Simulated Low Earth Orbit Environment Interaction with Different Types of Polyethylene

Abstract

The present study investigated the interactions of four different types of polyethylene (PE) surfaces with RF oxygen plasma components, simulating the low Earth orbit (LEO) environment. The samples were exposed in the plasma afterglow, with and without the plasma-generated vacuum UV (VUV) radiation. The polymers studied were low-density polyethylene (LDPE), ultra high molecular weight polyethylene (UHMWPE), high-density polyethylene (HDPE), and a composite of highly-oriented fibres of ultra-high molecular weight polyethylene (PolyEitan) having crystalline-to-amorphous phases ratio of 65, 74, 87 and 92%, respectively. Erosion of the LDPE, UHMWPE, and HDPE samples under atomic oxygen (AO) irradiation showed an etching rate dependence on the degree of crystallinity - the higher the crystallinity level the lower the erosion rate. The addition of VUV radiation to the AO flux resulted in a significant increase of the etching rate. An increase of the crystallinity level resulted in a decrease of the total oxygen uptake and an increase of the surface roughness. The composite polyethylene, although highly crystalline, revealed similar erosion rate and chemical composition changes as highly amorphous LDPE. The erosion mechanism of the different PE samples under AO or AO+VUV is discussed in terms of the initial internal structure.

Keywords

Atomic oxygen vacuum UV polyethylene LEO environment

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References

[1] Reddy M R 1995 J. Mater Sci. 30, 281-281

[2] Packirisamy S , Schwam D and Litt M H 1995 J. Mater Sci. 30, 308-308

[3] Koontz S L , Kalbyn and Leger L J 1991 J. Spacecraft 28, 3154-3154

[4] Reddy M R , Srinivasamurthy N and Agrawal B L 1992 ESA Journal 16, 193-193

[5] deGroth K and Banks B 1991 Proc ofFirst LDEF Post-Retrieval Symposium, Kissimmee, Florida, July 1991, pp 2-8

[6] Ferguson D C 1984 Proc of the 13th Space Simulation Conf, Orlando, FL, 1984, NASA CP 2340: 205-221.

[7] Tennyson R C 1991 Can. J. Phys. 69, 1190-1190

[8] Iskanderova Z A , Kleiman J I , Gudimenko Yu and Tennyson R C 1995 J. Spacecrafi 32, 878-878

[9] Vered R , Matlis S , Nahor G , Lempert G D , Grossman E , Marom G and Lifshitz Y 1994 Surface & Interface Anal. 22, 532-532

10.

[10] Banks B A , de Groth S K , Stidhman K K , Gebauer L and LaMoreaux C M 1995 NASA Technical Memorandum 106855 pp 1-15

11.

[11] Townsend J A , 1996 Proc. 19th Space Simulation Confy, Baltimore MD, Oct 29-31 pp 249-258

12.

[12] Kearns D M , Gillen D R , bulot D , McCullough R W , Thompson W R , Cosimini G J , Nelson E , Chow P P and Klaassen 2001 J. Vac. Sci. Technol. A19, 993-993

13.

[13] Rein D M, "ykhansky L and Cohen Y 2001 Ultra-high molecular weight polyolefin fiber composite matrix andprocessfor manufacture there of US Patent 6,172,163. (January 9, 2001)

14.

[14] Bellamy L J 1958 The Infrared Spectra of Complex Molecules second edn ( New York: John Wiley & Sons, Inc. )

15.

[15] ASTM E 490, Dec. 1999

16.

[16] Shahin M M , Olley R H and Blissett M J 1999 J. Polymer SciL. Part B 37, 2279-2279