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11.3.7 Miscellaneous data

This category typically includes nonstandard or application-specific properties such as environmental effects on properties of plastics.

Targeted application Industry focus Material property
Components involving Lawn and garden UV stability
outdoor or UV exposure Automotive exterior Gasoline resistance
Automotive interior Fogging resistance
(above belt line)
Food containers Packaging Gas barrier
Disposable components Healthcare Autoclaveability
Radiation sterilizability
Enclosures for electronic units Information technology Electromagnetic
interference/radio
frequency (EMI/RF)
shielding effectiveness

The environmental effects are not routinely reported primarily because of the unique and complex nature of the surrounding envi- ronments associated with each application.

11.4 Test Methods for Acquisition and
Reporting of Property Data

For testing plastics, a wide spectrum of national standards have been practiced worldwide—for instance, American Society for Testing and Materials (ASTM) standards in the United States, Deutsches Institut für Normung (DIN) in Germany; British Standards Institution (BSI) standards in the United Kingdom, Association Française de Normalisation (AFNOR) standards in France, and Japanese Industrial Standards (JIS) in Japan (Fig. 11.2).
In theory, any of these national standards could achieve global acceptance. However, in reality, none of them is in contention for uni- versal acceptance worldwide because of each’s national identity.

Figure 11.2 Plastics test standards around the world.

Organization for Standardization (ISO), which have been derived and from those developed by ASTM, DIN, BSI, and others, have the great- est chance to provide the basis for consensus on single set of global standards. Test methods developed by International Electrotechnical Commission (IEC) fulfill a similar role where electrical properties are concerned.
Table 11.11 lists the test methods commonly employed for determin- ing the properties of plastics reported in datasheets.
For the design data, the relevant properties that need to be evalu- ated along with the applicable ISO and ASTM standard methods are summarized in Tables 11.12 and 11.13, respectively. For some of the properties like pvT data, no-flow temperature, ejection temperature, and fatigue in tension, etc., no national or international standards exist today. Efforts are under way to develop industrywide standards for these properties. Suggested test conditions in Tables 11.12 and
11.13 are intended to serve as a guide in establishing specific test con- ditions for the purpose of developing comparable data.

TABLE 11.11 Key Properties of Plastics Reported in Datasheets and Common Test
Methods
Test method in accordance with

Property ISO methods ASTM methods

Specific gravity/density ISO 1183 D 792
D1505 (polyolefins)
Water absorption ISO 62 D 570
Melt flow rate (MFR) ISO 1133 D 1238
Mold shrinkage ISO 294-4 (thermoplastics) D 955
ISO 2577 (thermosets)
Tensile properties ISO 527-1 and 2 D 638
Flexural properties ISO 178 D 790
Notched Izod impact strength ISO 180 D 256
Instrumented dart impact strength ISO 6603-2 D 3763
Deflection temperatures under load ISO 75-1 and 2 D 648
Vicat softening temperature ISO 306 D 1525
Coefficient of thermal expansion ISO 11359-2 E 831

application to another. It, therefore, is critical for the design engineer or material specifier to test plastics under actual conditions of use to determine the suitability of the plastic for the intended application.
ISO brings together the interests of producers, users, governments, and the scientific community in the development of standards which can be accepted as international standards by consensus among the participating countries. The scope of ISO covers standardization in all fields except electrical and electronics engineering, including some areas of telecommunications, which are the responsibility of IEC. The objective of ISO and IEC is to promote the standardization and relat- ed activities in the world to facilitate the international exchange of goods and services and to develop cooperation in the spheres of intel- lectual, scientific, technological, and economic activity.
ISO, founded in 1947 with headquarters in Geneva, Switzerland, is a worldwide federation of 110 national standards bodies, represented, at present, by one “official” member for each participating country. A member body of ISO is the national body “most representative of stan- dardization in its country.” The American National Standards Institute (ANSI) is the U.S. member body. ISO has about 200 estab- lished technical committees (TC) to address specific areas; the techni- cal committee which represents the field of plastics and semifinished plastic products is TC61 on Plastics. ISO TC61 currently has 26 par- ticipating (P) member bodies (Table 11.14). In addition, there are 42 observer (O) member bodies. IEC, founded in 1906, is now comprised of about 50 national electrotechnical committees.

D 695 At 23°C, at least three elevated temperatures, and one temperature below standard laboratory conditions at standard strain rate; at three additional strain rates at 23°C. At 23°C, at least one elevated temperature, and one temperature below standard laboratory conditions.
At 23°C, two additional elevated
temperatures, and one
temperature below standard
laboratory conditions.
Shear modulus 6721-2, 5 D 5279 —150°C to Tg + 20°C or Tm +
10°C @ 1 Hz.
Creep in tension 899-1 D 2990 At 23°C and at least two
elevated temperatures for 1000 h
at three stress levels.
Fatigue in tension S — N curves at 3 Hz at 23°C;
80, 70, 60, 55, 50, and 40% of
tensile stress at yield; R = 0.5; 1
million cycles run out.
a — N curves at 3 Hz at 23°C;
single edge notched specimens;
three stress levels; R = 0.5.
Coefficient of friction 8295 D 3028 At 23°C against itself and steel.
Application-specific:
Creep in bending 899-2 D 2990 At 23°C and at least two
elevated temperatures for 1000 h
and at least three stress levels.
Creep in compression D 2990 At 23°C and at least two
elevated temperatures for 1000
h and at least three stress
levels.
Fatigue in bending* At 23°C; fully reversed; 80, 70,
60, 55, 50, and 40% of tensile
stress at yield @ 3 Hz.
Fracture toughness 13586-1 D 5045
*No ASTM or ISO standard exists today.
†Although the test frequency is restricted to 30 Hz only, D 671 may, in principle, be used.

TABLE 11.13 Material Property Characterizations for Processing Simulations
Test Method

ISO ASTM Suggested conditions
Melt viscosity–
shear rate data 11443 D 3835 At three temperatures, over shear rate range 10–10000 s—1
Reactive viscosity 6721-10 A slit die rheometer
of thermosets according to ISO 11443 can also be used.
Uniaxial
extensional viscosity* Biaxial
extensional viscosity* First normal

120, 160, and 200 MPa with an estimation at 1 MPa.
Thermal conductivity D 5930 23°C to processing temperature. Specific heat 11357-4 D 3418 DSC cooling scan @ 10°C/min from
processing temperature to 23°C. No-flow temperature* DSC cooling scan @ 10°C/min from
processing temperature to 23°C (11357-3). Ejection temperature* DSC cooling scan @ 10°C/min from
processing temperature to 23°C (11357-3).
Glass transition
temperature 11357-2 D 3418 DSC cooling scan @ 10°C/min from processing temperature to 23°C.
Crystallization
temperature 11357-3 D 3418 DSC cooling scan @ 10°C/min from processing temperature to 23°C.
Degree of crystallinity 11357-3 D 3418 DSC cooling scan @ 10°C/min from processing temperature to 23°C.
Enthalpy of fusion 11357-3 D 3417 DSC heating scan @ 10°C/min from 23°C
to processing temperature.
Enthalpy of
crystallization 11357-3 D 3417 Cooling scan @ 10, 50, 100, and
200°C/min from processing temperature to 23°C.
Crystallization 11357-7 D 3417 Isothermal scans at different cooling kinetics rates at three temperatures in the
crystallization range.
Heat of reaction
of thermosets 11357-5 D 4473 Heating scan @ 10°C/min from 23°C to reaction temperature.
Reaction kinetics
of thermosets 11357-5 D 4473 Isothermal DSC runs at three temperatures in the reaction temperature range.
Gelation conversion 11357-5 Heating scan @ 10°C/min. Isothermal induction
time
Coefficient of linear
thermal expansion 11359-2 E 831 With specimens cut from ISO 294-3 plate
over the range —40 to 100°C.
Mold shrinkage:
Thermoplastics 294-4 D 955 At 1, 1.5, and 2 mm thickness with cavity
Thermosets 2577 pressures of 25, 50, 75, and 100 MPa.
In-plane shear
modulus 6721-2 or 7
*No ASTM or ISO standard exists today.

TABLE 11.14 Participating (P) Members of ISO TC61 on Plastics

Country National standards osrganization

Belgium Institut Belge de Normalisation (IBN) Canada Standards Council of Canada (SCC)
People’s Republic China State Bureau of Technical Supervision (CSBTS)
of China
Colombia Instituto Colombiano de Normas Técnicas (ICONTEC) Czech Republic Czech Office for Standards, Metrology
and Testing (COSMT)
Finland Finnish Standards Association (SFS)
France Association Française de Normalisation (AFNOR) Germany Deutsches Institut für Normung (DIN)
Hungary Magyar Szabványügyi Hivatal (MSZH) India Bureau of Indian Standards (BIS) Islamic Republic Institute of Standards and
of Iran Industrial Research of Iran (ISIRI)
Italy Ente Nazionale Italiano di Unificazione (UNI) Japan Japanese Industrial Standards Committee (JISC) Republic of Korea Korean Industrial Advancement
Administration (KIAA)
Netherlands Nederlands Normalisatie-Instituut (NNI) Philippines Bureau of Product Standards (BPS)
Poland Polish Committee for Standardization (PKN) Romania Institutul Roman de Standardizare (RS) Russian Committee of the Russian
Federation Federation for Standardization, Metrology and Certification (GOST R)
Slovakia Slovak Office of Standards, Metrology and Testing (UNMS)
Spain Associación Espanola de
Normalización y Certificación (AENOR) Sweden Standardiseringen i Sverige (SIS) Switzerland Schweizerische Normen-Vereinigung (SNV) United Kingdom British Standards Institution (BSI)
United States American National Standards Institute (ANSI)

11.4.1 Impact of globalization

The elimination of trade barriers around the world through negotia- tions among countries involved in major international trade accords, such as the World Trade Organization (WTO), General Agreement on Tariffs and Trade (GATT), North American Free Trade Agreement (NAFTA), the European Union (EU), Asia Pacific Economic Cooperation (APEC), and MERCOSUR, etc., is changing the world into a single—global—marketplace. This trend has provided a new mean- ing to the term “globalization.” While some OEMs have seized this opportunity to establish a strong global presence, other OEMs have streamlined their product development process by relying on global sourcing and leveraging of resources across the continents. Business leaders around the globe have come to recognize the strategic impor- tance of international standards and their implications in world trade to efficiently design, manufacture, and deliver the same products to virtually any location in the world and the competitive disadvantage unless the industry adapts to the wave of global changes.
In the European Union (EU) and most other European nations, ISO/IEC test methods, where they exist, are being adopted as common European standards by the Committee for European Normalization (CEN) and the Committee for European Normalization of Electrotechnical testing (CENELEC). All major European standards organizations, such as DIN, BSI, and AFNOR, are accepting these inter- national standards as their national standards conforming to the Vienna Agreement between ISO and Committee for European Normalization (CEN). The Japan Plastics Industry Federation (JPIF) is involved in an aggressive 3-year project to bring Japanese industrial standards into compliance with ISO/IEC standards. This project is in response to the decision by the Japanese government to accelerate the compliance plan to demonstrate its commitment to the deregulation policy. Japan’s seri- ous commitment to convert to ISO/IEC test methods is underlined by its aggressive goal of completing the adoption of ISO/IEC standards for plas- tics by 2001. Most industrialized countries around the world have also adopted these universal standards outright or are using them as the basis for national standards.
In the United States, in order to achieve greater uniformity in their operations worldwide and to stay competitive in a global economy, the Big Three U.S. automakers have jointly instituted a strategic standardization initiative to develop plastics material specifications, based on ISO methodology, through the U.S. Council for Automotive Research (USCAR) consortium. The recently published Society for Automotive Engineers (SAE) specifications J16398 for nylon, and J16859 for ABS and ABS + PC, are the first two in a series of documents that are being adopted by the Big Three automakers. Currently in development are 10 new SAE speci- fications (Table 11.15).
The implication of this commitment from the Big Three automak- ers is that anyone supplying materials to the automotive industry will be required to report data based on ISO methodology as defined in the new SAE protocols in the very near future. A significant impact of this strategic move by the automotive industry is the dri- ve to switching from current practices based on ASTM test methods to uniform global testing protocols based on ISO test standards. One can expect that most of the engineering thermoplastics (ETP) and polypropylene (PP) producers will be routinely reporting only ISO test data.

TABLE 11.15 SAE Material Specifications Currently in Development

SAE
Standard Title

J 1686 Classification System for Automotive Polypropylene (PP) Plastics10
J 1687 Classification System for Automotive Thermoplastics Elastomeric Olefins (TEO)11
J 2250 Classification System for Automotive Poly(Methyl methacrylate) (PMMA) Plastics12
J 2273 Classification System for Automotive Polyester Plastics13
J 2274 Classification System for Automotive Acetal (POM) Plastics14
J 2323 Classification System for Automotive Polycarbonate Plastics15
J 2324 Classification System for Automotive Polyethylene Plastics16
J 2325 Classification System for Automotive Poly(Phenylene ether) (PPE) Plastics17
J 2326 Classification System for Automotive S/MA (Styrene-Maleic Anhydride) Plastics18
J 2460 Classification System for Automotive Thermoplastic Elastomeric Polyesters19

OEMs in the computer and business machines, appliance, health- care, and electronics industries and multinationals, who prefer to reduce the amount of resources and effort allocated for dual testing (separate testing by ISO/IEC and ASTM standards), are indicating an interest in ISO test methods. Xerox Corporation has already institut- ed multinational material specifications based on ISO/IEC test meth- ods. Even the U.S. government, particularly the U.S. Department of Commerce, continues to encourage adoption of ISO test methods. The U.S. government’s standards policy to encourage the development of standards in recognized organizations, such as ISO and IEC, and the subsequent use of these standards in the United States has not changed.
In late 1992, The Society of the Plastics Industry, Inc (SPI)’s Polymeric Material Producers Division (PMPD) recommended that its member companies begin to convert to the use of internationally accepted standards developed by ISO and IEC for determining the properties of plastics and to routinely supply data on product datasheets and advertisements, using the preferred ISO/IEC stan- dards, by June 1994. This strategic move was in response to the grow- ing needs of various market sectors, led by the automotive industry.
SPI recognized the considerable amount of confusion created by the conflicting messages and general misinformation that appeared in trade literature. In November 1993, SPI formed an ad hoc ISO Communications Committee under the auspices of the International Technical and Standards Advisory Committee (ITSAC), to provide a formal, coordinated response that adequately represents the interests of the resin producers and customers within the U.S. plastics industry. The main charter of this committee is to help SPI lead an industrywide effort to promote and educate the U.S. plastics industry on those issues surrounding the implementation of ISO/IEC test standards in accordance with the 1992 resolution.

During NPE ‘94, the ISO committee organized an industry forum with a roundtable panel discussion and issued a call for uniform glob- al testing standards for resins.*20 In early 1996, the committee also developed a Technical Primer21 illustrating the similarities and differ- ences between the ISO/IEC test methods and current U.S. practices.* This detailed primer targeted at the technical community also describes the essential steps involved in the conversion to ISO/IEC test methods. By mid-1996, the committee developed a Management Primer22 to promote the benefits of converting to uniform global test- ing standards for the U.S. industry leaders.*

11.4.2 Need for uniform global standards in testing plastics

Access to reliable and, most importantly, comparable property data is essential in material selection for any application, without which any attempt to compare properties among similar resins from different suppliers or from different sources, is apt to become an exercise in futility. This is primarily due to the fact that search for the most like- ly candidates invariably involves screening among available grades in the market on the basis of the properties that are related to the end- use performance requirements of the application.
At the outset, this appears straightforward and quite simple. Unfortunately, however, the material selection process often turns out to be an ordeal for anyone involved in this exercise. This is large- ly attributed to a combination of factors such as inconsistent test methods, different test specimen geometry as well as specimen molding conditions, flexibility in the choice of test conditions, and also lack of uniform reporting format associated with the current practices.23–25 The wide latitude for variability allowed today in spec- imen preparation and test conditions in data acquisition makes it difficult to meaningfully compare resin properties from different suppliers and even from various global manufacturing sites of the same supplier. The published deflection temperature under load (DTUL) of several ABS grades in Table 11.16 best demonstrates the variability arising from using specimens of varying thickness, dif- ferent specimen preparation methods, and pretreatment, if any. If one is only focusing on the DTUL value, ignoring these important variables, the result could be disastrous. Similarly, multiple test standards often employed to determine the impact behavior (Table
11.17) add further confusion.

*Copies may be obtained from The Society of The Plastics Industry, Inc., 1801 K Street, N. W., Suite 600, Washington, D.C. 20005.

With more than 15,000 grades of resins to choose from in the United States alone, over 6000 grades in Europe, and nearly 10,000 grades in Japan, it is not difficult to appreciate the magnitude of this problem. It is further compounded by the fact that the data for many of the products often lacks sufficient information regarding test conditions, specimen details, etc., in commercial databases or even resin manu- facturers’ product literature.
Such lack of uniformity in the acquisition and data reporting, added to lot-to-lot variability and interlaboratory variations, contributes to more frustration among the material specifiers and designers. Adoption of uniform test standards on a global basis would alleviate this ordeal and facilitate true comparability, that is, an “apples-to- apples” comparison. The benefits of adopting one set of test standards worldwide are

TABLE 11.16 Comparison of Deflection Temperature under Load (DTUL) at 1.8 MPa for ABS Resins from Different Suppliers

Specimen thickness, mm Specimen preparation method

Annealed DTUL
@ 1.8 MPa,
°C
Supplier A 3.2 Injection-molded No 76
3.2 Injection-molded Yes 100
3.2 Compression-molded Yes 102
Supplier B 12.7 Injection-molded No 85
12.7 Injection-molded Yes 93
Supplier C 12.7 ? No 92
12.7 ? Yes 100
Supplier D ? ? ? 106

TABLE 11.17 Multiple Test Standards Employed in Reporting Impact Strengths of
Polypropylene (PP) Homopolymer

Test standard
Method
Specimen Notch form Impact strength
ISO 180/1A ISO 180/1R ISO 179-1/1A Izod Izod Charpy 80 × 10 × 4 mm
80 × 10 × 4 mm
80 × 10 × 4 mm V U V 6 kJ/m2
50 kJ/m2
8 kJ/m2
ISO 179-1/1U Charpy 80 × 10 × 4 mm U NB
ASTM D 256 Izod 63 × 12.7 × 3.2 mm V 0.5 ft•lb/in
ASTM D 4812 Cantilever
beam impact 63 × 12.7 × 3.2 mm U 1068 J/m
ASTM D 3029/G Gardner 50 mm in
diameter × 3.2 mm U <10 in•lb
ASTM D 3763 Instrumented 100 mm in U <2 ft•lb
dart impact diameter × 3.2 mm

NOTE: U = unnotched.

■ Long-term cost savings. Multinational companies stand to save costs in the long run from elimination of the need to retest or investing time and effort in comparing test methods.
■ Increased opportunities for access to international markets. Adoption of uniform global testing protocols equate to “speaking the same lan- guage with customers around the globe,” facilitating greater access to international markets that were not possible earlier.
■ Easier procurement of materials worldwide. In the growing global manufacturing environment, use of one set of universally accepted test standards would facilitate easier procurement of materials against uniform global specifications, regardless of where in the world they are manufactured or needed.
■ Greater consistency in data. The adoption of more stringent, consis- tent, and uniform methodology in generation of material property data by resin suppliers will reduce the large variability associated with the data prevalent today.
■ Improved communication. Communication between manufacturers and resin suppliers worldwide is expected to improve significantly by having comparable data. In the case of multinational companies, internal communication between their manufacturing sites around the world will be improved as well.

11.4.3 Uniform global testing protocols

In order to produce truly comparable data, use of uniform standards, uniform test specimens, standard molds, narrow specimen molding conditions specifically defined for each resin family, and uniform test conditions, that is, identical, reproducible conditions is vital. Simply providing detailed information about the specimen geometry, prepara- tion, conditioning, and test procedure is not sufficient to allow true comparability.
Until recently, the lack of uniform testing protocols for plastics posed a major hurdle. Fortunately, three international standards—ISO
10350-1,26 ISO 11403-1,27 and ISO 11403-228—were specifically devel- oped by an international collaborative effort to address these issues. ISO 10350-1 forms the basic framework for testing and reporting of single-point data on plastics by designating specific test procedures and conditions that are specified in other ISO test standards, and when used in conjunction with the relevant ISO material standards, it defines rigid guidelines for the choice of specimen geometry, mold design, specimen preparation conditions, and test conditions. ISO
10350-1 clearly indicates which test specimens should be used for each test and how the specimens should be prepared. For example, to determine the tensile modulus of an ABS resin, ISO 10350-1 specifies using the 4-mm-thick, ISO 316729 multipurpose specimen, molded using the balanced mold design with gating as specified in ISO 294-130 at conditions specified in the ABS material document ISO 2580-2,31 and tested according to the procedures described in ISO 527-232 at a speci- fied test speed of 1 mm/min. The end result of such a comprehensive approach is a reduction in variables associated with testing, which yields more reliable, reproducible, and, above all, comparable data. The test methods recommended in ISO 10350-1 are shown in Table 11.18.
To complement these “single-point” data with data representing the time- and temperature-dependent behavior of plastics useful in product design, a similar document has been developed which deals with the acquisition and presentation of comparable multipoint data. It has three parts: ISO 11403 -1 which deals with mechanical properties; ISO 11403-
2, which addresses the thermal and processing properties; and ISO
11403-3,33 which focuses on environmental influences on properties. Similar to ISO 10350-1, the multipoint data standards ISO 11403-1 and
-2 also define the types of specimens for testing, how the tests should be conducted, and provide a technically sound framework for acquisition of multipoint data.

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