# ISO 4901:1985 — Withdrawn and superseded ISO standards

For ISO 4901:1985, item title is Reinforced plastics based on unsaturated polyester resins — Determination of residual styrene monomer content; status code is 9599; successor is ISO/WD 4901 | ISO 4901:2011; withdrawn / published date is 1985-09-19, recorded from its source on 2026-08-05.

- **Identifier:** ISO 4901:1985 _(verified: appears in the quote below)_
- **Item title:** Reinforced plastics based on unsaturated polyester resins — Determination of residual styrene monomer content _(verified: appears in the quote below)_
- **Status code:** 9599 _(verified: appears in the quote below)_
- **Successor:** ISO/WD 4901 | ISO 4901:2011
- **Withdrawn / published date:** 1985-09-19 _(verified: appears in the quote below)_

## What the source says

> 10919,IS,,ISO 4901:1985,Reinforced plastics based on unsaturated polyester resins — Determination of residual styrene monomer content,Plastiques renforcés à base de résines de polyesters non saturés — Détermination du styrène monomère résiduel,1985-09-19,1,['83.120'],ISO/TC 61/SC 12,9599,,"[26316,52876]","['en','fr']",5,<p>The residual styrene monomer content in reinforced plastics based on unsaturated polyester (UP) resins is an important criterion in evaluating the degree of cure of UP resins in the polymerized state. The determination is carried out by extraction of the residual monomer styrene from the UP resin in the polymerized state using dichloromethane and subsequent gaschromatograp

## Source

- https://isopublicstorageprod.blob.core.windows.net/opendata/_latest/iso_deliverables_metadata/csv/iso_deliverables_metadata.csv

Last verified: 2026-08-05. Review by: 2027-02-01.
Part of [Withdrawn and superseded ISO standards](https://referencesource.org/iso-standard-supersessions/).