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Handbook of Size Exclusion Chromatography and Related ...

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Table 2 Various Solvents <strong>and</strong> Operating Temperatures in the Literature for SEC Analysis<br />

<strong>of</strong> Rubbers a<br />

Polymer Solvent Temperature (8C) References<br />

EPDM TCB 135 70<br />

THF 39<br />

EVA (high VA) THF Ambient 70<br />

EVA (low VA) ODCB 140 70<br />

NR Toluene 80 70<br />

THF 24 5<br />

THF 27 6<br />

THF 35 7,9<br />

THF 40 3<br />

THF 10<br />

Polyacrylonitrile DMF 80 70<br />

Polybut-1-ene TCB 140 70<br />

BR Toluene 80 70<br />

THF 40 29<br />

THF 22,24,28<br />

Q Toluene 80 70<br />

THF Ambient 70<br />

Polyurethane THF Ambient 70<br />

DMF 80 70<br />

SBR Toluene 80 70<br />

THF 40 21<br />

THF 20<br />

IR THF Ambient 58<br />

Toluene 80 70<br />

Z THF 30 30<br />

Acetone þ cyclohexane 31<br />

a EVA, polyethylene þ vinyl acetate; TCB, 1,2,4-trichlorobenzene; ODCB, 1,2-dichlorobenzene.<br />

crosslinking when h<strong>and</strong>ling rubbers. The most common example is seen in<br />

unmilled natural rubbers. When such a component is present, SEC analysis affords<br />

only the molecular weight data on the soluble fraction, excepting the gel fraction.<br />

In this case, to underst<strong>and</strong> the viscoelastic properties <strong>of</strong> the rubbers connected with<br />

the SEC data is not appropriate because the gel contributes to these properties.<br />

Studies <strong>of</strong> the influence <strong>of</strong> the gel fraction on the mechanical properties <strong>of</strong> natural<br />

rubber are listed in a relevant article (61). The suggestion is that, in natural rubber,<br />

the gel tends to be soluble in SEC solvents when suitably masticated.<br />

A common practice in SEC is to filter the sample solution through<br />

an approximately 0.5mm filter used for the injection. This means that the gel<br />

© 2004 by Marcel Dekker, Inc.

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