Polyvinylchloride - standard specification

Plasticizer testing is frequently done with polyviitylchloride, PVC, compositions. In such cases reference standard polymer is specified in Table 4 of standard. The standard also contains requirements for plasticizer sorption for various PVC grades. The method of determination of plasticizer sorption included in this standard is discussed under a separate heading in this chapter. 

Designation system was developed for vinyl chloride thermoplastic resins which may be used as the basis of specification. In respect to plasticizers, the system allows to include in specification, plasticizer absorption at room temperature, viscosity of paste, and rheological behavior of paste. The second part of ISO standard gives a list of ISO standards used for testing of properties included in designation system and describes preparation of sample. 

In standard classification for vinyl plastics used in biomedical applications, a plasticizer is specified with prefix letter The letter is followed by a number from 1 to 14 which characterizes the type of plasticizer (e g., 1 - none, 2 - adipic acid derivative, 3 -azelaic, 4 - benzoic, 5 - citric, 6 - isophthalic, 7 - myristic, 8 - phosphoric, 9 - phthalic, 10 - sebacic, 11 - terephthalic, 12 - poly ether, 13 - polyethylene glycol, 14 - polyesters, 999 - other). The second letter specifies secondary plasticizer (e.g., A - none, B - alkyl epoxy stearates, C - epoxidized tall oil, D - epoxidized soybean oil, E - epoxidized linseed oil, F - epoxidized sunflower oil, Z - other). This classification is used to guide design engineers. Classification is not applicable to long-term implants. If there is a conflict between provisions of this standard and detailed specification for a particular device, the latter takes precedence. 

---