BS EN ISO 177:2000 pdf free.Plastics — Determination of migration of plasticizers.
BS EN ISO 177 The test specimens shall be in the form of discs50 mm ± 1 mm in diameter and at least 0,5 mm in thickness,cut from a compression-moulded (see ISO 293) or injection-moulded (see ISO 294) sheet of suitable thickness.
The surface of the test specimens shall be sufficiently smoothto ensure continuous contact with the absorbent backing discs(5.6).
lin the case of films,the test specimen of not less than0,5 mm thickness shali be produced by pressing an adequatenumber of films at a suitable temperature for about 1 min.
If the test is intended to determine the migration from afinished product,the latter shall be tested at a uniformthickness.
If the product to be tested consists of a support (fabric.paper or other suitable material), coated on one face only bythe spreading or calendering of a plasticized resin isuch asfabrics coated with vinyl resins or with similar productst, thetest specinens shall consist of two discs cut from the material,itself and superposed in such a way that the uncoated surfacesof the support are touching and the plastic is situated on theother faces of the sandwich so formed.
Three test specimens shall be tested for each material.
Unless otherwise specified, the test specimens and absorbentbacking discs (5.6) shall be conditioned in one of theatmospheres specified in ISO 291.After conditioning,weigh the test specimens lclause 6)and the discs 45.6) to the nearest 0,001 g and determine theirmean thickness to the nearest 0,01 mm.
If the test is intended to determine the characteristics ofparticular plasticizers, standard compounds of a specified com-position shall be used， as agreed between the interestedparties.
To equalize the distribution of pressure between theabsorbent backing disc and the test specimen, a sheet of rub-ber shall be inserted between the absorbent backing disc andthe glass plate.The absorbent backing disc shall be separatedfrom the sheet of rubber by aluminium foil.
Place one of the 5 kg weights {5.5) on the assembly ofdiscs and plates to be tested and place the assembly in the oven(5.3),maintained at a temperature of 70 ± 2°c.
lt is permissible to superimpose several assernblies, but five atmost, separated by glass plates,thus forming a column loadedwith a single 5 kg weight. In this event, the temperature shallbe measured directly at the interior of the stack, for examplebetween an absorbent backing disc and the sheet of rubber in-serted to equalize the pressure.
NOTE- When it is required to take account of the service temperature.of the material,the test should be conducted at the temperaturerecommended in the specification for the application of the material. Inthe absence of any particular specification, if it is desired to perform atest at a temperature either lower or higher than 70 °C.50 C or 85 ℃,respectively.should be used.
Fresh absorbent backing discs shall be used for each test.
After 24 h, remove the assemblies from the oven.Separate the test specimens from the absorbent backing discsand recondition all of them under the same conditions as thoseapplied prior to the initial weighing. Reweigh the testspecimens and the absorbent backing discs.BS EN ISO 177 pdf download.