sample preparation dependent on the physical form of the sample to be analysed.1.. Solids -Nujol mull -Potassium bromide disks -Preparing a solution in a suitable solvent *Nujol Mull -T

Double Bonds

Bending Vibrations

Single Bonds (not to Hydrogen)

Triple Bonds

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FTIR

-The aromatic ring, (C6H5):

+ the group of bands (C-H) above 3010 +a distinctive C=C stretch at about 1600cm-1 -The saturated main chain CH groups: the bands below 3010

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-Sample preparation dependent on the physical form of the sample to be analysed.

1 Solids

-Nujol mull

-Potassium bromide disks

-Preparing a solution in a suitable solvent

*Nujol Mull

-The sample is ground to give a very fine powder

-A small amount is then mixed with nujol → a paste

-Several drops of this paste are then applied between two sodium chloride plates -The plates are then placed in the instrument sample holder ready for scanning

Sample Preparation

FTIR

*Potassium Bromide disk

-A very small amount of the solid (approximately 1-2 mg) is added to pure potassium bromide powder (KBr, ∼ 200 mg) and ground up as fine as possible

-This is then placed in a small die and put under pressure mechanically (several minutes)

-Removing the die and the KBr disk formed The disk is then placed in a sample holder ready for scanning.

Sample Preparation

2 Liquids

-The simplest and most common method of sample preparation

-A drop of the sample is placed between two potassium bromide or sodium chloride circular plates to produce a thin film

-The plates are then placed in a holder ready for analysis

3 Thin Films

-Placing a sample in a suitable holder, such as a card with a slot cut for the

sample window

Sample Preparation

FTIR