Weldability of pipe grade polyethylenes as realized from thermal and mechanical properties assessments

Vahabodin Goodarzi; Zahed Ahmadi; Mohammad Reza Saeb; Farkhondeh Hemmati; Mehdi Ghaffari; Krzysztof Formela

doi:10.1515/polyeng-2015-0242

Article

Weldability of pipe grade polyethylenes as realized from thermal and mechanical properties assessments

Vahabodin Goodarzi , Zahed Ahmadi , Mohammad Reza Saeb , Farkhondeh Hemmati , Mehdi Ghaffari and Krzysztof Formela

Published/Copyright: February 6, 2016

Published by

Become an author with De Gruyter Brill

Submit Manuscript Author Information

From the journal Journal of Polymer Engineering Volume 36 Issue 8

Abstract

Since polyethylene (PE) has been widely accepted for the production of high-pressure fluid conveying pipelines, studies devoted to weldability of PE connections were always of major importance. In this study, two industrial PE grades designed for pipe production, namely PE80 and PE100, were injection molded, cut, and then welded as PE100-PE100, PE100-PE80, and PE80-PE80. The heat-welded joints were assessed by differential scanning calorimetry and tensile measurements. The results obtained from thermal and mechanical analyses were compared with equivalents for aged samples. Thermal analysis revealed that the melting point of the PE100-PE100 sample is obviously larger than the one for the PE80-PE80 joint, for the PE80 chains deteriorate the crystallization of PE100. Further, the PE80-PE80 sample showed the lowest lamellar thickness and crystalline molecular weight among the studied joints. The aging process was found to increase lamellar thickness and molecular weight, though in the PE100-PE100 sample such quantities very limitedly increased. The yield stress of aged joints was higher than that for just-prepared samples, while an inverse trend was seen for strain at break. From a practical viewpoint, the PE100-PE100 welds offer better properties.

Keywords: crystallinity; lamella thickness; mechanical properties; polyethylene; weldability

Corresponding authors: Zahed Ahmadi, Color and Polymer Research Center, Amirkabir University of Technology, Postal Code 15875-4413, Tehran, Iran, e-mail: zahmadi@aut.ac.ir; and Mohammad Reza Saeb, Department of Resins and Additives, Institute for Color Science and Technology, PO Box 16765-654, Tehran, Iran, e-mail: saeb-mr@icrc.ac.ir

References

[1] Ebewele RO. Polymer Science and Technology, CRC Publisher: New York, 1996.Search in Google Scholar

[2] Gu R, Sain M, Kokta BV. Polym. Compos. 2015, 36, 287–293.10.1002/pc.22942Search in Google Scholar

[3] Kazemi Y, Cloutier A, Rodrigue D. Polym. Compos. 2013, 34, 487–493.10.1002/pc.22442Search in Google Scholar

[4] Fonda RW, Bingert JF, Colligan KJ. Scripta Mater. 2004, 51, 243–248.10.1016/j.scriptamat.2004.04.017Search in Google Scholar

[5] Ilie M, Kneip JC, Matte S, Nichici A, Roze C, Girasole T. Infrared Phys. Technol. 2007, 51, 73–79.10.1016/j.infrared.2007.02.003Search in Google Scholar

[6] Oliveira MJ, Bernardo CA, Hemsley DA. Polym. Eng. Sci. 2001, 41, 1913–1922.10.1002/pen.10888Search in Google Scholar

[7] Simar A, Bréchet Y, Meester B, Denquin A, Pardoen T. Mater. Sci. Eng. A 2008, 486, 85–95.10.1016/j.msea.2007.08.041Search in Google Scholar

[8] Liu LM, Wang HY, Zhang ZD. Scripta Mater. 2007, 56, 473–476.10.1016/j.scriptamat.2006.11.034Search in Google Scholar

[9] Sancaktar E, Walker E. J. Appl. Polym. Sci. 2004, 94, 1986–1998.10.1002/app.21102Search in Google Scholar

[10] Chebbo Z, Vincent M, Boujlal A, Gueugnaut D, Tillier Y. Polym. Eng. Sci. 2015, 55, 123–131.10.1002/pen.23878Search in Google Scholar

[11] Visco AM, Brancato V, Torrisi L, Cutroneo M. Int.J. Polym. Anal. Chara. 2014, 19, 489–499.10.1080/1023666X.2014.921108Search in Google Scholar

[12] Froelich K, Rauner H, Scheiba F, Roth C, Ehrenberg H. J. Power. Sour. 2014, 267, 260–268.10.1016/j.jpowsour.2014.05.026Search in Google Scholar

[13] Junior WS, Handge UA, dos Santos JF, Abetz V, Amancio-Filho ST. Mater. Desig. 2014, 64, 246–250.10.1016/j.matdes.2014.07.050Search in Google Scholar

[14] Lee BY, Kim JS, Lee SY, Kim YK. Mater. Des. 2012, 35, 626–632.10.1016/j.matdes.2011.10.014Search in Google Scholar

[15] Oliveira MJ, Hemsley DA. British Polym. J. 1985, 17, 269–274.10.1002/pi.4980170304Search in Google Scholar

[16] Ge T, Grest GS, Robbins MO. Macromolecules 2014, 47, 6982–6989.10.1021/ma501473qSearch in Google Scholar

[17] Liu SJ, Chang IT, Hung SW. Polym. Compos. 2001, 22, 132–141.10.1002/pc.10525Search in Google Scholar

[18] Eduljee RF, Gillespie JW. Polym. Compos. 1989, 10, 184–193.10.1002/pc.750100306Search in Google Scholar

[19] EL-Bagory TMAA, Sallam HEM, Younan MYA. Theor. Appl. Fract. Mech. 2014, 74, 164–180.10.1016/j.tafmec.2014.09.008Search in Google Scholar

[20] Oliveira MJ, Bernardo CA, Hemsley DA. Polym. Eng. Sci. 2002, 42, 146–151.10.1002/pen.10935Search in Google Scholar

[21] Balkan O, Demirer H, Ezdeşir A, Yıldırım H. Polym. Eng. Sci. 2008, 48, 732–746.10.1002/pen.21014Search in Google Scholar

[22] Oliveira MJ, Hemsley DA. Polym. Eng. Sci. 2000, 40, 2037–2045.10.1002/pen.11336Search in Google Scholar

[23] Wunderlich B, Dole M. J. Polym. Sci. 1957, 24, 201–213.10.1002/pol.1957.1202410604Search in Google Scholar

[24] Sperling LH. Introduction to Physical Polymer Science, Wiley: New York, 2006.10.1002/0471757128Search in Google Scholar

[25] Leskovics K, Kollar M, Barczy P. Mater. Sci. Eng. A 2006, 419, 138–143.10.1016/j.msea.2005.12.019Search in Google Scholar

[26] Capaccio G, Crompton TA, Ward IM. J.Polym. Sci. Polym. Phys. 1976, 14, 1641–1658.10.1002/pol.1976.180140910Search in Google Scholar

Received: 2015-6-5

Accepted: 2015-11-12

Published Online: 2016-2-6

Published in Print: 2016-10-1

You are currently not able to access this content.

Articles in the same Issue

https://doi.org/10.1515/polyeng-2015-0242

Keywords for this article

crystallinity; lamella thickness; mechanical properties; polyethylene; weldability