1、Designation: D7711 111Standard Guide forDescription of Polymer Pellet Defects1This standard is issued under the fixed designation D7711; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parenth
2、eses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1NOTETitle was editorially corrected in October 2011.1. Scope1.1 This guide is a compilation of terms used to describedefects of polymeric pellets. Terms that are g
3、enerally under-stood or defined adequately in Terminology D883 or in otherreadily 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 notalways apply to translucent or opaque pellets.1.3 This standard d
4、oes not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.NOTE 1There is no known ISO equiva
5、lent to this guide.2. Referenced Documents2.1 ASTM Standards:2D883 Terminology Relating to Plastics3. Terminology and Definitions3.1 Pellet Color Defects and Terms:NOTE 2Not all color defect terminology is applicable to all pellettypes.3.1.1 discoloration, nof a pellet, any deviation from theproduct
6、s normal color.3.1.2 opaque center pellet, npellet that is translucent orslightly translucent and has a less clear/more opaque center bycomparison to the remainder of the pellet.3.1.3 striped pellet, npellet containing a stripe of adifferent color than the remainder of the pellet.3.2 Pellet Contamin
7、ation Defects and Terms:3.2.1 die pearls, nnon-degraded particles that build upand break off of the die.3.2.2 droolssee die pearls3.2.3 fines, nvery small particles, dust, or unattachedtails.3.2.4 foreign material contamination, nof pellets, anymaterial in, on, or around the pellets that emanates fr
8、om anexternal source and has a composition different than that of thepellet; also known as trash if it can be picked up separately.3.2.5 oxidized pellet, npellet with a deep yellow, brown,red, or black particle present.3.2.6 polymer cross-contamination, nof pellets, unin-tentional mixture of two or
9、more dissimilar resins or com-pounds; generally apparent by comparing key properties suchas pellet geometry, color, opacity, or hardness.3.2.7 speck contamination on/in, nof a pellet, smallpinpoint particles of discolored matter, internal or external,which can sometimes rub off; includes, but is not
10、 limited to:black, brown, yellow, or white specks.3.3 Pellet Size and Shape Defects and Terms:NOTE 3Polymeric pellets are of many shapes. These include cylinders(formed by a strand pelletizer), spheres (underwater-face cut), andsliver-like pieces (hot-face cut).3.3.1 agglomerates, nof pellets, thoro
11、ughly fused accu-mulation of pellets.3.3.2 angel hair, nthin, fiber or thread-like strands ofpolymer.3.3.3 clumpssee agglomerates3.3.4 clusters, nof pellets, three or more pellets fusedtogether; only referred to as triples when there are three distinctpellets.3.3.5 daisy chains, nof pellets, two or
12、more pellets joinedtogether “chain-like” by strands of polymer; can be separatedto form pellets with tails.1This guide is under the jurisdiction of ASTM Committee D20 on Plastics andis the direct responsibility of Subcommittee D20.92 on Terminology.Current edition approved Sept. 1, 2011. Published O
13、ctober 2011. DOI:10.1520/D7711-11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM Internation
14、al, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.3.6 doublessee marriages3.3.7 globssee agglomerates3.3.8 marriages, nof pellets, two pellets fused together.3.3.9 pellet non-uniformity, npellets that deviate fromnormal size-range and shape; for example, under
15、sized oroversized, over-length, not round, flattened on one or bothends, or smashed.3.3.10 snake skins, nlong, thin, film-like pieces of poly-mer, or a build-up that looks like a shed snake skin when itcomes free.3.3.11 streamerssee snake skins3.3.12 tail, non a pellet, a small thin extension attach
16、ed toa pellet; usually exceeds half the length of a normal pellet.3.3.13 triplessee clusters3.3.14 twinssee marriages3.3.15 walnutssee agglomerates3.4 Pellet Integrity Defects and Terms:3.4.1 cracks, nin a pellet, breaks, splits, or separationswithin the pellet that are visible to the unaided eye.3.
17、4.2 foamed pellet, npellet that contain voids due toentrapped water, volatiles, or other substances; typically whitein appearance and sometimes larger than normal-sized pellets.3.4.3 foamy pellet, nsee foamed pellet3.4.4 puffy pellet, nsee foamed pellet4. Significance and Use4.1 This guide is intend
18、ed to provide terminology for bothsuppliers and users of polymer pellets to ensure mutualunderstanding in discussions concerning pellet defects. It is notan absolute standard but is to be referred to when issues withthe quality and/or description of the polymeric materials arise.4.2 The guide is cat
19、egorized according to the best fit for theterm and its description for ease of finding certain descriptiontypes.4.3 Some terms within this guide do not apply to all resintypes. It is the users responsibility to determine if the term andits subsequent definition are applicable to the material inquest
20、ion.4.4 Other terminology relating to polymers that are notincluded in this document can be found in additional standardssuch as Terminology D883.5. Keywords5.1 color; contamination; defect; geometry; integrity; pel-let; shape; sizeASTM International takes no position respecting the validity of any
21、patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revis
22、ion at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your c
23、omments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrig
24、hted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).D7711 1112
