ISO/TC 45/SC 3/WG 2 - Latex

This document specifies a method for the determination of the high-speed mechanical stability of synthetic rubber latex. The method is not applicable to compounded synthetic rubber latices.

This document provides specifications for natural rubber latex concentrate which has low protein content [low protein natural rubber (LPNR) latex], as follows: — LPNR latex: field latex or concentrated latex pretreated with deproteinising agent, centrifuged and preserved after concentration with ammonia only, with an alkalinity of at least a mass fraction of 0,6 % calculated with respect to the latex. This document is applicable to medical rubber products and avoids the possibility of allergies. This document covers requirements for LPNR latex, type HA (high ammonia), and LPNR latex, type LA (low ammonia).

This document specifies two methods for the determination of the surface tension of polymer dispersions and rubber latices (natural and synthetic). — Method A is the ring method (Du Noüy ring method). — Method B is the plate method (Wilhelmy plate method). Method A is suitable valid for polymer dispersions and rubber latices with a viscosity less than 200 mPa·s. Method B is not suitable for polymer dispersions and rubber latices containing cationic surfactants. Methods A and B are also suitable for prevulcanized latices and compounded material. In case of dispute, the preferred method is method A (the ring method).

This document specifies a method for the determination of the volatile fatty acid number of natural rubber latex concentrate. The method is not necessarily suitable for latices from natural sources other than Hevea brasiliensis and is not applicable to compounded latex, vulcanized latex, artificial dispersions of rubber or synthetic rubber latices.

This document specifies a method for the determination of the alkalinity of natural rubber latex concentrate. The method is not necessarily suitable for latices from natural sources other than Hevea brasiliensis or for synthetic rubber latices, compounded latex, vulcanized latex or artificial dispersions of rubber. NOTE A method for the determination of the alkalinity of polychloroprene latex is specified in ISO 13773.

This document specifies a method for the determination of the KOH number of natural rubber latex concentrate which is preserved wholly or in part with ammonia. The method is applicable to latices containing boric acid. The method is not applicable to latices preserved with potassium hydroxide. It is not necessarily suitable for latices from natural sources other than Hevea brasiliensis, or for latices of synthetic rubber, compounded latex, vulcanized latex or artificial dispersions of rubber.

ISO 20851:2017 specifies the method to examine the presence and approximate count of viable aerobic and facultative anaerobic microorganisms in synthetic rubber latices. Identification of the microorganisms is outside the scope of this document.

ISO 11852:2017 specifies a titration method for the determination of the magnesium content of field natural rubber latex.

ISO 705:2015 specifies a method for the determination of the density of natural rubber latex concentrate between the temperatures of 5 °C and 40 °C. ISO 705:2015 is intended for use when density determinations are used to calculate the mass of a measured volume of latex in locations where it is not practical to weigh directly or to control the temperature of the laboratory.

ISO 19051:2015 specifies a test method for the determination of nitrogen content of raw natural rubber using the Micro Dumas combustion method. This method is also applicable to natural rubber latex.

ISO 2005:2014 specifies a method for the determination of the sludge content of natural rubber latex concentrate. The method is not necessarily suitable for latices from natural sources other than Hevea brasiliensis. It is not suitable for compounded latex or vulcanized latex.

ISO 124:2014 specifies methods for the determination of the total solids content of natural rubber field and concentrated latices and synthetic rubber latex. These methods are not necessarily suitable for latex from natural sources other than the Hevea brasiliensis, for vulcanized latex, for compounded latex, or for artificial dispersions of rubber.

ISO 17403:2014 specifies a cyanide-free titration method for the determination of the magnesium content in field and concentrated natural rubber latex.

ISO 976:2013 specifies a method for the determination of the pH of polymer dispersions and rubber latices (natural and synthetic) by means of a pH-meter equipped with a combined glass and silver reference electrode. The method is also suitable for prevulcanized latex and compounds containing polymer dispersions or rubber latices, including adhesives.

ISO 1652:2011 specifies a method for the determination of the apparent viscosity of both natural rubber latex concentrate and synthetic rubber latices by the Brookfield method. The method is also suitable for the determination of the viscosity of natural latices from sources other than Hevea brasiliensis and also for compounded latices.

ISO 2006-2:2009 specifies a method for the determination of the mechanical stability of synthetic rubber latex. This method measures the mass of coagulum formed when a test portion of latex is stirred for a specified length of time at moderate speed under a relatively high shear stress achieved by applying a load.

ISO 3899:2005 specifies a method for the determination of the residual acrylonitrile content of nitrile rubber latices which have a residual acrylonitrile content of less than 0,2 % (by mass).

ISO 126:2005 specifies a method for the determination of the dry rubber content of natural rubber latex concentrate. The method is not necessarily suitable for latices preserved with potassium hydroxide, latices from natural sources other than Hevea brasiliensis, or for compounded latex, vulcanized latex or artificial dispersions of rubber and it is not applicable to synthetic rubber latices.

ISO 706:2004 specifies a method for the determination of the coagulum content (sieve residue) of natural rubber latex concentrate and the majority of synthetic rubber latices. It is not suitable for XSBR latices intended for use in paper coating.

ISO 35:2004 specifies a method for the determination of the mechanical stability of natural rubber latex concentrate. It is also applicable to prevulcanized natural rubber latex concentrate. The method is not necessarily suitable for latices or prevulcanized latex preserved with potassium hydroxide, latices from natural sources other than Hevea brasiliensis, or for compounded latex or artificial dispersions of rubber, and it is not applicable to synthetic rubber latices.

ISO 12243:2003 specifies a method for the determination of the amount of water-extractable protein in natural rubber (NR) gloves for medical use. The method is potentially suitable for the determination of extractable protein in other articles made from NR latex; however the extraction procedures and times have not been validated and will vary with the type of article to be tested. Other methods for the determination of specific proteins in medical gloves exist (these are described in an annex) but they are not of general applicability. This International Standard is concerned solely with the method of assay. It is not concerned with sampling nor does it purport to address the safety implications of the values obtained or requirements for labelling.

This International Standard specifies procedures for sampling natural rubber latex concentrate and for sampling synthetic rubber latices and artificial latices. It is also suitable for sampling rubber latex contained in drums, tank cars or tanks. The procedures may also be used for sampling plastics dispersions.

Describes the apparatus, the sampling and the procedure.

Describes the principle, the reagents, the apparatus, the procedure, the expression of results and the contents of the test report.

ISO 2004:2017 gives specifications for natural rubber latex concentrate types which are preserved wholly or in part with ammonia and which have been produced by centrifuging or creaming.

ISO 125:2011 specifies a method for the determination of the alkalinity of natural rubber latex concentrate. The method is not necessarily suitable for latices from natural sources other than Hevea brasiliensis or for synthetic rubber latices, compounded latex, vulcanized latex or artificial dispersions of rubber.

ISO 124:2011 specifies methods for the determination of the total solids content of natural rubber latex concentrate and synthetic rubber latices. These methods are not necessarily suitable for latex from natural sources other than the Hevea brasiliensis, for vulcanized latex, for compounded latex or for artificial dispersions of rubber.

ISO 2004:2010 gives specifications for natural rubber latex concentrate types which are preserved wholly or in part with ammonia and which have been produced by centrifuging or creaming.

ISO 2006-1:2009 specifies a method for the determination of the high-speed mechanical stability of synthetic rubber latex. The method is not applicable to compounded synthetic rubber latices.

ISO 124:2008 specifies methods for the determination of the total solids content of natural rubber latex concentrate and synthetic rubber latices. These methods are not necessarily suitable for latex from natural sources other than the Hevea Brasiliensis, for vulcanized latex, for compounded latex or for artificial dispersions of rubber.

ISO 1409:2006 specifies a ring method for the determination of the surface tension of polymer dispersions and rubber latices (natural and synthetic). The method is valid for polymer dispersions and rubber latices with a viscosity less than 200 mPa·s. To achieve this, the dispersion or latex is diluted with water to a mass fraction of total solids of 40 %. If necessary, the solids content is further reduced to ensure that the viscosity is under the specified limit. The method is also suitable for prevulcanized latices and compounded materials.

ISO 1652:2004 specifies a method for the determination of the apparent viscosity of both natural rubber latex concentrate and synthetic rubber latices by the Brookfield method. The method is also suitable for the determination of the viscosity of natural latices from sources other than Hevea brasiliensis and also for compounded latices.

ISO 125:2003 specifies a method for the determination of the alkalinity of natural rubber latex concentrate. The method is not necessarily suitable for latices from natural sources other than Hevea brasiliensis or for synthetic rubber latices, compounded latex, vulcanized latex or artificial dispersions of rubber.

Gives a method for the determination of the pH of polymer dispersions and rubber latices (natural and synthetic) by means of a pH-meter equipped with a combined glass and silver reference electrode. It is also suitable for prevulcanized latex and compounds containing polymer dispersions, including adhesives. Replaces the second edition.

Specifies a macro-method and a semi-micro method for the determination of the nitrogen content in raw natural rubber and in natural rubber latex using variants of the Kjeldahl process. Replaces the second edition.

Specifies a method for the determination of the bound acrylonitrile content of emulsion-polymerized NBR latices. Does also apply to carboxylic-nitrile-butadiene (XNBR) latices and nitrile-isoprene (NIR) latices. Replaces the first edition.

Gives a method for the determination of the dry rubber content of natural rubber latex concentrate. Replaces the third edition which has been insignificantly revised.

Gives a method for the determination of the KOH number of natural rubber latex concentrate which is preserved wholly or in part with ammonia. Applicable to latices containing boric acid, but not applicable to latices preserved with potassium hydroxide. Replaces the second edition which has been technically revised.