ASTM D7711-11

Standard Guide for Description of Polymer Pellets Including Defects

SIGNIFICANCE AND USE
This guide is intended to provide terminology for both suppliers and users of polymer pellets to ensure mutual understanding in discussions concerning pellet defects. It is not an absolute standard but is to be referred to when issues with the quality and/or description of the polymeric materials arise.
The guide is categorized according to the best fit for the term and its description for ease of finding certain description types.
Some terms within this guide do not apply to all resin types. It is the user’s responsibility to determine if the term and its subsequent definition are applicable to the material in question.
Other terminology relating to polymers that are not included in this document can be found in additional standards such as Terminology D883.
SCOPE
1.1 This guide is a compilation of terms used to describe defects of polymeric pellets. Terms that are generally understood or defined adequately in Terminology D883 or in other readily available sources are not included.
1.2 Not every term is applicable to every type of pellet. Terms which apply to transparent pellets, for example, do not always apply to translucent or opaque pellets.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
Note 1—There is no known ISO equivalent to this guide.

General Information

• Status: Historical
• Publication Date: 31-Aug-2011
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.92 - Terminology

Relations

• Replaced By: ASTM D7711-11e1 - Standard Guide for Description of Polymer Pellet Defects
• Effective Date: 01-Sep-2011

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:D7711–11
Standard Guide for
Description of Polymer Pellets Including Defects
This standard is issued under the fixed designation D7711; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 3.2.4 foreign material contamination, n—of pellets, any
material in, on, or around the pellets that emanates from an
1.1 This guide is a compilation of terms used to describe
external source and has a composition different than that of the
defects of polymeric pellets. Terms that are generally under-
pellet; also known as trash if it can be picked up separately.
stood or defined adequately in Terminology D883 or in other
3.2.5 oxidized pellet, n—pellet with a deep yellow, brown,
readily available sources are not included.
red, or black particle present.
1.2 Not every term is applicable to every type of pellet.
3.2.6 polymer cross-contamination, n—of pellets, unin-
Terms which apply to transparent pellets, for example, do not
tentional mixture of two or more dissimilar resins or com-
always apply to translucent or opaque pellets.
pounds; generally apparent by comparing key properties such
1.3 This standard does not purport to address all of the
as pellet geometry, color, opacity, or hardness.
safety concerns, if any, associated with its use. It is the
3.2.7 speck contamination on/in, n—of a pellet, small
responsibility of the user of this standard to establish appro-
pinpoint particles of discolored matter, internal or external,
priate safety and health practices and determine the applica-
which can sometimes rub off; includes, but is not limited to:
bility of regulatory limitations prior to use.
black, brown, yellow, or white specks.
NOTE 1—There is no known ISO equivalent to this guide.
3.3 Pellet Size and Shape Defects and Terms:
2. Referenced Documents
NOTE 3—Polymericpelletsareofmanyshapes.Theseincludecylinders
2 (formed by a strand pelletizer), spheres (underwater-face cut), and
2.1 ASTM Standards:
sliver-like pieces (hot-face cut).
D883 Terminology Relating to Plastics
3.3.1 agglomerates, n—of pellets, thoroughly fused accu-
3. Terminology and Definitions
mulation of pellets.
3.3.2 angel hair, n—thin, fiber or thread-like strands of
3.1 Pellet Color Defects and Terms:
polymer.
NOTE 2—Not all color defect terminology is applicable to all pellet
3.3.3 clumps—see agglomerates
types.
3.3.4 clusters, n—of pellets, three or more pellets fused
3.1.1 discoloration, n—of a pellet, any deviation from the
together; only referred to as triples when there are three distinct
product’s normal color.
pellets.
3.1.2 opaque center pellet, n—pellet that is translucent or
3.3.5 daisy chains, n—of pellets, two or more pellets joined
slightly translucent and has a less clear/more opaque center by
together “chain-like” by strands of polymer; can be separated
comparison to the remainder of the pellet.
to form pellets with tails.
3.1.3 striped pellet, n—pellet containing a stripe of a
3.3.6 doubles—see marriages
different color than the remainder of the pellet.
3.3.7 globs—see agglomerates
3.2 Pellet Contamination Defects and Terms:
3.3.8 marriages, n—of pellets, two pellets fused together.
3.2.1 die pearls, n—non-degraded particles that build up
3.3.9 pellet non-uniformity, n—pellets that deviate from
and break off of the die.
normal size-range and shape; for example, undersized or
3.2.2 drools—see die pearls
oversized, over-length, not round, flattened on one or both
3.2.3 fines, n—very small particles, dust, o
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