Deterioration of polyethylene pipes exposed to water containing chlorine dioxide

Yu, W; Azhdar, B; Andersson, D; Reitberger, T; Hassinen, J; Hjertberg, T; Gedde, UW

HERO ID

912592

Reference Type

Journal Article

Year

2011

HERO ID 912592
In Press No
Year 2011
Title Deterioration of polyethylene pipes exposed to water containing chlorine dioxide
Authors Yu, W; Azhdar, B; Andersson, D; Reitberger, T; Hassinen, J; Hjertberg, T; Gedde, UW
Journal Polymer Degradation and Stability
Volume 96
Issue 5
Page Numbers 790-797
Abstract Chlorine species used as disinfectants in tap water have a deteriorating effect on many materials including polyethylene. There are only very few scientific reports on the effect on polyethylene pipes of water containing chlorine dioxide. Medium-density polyethylene pipes stabilized with hindered phenol and phosphite antioxidants were pressure tested with water containing 4 ppm chlorine dioxide at 90 degrees C and pH = 6.8 as internal medium. The stabilizers were rapidly consumed towards the inner pipe wall; the rate of consumption was four times greater than in chlorinated water (4 ppm, pH = 6.8) at the same temperature. The depletion of stabilizer occurred far into the pipe wall. A supplementary study on a polymer analogue (squalane) containing the same stabilizer package showed that the consumption of the phenolic antioxidant was 2.5 times faster when exposed water containing chlorine dioxide than on exposure to chlorinated water. The subsequent polymer degradation was an immediate surface reaction. It was confirmed by differential scanning calorimetry, infrared spectroscopy and size exclusion chromatography that in the surface layer which came into contact with the oxidising medium, the amorphous component of the polymer was heavily oxidized leaving a highly crystalline powder with many carboxylic acid chain ends in extended and once-folded chains. Scanning electron microscopy showed that propagation of cracks through the pipe wall was assisted by polymer degradation. (C) 2011 Elsevier Ltd. All rights reserved.
Doi 10.1016/j.polymdegradstab.2011.02.009
Wosid WOS:000290078200009
Url http://linkinghub.elsevier.com/retrieve/pii/S0141391011000759
Is Certified Translation No
Dupe Override No
Is Public Yes
Keyword Polyethylene pipes; Chlorine dioxide; Degradation
Is Qa No