SIST EN 1890:2006

Surface active agents - Determination of cloud point of non-ionic surface active agents obtained by condensation of ethylene oxide

This document specifies methods for the determination of the cloud point of solutions of non-ionic surface active agents obtained by the reaction of ethylene oxide with a hydrophobic base molecule.
This document primarily applies to surfactants obtained by reaction of ethylene oxide with hydrophobic base molecules, such as fatty alcohols, fatty acids, long-chain alkylphenols, fatty amines, fatty acid esters of sugar derivatives among other ethoxylated non-ionic surfactants, which are by far the most commonly used.
NOTE   Other non-ionic surfactants containing other structural units, such as propylene oxide-ethylene oxide block copolymers, have distinctive behaviours that make the determination of the cloud point more difficult. This leads sometimes to a gradual turbidity over a temperature range of several degrees or even to the occurrence of two cloud points at significantly different temperatures.

Grenzflächenaktive Stoffe - Bestimmung des Trübungspunktes nichtionischer, durch Anlagerung von Ethylenoxid hergestellter grenzflächenaktive Stoffe

Dieses Dokument legt Verfahren zur Bestimmung des Trübungspunktes von Lösungen nicht ionischer
grenzflächenaktiver Stoffe fest, wie sie durch Reaktion von Ethylenoxid mit einem hydrophoben
Ausgangsmolekül erhalten werden.
Dieses Dokument gilt hauptsächlich für grenzflächenaktive Stoffe, wie sie durch Reaktion von Ethylenoxid mit
hydrophoben Ausgangsmolekülen, wie Fettalkoholen, Fettsäuren, langkettigen Alkylphenolen, Fettaminen,
Fettsäureestern von Zuckerderivaten neben anderen ethoxylierten nicht ionischen grenzflächenaktiven
Stoffen erhalten werden, wobei die oben aufgezählten bei weitem am meisten verwendet werden.
ANMERKUNG Andere nicht ionische grenzflächenaktive Stoffe mit anderen strukturellen Einheiten, wie Propylenoxid-
Ethylenoxid-Blockcopolymere, zeigen ein bestimmtes Verhalten, das die Bestimmung des Trübungspunktes schwieriger
macht. Dies führt manchmal zu einer allmählichen Eintrübung über einen Temperaturbereich von mehreren Grad oder
sogar zu zwei Trübungspunkten bei deutlich verschiedenen Temperaturen.

Agents de surface - Détermination du point de trouble des agents de surface non ioniques obtenus par condensation d'oxydes d'éthylene

Le présent document spécifie les méthodes de détermination du point de trouble des solutions d'agents de
surface non ioniques obtenus par réaction de l'oxyde d'éthylène avec un radical hydrophobe.
Le présent document s’applique avant tout aux agents de surface obtenus par réaction de l'oxyde d'éthylène
avec des radicaux hydrophobes, tels que les alcools gras, les acides gras, les alkylphénols à chaîne longue,
les amines grasses, les esters d'acides gras des dérivés du sucre entre autres agents de surface non
ioniques éthoxylés, qui sont de loin les plus couramment utilisés.
NOTE Les agents de surface non ioniques qui contiennent d'autres motifs structuraux, tels que les copolymères
séquencés oxyde de propylène-oxyde d'éthylène, présentent des comportements différents qui rendent plus difficile la
détermination du point de trouble. Ceci se traduit parfois par une turbidité continue sur une plage de températures de
plusieurs degrés ou même par l'apparition de deux points de trouble à des températures significativement différentes.

Površinsko aktivne snovi – Ugotavljanje točke zmotnitve neionskih površinsko aktivnih snovi, pridobljenih s kondenzacijo etilen oksida

General Information

• Status: Published
• Publication Date: 31-Aug-2006
• ICS: 71.100.40 - Surface active agents
• Technical Committee: KDS - Cosmetics, chemical disinfectants and surface active agents
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Sep-2006
• Due Date: 01-Sep-2006
• Completion Date: 01-Sep-2006
• Ref Project: EN 1890:2006 - Surface active agents - Determination of cloud point of non-ionic surface active agents obtained by condensation of ethylene oxide

Relations

• Replaces: SIST EN 1890:1999 - Surface active agents - Determination of cloud point of non-ionic surface active agents obtained by condensation of ethylene oxide
• Effective Date: 01-Sep-2006

Overview

SIST EN 1890:2006 is a European Standard developed by CEN that specifies the standardized methods for determining the cloud point of non-ionic surface active agents (surfactants) produced by the condensation of ethylene oxide with hydrophobic base molecules. The cloud point is a critical temperature at which the aqueous solution of these surfactants turns turbid due to phase separation and then clarifies again upon cooling.

This standard applies primarily to a wide range of ethoxylated non-ionic surfactants, including those derived from fatty alcohols, fatty acids, long-chain alkylphenols, fatty amines, and sugar derivative esters. Accurate determination of the cloud point is essential in the chemical industry for quality control and to understand surfactant performance under different temperature conditions.

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Key Topics

Cloud Point Definition

• The cloud point is the temperature at which a surfactant solution becomes cloudy due to separation into two liquid phases.
• It is sensitive to factors such as ethylene oxide content, surfactant concentration, and presence of additives like electrolytes.
• The temperature at which the solution clarifies on cooling is also monitored and considered as the cloud point for practical purposes.

Test Principle

• The surfactant solution is heated until turbid, then slowly cooled under stirring.
• The temperature at which turbidity disappears marks the cloud point.

Test Methods

SIST EN 1890:2006 describes five distinct methods (A-E) depending on the cloud point temperature and the sample matrix:

• Method A: Pure aqueous solution (1 g sample + 100 g water), for cloud points between 10°C and 90°C.
• Method B: Sodium chloride 50 g/L solution for higher cloud points >90°C.
• Method C: Sodium chloride 100 g/L solution for even higher cloud points >90°C.
• Method D & E: Solutions using diethylene glycol mono-n-butylether (butyldiglycol) for cloud points below 10°C, with different solvent-to-sample ratios.

Precision and Reproducibility

• Repeatability between measurements by the same operator should not exceed 0.5°C difference.
• Reproducibility between different laboratories should not exceed 1°C difference.

Reporting Requirements

The test reports must include:

• Complete identification of the surfactant sample.
• The specific method used (A to E).
• Cloud point results with arithmetic mean and individual values.
• Concentration details if different from standard.
• Date and any deviations from the procedure.

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Applications

• Quality Control in Surfactant Manufacturing: Ensuring product consistency by monitoring cloud point reflects ethoxylation degree and purity.
• Formulation Optimization: Knowledge of cloud point helps formulators predict temperature-dependent behavior of detergents, emulsifiers, and other surface active agents in cosmetics, pharmaceuticals, and industrial cleaners.
• Process Design and Stability Assessment: Cloud point data guide storage and processing temperature limits preventing phase separation or performance loss.
• Environmental and Safety Regulations: Understanding surfactant properties under thermal conditions aids compliance with handling and disposal standards.

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Related Standards

• EN ISO 862:1995 – Vocabulary of surface active agents, providing important definitions related to surfactants.
• EN ISO 3696 – Specification for water purity necessary for laboratory analyses under this standard.
• ISO 607 – Methods for sample division of surface active agents contributing to proper sample preparation.
• ISO 1065 – Another reference for cloud point determination of ethoxylated non-ionic surfactants, supplementing EN 1890 methodologies.

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Keywords: SIST EN 1890:2006, cloud point determination, ethoxylated non-ionic surfactants, surface active agents, surfactant testing methods, ethylene oxide condensation, non-ionic surfactants, butyldiglycol solution, sodium chloride solution, surfactant quality control, CEN standards.

Standards Content (Sample)

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Surface active agents - Determination of cloud point of non-ionic surface active agents obtained by condensation of ethylene oxideAgents de surface - Détermination du point de trouble des agents de surface non ioniques obtenus par condensation d'oxydes d'éthyleneGrenzflächenaktive Stoffe - Bestimmung des Trübungspunktes nichtionischer, durch Anlagerung von Ethylenoxid hergestellter grenzflächenaktive StoffeTa slovenski standard je istoveten z:EN 1890:2006SIST EN 1890:2006en71.100.40ICS:SIST EN 1890:19991DGRPHãþDSLOVENSKI
STANDARDSIST EN 1890:200601-september-2006

EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 1890June 2006ICS 71.100.40Supersedes EN 1890:1999
English VersionSurface active agents - Determination of cloud point of non-ionicsurface active agents obtained by condensation of ethyleneoxideAgents de surface - Détermination du point de trouble desagents de surface non ioniques obtenus par condensationd'oxydes d'éthylèneGrenzflächenaktive Stoffe - Bestimmung desTrübungspunktes nichtionischer, durch Anlagerung vonEthylenoxid hergestellter grenzflächenaktive StoffeThis European Standard was approved by CEN on 18 May 2006.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the Central Secretariat or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2006 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 1890:2006: E

4 Introduction Solutions of non-ionic surface active agents obtained by the reaction of ethylene oxide with a hydrophobic base molecule, in water or in mixtures of water and organic solvents become turbid at a given temperature as the temperature increases and finally separate into two liquid phases. The process is reversible and the system becomes homogeneous again upon cooling. The temperature at which the solution becomes clear upon cooling is determined as the "cloud point". This temperature is characteristic for a particular surfactant. This temperature increases with the amount of ethylene oxide chemically combined in the surfactant molecule for a given composition of solvents. This phenomenon is not limited to ethoxylated surfactants and the cloud point can be determined also for other non-ionic compounds. The knowledge of the cloud point of non-ionic surfactants obtained by the reaction of ethylene oxide with hydrophobic bases is important for their use. For a given base molecule, the cloud point is indeed a simple measure of the amount of the combined ethylene oxide. Moreover, the cloud point suggests directly the temperature at which many functional surfactant properties change dramatically. The curve of cloud point versus degree of ethoxylation is asymptotic; therefore molecules containing high amounts of ethylene oxide show only small differences in their cloud point. In these cases the cloud point loses its significance.

3 Terms and Definitions For the purposes of this document, the terms and definitions given in EN ISO 862:1995 and the following apply. 3.1 cloud temperature temperature above which aqueous solutions of certain non-ionic surface active agents become heterogeneous by the separation into two liquid phases (coacervation) [EN ISO 862:1995] NOTE 1 The value of the cloud temperature depends on the concentration of the solution. NOTE 2 The temperature at which the system become
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