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Is PVAL, PVA, or PVOH the real poly(vinyl alcohol)?

An educator has found a confusing array of abbreviated terms for common polymers published in the literature and proposes that all SPE authors and editors use the standard terminology in ASTM D 1600-92.

Yes, PVAL is the letter code for poly(vinyl alcohol) according to the ASTM. This is a great confession for me because for several years I have been using PVOH or even considering PVA for polyvinyl alcohol (the two different spellings for the spelled out words are both correct, depending upon which standards you are following).

As a teacher, I try not to confuse my students more than necessary. We already use the word gate to mean the door that covers the platen or mold hanging area in an injection molding machine as well as the entrance to the cavity in a mold. Can the words die, mold, and tool have the same meanings sometimes and different meanings at other times? With a plethora of ambiguous terms, it is amazing that students don't get more confused. What are the differences between PBT, PTP, TPES, PMTP, PTMT, and PBTP?

The Rest of the World

As if these were not bad enough, we can ask how our colleagues in Europe, Asia, or even Canada and Mexico name plastics with two-, three-, and four- or even five-letter terms. Right, they do it their way!

Authors, editors, and readers want their writings to be clear and understandable. How can the title be keyworded for computer retrieval if it contains the letters PVOH instead of the PVAL term used by ASTM? An author or editor who uses the letters POVH for poly(vinyl alcohol) might use the PVAL term for some other material and further add to the difficulty of retrieving the article and confusing the reader unnecessarily.

As a chemist myself, I blame much of the confusion on chemical nomenclature. The International Union of Pure and Applied Chemistry (IUPAC) issues publications on nomenclature that include polymers. The American Chemical Society (ACS) has a nomenclature database in Chemical Abstracts that is different from that used by IUPAC. Chemists still use the word acetone rather than propanone, dimethylketone, 2-propanone, or propanone-2 for a common solvent that many of us have used. Toluene, toluol, |C.sub.7~|H.sub.8~, and methylbenzene are all the same stuff but |C.sub.7~|H.sub.8~ can be a few other things as well! The ASTM's two-, three-, four-, and five-letter terms are intended as an everyday shorthand for the far more complex chemical nomenclature for polymers, and it is this terminology that is used by plastics engineers along with common names like acetone.

We Need Short Terms For Complex Substances

The world would be quite different for many of us if terms like ABS, LLDPE, SAN, and PTFE were taken from our vocabularies. We extend this shorthand into testing with terms like DSC, TGA, and DMA. We use the plasticizer DOP in PVC. But what happens when a sample containing the plasticizer DMA is to be tested by DMA? Yes, we do have the same letters for different things, as well as different letters for the same things! Computer programs using "fuzzy logic" or artificial intelligence (AI) cannot solve these problems of human language and communication. The solution is up to us. We are tired of being confused by POM and PMO meaning polyoxymethylene and polymethylene oxide (they are both polyacetal homopolymer!)

Since I undertook to raise this issue, I felt that I should attempt to offer some reasonable suggestions for SPE authors, editors, and readers to consider. (This assumes that SPE is not considered to be some new kind of Styrene PolyEthylene copolymer!) So I considered calling a few real experts on polymer and plastics nomenclature to get their input on this important issue. I began looking for these experts in some of the publications that I read.

Other Professional Groups Also Have Problems

In the March 22, 1993, issue of Chemical & Engineering News (C&EN), the ACS's weekly member magazine, an article describes an explosion in a polyvinyl alcohol (PVA) plant. In the March/April 1993 issue of Plastics Design Forum, ARCO Chemical published "A Guide to Plastics Acronyms." The terms PVA and PVAL are both listed for polyvinyl alcohol. PBT is used for something called Polybutadiene terephthalate, and PTMT is used for Polytetramethylene terephthalate. The ASTM nomenclature uses PBT for Poly(butylene terephthalate) and mentions the terms TPES (ThermoPlastic polyESter general) as the general term for this broad class of polymers.

MRS Bulletin, March 1993, has an article on the use of PVA (polyvinyl alcohol acetate) to produce macro-defect-free cement composite. The article also uses the letters pva in two graphs and PVA in a third graph. By the way, this is an interesting use of organic polymers to increase the strength of an inorganic material.

Did looking for expert advice in recent publications help me or confuse me? Did each publication seem to have a different system? Does anyone agree on these acronyms?

Finding an Expert

L.H. Sperling of Lehigh University and W. V. Metanomski of Chemical Abstract Services recently wrote a short paper, "Nomenclature in Polymer Science and Engineering," which appeared in the Proceedings of the American Chemical Society Division of Polymeric Materials: Science and Engineering, for the 1993 Spring Meeting of ACS in Denver. The paper covers matters of nomenclature that are far more complex than the everyday type used by SPE, so I felt that this would be a good source for guidance on simple (but precise) acronyms.

On March 25, 1993, I contacted W. V. Metanomski, an expert who keeps track of articles on nomenclature. He noted that Chemical Abstracts does not use acronyms in their indexing. IUPAC does use abbreviated terms(1,2) and so does the ACS Division of Polymer Chemistry(3). He has been working with ISO (International Standards Organization) as well as ASTM, editors of ACS publications, and many others for standards. He was most complimentary about SPE Editor Dr. Roger S. Porter, who has published nomenclature standards and requires authors to define any abbreviations for substances or methods in PE&S and PC (SPE journals of record). Bob Braddicks, editor of JVT, has a similar policy. Metanomski realizes that there will be errors in use, so he supports Porter's and Braddicks's editorial policies of requiring authors to define terms.

So Where Does All This Leave Us?

SPE authors, editors, indexes, technical program chairpersons, ANTEC and RETEC papers, etc., should continue their support for ISO and ASTM nomenclature (ASTM follows ISO in this area, so they are the same). The ISO/ASTM polymer acronyms are listed below, copyright ASTM, reprinted with the kind permission of the ASTM.

Next, SPE should support the work of ISO, ASTM, ACS, IUPAC, etc., in reaching worldwide nomenclature standards. Finally, since nomenclature is dynamic, authors of all SPE-related publications should define their nomenclature terms if they are non-standard.


1. IUPAC, "Compendium of Macromolecular Nomenclature," W. V. Metanomski, ed., Blackwell Scientific Publications, Oxford (1991). Available in the U.S. from CRC Press, Boca Raton, Fla.

2. IUPAC, "Use of Abbreviations for Names for Polymeric Substances," Pure and Appl. Chem., 59, 691 (1987); reprinted as Chapter 9 in Ref. 1.

3. Nomenclature Committee, ACS Division of Polymer Chemistry, "Abbreviations for Thermoplastics, Thermosets, Fibers, Elastomers, and Additives," Polym. News, 9, 101 (1983); 10, 169 (1985).

Other general references of interest:

4. ASTM D-1600.

5. H. Saechtling, International Plastics Handbook, Hanser (1983).

6. J.-M. Charrier, Polymeric Materials and Processing, Hanser (1990).

Ernest A. Coleman is consultant who serves SPE as a member of both the Publications and Technical Volumes Committees.
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Title Annotation:Nomenclature; confusion on abbreviated chemical terms
Author:Coleman, Ernest A.
Publication:Plastics Engineering
Date:Jun 1, 1993
Previous Article:1993 additives annual.
Next Article:Plastics Additives: An Industrial Guide, 2d ed.

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