This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. Designation: F2466 - 10 (Reapproved 2018) INTERNATIONAL Standard Practice for Determining Silicone Volatiles in Silicone Rubber for Transportation Applications This standard is issued under the fixed designation F2466; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval. and measured by gas chromatography (GC), and (4) the GC 1. Scope 1.1 This practice covers a means to determine the percent results are quantified using a siloxane calibration. silicone-producing volatiles present in heat-cured silicone 4. Significance and Use rubber and room temperature-cured silicones (RTV). 4.1 Use of this practice in conjunction with realistic maxi- 1.2 Silicone-producing volatiles contribute to fouling of mum volatility tolerance level can help minimize the risk of oxygen sensor systems used in the control of vehicle emis- oxygen sensor dysfunction from formed-in-place-sealants in sions. transportation applications. This practice provides a method for 1.3 This standard does not purport to address all of the determination of percentage volatiles in silicone elastomers safety concerns, if any, associated with its use. It is the The volatile silicones from a commercial silicone are primarily responsibility of the user of this standard to establish appro- cyclo dimethyl-siloxane. Other species present having GC priate safety, health, and environmental practices and deter- retention times similar to those of the cyclics are assumed to be mine the applicability of regulatory limitations prior to use. silicone as well. 1.4 This international standard was developed in accor- dance with internationally recognized principles on standard- 5. Apparatus ization established in the Decision on Principles for the 5.1 Gas Chromatograph, fused silica capillary column sys- Development of International Standards, Guides and Recom- tem equipped with a flame ionization detector, split-type mendations issued by the World Trade Organization Technical capillary column injector, temperature programming capability Barriers to Trade (TBT) Committee. and an appropriate data recording system. An alternative unit 2. Referenced Documents conductivity detector, or as agreed upon between producer and 2.1 ASTM Standards:2 user. Specific column and operating conditions should be D3182 Practice for Rubber-—Materials, Equipment, and Pro- selected to optimize instrument response and chromatographic cedures for Mixing Standard Compounds and Preparing resolution, particularly separation of the internal standard from Standard Vulcanized Sheets extracted sample components. E177 Practice for Use of the Terms Precision and Bias in 5.2 Column, suggested to be used is 30 to 60 m by 0.25 mm ASTM Test Methods with 0.25 to 1.5 μm DB-1 or DB-5 fused silica capillary E691 Practice for Conducting an Interlaboratory Study to column or equivalent. Determine the Precision of a Test Method 5.3 Operating conditions are: 3. Summary of Practice 5.3.1 Column-50 to 320°C at 10°C/min (a post-analysis 3.1 This practice consists of four (4) basic steps: (l) the period may be required to elute higher boiling components silicone is cured to its elastomeric form, (2) the volatiles are prior to subsequent analyses). extracted from the cured material, (3) the extract is separated 5.3.2 Injector290°C. 5.3.3 Detector—325°C. 5.3.4 Sample Size-1 μL. This under the jurisdiction of ASTM Committee F03 on Gaskets and 5.3.5 Injector Split Ratio—2:1 to 50:1 (ad