ISO 4320:1977 pdf download.Non-ionic surface active agents — Determination of cloud point index — Volumetric method.
INTRODUCTION
Determination of the cloud point index provides a way of characterizing weakly alkoxylated derivatives and their hydrocarbon hydrophobic groups.
This simple and rapid measurement is a valuable means for checking the level of alkoxylation of non-ionic derivatives Intended, for example, for suiphonation.
1 SCOPE
This International Standard specifies a volumetric method for the determination of the cloud point index of non-ionic surface active agents.
The method is applicable to weakly alkoxylated non-ionic surface active agents (1 to 5 oxyethylene groups) the hydrophobic group of which is provided by an alcohol, an alkyiphenol or a fatty acid (provided that the last has a melting point lower than 30 °C), subject to the product being soluble in propan-1-ol to the extent of 1 g in 10 ml at 30 °C.
It is equally applicable to lipophilic bases derived from alcohols, alkylphenols and fatty acids.
3 REFERENCE
ISO 607, Surface active agents – Detergents — Methods of sample division.1)
4 DEFINITION
For the purposes of this International Standard, the following definition applies :
cloud point index : The number of millilitres of distilled water necessary to render cloudy, at a specified temperature, a solution containing a given mass of surface active agent in a given volume of solvent.
7 APPARATUS
Ordinary laboratory apparatus, and in particular :
7.1 Beaker (see the figure) of height 80 mm and diameter
50 mm, with double walls permitting temperature stability, and having a mass less than 200 g, fitted with a polyethylene, polytetrafluoroethylene or an aluminium foil cover pierced with two holes allowing entry of the thermometer (7.2) and the burette (7.4).
10 EXPRESSION OF RESULTS
10.1 Method of calculation
The cloud point Index of the product is expressed as the volume, in millilitres, of water Introduced to render cloudy 10 ml of a 100 g/l solution of non.ionic surface active agent in propan-1-ol.
Take as the result the mean of at least three determinations, expressed to the nearest 0,05 ml (1 drop of water).
10.2 Repeatability
The maximum difference between the results of two deter• minatlons carried out In rapid succession on the same sample, by the same analyst using the same apparatus, should not exceed 2 % of the mean volume found.ISO 4320:1977 pdf download.