ISO 15038 pdf download

ISO 15038 pdf download.Plastics — Organic-perester crosslinking agents for unsaturated-polyester thermosetting materials 1 Scope This International Standard specifies a method of determining the total active-oxygen content of organic peresters. It applies to those peresters used to initiate crosslinking of unsaturated-polyester thermosets. The peresters most widely used in the crosslinking of unsaturated-polyester resins are given in Table 1 .Butyl peresters may contain traces of tert -butyl hydroperoxide (TBHP), the active oxygen in which can be determined separately from that in the perester itself (see annex A). The active-oxygen content of the perester alone can then be obtained by subtraction. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this International Standard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards. ISO 385-1 :1 984, Laboratory glassware — Burettes — Part 1 : General requirements. ISO 648:1 977, Laboratory glassware — One-mark pipettes. ISO 3696:1 987, Water for analytical laboratory use — Specification and test methods. 3 Terms and definitions For the purposes of this International Standard, the following definitions apply: 3.1 active oxygen of an organic perester oxygen, liberated by an organic perester, capable of initiating crosslinking of organic compounds which have a C=C double bond such as unsaturated-polyester resins 3.2 perester a peroxide obtained by the reaction of an acid chloride with a hydroperoxide in accordance with the following equation [using tert -butyl hydroperoxide (TBHP) as an example]: 5 Reagents 5.1 Water, grade 3 as defined in ISO 3936, for use in preparing all the solutions listed below and in all other operations. 5.2 Sodium thiosulfate, standardized solution, c(Na 2 S 2 O 3 ) = 0,1 mol/l. 5.3 Glacial acetic acid. 5.4 Isopropanol, analytical grade. 5.5 Copper(II) chloride, 1 0 g/l aqueous solution (shelf life 6 months). 5.6 Potassium iodide, saturated solution freshly prepared from 1 00 g of KI and 1 00 ml of water (shelf life 1 day). 5.7 Nitrogen or carbon dioxide, purity > 99,9 %. 7 Procedure Pour 40 ml of isopropanol (5.4) and 1 5 ml...