ASTM D7711-2011 0625 Standard Guide for Description of Polymer Pellets Including Defects.pdf

1、Designation: D7711 11Standard Guide forDescription of Polymer Pellets Including 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

2、in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide is a compilation of terms used to describedefects of polymeric pellets. Terms that are generally under-stood or defined adequately

3、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 does not purport to address all of thesafety

4、 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 equivalent to this guide.2. Referenced Documents2

5、.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 theproducts normal color.3.1.2 opaque center pellet,

6、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 Contamination Defects and Terms:3.2.1 die pearls, n

7、non-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 from anexternal source and has a composition

8、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 more dissimilar resins or com-pounds; gener

9、ally 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 limited to:black, brown, yellow, or white

10、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, thoroughly fused accu-mulation of pellets.3.3.2

11、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 more pellets joinedtogether “chain-like” by

12、 strands of polymer; can be separatedto form pellets with tails.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, undersized oroversized, over-

13、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 attached toa pellet; usually e

14、xceeds half the length of a normal pellet.3.3.13 triplessee clusters3.3.14 twinssee marriages1This 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 September 2011.

15、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 International, 100 Barr

16、Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.3.15 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.3.4.2 foamed pellet, npellet that contain vo

17、ids 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 intended to provide terminology for bothsupplier

18、s 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 categorized according to the best fit for the

19、term 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 inquestion.4.4 Other terminology relating to poly

20、mers 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 patent rights asserted in connection with

21、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 revision at any time by the responsible technic

22、al 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 comments will receive careful consideration

23、 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 copyrighted by ASTM International, 100 Barr Harbo

24、r 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 112