Limits in the validity of Arrhenius predictions for field ageing of a silica filled polychloroprene in a marine environment

Abstract Accelerated ageing in natural sea water at different temperatures from 20 °C to 80 °C was performed on a silica filled polychloroprene rubber. Degradation when monitored with mechanical properties at both macroscopic and microscopic scale led to a large increase of the modulus coupled with a strong decrease of strain and stress at break. Data from tensile tests were used for lifetime prediction with an Arrhenius extrapolation for modulus, strain and stress at break. The validity of this lifetime prediction was evaluated using a 23 year-old sample aged in natural conditions. Strain at break could be predicted using an Arrhenius extrapolation with an activation energy of 50 kJ/mol. However, an extrapolation based on linear Arrhenius behaviour did not apply for modulus and stress at break due to the presence of a degradation profile across the sample. These observations confirmed that strain at break is not governed by bulk properties of samples but by the degradation rate at the external surface of the sample ( i.e. in contact with water).

[1]  Kenneth T. Gillen,et al.  An ultrasensitive technique for testing the Arrhenius extrapolation assumption for thermally aged elastomers , 1995 .

[2]  D. K. Ottesen,et al.  Oxidation profiles of thermally aged nitrile rubber , 1998 .

[3]  F. Gugumus.  Effect of temperature on the lifetime of stabilized and unstabilized PP films , 1999 .

[4]  David R. Bauer,et al.  Correlation of Rubber Properties between Field Aged Tires and Laboratory Aged Tires , 2005 .

[5]  K. Gillen,et al.  Quantitative model for the time development of diffusion-limited oxidation profiles , 1997 .

[6]  K. Gillen,et al.  Modulus profiling of polymers , 1987 .

[7]  L. Audouin,et al.  Kinetic modelling of the thermal oxidation of polyisoprene elastomers. Part 1: Unvulcanized unstabilized polyisoprene , 2007 .

[8]  D. Choqueuse,et al.  Durability of polydicyclopentadiene under high temperature, high pressure and seawater (offshore oil production conditions) , 2013 .

[9]  D. K. Ottesen,et al.  Correlation of Chemical and Mechanical Property Changes During Oxidative Degradation of Neoprene , 2000 .

[10]  A. Stevenson,et al.  The effect of 42 year immersion in sea-water on natural rubber , 1986 .

[11]  L. Audouin,et al.  Hydroperoxide build-up in the thermal oxidation of polypropylene – A kinetic study , 2007 .

[12]  Helena Janik,et al.  Degradation of polyurethanes in sea water , 2002 .

[13]  D. Derzon,et al.  Evidence of non-Arrhenius behaviour from laboratory aging and 24-year field aging of polychloroprene rubber materials , 2005 .

[14]  G. Pharr,et al.  An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments , 1992 .

[15]  C. M. Roland,et al.  Aging of Natural Rubber in Air and Seawater , 2001 .

[16]  K. Gillen,et al.  Rigorous experimental confirmation of a theoretical model for diffusion-limited oxidation , 1992 .

[17]  Guy Evrard,et al.  Accelerated ageing of polyurethanes for marine applications , 2007 .

[18]  J. Koenig,et al.  FTIR imaging of oxidation of polyisoprene. 2. The role of N-phenyl-N'-dimethyl-butyl-p-phenylenediamine antioxidant , 2003 .

[19]  D. Oldfield,et al.  Long term natural ageing of silicone elastomers , 1996 .

[20]  L. Audouin,et al.  Kinetic modelling of the thermal oxidation of polyisoprene elastomers. Part 2: Effect of sulfur vulcanization on mass changes and thickness distribution of oxidation products during thermal oxidation , 2007 .

[21]  Yann Marco,et al.  Ageing mechanism and mechanical degradation behaviour of polychloroprene rubber in a marine environment: Comparison of accelerated ageing and long term exposure , 2012 .

[22]  K. Gillen,et al.  Accelerated aging and lifetime prediction: Review of non-Arrhenius behaviour due to two competing processes , 2005 .

[23]  A. Andrady,et al.  Outdoor weathering of selected polymeric materials under marine exposure conditions , 1989 .

[24]  Kenneth T. Gillen,et al.  Extrapolation of Accelerated Aging Data - Arrhenius or Erroneous? , 1997 .