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Handbook of Size Exclusion Chromatography and Related ...

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12<br />

<strong>Size</strong> <strong>Exclusion</strong><br />

<strong>Chromatography</strong> <strong>of</strong><br />

Cellulose <strong>and</strong> Cellulose<br />

Derivatives<br />

Elisabeth Sjö holm<br />

Swedish Pulp <strong>and</strong> Paper Research Institute (STFI)<br />

Stockholm, Sweden<br />

1 INTRODUCTION<br />

Cellulose isthe most abundant renewable polymer on Earth, accounting for about<br />

50%<strong>of</strong>theboundcarbon.About10 11 tonsaresynthesizedyearly(1,2),byplants,<br />

algae(forexample,Valonia),someanimals(tunicates),<strong>and</strong>enzymaticallybysome<br />

bacteria (for example, Acetobacter xylinum). Plants are quantitatively the most<br />

important source <strong>of</strong> cellulose. The chemical composition <strong>of</strong> plants depends on<br />

species but alsovaries between individual plants <strong>of</strong> the same species <strong>and</strong> between<br />

different anatomical parts <strong>of</strong> the same plant. Factors that may influence the<br />

chemical composition <strong>of</strong> aparticular plant are, for example, age, place <strong>of</strong> growth,<br />

climate, <strong>and</strong> harvesting time <strong>of</strong> the year. The cellulose content <strong>of</strong> some natural<br />

fiber sources is shown in Table 1. Because there <strong>of</strong>ten is alack <strong>of</strong> information<br />

regarding the sample, sampling, <strong>and</strong> analytical procedure, it is clearly impossible<br />

toreviewabsolutefigures<strong>of</strong>reportedcellulosecontent.Thus,thefiguresshownin<br />

Table 1 should only be regarded as guidelines.<br />

© 2004 by Marcel Dekker, Inc.

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