GOHSENOL products can be roughly categorized into two types;
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1) |
those whose acetic groups have all been substituted with hydroxyl groups through saponification (fully saponified type)
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2) |
those whose acetic groups have mostly been substituted with hydroxyl groups through saponification but retain certain portion of acetic groups (partially saponified type).
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The relation between the fully saponified type and partially saponified type can be illustrated as below.
Structural formula
− ( CH2−CH ) m − ( CH2−CH ) n−
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OH [Hydroxyl group] OCOCH3 [Acetic group]
Polymerization degree : m + n
Saponification degree : [m/(m+n)]×100 |
m+n stands for a polymerization degree, while [m/(m+n)]×100 represents a saponification degree. Note that a polymerization degree is usually indicated as a viscosity at a particular concentration (usually, 4 % at 20 degree C)
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| The characteristics of GOHSENOL products are governed by their polymerization degree and saponification degree, as summarized below: |
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Polymerization Degree |
Higher |
Lower |
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Solution viscosity |
Higher |
Lower |
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Membrane strength |
Greater |
Weaker |
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Solubility |
Less water-soluble |
More water-soluble |
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Saponification Degree |
Higher |
Lower |
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Solution viscosity |
Somewhat higher |
Somewhat lower |
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Membrane strength |
Somewhat stronger |
Somewhat weaker |
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Solubility |
Less soluble in cold water |
More soluble in cold water |
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Polymerization and Saponification Degree of GOHSENOL
