Effect of chemical activity jumps on the viscoelastic behavior of an epoxy resin: Physical aging response in carbon dioxide pressure jumps

We report the results from tensile creep tests performed on an epoxy resin in the presence of carbon dioxide at different pressures (Pco2) and at a constant temperature below the glass-transition temperature. Time-Pco2 superposition was applied to the data to account for the plasticization effect because of the interaction between the carbon dioxide molecules and the polymer. In addition, physical aging of the epoxy films was investigated with sequential creep tests after carbon dioxide pressure down-jumps at constant temperature and after temperature down-jumps at constant carbon dioxide pressure. The isothermal pressure down-jump experiments showed physical aging responses similar to the isobaric temperature down-jump experiments. However, the aging rate for the CO2 jump was slightly lower than that for the temperature-jump (T-jump) experiments, and the retardation time for the Pco2-jump experiments was up to 6.3 times longer than for the T-jump conditions. The results are discussed in terms of classical physical aging and structural recovery frameworks, and speculation about the differences in the energy landscape resulting from the Pco2-jump and T-jump experiments is also made. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 2050–2064, 2002

[1]  D. R. Paul,et al.  EFFECT OF SUB-Tg ANNEALING ON CO2 SORPTION IN POLYCARBONATE. , 1978 .

[2]  D. Mangelinck,et al.  Physical aging of epoxy networks after quenching and/or plastic cycling , 1994 .

[3]  M. Paulaitis,et al.  Swelling and sorption in polymer-CO2 mixtures at elevated pressures , 1987 .

[4]  Andre Lee,et al.  The physical ageing response of an epoxy glass subjected to large stresses , 1990 .

[5]  Andre Lee,et al.  Effect of crosslink density on physical ageing of epoxy networks , 1988 .

[6]  C. Castellano,et al.  Glass temperature depression of polymer by use of mixed solvents: A colligative property , 1996 .

[7]  Gregory B. McKenna,et al.  Arrhenius-type temperature dependence of the segmental relaxation below Tg , 1999 .

[8]  K. Dalnoki-Veress,et al.  Brillouin light scattering studies of the mechanical properties of thin freely standing polystyrene films , 1998 .

[9]  F. Kohlrausch,et al.  Ueber die elastische Nachwirkung bei der Torsion , 1863 .

[10]  W. Sachse,et al.  Effects of high‐pressure CO2 on the glass transition temperature and mechanical properties of polystyrene , 1982 .

[11]  J. Hutchinson,et al.  Physical aging of polymers , 1995 .

[12]  D. Plazek,et al.  Physical aging of a polyetherimide: Creep and DSC measurements , 1995 .

[13]  J. Hutchinson,et al.  Isobaric volume and enthalpy recovery of glasses. II. A transparent multiparameter theory , 1979 .

[14]  Michael E. Paulaitis,et al.  GLASS TRANSITIONS IN POLYMER/CO2 MIXTURES AT ELEVATED PRESSURES , 1991 .

[15]  A. A. Rocha,et al.  Carbon dioxide sorption and transport in polycarbonate , 1976 .

[16]  Wallace,et al.  Influence of an impenetrable interface on a polymer glass-transition temperature. , 1995, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics.

[17]  A. J. Kovacs,et al.  Transition vitreuse dans les polymères amorphes. Etude phénoménologique , 1964 .

[18]  R. Landel,et al.  The Temperature Dependence of Relaxation Mechanisms in Amorphous Polymers and Other Glass-Forming Liquids , 1955 .

[19]  Forrest,et al.  Effect of Free Surfaces on the Glass Transition Temperature of Thin Polymer Films. , 1996, Physical review letters.

[20]  William J. Koros,et al.  Dilation of polymers by sorption of carbon dioxide at elevated pressures. 1. Silicone rubber and unconditioned polycarbonate , 1986 .

[21]  T. Fox.  Influence of Diluent and of Copolymer Composition on the Glass Temperature of a Poly-mer System , 1956 .

[22]  Graham Williams,et al.  Non-symmetrical dielectric relaxation behaviour arising from a simple empirical decay function , 1970 .

[23]  G. Dean,et al.  Effects of physical ageing on creep in polypropylene , 1988 .

[24]  W. Koros,et al.  CO2 sorption in poly(ethylene terephthalate) above and below the glass transition , 1978 .

[25]  Gregory B. McKenna,et al.  Large deformation response of polycarbonate: Time‐temperature, time‐aging time, and time‐strain superposition , 1997 .

[26]  L. Struik.  Physical aging in amorphous polymers and other materials , 1978 .

[27]  Joseph L. Keddie,et al.  Size-Dependent Depression of the Glass Transition Temperature in Polymer Films , 1994 .

[28]  J. H. Gibbs,et al.  Nature of the Glass Transition and the Glassy State , 1958 .

[29]  G. McKenna,et al.  On the Physics Required for Prediction of Long Term Performance of Polymers and Their Composites , 1994, Journal of research of the National Institute of Standards and Technology.

[30]  J. W. Barlow,et al.  Plasticization of glassy polymers by CO2 , 1985 .

[31]  I. Sanchez,et al.  Glass transition behavior including retrograde vitrification of polymers with compressed fluid diluents , 1992 .

[32]  C. Angell,et al.  Glass-forming liquids, anomalous liquids, and polyamorphism in liquids and biopolymers , 1994 .

[33]  Richard G. Gann,et al.  Evaluation of Alternative In-Flight Fire Suppressants for Full-Scale Testing in Simulated Aircraft Engine Nacelles and Dry Bays (NIST SP 861) , 1994 .

[34]  Joseph L. Keddie,et al.  Interface and surface effects on the glass-transition temperature in thin polymer films , 1994 .