Third generation metallocene EPDMs.Synthetic elastomers have been a fertile field for polymer research for over 50 years. The specialty ethylene-propylenediene (EPDM EPDM Ethylene-Propylene-Diene-Monomer EPDM Enterprise Product Data Management EPDM Ethylene Propylene Dimonomer (industrial/commercial piping/plumbing components) EPDM Engineering Product Data Management ) and ethylene-propylene (EPM EPM equine protozoal myeloencephalitis. ) rubbers, in commercial production for over 35 years, are currently enjoying a relatively high growth rate (about 6% per year) due in part to their chemical resistance and high extendibility while retaining good physical properties. This wide range of formulation and performance capabilities allows these specialty elastomers to be utilized in a wide variety of market applications (refs. 1-3). The technology to produce these specialty elastomers, introduced during the 1960s (refs. 4 and 5), remained relatively stagnant stagnant /stag·nant/ (stag´nant) 1. motionless; not flowing or moving. 2. inactive; not developing or progressing. until the 1990s when significant change occurred in both catalyst and process technologies (refs. 6 and 7). The use and advantages of constrained con·strain tr.v. con·strained, con·strain·ing, con·strains 1. To compel by physical, moral, or circumstantial force; oblige: felt constrained to object. See Synonyms at force. 2. geometry catalyst (CGC CGC Canine Good Citizen (AKC Dog Title) CGC Commission Géologique du Canada (Geological Survey of Canada) CGC Confédération Générale des Cadres (French labor union) ) technology for the commercial production of EPDM and other ethylene-[alpha]-olefin copolymers in solution processes has been well documented (refs. 15 and 16). Gas-phase EPDM production has been further advanced by combining the proven CGC technology with the gas-phase process. Carbon black is an integral part of the gas-phase EPDM process. CGC gas-phase EPDM is characterized by its granular granular /gran·u·lar/ (gran´u-lar) made up of or marked by presence of granules or grains. gran·u·lar adj. 1. Composed or appearing to be composed of granules or grains. 2. form, low odor and fast mixing behavior without the limitations of previous Ziegler-Natta based gas-phase EPDMs. A new third generation metallocene EPDM product line based on these combined technologies was introduced to the marketplace in 2002 under the trade name Nordel MG hydrocarbon hydrocarbon (hī'drōkär`bən), any organic compound composed solely of the elements hydrogen and carbon. The hydrocarbons differ both in the total number of carbon and hydrogen atoms in their molecules and in the proportion of hydrogen rubbers (ref. 14). This article will concentrate on the key attribute of the base polymer consistency for this new third generation metallocene EPDM, as well as the uniformity of the granular products. Experimental Compositional analysis was determined via infrared analysis (FTIR FTIR Fourier Transform Infrared (spectroscopy) FTIR Frustrated Total Internal Reflection FTIR Fourier Transfer Ir ) according to according to prep. 1. As stated or indicated by; on the authority of: according to historians. 2. In keeping with: according to instructions. 3. ASTM ASTM abbr. American Society for Testing and Materials D3900 for ethylene ethylene (ĕth`əlēn') or ethene (ĕth`ēn), H2C=CH2, a gaseous unsaturated hydrocarbon. It is the simplest alkene. and propylene propylene /pro·pyl·ene/ (pro´pi-len) a gaseous hydrocarbon, CH3CHdbondCH2. propylene glycol a colorless viscous liquid used as a humectant and solvent in pharmaceutical preparations. , and ASTM D6047 for ENB. All results are reported in wt. % monomer monomer (mŏn`əmər): see polymer. monomer Molecule of any of a class of mostly organic compounds that can react with other molecules of the same or other compounds to form very large molecules (polymers). content. Product Mooney viscosity was determined according to ASTM D1646. Thermal characterization of the samples was obtained using a differential scanning calorimeter calorimeter: see calorimetry. calorimeter Device for measuring heat produced during a mechanical, electrical, or chemical reaction and for calculating the heat capacity of materials. (DSC (1) (Digital Signal Controller) A microcontroller and DSP combined on the same chip. It adds the interrupt-driven capabilities normally associated with a microcontroller to a DSP, which typically functions as a continuous process. See microcontroller and DSP. ) TA DSCQ DSCQ Double Stimulus Continuous Quality (assessment for image quality) 100 equipped with a refrigerated re·frig·er·ate tr.v. re·frig·er·at·ed, re·frig·er·at·ing, re·frig·er·ates 1. To cool or chill (a substance). 2. To preserve (food) by chilling. cooling accessory. Product rheological rhe·ol·o·gy n. The study of the deformation and flow of matter. rhe  o·log data were taken on a rubber process analyzer analyzer /ana·ly·zer/ (an´ah-li?zer)1. a Nicol prism attached to a polarizing apparatus which extinguishes the ray of light polarized by the polarizer. 2. at 15% strain and 160[degrees]C. Polymer molecular weight (mw) and molecular weight distributions (mwd) were determined via gel permeation chromatography Gel permeation chromatography (GPC) is a separation technique based on hydrodynamic volume (size in solution). Molecules are separated from one another based on differences in molecular size. This technique is often used for polymer molecular weight determination. at 140[degrees]C with tri-chloro-benzene as the solvent. Results and discussion General overview The commercially available portfolio of Insite technology catalysts has facilitated DuPont Dow's venture into gas phase EPDM. Extensive knowledge of the effects of variations in catalyst structure and process conditions has allowed production of predictable products with respect to molecular architecture, composition and molecular weight (refs. 9, 15 and 16). Key characteristics are very high catalyst activity, resulting in clean products with low residues, as well as consistency and predictability. The catalyst was effective in significantly minimizing odor, acidity acidity /acid·i·ty/ (-i-te) the quality of being acid; the power to unite with positively charged ions or with basic substances. a·cid·i·ty n. The state, quality, or degree of being acid. , ash residue and water absorption compared to previous generation gas-phase EPDM products made with a Zeigler-Natta catalyst (refs. 12 and 13). MG EPDM One distinguishing and useful characteristic of MG EPDM elastomers is their unique granular form. Typical average particle sizes Particle size, also called grain size, refers to the diameter of individual grains of sediment, or the lithified particles in clastic rocks. The term may also be applied to other granular materials. of the granules Granules Small packets of reactive chemicals stored within cells. Mentioned in: Allergic Rhinitis, Allergies are in the range of 1.0-1.5 mm. Gas-phase MG granules are coated with carbon black in the process which acts as a partitioning To divide a resource or application into smaller pieces. See partition, application partitioning and PDQ. agent to minimize polymer particle agglomeration ag·glom·er·a·tion n. 1. The act or process of gathering into a mass. 2. A confused or jumbled mass: . The carbon black used is a general-purpose high structure grade (N650-GPF-HS). This granular form is conducive to flexibility in material handling, rapid mixing and dispersion dispersion, in chemistry dispersion, in chemistry, mixture in which fine particles of one substance are scattered throughout another substance. A dispersion is classed as a suspension, colloid, or solution. , as well as single-pass (one-pass) batch mixing and continuous compounding Continuous Compounding The process of earning interest on top of interest. The interest is earned constantly, and immediately begins earning interest on itself. Notes: (ref. 10). The current product slate is shown in table 1. These unique granular products deliver excellent compound performance when utilized in large scale mixing equipment. However, there is a possibility that incorrect sampling procedures for small scale laboratory testing can lead to erratic er·rat·ic adj. 1. Having no fixed or regular course; wandering. 2. Lacking consistency, regularity, or uniformity: an erratic heartbeat. 3. results. These incorrect laboratory sampling procedures have led to erroneous erroneous adj. 1) in error, wrong. 2) not according to established law, particularly in a legal decision or court ruling. speculations of non-uniform polymer properties and/or lot-to-lot polymer inconsistency in·con·sis·ten·cy n. pl. in·con·sis·ten·cies 1. The state or quality of being inconsistent. 2. Something inconsistent: many inconsistencies in your proposal. . This article highlights the consistency and predictability of two of the current Insite technology catalyst derived MG products. NDR NDR Norddeutscher Rundfunk NDR non-delivery report (email) NDR Network Data Representation NDR National Driver Register NDR Non-Delivery Receipt (email) NDR Negative Differential Resistance 47085 EPDM Lot-to-lot uniformity and consistency The lot-to-lot polymer uniformity and consistency was examined by selecting every third lot from a 36-lot campaign of polymer produced in 2003. The intra-lot polymer consistency of one of these lots was also examined. Each selected lot was examined to determine the following polymer and product properties: Composition, molecular weight (mw), molecular weight distribution (mwd), product processability and carbon content. The lot designations are shown in table 2. The polymer compositional uniformity and product uniformity are shown in figures 1 and 2. [FIGURES 1-2 OMITTED] The polymer lot-to-lot mwd consistency is shown in figure 3. The GPC (1) A PC that uses the Linux-based gOS operating system. See gOS. (2) (GPC Group) Originally the Graphics Performance Characterization committee of the NCGA, the GPC Group is now part of Standard Performance Evaluation Corporation (SPEC) and oversees the following overlays demonstrate the very high uniformity and lot-to-lot polymer mwd, as well as mw consistency. [FUGRE 3 OMITTED] The product lot-to-lot rheological consistency is show in figure 4. This high lot-to-lot rheological uniformity and consistency is a result of the predictable polymer properties derived from the Insite technology catalyst and uniform lot-to-lot carbon content. [FIGURE 4 OMITTED] The overall very high lot-to-lot polymer and product uniformity and consistency are summarized in table 2. Intra-lot uniformity and consistency One distinguishing and useful characteristic of MG EPDM elastomers is their unique granular form. Typical average particle size of the granules is in the range of 1.0-1.5 mm. Gas-phase MG granules are coated with carbon black in the process, which acts as a partitioning agent to minimize polymer particle agglomeration. A single lot from this campaign was sieved into thirteen fractions and examined to determine the following polymer properties according to granular particle size: Composition, row, mwd and carbon content. The lot designation and sieve information are shown in table 3. The product particle distribution and weight percentage of each fraction for this set of 13 fractions are shown in figure 5. The polymer compositional uniformity between granular particle sizes is shown in figure 6. The high polymer particle-to-particle mwd consistency is shown in figure 7. The GPC overlays demonstrate the very high particle-to-particle polymer mwd, as well as mw consistency. [FIGURES 6-7 OMITTED] Figure 8 indicates where improper sampling techniques can lead to erratic laboratory results when a small "grab" sample is quickly taken for laboratory tests. There are several acceptable laboratory techniques Laboratory techniques are the sum of procedures used on natural sciences such as chemistry, biology, physics in order to conduct an experiment, all of them follow scientific method; while some of them involves the use of complex laboratory equipment from laboratory glassware to that can easily be employed to obtain a small representative granular sample for laboratory analysis (ref. 17). [FIGURE 8 OMITTED] The overall high granule-to-granule particle size polymer uniformity and consistency are summarized in table 3. NDR 37060 EPDM Lot-to-lot uniformity and consistency The lot-to-lot polymer uniformity and consistency was examined by selecting every third lot from a 36-lot campaign of polymer produced in 2003. Each selected lot was examined to determine the following polymer and product properties: composition, mw, mwd, product processability and carbon content. The lot designations are shown in table 4. The polymer compositional uniformity and product uniformity are shown in figures 9 and 10. The high polymer lot-to-lot mwd consistency is shown in figure 11. The GPC overlays again demonstrate the very high lot-to-lot uniformity of polymer mwd, as well as mw consistency. [FIGURE 9-11 OMITTED] The lot-to-lot rheological product consistency is show in figure 12. High lot-to-lot rheological uniformity and consistency are a result of the predictable polymer properties derived from the Insite technology catalyst and uniform lot-to-lot carbon content. The very high overall lot-to-lot polymer and product uniformity and consistency are summarized in table 4. Summary Nordel MG products exhibit excellent lot-to-lot polymer uniformity and consistency. Excellent lot-to-lot uniformity and consistency are a result of the predictable polymer properties derived from the Insite technology catalyst. These advances in process and catalyst technology have provideds commercially available gas-phase process EPDM that provide new possibilities for the rubber compounder and parts fabricator fab·ri·cate tr.v. fab·ri·cat·ed, fab·ri·cat·ing, fab·ri·cates 1. To make; create. 2. To construct by combining or assembling diverse, typically standardized parts: . The granular form allows for automated transportation and weighing. Following good and established practices for sampling granular or powdered material provides a good and accurate measure of product uniformity and consistency. Combined with the fast, high quality mixing performance, gas-phase EPDM can greatly improve manufacturing efficiency.
Table 1
MG product grades NDR NDR
Method 37060 47085
Characteristics
Polymer composition
Ethylene content, wt. % ASTM D 3900 68 69.5
Propylene content, wt. % ASTM D 3900 30 26
ENB content, wt. % ASTM D 6047 2.2 4.5
Base polymer *
Mooney viscosity,
ML 1+4 @ 125[degrees]C ASTM D 1646 * 60 * 85 *
N650 black content, phr DDE EPRG-2 30 30
Massed density, gm/ml ASTM D 297 0.99 0.99
Product form Granular Granular
MG product grades NDR NDR NDR
47100 47130 46140
Characteristics
Polymer composition
Ethylene content, wt. % 73 67.5 58
Propylene content, wt. % 22 28 37
ENB content, wt. % 4.9 4.9 4.9
Base polymer *
Mooney viscosity,
ML 1+4 @ 125[degrees]C 100 * 130 * 140 *
N650 black content, phr 30 30 30
Massed density, gm/ml 0.99 0.99 0.99
Product form Granular Granular Granular
Table 2--12 lots of NDR 47085
Base polymer properties
Lot Ethylene Propylene ENB Tc Polymer
Designation wt. % wt. % wt. % deg. C mwd
RC0226SDAC 70.0 25.5 4.5 21 ~2.8
RC0226SDAF 69.7 25.7 4.6 19 ~2.8
RC0326SDAC 69.9 26.0 4.2 20 ~2.8
RC0426SDAA 69.9 25.7 4.7 18 ~2.8
RC0426SDAD 69.5 25.6 4.9 18 ~2.8
RC0526SDAB 69.6 25.9 4.5 18 ~2.8
RC0626SDAB 69.4 25.8 4.8 18 ~2.8
RC0726SDAA 69.4 25.9 4.7 18 ~2.8
RC0726SDAD 69.7 25.4 4.9 18 ~2.8
RC1226SDAD 69.4 25.9 4.7 18 ~2.8
RC1326SDAB 69.6 26.2 4.2 17 ~2.8
RC1326SDAE 69.7 25.8 4.5 18 ~2.8
Base polymer properties Product properties
Lot Polymer Product C black
Designation Mooney Mooney phr
RC0226SDAC 86 108 29
RC0226SDAF 86 108 29
RC0326SDAC 86 110 31
RC0426SDAA 85 104 27
RC0426SDAD 84 106 29
RC0526SDAB 86 109 30
RC0626SDAB 87 107 28
RC0726SDAA 85 108 31
RC0726SDAD 84 105 29
RC1226SDAD 87 110 30
RC1326SDAB 87 107 28
RC1326SDAE 87 108 28
Table 3--particle size distribution particle consistency
Save information GPC
Sieve stack Sieve stack Retained C-black Results
opening (mm) (U.S. std. Mesh) wt. % wt. % Mw/Mn
3.35 6 9.7% ~2.8
2.36 8 8.5% ~2.8
1.68 12 10.4% ~2.8
1.19 16 12.4% 15.46 ~2.8
0.84 20 11.1% ~2.8
0.59 30 12.5% ~2.8
0.42 40 11.6% ~2.8
0.30 50 8.8% 28.33 ~2.8
0.21 70 5.9% ~2.8
0.15 100 3.9% ~2.8
0.11 140 2.9% ~2.8
0.08 200 1.7% 57.40 ~2.8
0.05 270 0.6% ~2.8
Save information DCS Composition by FTIR
Sieve stack Results Ethylene Propylene ENB
opening (mm) Tc wt. % wt. % wt. %
3.35 19 69.9 26.1 4.0
2.36 19 69.7 26.1 4.2
1.68 19 69.6 25.9 4.6
1.19 19 69.5 25.7 4.8
0.84 18 69.2 26.3 4.5
0.59 18 69.4 26.1 4.5
0.42 18 69.5 25.8 4.7
0.30 18 69.4 25.9 4.8
0.21 18 69.4 25.8 4.8
0.15 17 69.5 25.9 4.6
0.11 17 69.6 25.7 4.7
0.08 17 69.4 27.0 3.6
0.05 17 69.7 26.2 4.1
Table 4--12 lots of NDR 37060
Base polymer properties
Lot Ethylene Propylene ENB Tc Polymer
Designation wt. % wt% wt. % deg. C mwd
RE0326SDDC 69.4 28.8 1.8 21 ~2.5
RE1026SDAA 69.1 28.5 2.4 20 ~2.5
RE1026SDAC 69.1 28.5 2.4 21 ~2.5
RE1026SDAD 69.0 28.9 2.1 21 ~2.5
RE1026SDAE 69.4 28.4 2.2 21 ~2.5
RE1126SDAC 69.3 28.7 2.0 20 ~2.5
RE1226SDAA 69.1 28.4 2.5 20 ~2.5
RE1326SDAC 68.8 28.8 2.4 18 ~2.5
RE1326SDAD 68.5 29.1 2.4 17 ~2.5
RE1426SDAB 68.1 29.6 2.3 17 ~2.5
RE1426SDAE 68.2 29.6 2.2 18 ~2.5
RE1526SDAC 68.1 29.7 2.2 17 ~2.5
Base polymer properties Product properties
Lot Polymer Product C black
Designation Mooney Mooney phr
RE0326SDDC 63 81 29
RE1026SDAA 58 79 29
RE1026SDAC 61 78 28
RE1026SDAD 62 79 28
RE1026SDAE 63 81 29
RE1126SDAC 64 87 30
RE1226SDAA 58 75 29
RE1326SDAC 64 87 34
RE1326SDAD 65 87 33
RE1426SDAB 64 84 31
RE1426SDAE 59 77 30
RE1526SDAC 55 71 28
References (1.) E.K. Easterbrook and R.D. Allen, "Ethylene-propylene rubber," Rubber Technology 3rd Edition, M. Morton, editor, Van Nostrand Reinhold, New York New York, state, United States New York, Middle Atlantic state of the United States. It is bordered by Vermont, Massachusetts, Connecticut, and the Atlantic Ocean (E), New Jersey and Pennsylvania (S), Lakes Erie and Ontario and the Canadian province of , pp. 260-283. (2.) G. Ver Straw, "Ethylene-propylene elastomers," Encyl. Polym. Sci., p.522(1986). (3.) J.A. Riedel and R. Vander Laan, "Ethylene propylene rubbers Ethylene propylene rubber (EPR) is an insulation used for high voltage cables. It has improved thermal characteristics over more traditional cables, such as cross-linked polyethylene, enabling a smaller cross sectional area for the same load carrying capacity. ," The Vanderbilt Rubber Handbook 13th Edition, R.F. Ohm, editor, R.T. Vanderbilt Company, Norwalk, CT, pp. 123-148. (4.) J.F. Auchter, F. Stahel and Y. Ishikawa "Ethylene-propylene elastomers," 1993, SRI Report. (5.) Chem System Report "Ethylene-propylene elastomers." (6.) "Dow, Dupont to form elastomer elastomer (ĭlăs`təmər), substance having to some extent the elastic properties of natural rubber. The term is sometimes used technically to distinguish synthetic rubbers and rubberlike plastics from natural rubber. venture," Rubber World, February 1995. (7.) "Union Carbide Union Carbide Corporation (Union Carbide) is one of the oldest chemical and polymers companies in the United States, and currently has more than 3,800 employees. is planning to enter the rubber industry with new Texas plant," Wall Street Journal, October 12, 1994. (8.) K.W. Swogger, "Application of Insite technology in the rubber/elastomer market, " proceedings of Metcon '95 Worldwide Metallocene Conference, May 1995. (9.) D.R. Parikh, B.W. Smith, M.S. Edmondson, M.J. Castille, D.J. Mangold and J.M. Winter, "Composition and structure-property, relationships of single site constrained geometry EPDM elastomers," paper No. 81, ACS (Asynchronous Communications Server) See network access server. Rubber Division, May 1997. (10.) A.U. Paeglis and A. Sen, "Granular gas-phase EPDM single-pass mix," paper No. 11, ACS Rubber Division, October 1995. (11.) C.S. Grant, R.G. Vara and S.H.K. Tang tang, in zoology tang: see butterfly fish. , "Properties and performance of EPDM produced via gas-phase process using constrainged geometry catalyst technology," paper no. 19, ACS Rubber Division, October 2002. (12.) A.U. Paeglis, "A new Nordel MG EPDM product development-NDR 37060," paper No. 2, ACS Rubber Division, October 2003. (13.) R.G. Vara, C. Daniel and J. Pillow "High molecular weight EPDM via metallocene catalyst Metallocene catalyst A transition-metal atom sandwiched between ring structures having a well-defined single catalytic site and well-understood molecular structure used to produce uniform polyolefins with unique structures and physical properties. and gas-phase process, "paper No. 1, Rubber Division, ACS, October 2003. (14.) S.L. Martin, L.C. Cady, D.P. Denton and D.L. Ramage, "Development of metallocene catalyst technology for the manufacture of ethylene-propylene-diene rubber via the gas-phase process," paper no. 17, ACS Rubber Division, October 2002. (15.) M.S. Edmondson, T.A. Plumley and D.J. Mangold, "New hydrocarbon elastomers via constrained geometry catalyst technology, " paper no. 8, ACS Rubber Division, October 1995. (16.) M.S. Edmondson, T.A. Karjala, R.M. Patel and D.R. Parikh, "Ethylene-propylene-diene elastomers via constrained geometry, catalyst technology," paper No. 36, ACS Rubber Division, May 1996. (17.) T. Allen, "Particle size measurement," Vol. 1, Powder Sampling, Fifth Ed., Chapman & Hall, London 1997. |
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