What is ISO 248‑1- Hot-mill method and oven method about?
ISO 248‑1 is the first part of the multi-series standard that specifies two methods for the determination of volatile-matter content in raw rubbers by using a hot mill or an oven.
These are rubbers having an unsaturated carbon chain, for example, natural rubber and synthetic rubbers derived at least partly from di-olefins.
Note 1: The two methods do not necessarily give identical results. Therefore, in the case of dispute, the oven method, procedure A, is the reference method.
Note 2: The applicability of each test method to various types of rubber is summarized in Annex A.
Note 3: These methods are applicable to the determination of the volatile-matter content in the “R” group of rubbers listed in ISO 1629.
Note 4: These methods can also be applicable to other raw rubbers, but in these cases, it is necessary to demonstrate that the change in mass is due solely to loss of actual volatile matter and not to rubber degradation.
Note 5: The hot-mill method is not applicable to natural rubber, to synthetic rubbers which are too difficult to handle on a hot mill or to synthetic rubbers in powder or chip form.
Who is ISO 248‑1 for- Hot-mill method and oven method?
ISO 248‑1 on the determination of volatile-matter content in raw rubber-Hot-mill method is useful for:
- Raw rubber suppliers
- Manufacturers of raw rubber
- Entities dealing with raw rubber
- Testing laboratories
Why should you use ISO 248‑1- Hot-mill method and oven method?
Natural rubber is used in applications requiring a high level of wear and heat resistance. Thanks to its strength and compressibility, natural rubber is used in engineering applications, like anti-vibration mounts, drive couplings, springs, bearings, rubber bands, and adhesives.
ISO 248‑1 gives you information about methods for the determination of volatile-matter content in raw rubbers by using a hot mill or an oven.
What’s changed since the last update?
BS ISO 248‑1:2021 supersedes ISO 248‑1:2011, which is withdrawn.
The main changes compared to the previous edition are as follows:
- In 6.2.1, update of the tolerance temperature of the oven
- In 6.3.1 and 6.3.2, update of the procedure: mass of the test sample, drying of the test portion, temperature, requirements on the aluminium tray
- Update of the formulae
- In Annex B, update of the homogenization procedure for natural rubber
- In Annex C, addition of the precision data from an ITP conducted in 2020 for natural rubber