Standard Practice for Compatibility of Plasticizers in Poly(Vinyl Chloride) Plastics Under Compression

Importancia y uso:

5.1 It is possible for plasticizers to become less compatible in poly(vinyl chloride) resin when fused compound is subjected to compressive stress.

5.1.1 This test subjects a standard test specimen to a definite deformation and allows qualitative determination of the amount of spew that is capable of occurring over a period of time.

5.1.2 An apparent decrease in compatibility of plasticizers with subsequent exudation can cause excessive dirt pickup, marring of lacquered or varnished surfaces, sticky feel, and a number of other associated problems.

5.1.3 When a plasticized poly(vinyl chloride) sheet is stressed in compression by bending it through 180°, one way to relieve the stress is by migration of the plasticizer from the compressed area (inside of bend) to the area in tension (outside of bend). If these compressive stresses cannot be relieved rapidly by internal migration of plasticizer, then plasticizer will spew. The internal migration of plasticizer will continue and when a deficiency of plasticizer occurs at the compressed area spewed plasticizer will be reabsorbed. It is possible for certain plasticizers to spew and be reabsorbed quite rapidly. Less compatible plasticizers are capable of spewing early and continuing to spew throughout the test. A test of one week's duration is used for screening, while an extended test of seven weeks' duration is used for a complete profile.

Note 3: It is permissible for the seller and the purchaser to agree upon other test conditions of time, temperature, or relative humidity.

Subcomité:

D20.15

Volúmen:

08.02

Número ICS:

83.040.30 (Auxiliary materials and additives for plastics)

Palabras clave:

plasticizer compatibility; plasticizers; poly(vinyl chloride);