Effect of recycled poly(ethylene terephthalate) content on properties of extruded poly(ethylene terephthalate) sheets

Abstract

Sixty (60) polyethylene terephthalate (PET) sheets containing 0—100% recycled-PET (RPET) bottle flake were produced using industrial extruders. The PET/RPET sheets were characterized using differential scanning calorimetry, ultraviolet— visible spectroscopy, mechanical testing, and inductively coupled plasma—atomic emission spectroscopy (ICP—AES). The absorbance at 350 nm, %crystallinity, crystallization temperature, and crystallization peak offset were found to be both unaffected by a silicone mold release coating and reasonably valid indicators of %RPET. Mechanical testing determined that incorporating recycled content into virgin resin will significantly alter the composite mechanical properties; analysis indicated that there was approximately a 2-, 3-, and 30-MPa increase in stress at the proportional limit, stress at yield, and Young’s modulus, respectively, in the machine direction at 40% RPET concentration when compared to virgin resin. The ICP—AES determined that PET/RPET sheets can be safely used for food packaging as according to California Health and Safety Code.

Keywords

poly(ethylene terephthalate)PET post-consumer PCR recycling packaging

Get full access to this article

View all access options for this article.

References

Subramanian PM

Plastics recycling and waste management in the US. Resour Conserv Recycl2000; 28(3-4): 253-263.

Anonymous.

‘Municipal Solid Waste in the United States: 2007 Facts and Figures’, U.S. Environmental Protection Agency, Washington, DC, http://www.epa.gov/epawaste/nonhaz/municipal/pubs/msw07-rpt.pdf (accessed July 2008).

Schedler M.

‘A PET Recycling Status Report’, Resource Recycling , February 2 (accessed July 2008).

Fakirov S.

Polyethylene terephthalate. In:

Olabisi O

(ed.) Handbook of thermoplastics. New York, NY: Marcel Dekker, Inc., 1997 , pp.449-464.

Arroyo M.

Thermoplastic polyesters. In:

Olabisi O

(ed.) Handbook of thermoplastics. New York, NY: Marcel Dekker, Inc., 1997, pp.417-448.

Misra E.

Basavarajaiah S.

Kumar KR

and

Ravi P.

Effect of recycling on the properties of polyethylene terephthalate films . Polymer Int2000; 49(12): 1636-1640.

Awaja F.

and

Pavel D.

Recycling of PET. Eur Polym J2005; 41(7): 1453-1477.

Anonymous.

‘2007 Report on Post Consumer PET Container Recycling Activity’, NAPCOR, http://www.napcor.com/pdf/2007PET_Report.pdf (accessed July 2008).

Solamon AW

and

Fielder KJ

Practical uses of differential scanning calorimetry for plastics. In:

Bonilla J

and

Lobo H

(eds) Handbook of plastics analysis. New York, NY: Marcel Dekker, Inc., 2003, pp.79-109.

10.

Anonymous.

Astm D.

3418-03. Standard test method for transition temperatures and enthalpies of fusion and crystallization of polymers by differential scanning calorimetry. West Conshohocken, PA: ASTM International, 2003.

11.

Anonymous.

Astm D.

882-02. Standard test method for tensile properties of thin plastic sheeting. West Conshohocken, PA: ASTM International, 2002.

12.

Anonymous.

‘Toxics in Packaging Prevention Act’, California Government , http://www.dtsc.ca.gov/ToxicsInPackaging/upload/TiP_PreventionAct1209.pdf (accessed November 2008).

13.

Finn JD

A general model for multivariate analysis. New York: Holt, Rinehart and Winston, 1974, pp.296-327.

14.

IBM’s SPSS Statistical Routines, Release 16 were used in these analyses.

15.

Wilk MB

and

Gnanadesikan R.

Probability plotting methods for the analysis data. Biometrika1968; 55(1): 1-17.

16.

Chambers J.

Cleveland W.

Kleiner B.

and

Tukey P.

Graphical methods for data analysis. Monterey, Calif: Wadsworth, 1983.