SIST ISO 458-2:1996

Plastics -- Determination of stiffness in torsion of flexible materials -- Part 2: Application to plasticized compounds of homopolymers and copolymers of vinyl chloride

Application of the general method in ISO 458-1 for the above mentioned plastics according to the special case of the method with an angle of deflection between 55 and 65 . The temperatures according to three characteristic values of the torsion stiffness; 300 MPa, 23 MPa and 4 MPa are to be determined for the material under test.

Plastiques -- Détermination de la rigidité en torsion des plastiques souples -- Partie 2: Application aux compositions plastifiées d'homopolymères et de copolymères de chlorure de vinyle

La présente partie de l'ISO 458 spécifie une méthode de détermination des températures correspondant à trois valeurs de la rigidité en torsion caractéristiques conventionnelles, des compositions plastifiées d'homopolymères et de copolymères de chlorure de vinyle.

Polimerni materiali - Določanje torzijske togosti upogljivih materialov - 2. del: Mehčane zmesi homo- in kopolimerov vinilklorida

General Information

• Status: Published
• Publication Date: 31-May-1996
• ICS: 83.080.20 - Thermoplastic materials
• Technical Committee: IPMA - Polimer materials and products
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Jun-1996
• Due Date: 01-Jun-1996
• Completion Date: 01-Jun-1996
• Ref Project: ISO 458-2:1985 - Plastics - Determination of stiffness in torsion of flexible materials - Part 2: Application to plasticized compounds of homopolymers and copolymers of vinyl chloride

Relations

• Revised: ISO/R 458:1965 - Plastics - Determination of stiffness in torsion as a function of temperature
• Effective Date: 12-May-2008

Overview

SIST ISO 458-2:1996 is an international standard developed by the International Organization for Standardization (ISO) that specifies a method for determining the torsional stiffness of flexible plastic materials. This part of the ISO 458 series focuses specifically on plasticized compounds of homopolymers and copolymers of vinyl chloride (PVC). It provides a precise procedure for measuring torsional stiffness over a temperature range, corresponding to key stiffness values relevant for practical applications of flexible PVC materials. The standard complements the general testing methods outlined in ISO 458-1 by addressing the particular behavior of PVC compounds when subjected to torsion.

Key Topics

• Scope and Purpose: Applies ISO 458-1 general procedures to plasticized vinyl chloride homopolymers and copolymers with an angle of deflection between 55° and 65°.
• Characteristic Stiffness Values: The standard identifies three key values of torsion stiffness to be determined:
  • 300 MPa (high stiffness region)
  • 23 MPa (intermediate stiffness)
  • 4 MPa (low stiffness region)
• Temperature Determination: The temperatures at which these stiffness values occur are established to characterize the material’s flexibility and rigidity properties over different thermal conditions.
• Test Specimens: Specifies the use of test specimens with distinct thickness ranges for accurate measurement near each stiffness value:
  • 1.8 to 2 mm
  • 2 to 5 mm
  • 4 to 5 mm
• Testing Procedure: Detailed steps for applying torque and measuring angular deflection to calculate stiffness, followed by plotting torsional stiffness logarithm against temperature to analyze the material’s behavior.
• Application of the Method: Focus on the "S-shaped" curve of stiffness versus temperature common in plasticized PVC materials, defining zones of high stiffness, intermediate transition, and low stiffness for comprehensive analysis.

Applications

SIST ISO 458-2:1996 is critical for manufacturers, quality control laboratories, and researchers working with flexible PVC compounds, particularly when evaluating:

• Material Performance Under Temperature Variations: Understanding how plasticized PVC loses stiffness and gains flexibility at different temperatures aids in product design.
• Flexibility and Durability Analysis: Essential for products such as flexible films, curtains, tablecloths, and waterproof materials where mechanical torsional properties influence usability.
• Standardized Testing for Compliance: Enables consistent and comparable torsional stiffness results across different batches and suppliers.
• Material Development and Optimization: Helps in modifying plasticizer content or polymer blends to achieve desired flexibility properties suited for specific end-use conditions.
• Quality Assurance: Ensures materials meet stiffness requirements critical for manufacturing processes and final product performance.

Related Standards

• ISO 458-1: Plastics - Determination of stiffness in torsion of flexible materials - Part 1: General method
  Provides the foundational testing method on which ISO 458-2 builds its specific application for PVC compounds.

• ISO/R 458-1965
  The previous version of the stiffness determination method, now superseded by ISO 458-1 and ISO 458-2, reflecting updated technical revisions.

• Other ISO Standards on Plastic Testing
  Standards related to mechanical and thermal property evaluation of plastics for comprehensive material characterization.

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Keywords: ISO 458-2, torsion stiffness, plasticized PVC, flexible plastics, homopolymers of vinyl chloride, copolymers of vinyl chloride, plasticized compounds, plastics testing, torsional rigidity, temperature-dependent stiffness, standard test method, ISO plastics standards.

Standards Content (Sample)

SLOVENSKI STANDARD
01-junij-1996
3ROLPHUQLPDWHULDOL'RORþDQMHWRU]LMVNHWRJRVWLXSRJOMLYLKPDWHULDORYGHO
0HKþDQH]PHVLKRPRLQNRSROLPHURYYLQLONORULGD
Plastics -- Determination of stiffness in torsion of flexible materials -- Part 2: Application
to plasticized compounds of homopolymers and copolymers of vinyl chloride
Plastiques -- Détermination de la rigidité en torsion des plastiques souples -- Partie 2:
Application aux compositions plastifiées d'homopolymères et de copolymères de
chlorure de vinyle
Ta slovenski standard je istoveten z: ISO 458-2:1985
ICS:
83.080.20 Plastomeri Thermoplastic materials
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

International Standard 45812
INTERNATIONAL ORGANIZATION FOR STANDARDIZATIONW’.4E~((nYHAPO~l-lAR OPrAHM3AL&lR fl0 CTAH~APTL43A~Mti.ORGANlSATlON INTERNATIONALE DE NORMALISATION
Plastics - Determination of stiffness in torsion of flexible
materials -
Part 2 : Application to plasticized compounds of
homopolymers and copolymers of Vinyl chloride
Plastiques - Determination de Ia rigidit& en torsion des plastiques souples - Partie 2 : Application aux compositions plastifiees
d’homopolymkes et de copolym&es de chlorure de vin yle
First edition - 1985-04-01
UDC 678.743.22 : 620.175.251
Ref. No. ISO 458/2-1985 (E)
Descriptors : plastics, Vinyl chloride, tests, torsion tests, determination, torsion angle, rigidity, test equipment.
Price based on 2 pages
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of
national Standards bodies (ISO member bedies). The work of preparing International
Standards is normally carried out through ISO technical committees. Esch member
body interested in a subject for which a technical committee has been established has
the right to be represented on that committee. International organizations, govern-
mental and non-governmental, in liaison with ISO, also take patt in the work.
Draft International Standards adopted by the technical committees are circulated to
the member bodies for approval before their acceptance as International Standards by
the ISO Council. They are approved in accordance with ISO procedures requiring at
least 75 % approval by the member bodies voting.
International Standard ISO 458/2 was prepared by Technical Committee ISO/TC 61,
Plas tics .
International Standards ISO 458/1 and ISO 458/2 cancel and replace ISO Recommen-
dation R 458-1965, of which they constitute a technical revision.
International Organkation for Standardkation, 1985
Printed in Switzerland
ISO 458/2-1985 (EI
INTERNATIONAL STANDARD
Plastics - Determination of stiffness in torsion sf flexible
materials -
Part 2 : Application to plasticized compounds of
homopolymers and copolymers of Vinyl chloride
0 Introduction 1 Scope and field of application
In the case of compositions based on plasticized polyvinyl
This part of ISO 458 specifies a method for determining the
chloride, all the curves for the logarithm of the stiffness in tor- temperatures
corresponding to three conventional
sion as a function of temperature have a similar appearance, in
characteristic values for the stiffness in torsion of plasticized
the form of a reversed S. Esch curve is essentially characterized
compounds of homopolymers and copolymers of Vinyl
by three regions : chloride.
a) two extreme regions, where the change in the stiffness
2 Reference
as a function of temperature occurs relatively slowly :
ISO 45811, Plastics
- Determination of stiffness in torsion of
1) a region of elevated values, corresponding to a high
flexible ma terials
- Part 7 : General method.
degree of rigidity, attributed by some authors to a loss of
elastic properties. The value of the stiffness in torsion
3 Principle
was taken arbitrarily by Clash and Berg Ill as
3,l x 109 dyn/cm**,
Use of ISO 458/1 for plasticized compounds of homopolymers
and copolymers of Vinyl chloride, consisting of determining, ac-
2) a region of low values, corresponding to a high
...

International Standard 45812
INTERNATIONAL ORGANIZATION FOR STANDARDIZATIONW’.4E~((nYHAPO~l-lAR OPrAHM3AL&lR fl0 CTAH~APTL43A~Mti.ORGANlSATlON INTERNATIONALE DE NORMALISATION
Plastics - Determination of stiffness in torsion of flexible
materials -
Part 2 : Application to plasticized compounds of
homopolymers and copolymers of Vinyl chloride
Plastiques - Determination de Ia rigidit& en torsion des plastiques souples - Partie 2 : Application aux compositions plastifiees
d’homopolymkes et de copolym&es de chlorure de vin yle
First edition - 1985-04-01
UDC 678.743.22 : 620.175.251
Ref. No. ISO 458/2-1985 (E)
Descriptors : plastics, Vinyl chloride, tests, torsion tests, determination, torsion angle, rigidity, test equipment.
Price based on 2 pages
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of
national Standards bodies (ISO member bedies). The work of preparing International
Standards is normally carried out through ISO technical committees. Esch member
body interested in a subject for which a technical committee has been established has
the right to be represented on that committee. International organizations, govern-
mental and non-governmental, in liaison with ISO, also take patt in the work.
Draft International Standards adopted by the technical committees are circulated to
the member bodies for approval before their acceptance as International Standards by
the ISO Council. They are approved in accordance with ISO procedures requiring at
least 75 % approval by the member bodies voting.
International Standard ISO 458/2 was prepared by Technical Committee ISO/TC 61,
Plas tics .
International Standards ISO 458/1 and ISO 458/2 cancel and replace ISO Recommen-
dation R 458-1965, of which they constitute a technical revision.
International Organkation for Standardkation, 1985
Printed in Switzerland
ISO 458/2-1985 (EI
INTERNATIONAL STANDARD
Plastics - Determination of stiffness in torsion sf flexible
materials -
Part 2 : Application to plasticized compounds of
homopolymers and copolymers of Vinyl chloride
0 Introduction 1 Scope and field of application
In the case of compositions based on plasticized polyvinyl
This part of ISO 458 specifies a method for determining the
chloride, all the curves for the logarithm of the stiffness in tor- temperatures
corresponding to three conventional
sion as a function of temperature have a similar appearance, in
characteristic values for the stiffness in torsion of plasticized
the form of a reversed S. Esch curve is essentially characterized
compounds of homopolymers and copolymers of Vinyl
by three regions : chloride.
a) two extreme regions, where the change in the stiffness
2 Reference
as a function of temperature occurs relatively slowly :
ISO 45811, Plastics
- Determination of stiffness in torsion of
1) a region of elevated values, corresponding to a high
flexible ma terials
- Part 7 : General method.
degree of rigidity, attributed by some authors to a loss of
elastic properties. The value of the stiffness in torsion
3 Principle
was taken arbitrarily by Clash and Berg Ill as
3,l x 109 dyn/cm**,
Use of ISO 458/1 for plasticized compounds of homopolymers
and copolymers of Vinyl chloride, consisting of determining, ac-
2) a region of low values, corresponding to a high
cording to a special case of method A with an angle of deflec-
degree of flexibility. In this case the corresponding stiff-
tion between 55’ and 65O, the temperatures corresponding to
ness in torsion has been arbitrarily taken as
three characteristic values of the stiffness in torsion (77, i.e. :
42 kgf/cm*** representing an appropriate value for films
300 MPa, 23 MPa and 4 MPa.
having a sufficient degree of flexibility at normal use
temperature to render them suita
...

Norme internationale 45812
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION.ME>KfiYHAPOfiHAR OPTAHM3ALWlR l-IO CTAH~APTbl3AlJklt4.ORGANISATION INTERNATIONALE DE NORMALlSATtON
D6termination de la rigidit en torsion des
Plastiques -
plastiques souples -
Partie 2 I Application aux compositions plastifiees
d’homopolym&res et de copolym6wes de chlorure de vinyle
Plastics - Determination of stiffness in torsion of flexible materials - Part 2 : Application to plasticized compounds of
homopolymers and copolymers of vinyl chloride
Premiere bdition - 1985-04-01
R6f. n* : IS0 458/2-1985 (F)
iz
CDU 678.743.22 : 620.175251
essai de torsion, dbtermination, angle de torsion, rigidit& materiel d’essai.
Descripteurs : plastique, chlorure de vinyle, essai,
Prix base sur 2 pages
Avant-propos
L’ISO (Organisation inter-r-rationale de normalisation) est une federation mondiale
d’organismes nationaux de normalisation (comites membres de I’ISO). L’elaboration
des Normes internationales est confide aux comites techniques de I’ISO. Chaque
comite membre inter-es& par une etude a le droit de faire partie du comite technique
tree a cet effet. Les organisations internationales, gouvernementales et non gouverne-
mentales, en liaison avec I’ISO, participent egalement aux travaux.
Les projets de Normes internationales adopt& par les comites techniques sont soumis
aux comites membres pour approbation, avant leur acceptation comme Normes inter-
nationales par le Conseil de I’ISO. Les Normes internationales sont approuvees confor-
mement aux procedures de I’ISO qui requierent I’approbation de 75 % au moins des
comites membres votants.
La Norme internationale IS0 458/2 a ete elaboree par le comite technique lSO/TC 61,
Plas tiques.
Les Normes internationales IS0 458/l et IS0 458/2 annulent et remplacent la Recom-
mandation ISO/R 458-1965, dont elles constituent une revision technique.
Organisation internationale de normalisation, 1985
Imprimi! en Suisse
IS0 458/2-1985 (F)
NORME INTERNATIONALE
DGtermination de la rigidit en torsion des
Plastiques -
plastiques souples -
Partie 2 I Application aux compositions plastifi6es
d’homopolym&es et de copolym&res de chlorure de vinyle
0 Introduction
1 Objet et domaine d’application
Dans le cas des compositions a base de polychlorure de vinyle
La pr&ente partie de I’ISO 458 spkcifie une methode de deter-
plastifie, les courbes donnant le logarithme de la rigidit en tor- mination des temperatures correspondant a trois valeurs de la
sion en fonction de la tempbrature ont toutes une allure simi- rigidit en torsion caract&-istiques conventionnelles, des com-
laire et se presentent sous la forme d’un S inverse. Elles sont
positions plastifiees d’homopolym&es et de copolym&es de
habituellement caract&isees par trois zones particuli&es : chlorure de vinyle.
a) deux zones extrsmes oti generalement I’&olution de la
2 Refhence
rigidit en fonction de la temperature est relativement
lente :
IS0 458/l, Plastiques - Dgtermina tion de la rigidit en torsion
des plastiques souples - Partie 7 : Mkthode g&&ale.
1) une zone des valeurs elevees, correspondant 2 une
grande rigidit que certains auteurs ont assimili! 5 la
perte des propriWs blastiques. Clash et Berg111 en
3 Principe
avaient fix6 arbitrairement la valeur de la rigidit en tor-
sion 3 3,l x 109 dyn/cm**,
Application de I’ISO 458/l ZI des compositions plastifikes
d’homopolym&es et de copolym&es de chlorure de vinyle,
2) une zone des valeurs faibles, correspondant 5 une
consistant 2 dbterminer, pour un cas particulier de la metho-
grande souplesse. Dans ce cas, la rigidit en torsion cor-
de A avec un angle de torsion compris entre 55’ et 65O, les
respondante a et6 fixke arbitrairement a 42 kgf/cm***
temperatures correspondant i trois valeurs caracteristiques de
reprhsentant une valeur convenable pour des films
la rigidit en torsion ( r), soit : 300 MPa, 23 MPa et 4 MPa.
ayant, aux temperatures courantes d’utilisation, une
souplesse les rendant aptes 8 la confection d’articles tels
que rideaux, nappes et impermeabl
...

Norme internationale 45812
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION.ME>KfiYHAPOfiHAR OPTAHM3ALWlR l-IO CTAH~APTbl3AlJklt4.ORGANISATION INTERNATIONALE DE NORMALlSATtON
D6termination de la rigidit en torsion des
Plastiques -
plastiques souples -
Partie 2 I Application aux compositions plastifiees
d’homopolym&res et de copolym6wes de chlorure de vinyle
Plastics - Determination of stiffness in torsion of flexible materials - Part 2 : Application to plasticized compounds of
homopolymers and copolymers of vinyl chloride
Premiere bdition - 1985-04-01
R6f. n* : IS0 458/2-1985 (F)
iz
CDU 678.743.22 : 620.175251
essai de torsion, dbtermination, angle de torsion, rigidit& materiel d’essai.
Descripteurs : plastique, chlorure de vinyle, essai,
Prix base sur 2 pages
Avant-propos
L’ISO (Organisation inter-r-rationale de normalisation) est une federation mondiale
d’organismes nationaux de normalisation (comites membres de I’ISO). L’elaboration
des Normes internationales est confide aux comites techniques de I’ISO. Chaque
comite membre inter-es& par une etude a le droit de faire partie du comite technique
tree a cet effet. Les organisations internationales, gouvernementales et non gouverne-
mentales, en liaison avec I’ISO, participent egalement aux travaux.
Les projets de Normes internationales adopt& par les comites techniques sont soumis
aux comites membres pour approbation, avant leur acceptation comme Normes inter-
nationales par le Conseil de I’ISO. Les Normes internationales sont approuvees confor-
mement aux procedures de I’ISO qui requierent I’approbation de 75 % au moins des
comites membres votants.
La Norme internationale IS0 458/2 a ete elaboree par le comite technique lSO/TC 61,
Plas tiques.
Les Normes internationales IS0 458/l et IS0 458/2 annulent et remplacent la Recom-
mandation ISO/R 458-1965, dont elles constituent une revision technique.
Organisation internationale de normalisation, 1985
Imprimi! en Suisse
IS0 458/2-1985 (F)
NORME INTERNATIONALE
DGtermination de la rigidit en torsion des
Plastiques -
plastiques souples -
Partie 2 I Application aux compositions plastifi6es
d’homopolym&es et de copolym&res de chlorure de vinyle
0 Introduction
1 Objet et domaine d’application
Dans le cas des compositions a base de polychlorure de vinyle
La pr&ente partie de I’ISO 458 spkcifie une methode de deter-
plastifie, les courbes donnant le logarithme de la rigidit en tor- mination des temperatures correspondant a trois valeurs de la
sion en fonction de la tempbrature ont toutes une allure simi- rigidit en torsion caract&-istiques conventionnelles, des com-
laire et se presentent sous la forme d’un S inverse. Elles sont
positions plastifiees d’homopolym&es et de copolym&es de
habituellement caract&isees par trois zones particuli&es : chlorure de vinyle.
a) deux zones extrsmes oti generalement I’&olution de la
2 Refhence
rigidit en fonction de la temperature est relativement
lente :
IS0 458/l, Plastiques - Dgtermina tion de la rigidit en torsion
des plastiques souples - Partie 7 : Mkthode g&&ale.
1) une zone des valeurs elevees, correspondant 2 une
grande rigidit que certains auteurs ont assimili! 5 la
perte des propriWs blastiques. Clash et Berg111 en
3 Principe
avaient fix6 arbitrairement la valeur de la rigidit en tor-
sion 3 3,l x 109 dyn/cm**,
Application de I’ISO 458/l ZI des compositions plastifikes
d’homopolym&es et de copolym&es de chlorure de vinyle,
2) une zone des valeurs faibles, correspondant 5 une
consistant 2 dbterminer, pour un cas particulier de la metho-
grande souplesse. Dans ce cas, la rigidit en torsion cor-
de A avec un angle de torsion compris entre 55’ et 65O, les
respondante a et6 fixke arbitrairement a 42 kgf/cm***
temperatures correspondant i trois valeurs caracteristiques de
reprhsentant une valeur convenable pour des films
la rigidit en torsion ( r), soit : 300 MPa, 23 MPa et 4 MPa.
ayant, aux temperatures courantes d’utilisation, une
souplesse les rendant aptes 8 la confection d’articles tels
que rideaux, nappes et impermeabl
...