Influence of Water Absorption on Transverse Tensile Properties and Shear Fracture Toughness of Glass/Polypropylene

Abstract

Water absorption characteristics, and developments of transverse tensile modulus and strength, and mode II fracture toughness with water absorption of a unidirectional glass/polypropylene (PP) composite have been examined. Immersion times up to 5 months at 50°C were employed. Overall, very small amounts of water were absorbed. The absorption of water was more rapid in distilled water than in seawater. No significant change in the transverse tensile modulus was observed after immersion, which is attributed to negligible softening of the highly crystalline PP matrix. The transverse tensile strength, very low initially, was also virtually unaffected by water absorption. The mode II fracture toughness, G_IIc , decreased significantly after water absorption. The reduction of G _IIc is attributed to degradation of the matrix due to water absorption as observed in the scanning electron microscope.

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References

1. Drzal, L. T. 1982. "Adhesion of Graphite Fibers to Epoxy Matrices: I. The Role of Fiber Surface Treatment," J. Adhesion, 37:1-30.

2. Springer, G. S. , editor. 1981. "Environmental Effects on Composite Materials," Technomic.

3. Charles, R. J. 1958. "Static Fatigue of Glass," J. Applied Physics, 29(11):1549-1560.

4. Hogg, P. J. and D. Hull . 1983. "Corrosion and Environmental Deterioration of GRP," in Developments in GRP Technology 1, B. Harris, ed., Elsevier, 2:37-90.

5. Johnston, N. J. , T. W. Towell and P. M. Hergenrother . 1991. "Physical and Mechanical Properties of High-Performance Thermoplastic Polymers and Their Composites," in Thermoplastic Composites Materials, L. A. Carlsson, ed., Elsevier Science, pp. 27-71.

6. Pomies, F. 1992. "Degradation of Compositc Materials in a Marine Environment," MS Thesis, Department of Mechanical Engineering, Florida Atlantic University, Boca Raton, Florida, August 1992.

7. Pomies, F. and L. A. Carlsson . 1994. "Analysis of Modulus and Strength of Dry and Wet Thermoset and Thermoplastic Composites Loaded in Transverse Tension," J. Compos. Mater., 28:22-35.

8. Pomies, F. , L. A. Carlsson and J. W. Gillespie, Jr. 1995. "Marine Environmental Effects on Polymer Matrix Composites," to appear in Composite Materials, Fatigue and Fracture (Fifth Conference), ASTM STP 1230.

9. Juska, T. 1994. "Effect of Water Immersion on Fiber/Matrix Adhesion in Thermoplastic Composites," J. Thermoplast. Compos. Mater., 6:256-274.

10.

10. Wilkins, D. J. , J. R. Eisenmann , R. A. Camin , W. S. Margolis and R. A. Benson . 1982. "Characterizing Delamination Growth in Graphite-Epoxy," in Damage in Composite Materials, ASTM STP 775, pp. 168-183.

11.

11. Davies, P. , F. Rannou , W. J. Cantwell , F. Pomies and L. A. Carlsson . 1993. "Durability of Composite Materials in a Marine Environment-A Fracture Mechanics Approach," Proc. ICCM-9, Volume II, Madrid, Spain, pp. 308-315.

12.

12. Davies, P. and M. L. Benzeggagh . 1989. "Interlaminar Mode I Fracture Testing," in Application of Fracture Mechanics to Composite Materials, K. Friedreich, ed., Elsevier, pp. 81-112.

13.

13. Russell, A. J. and K. N. Street . 1982. "Factors Affecting the Interlaminar Fracture Energy of Graphite/Epoxy Laminates," Proc. ICCM-4, Tokyo, Japan, pp. 279-286.

14.

14. Kenig, S. , A. Moshonov , A. Shucrun and G. Marom . 1989. "Environmental Effects on Shear Delamination of Fabric Reinforced Epoxy Composites," Int. J. Adhesion & Adhesives, 9(1):38-45.

15.

15. Davies, P. and W. J. Cantwell . 1994. "Fracture of Glass/Polypropylene Laminates: Influence of Cooling Rate after Moulding," Composites, 25(9):869-877.

16.

16. Carlsson, L. A. and R. B. Pipes . 1987. "Experimental Characterization of Advanced Composite Materials," Prentice-Hall.

17.

17. 1991. ICI Materials, Wilton Middlesbrough UK, Provisional Product Information on "Plytron" Glass/PP, September.

18.

18. Gillespie, J. W., Jr. and L. A. Carlsson . 1990. "Interlaminar Fracture of Laminated Composite Materials," in Delaware Composites Design Encyclopedia, Vol. 6, L. A. Carlsson and J. W. Gillespie, Jr. , rev. eds., Technomic, pp. 113-160.

19.

19. Davies, P. , C. Moulin , H. H. Kausch and M. Fischer . 1990. "Measurement of G,, and G,,(in Carbon/Epoxy Composites," Comp. Sci. & Tech., 39:193-205.

20.

20. Cooper, G. A. and A. Kelly . 1969. "Role of the Interface in the Fracture of Fiber-Composite Materials," in Interfaces in Composites, ASTM STP 452, pp. 90-106.

21.

21. McCrum, N. G. , C. P. Buckley and C. B. Bucknall . 1988. "Principles of Polymer Engineering," Oxford Science Publications.

22.

22. Carlsson, L. A. , J. W. Gillespie, Jr. and B. R. Trethewey . 1986. "Mode II Interlaminar Fracture of Graphite/Epoxy and Graphite/PEEK," J. Reinf. Plast. Compos., 5:170-187.