Best Practices in PET Recycling

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Clear PET Pellet Specifications for

Bottles, Sheet, and Engineered Resins

Issue: Successful conversion of recycled PET into end products requires a high quality resin that meets demanding product specifications and strict processing requirements, consistent and cost-effective manufacturing. Suppliers of post-consumer clean PET can sell into major PET applications only if the product meets customer specifications.

Background: The goal of this effort is to establish a level of industry consensus on post-consumer, clean regrind specifications. While this set of target quality specifications may be acceptable to most PET end-users, it is incumbent upon suppliers to determine unique or different specifications that their customers require.

To develop this set of quality specifications, a list of proposed specifications for post-consumer PET was sent to end-users who manufacture a variety of industrial and consumer products and applications, including: Bottles, Sheet and Film, and Engineered Resins. Each end-user modified the proposed specifications to reflect quality standards that suppliers must meet. Quality test methods are shown as "internal" when this information was not provided.

Best Practices: These post-consumer clean PET pellet specifications are not intended to meet any one company's individual specifications. They do, however, represent a standard that will be acceptable to most PET purchasers and a quality target that can reduce the cost of the PET recycling process. End-product manufacturers may identify specific variations that are required by their process or end-product.

As a general rule, higher valued applications have more stringent specifications for post-consumer clean PET pellet. This is particularly true for Intrinsic Viscosity, particulate contaminants, and PVC. The contaminants listed in the specifications are the only impurities permitted. By their omission, other contaminants are deemed unacceptable at any level. Ranges of contaminants are provided to allow for requirements of different end-product manufacturers in the same industry.

Benefits: These specifications are compiled by cooperation from industrial purchasers of recycled PET. Production of clear recycled PET regrind that meets the above standard specifications will increase the marketability of clean regrind.

Issue Date / Update: January 1998

CLEAR PET PELLETS – BOTTLE SPECIFICATIONS

Property	Specification	Test Method
Intrinsic Viscosity (dL/gm)	0.70 - 0.72 min	ASTM D4603
Particle Size (inch)	0.1 cube	Internal
Bulk Density (lbs/ft^3)	50 - 55	ASTM D1895
Moisture Content (%)	< 0.5	Internal
Color	L > 73 b < 3.0	Hunter Scale
Maximum Contaminant Levels (ppm):
Aluminum	0	Internal
Acetaldehyde	3	Internal
Labels	0	Internal
Low Melts	5	Internal
PVC	0-10	Internal
EVOH	10	Internal
PP/HDPE	0	Internal
Residual Glue	20-100	Internal
Green	100	Internal

CLEAR PET PELLET – SHEET SPECIFICATIONS

Property	Specification	Test Method
Intrinsic Viscosity (dL/gm)	0.66 - 0.67 min	ASTM D4603
Particle Size (inch)	1/8 cylinder or 0.1 cube	ASTM E11 or internal
Bulk Density (lbs/ft^3)	50 - 55	ASTM D1895 or internal
Moisture Content (%)	< 0.5	Internal
Color	L > 70 b < 3.0	Hunter
Maximum Contaminant Levels (ppm):
Aluminum	0	Internal
Labels	0	Internal
Low Melts	5	Internal
PVC	10	Internal
EVOH	10	Internal
PP/HDPE	Nil	Internal
Residual Glue	100	Internal
Green	50 - 250	Internal

CLEAR PET PELLET

ENGINEERED RESINS SPECIFICATIONS

Property	Specification	Test Method
Intrinsic Viscosity, dL/gm	0.65 – 0.80	ASTM D4603
Particle Size, inch	1/8 cylinder or 0.1 cube	ASTM E11 or internal
Bulk Density, lbs/ft^3	50 - 55	ASTM D1895 or internal
Moisture Content, %	< 0.5	Internal
Color	YI = 4 - 16 L = 75 – 80 a = -1.2 to -2.4 b = 1.4 - 6.6	Hunter
Maximum Contaminant Levels (ppm):
Aluminum	0	Internal
Labels	0	Internal
Low Melts	0-5	Internal
PVC	0-100	Internal
EVOH	0-10	Internal
PP/HDPE	0	Internal
Residual Glue	100	Internal
Green	50-500	Internal