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E-1 APPENDIX E Proposed Draft Standard Specification for PCR MCR High-Density PE Bottles for Use in AASHTO-Approved Corrugated Drainage Pipe

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E-2 DRAFT ____________________________________________________________ Draft Standard Specification for Post-Consumer Recycled Mixed-Color Reprocessed High Density Polyethylene Bottles for Use in AASHTO Approved Corrugated Drainage Pipe AASHTO Draft Standard XXX-XX ____________________________________________________________ 1. SCOPE 1.1 This specification covers the quality of post-consumer recycled, mixed-color, reprocessed, high density polyethylene bottles for use in AASHTO approved corrugated drainage pipe. 1.2 This specification presents a set of properties to be met for the resin. 1.3 This specification can be used by recycled resin suppliers as part of manufacturing quality control (MQC), or by pipe manufacturers or independent bodies as manufacturing quality assurance (MQA). ______________________________________________________________________ 2. REFERENCED DOCUMENTS 2.1 ASTM Standards: D638, Test Method for Tensile Properties of Plastics D792, Test Methods for Density and Specific Gravity (Relative Density) of Plastics by Displacement D1238, Test Method for Melt Flow Rates of Thermoplastics by Extrusion Plastometer D1505, Test Method for Density of Plastics by the Density-Gradient Technique D4218, Test Method for Determination of Carbon Black Content in Polyethylene Compounds By the Muffle-Furnace Technique D4703, Practice for Compression Molding Thermoplastic Materials into Test Specimens, Plaques, or Sheets D5630, Test Method for Ash Content in Plastics ______________________________________________________________________ 3. TERMINOLOGY 3.1 Post-Consumer Recycled HDPE (PCR-HDPE) Polyethylene that has been discarded by consumers after use, then collected, cleaned, and washed. The density is greater than 0.940 g/cm3 and typical sources include primarily bottles and some bags.

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E-3 3.2 PCR-HDPE Regrind Post-Consumer Recycled HDPE that has been cleaned, washed and ground into plastic chips. 3.3 Reprocessed PCR-HDPE Post-Consumer Recycled HDPE that has been cleaned, washed, melt-filtered, and pelletized. Commonly known as "Repro." 3.4 Mixed-Color PCR-HDPE Post-Consumer Recycled HDPE that is composed of mostly colored detergent bottles. 3.5 Natural PCR-HDPE Post-Consumer Recycled HDPE that is composed of milk bottles. ______________________________________________________________________ 4. PROPERTIES 4.1 The required properties for PCR mixed-color reprocessed resin are given in Table 1. 4.2 Specific details of the tests are found in Section 7. Table 1. Required properties for PCR mixed-color reprocessed resin. Property Test Method Sample Specified Frequency Value Density ASTM D1505 Pellets/Plaque 0.945-0.960 1 per shift ASTM D792 g/cm Melt Index ASTM D1238 Pellets/Plaque <0.60 g/10 min 1 per shift 190C/2.16 Kg % Volatiles 175C/1 Hour Pelletsa <0.2 % Certifyb % Ash ASTM D5603 Pellets/Plaque <1.5 % 1 per shift % PP DSC Plaque <10.0 % 1 per lotc Yield Stress ASTM D638d Plaque >3500 psi 1 per lot (psi) Break Strain ASTM D638e Plaque >100 % 1 per lot (%) a Tested on pellet samples before melt blending. b Manufacturer will provide a certificate stating their material will lose less than 0.2% of its weight when a 2.000 0.100 g sample is heated at 350F for 1 hour. c A production lot is defined as either a truckload, or one compartment of a railcar. Its weight is generally between 40,000 and 50,000 lb. d Strain rate shall be 2.0 in. per minute. e Assume 2.0-in. gage length.

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E-4 ______________________________________________________________________ 5. SAMPLING 5.1 A production lot shall be considered as a truckload or shipping container full of 1,500 lb boxes of resin, or one compartment of a railcar. The weights normally fall between 40,000 and 50,000 lb. 5.2 A truckload shall be sampled by obtaining 0.5 lb of material from each of eight boxes, for a total of 4 lb of resin. Combine the eight samples to form a lot sample. 5.3 A compartment of a railcar shall be sampled by obtaining 2 lb from the top and 2 lb from the bottom of the compartment. Combine the two samples to form a lot sample. 5.4 The entire lot sample shall be dry blended before sample preparation. A convenient way to do this is by hand in a 5-gallon plastic pail. 5.5 Divide the lot sample into two; one for immediate testing and the other for validation testing, should the need arise. The back-up sample shall be kept for 90 days after the resin is sold. 5.6 Clearly label the sample and include a traceable production number and a date. ______________________________________________________________________ 6. SAMPLE PREPARATION 6.1 Homogenize about 2 lb (900 g) of material by melt blending without filtration, preferably with a twin screw laboratory extruder. A two roll mill is also acceptable. 6.2 The blended material shall be compression molded according to ASTM D4703, with the use of a 15C/min cooling rate. 6.3 The plaque shall be 1.9- 0.08-mm (0.075- 0.003-in.) thick. 6.4 The plaque shall be allowed to equilibrate at standard laboratory conditions (72F, 50% RH) for at least 12 hours before tensile testing. ______________________________________________________________________ 7. TEST METHODS 7.1 Test Conditions Unless otherwise specified in the test methods or in this specification, conduct tests at the standard laboratory temperature of 23 2C (73.4 3.6F). 7.2 Density Test methods ASTM D1505 or D792 are acceptable. Make three separate determinations using separate homogenized pellets or separate

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E-5 portions of a plaque. The plaque thickness shall be 1.9 0.08 mm (0.075 .003 in.). Calculate and report the average and standard deviation from the mean. 7.3 Melt Index Test method ASTM D1238, using Condition 190/2.16. Make duplicate determinations on either pellets or a plaque and calculate the average. 7.4 % Volatiles This test will be performed in aluminum pans that have been heated at 350F (177 C) until they obtain a constant weight. 7.4.1 Test duplicate samples. 7.4.2 Weigh 2.000 0.100 g of pellets or a plaque to an accuracy of three places past the decimal point into an aluminum pan. 7.4.3 Place the pan in a forced-air recirculating oven preheated and stabilized to 350 5F (177 2C) for a period of 1 hour. 7.4.4 Remove the pan and let it completely cool to room temperature in a desiccator. 7.4.5 Reweigh the pan and calculate the percentage weight loss of the sample. Report the average to the nearest 0.01%. 7.5 % Ash - Test method ASTM D5630, Procedure B. 7.5.1 Sample size shall be 1g. 7.5.2 Heat at least 10 minutes at 800C. 7.5.3 Test in triplicate samples. 7.6 % Polypropylene 7.6.1 Generate a melting curve by differential scanning calorimetry (DSC) at a heating rate of 10C/min. See Figure 1. 7.6.2 The curve shall be expanded to a range that includes the end of the HDPE peak and the complete PP peak. See Figure 2. 7.6.3 Integrate the curve from a flat point before the PP melting to a point where the PP curve returns to baseline.

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E-6 0 -1 Heat Flow (W/g) -2 -3 -4 20 40 60 80 100 120 140 160 180 200 Exo Up Temperature (C) Universal V4.5A TA Instruments Figure 1. DSC curve of HDPE containing PP generated. 7.6.4 Mark the point where the HDPE melt returns to baseline. The end of the HDPE melt and the beginning of the PP melt will not necessarily be the same point. -0.56 150.59C -0.58 2.568J/g 142.71C -0.60 Heat Flow (W/g) -0.62 162.84C -0.64 -0.66 130 140 150 160 170 180 Exo Up Temperature (C) Universal V4.5A TA Instruments Figure 2. DSC curve of HDPE containing PP expanded. 7.6.5 Record the HDPE end-of-melt temperature and the PP heat of fusion in J/g. 7.6.6 Calculate the theoretical heat of fusion for 100% polypropylene for the portion of the PP melting curve that does not overlap with HDPE by:

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E-7 Y = -0.035X2 + 8.851X 475.6 (1) Where: X = HDPE end-of-melt temperature (C) And Y = Hf of 100% PP not overlapped with HDPE. For X = 142.7, Y = 74.7 J/g. 7.6.7 Calculate the percentage PP by: %PP = Hf sample/ Hf 100% PP x 100 (2) For Hf sample = 2.57 J/g, %PP = 3.4 % 7.6.8 Test two specimens from different parts of the molded plaque and report the average. 7.7 Yield Stress/Break Strain Test ASTM Method D638, with Type IV dumbbell, 2- in./min crosshead speed. 7.7.1 Test five specimens, individually measured for thickness. 7.7.2 Assume 1.3-in. gage for yield stress and 2.0-in. gage length for break strain. Use crosshead to follow displacement. 7.7.3 Report 5 results, average, and standard deviation. ______________________________________________________________________ 8. RETEST AND REJECTION 8.1 If any failure occurs, the material shall be retested to establish conformity in accordance to the specified property. A second failed result will result in rejection of the lot for the purposes of this specification. ______________________________________________________________________ 9. CERTIFICATION 9.1 Upon request of the purchaser in the contract or order, a manufacturer's certification that the material was manufactured and tested in accordance with this specification, together with a report of the test results, shall be furnished at the time of shipment.