DOCSLIB.ORG

How to Control Porosity in Extruded EPDM Dense Pro Le

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
How to Control Porosity in Extruded EPDM Dense Pro Le 14 Rubber & Plastics News • March 22, 2021 www.rubbernews.com www.rubbernews.com Technical Technical volatiles can vaporize. Once this filler surface moisture evapo- rates it allows more filler inter- How to control porosity in action with other ingredients such as PEG and other process aids. Desiccants like CaO are added late in the mixing cycle to extruded EPDM dense pro le prevent absorption of moisture. A two-roll mill below the mixer By Greg Li, Santosh Bawiskar The authors further can be used to complete the and Sharon Wu Executive summary mixing, optimize dispersion and let Dow Packaging & Specialty Plastics Greg Li is a research scien- volatiles escape by creating and re- Introduction The fully saturated hydrocarbon backbone of EPDM rubber results in outstanding weatherability, tist in North newing the surface. The roll speed EPDM dense profile and manu- ultraviolet stability and low/high temperature resistance. Therefore, EPDM rubber has been estab- America Pack- is adjusted so air is not trapped in facturing process lished as the primary polymer choice for automotive sealing applications (both dense and sponge aging & Spe- the compound, as this can result in The fully saturated hydrocar- weatherstrip). cialty Plastics porosity as well. Finishing ingredi- bon nature of EPDM rubbers re- A typical manufacturing process of automotive dense weatherstrip involves profile extrusion fol- Technical Ser- ents like slab dips must be appro- sults in outstanding weather- lowed by continuous vulcanization. Excessive porosity in extruded and fully cured dense profiles re- vice & Develop- priately selected as these can be ability, ultraviolet stability and mains a big challenge to many automotive weatherstrip tier suppliers. ment at Dow sources of volatiles. low/high temperature resistance. In this study, we systematically studied the mechanism of porosity formation in EPDM dense pro- Chemical Co. Therefore, EPDM rubber has file. The major factors for porosity in EPDM dense profile were summarized as compound formulation; His responsibil- Extrusion been established as the primary extrusion conditions; and vulcanization conditions. ities include the Li The extrusion step also can be polymer choice for automotive A porosity-free technical solution for EPDM dense profile also was presented. development used to control porosity. As the sealing applications. of Nordel-brand EPDM prod- compound is being conveyed ucts, formulations and applica- through the extruder, it imparts TECHNICAL NOTEBOOK • It reduces mechanical prop- ation and bubble growth has to result in porosity. tion and processing develop- additional mixing due to the mo- Edited by John Dick erties such as tensile, tear, ad- be mitigated by controlling the Calcium oxide can help bind ments. tion of the screw and the type of hesion, etc.; volatiles/air entrapment, or by the moisture by functioning as a Santosh Bawiskar is a fellow screw design. With a two-stage Automotive body sealing (both • It changes performance char- applying external pressure on desiccant. Further oils get ab- at Dow. He has more than 20 screw, with a devolatilization sec- dense and sponge weatherstrip) acteristics (e.g. sealing) as the the extrudate. sorbed on porous filler surfaces, years of experi- tion, it is possible to pull vacuum, represents one of the largest ap- stiffness and density are reduced which may or may not incorpo- ence in materi- which allows extraction of the vola- plications, accounting for about (in cases of high porosity); and Variables affecting porosity rate into the EPDM matrix and al development, tiles. The back pressure due to the 20 percent of the total worldwide • Customer specifications don’t The compound design (formu- can act as a source of volatiles. compounding die allows volatiles to escape from 1,2 consumption of EPDM. allow porosity even if perfor- lation) and the subsequent man- Low molecular weight oils also and processing the vent and proper screens/die A typical manufacturing pro- mance is unaffected. ufacturing steps can impact po- are more volatile and a source of of elastomers. design can be used to adjust this. cess of automotive dense weather- The mechanism of porosity or rosity of the cured profile parts. porosity. Many low molecular B a w i s k a r Generally, higher extrusion strip includes the following steps: bubble formation involves bubble The manufacture of an extruded weight ingredients like process graduated with temperatures and screw speeds • Compound formulating and nucleation followed by bubble dense profile broadly involves three aids and curatives at low concen- a doctorate in help devolatilization, although mixing; growth. During extrusion, nucle- steps: compound mixing; extrusion trations can have high volatility, polymer engi- Bawiskar there is an upper limit for the • Profile extrusion; and ation occurs when the rubber and shaping; and curing. which can cause porosity. neering from extrudate temperature consider- • Curing. material is supersaturated with Each of these steps can con- Purity of these ingredients also the University of Akron and an ing the possibility of scorch. A volatile materials and the vapor tribute to the formation of poros- is critical. Volatiles also can result MBA from Clarion University. good screw design will avoid Porosity in dense EPDM profile pressure of the volatiles exceeds ity in an extruded part. Con- from byproducts of the curing re- He serves on the Board of the dead spots, ensure mixing and Porosity is the unintentional the external pressure on the ex- versely, optimizing these steps action. For example, peroxide de- TPE Special Interest Group of surface renewal, allow a depres- formation of bubbles or voids in trudate. This is followed by diffu- can help prevent porosity. composition can result in volatiles the Society of Plastics Engineers. surized zone in a two-stage screw an extruded or molded dense sion of the volatile materials to like acetone being formed. Sharon Wu is a product develop- and result in adequate tempera- part. In the case of sponge or the nuclei, which results in bub- Compound design Besides the compound formula- ment leader who oversees the ture buildup. foamed parts, the bubbles or cells ble growth. An EPDM formulation consists tion, the choice of EPDM rubber Nordel EPDM product and In the case of hot feed extru- are intentionally created by us- Although porosity formation is of fillers, oils, process aids, cure also is critical. Typically, EPDM technology innovation pipeline, sion, the additional warming ing physical or chemical blowing mostly due to volatiles as trapped package and other ingredients. with low volatile organic compound and leads a global team to de- step on a two-roll mill also can agents. In the case of dense ex- air during mixing, milling or ex- Many of these ingredients are (VOC) and high Mooney viscosity is velop next-generation EPDM help reduce volatiles and mois- truded parts (for example weath- trusion also can cause this. polar and not easily wetted by preferred for compound design to with new, valu- ture, which may have been ab- erstripping, hose, profiles, etc.) Therefore, in order to control the non-polar EPDM. If not fully incorporate all the ingredients and able properties. sorbed during storage. the porosity is undesired because: porosity formation during dense wetted, the filler surface can act enable the compound to resist any Her career • It is difficult to control di- profile manufacturing process, as heterogeneous nucleation bubble formation and growth. Due with Dow be- Curing mensions of a porous part; the mechanism of bubble nucle- sites. This is especially true with to the inherent feature of Nor- gan in 2008, As the material exits the die, non-black fillers, which tend to del-brand EPDM manufacturing and she has led the external pressure drops to Table 1: List of dense compound formulations. be more polar. process, low VOC Nordel EPDM is multifunction- atmospheric levels and bubble Use of process aids like poly- a favorable polymer choice for an al global teams nucleation and growth may oc- ethylene glycol (PEG) helps filler EPDM-dense compound. toward the cur. This is especially true with wetting. Another issue with commercial- Wu lower viscosity or lower melt many non-black fillers (clay, etc.) Mixing ization of a se- strength feedstocks, which do is that they inherently have a Mixing is a critical step to en- ries of polyolefin elastomers for not resist bubble nucleation. high moisture content, which can sure good dispersion of all ingre- the transportation, infrastruc- Lowering extrudate tempera- ture and packaging markets. Table 2: One-pass mixing procedures. ture can help if bubble formation She received her doctorate from occurs instantly after exiting the the Georgia Institute of Technolo- die. Curing also helps build com- gy, and her research has covered pound viscosity and prevent po- many aspects of polyolefin mate- rosity. Thus, the kinetics of bub- rials science, including structure/ ble formation must be slower property relationship, prod- than the kinetics of curing in or- uct-process development and der to prevent porosity. polyolefin characterization. The cure rate and cure set-up Wu’s research has resulted (hot air, microwave, salt bath, in 16 peer-reviewed journal autoclave, etc.) play a significant articles, 15 granted U.S. pat- role in controlling porosity. The ents and more than 26 patent autoclave process is most forgiv- applications. ing for porosity as external steam pressure can be applied to dients and can be used to elim- prevent porosity development. inate volatiles like moisture In the hot air cure and salt bath coming from fillers and other process, curing starts from the ingredients. Good dispersion surface and progresses inward, ensures that the filler surface allowing time for porosity develop- is not a source for heteroge- ment. In microwave curing, cure neous nucleation. Good mixing rate is more uniform throughout also ensures that the oil is well the cross-section, and using a incorporated into the EPDM shock oven can help form a skin phase rather than remaining layer quickly.
Load more

Recommended publications
  • Comparing Strength Properties of Natural and Synthetic Rubber Mixtures
    Sustainable Construction and Design 2011 COMPARING STRENGTH PROPERTIES OF NATURAL AND SYNTHETIC RUBBER MIXTURES T. Renner, L. Pék Institute for Mechanical Engineering Technology, Faculty of Mechanical Engineering, !"#$%&'$(#%*#+(",'+$-.%/122P.%45#67,- www.geti.gek.szie.hu Abstract: During in our research work we examine the condition of developing elastomer – metal connection at manufacturing machine – and car industry hybrid parts. As a first step we have carried out comparison tests relating to the strength properties of synthetic – and natural rubber mixtures. During tests we have compared four mixtures used often in the practice (NR, NBR, EPDM, CR) in three characteric hardnesses (43 Sh 0, 57Sh 0, 72Sh 0). In addition to hardness we have measured the elongation at rupture and the density, too. As a continuation of our tests we researched what connection is between the surface roughness of metal plate and the elastomer – metal bonding formed. Keywords: rubber mixtures, latex, hybrid parts, strength properties 1 INTRODUCTION: CHARACTERIZING THE MIXTURES EXAMINED The natural rubber is the most often used type of mixture of the rubber industry nowadays which is produced from the milk-like fluid (from latex) of certain tropical trees. The latex is a colloid state dispersion, the rubber is precipipated (killed) by acetic – or formic acid from it then is washed, pressed, dried or smoked [2]. After these the quality classification takes place then it is packed in to bales and according to the so called „green book” it is put into commercial circulation. This handbook was accepted by the International Federation of Rubber Producting Nations in 1960 which is a standard publication in classifying rubbers up to present days.
    [Show full text]
  • A New Approach for Reclaiming of Waste Automotive EPDM Rubber Using Waste Oil
    Polymer Degradation and Stability 129 (2016) 56e62 Contents lists available at ScienceDirect Polymer Degradation and Stability journal homepage: www.elsevier.com/locate/polydegstab A new approach for reclaiming of waste automotive EPDM rubber using waste oil * Malihe Sabzekar a, Gholamhossein Zohuri b, c, , Mahdi Pourafshari Chenar a, Seyed Mohammadmahdi Mortazavi d, Majid Kariminejad e, Said Asadi e a Chemical Engineering Department, Faculty of Engineering, Ferdowsi University of Mashhad, P.O. Box 91775-1111, Mashhad, Iran b Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, P.O. Box 91775-1111, Mashhad, Iran c Environmental Chemistry Research Center, Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran d Polymerization Engineering Department, Iran Polymer and Petrochemical Institute (IPPI), P.O. Box 14965/115, Tehran, Iran e Baspar Sazeh Toos Co. of Part Lastic Group, P.O. Box 91895-196, Mashhad, Iran article info abstract Article history: The disposal of polymeric and especially rubber materials is an important global issue. In this work we Received 28 July 2015 have used disulfide oil (DSO), the oily waste produced in gas refineries, as a chemical agent for mech- Received in revised form anochemical reclaiming of waste EPDM rubber at a specific operation condition. The devulcanization 6 January 2016 reaction was performed using different concentrations of DSO (5 and 7 phr) and different temperatures Accepted 4 April 2016 (220, 250 and 290 C). The results confirmed the effectiveness of DSO in decreasing the crosslink density Available online 5 April 2016 up to 73% at specific reaction conditions. Subsequently, two different portions of the devulcanized rubber (RR) (20 and 40 wt %) were blended with the virgin EPDM rubber to assess the reusability of the recycled Keywords: Waste EPDM product.
    [Show full text]
  • The Curing and Degradation Kinetics of Sulfur Cured EPDM Rubber A
    The Curing and Degradation Kinetics of Sulfur Cured EPDM Rubber A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science By ROBERT J. WEHRLE B.S., Northern Kentucky University, 2012 Wright State University 2014 WRIGHT STATE UNIVERSITY GRADUATE SCHOOL August 29, 2014 I HEREBY RECOMMEND THAT THE THESIS PREPARED UNDER MY SUPERVISION BY Robert Joseph Wehrle ENTITLED The Curing and Degradation Kinetics of Sulfur Cured EPDM Rubber BE ACCEPTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE. Eric Fossum Ph.D. Thesis Director David A. Grossie, Ph.D. Chair, Department of Chemistry Committee on Final Examination Eric Fossum, Ph.D. William A. Feld, Ph.D. Steven B. Glancy, Ph.D. Kenneth Turnbull, Ph.D. Robert E. W. Fyffe, Ph.D. Vice President for Research and Dean of the Graduate School Abstract Wehrle, Robert J. M.S, Department of Chemistry, Wright State University, 2014. The Curing and Degradation Kinetics of Sulfur Cured EPDM Rubber. Ethylene‐propylene‐diene (EPDM) rubbers containing varying amounts of diene were cured with sulfur using either a moving die rheometer (MDR) or a rubber process analyzer (RPA). The effect of removing curatives and how the curing reaction changed was explored. Kinetic data was extracted from the rheology plots and reaction rate constants were determined by two separate ways: manually choosing points of interest or by a computer model. iii TABLE OF CONTENTS Page 1. Introduction 1 1.1 EPDM Overview 1 1.2 Preparation of EPDM 2 1.2.1 Ziegler‐Natta Catalysts 2 1.2.2 Metallocene Catalysts 4 1.3 Cross‐link Chemistry 5 1.3.1 Peroxide Cure 5 1.3.2 Sulfur Cure 6 1.3.3 Cross‐link Sites 8 1.3.3.1 Polymer Branching 9 1.3.4 Rubber Ingredients 10 1.3.4.1 Non‐curative Ingredients 10 1.3.4.2 Curative Ingredients 11 1.4 Kinetics 12 1.5 Instrumentation 13 2.
    [Show full text]
  • Lled Ethylene-Propylene-Diene Monomer/Styrene-Butadiene Rubber (EPDM/SBR) Composites: Mechanical, Swelling, and Morphological Properties
    Halloysite Nanotubes (HNTs)-lled Ethylene-propylene-diene Monomer/styrene-butadiene Rubber (EPDM/SBR) Composites: Mechanical, Swelling, and Morphological Properties Sendil Ganeche P ( [email protected] ) AVC College of Engineering Balasubramanian P AVC College of Engineering Vishvanathperumal S SA Engineering College Research Article Keywords: EPDM/SBR, HNTs, Mechanical properties, Swelling resistance Posted Date: July 6th, 2021 DOI: https://doi.org/10.21203/rs.3.rs-652747/v1 License: This work is licensed under a Creative Commons Attribution 4.0 International License. Read Full License Loading [MathJax]/jax/output/CommonHTML/jax.js Page 1/14 Abstract Halloysite nanotubes (HNTs) were incorporated into an EPDM/SBR rubber/styrene-butadiene rubber (SBR) composite by melt blending of HNTs into the EPDM/SBR blend. The mechanical properties, abrasion and swelling resistance of HNTs ranging from 2 parts per hundred rubber (phr) to 10 parts per hundred rubber (phr) were investigated in EPDM/SBR base rubber. Tensile strength, 100% modulus (modulus at 100 percent elongation), elongation at break and tear strength were evaluated at ambient temperature using electric universal tensile testing equipment in accordance with ASTM D-412. Hardness, abrasion and swelling resistance were determined using Shore-A Durometer, DIN abrader and immersion techniques, respectively. The results show that increasing HNT content increased tensile strength, tear strength, hardness (stiffness), and crosslink density. The surface morphology of tensile- fractured material was studied using eld-emission scanning electron microscopy (FE-SEM). According to FE-SEM results, the most roughness of the surface was seen at HNTs lled rubber nano-composites. 1. Introduction Without some kind of reinforcement, a rubber substance, whether polar or non-polar, has weak physico-mechanical properties [1].
    [Show full text]
  • A Review of the Potential Health and Safety Risks from Synthetic Turf Fields Containing Crumb Rubber Infill
    A REVIEW OF THE POTENTIAL HEALTH AND SAFETY RISKS FROM SYNTHETIC TURF FIELDS CONTAINING CRUMB RUBBER INFILL Prepared for New York City Department of Health and Mental Hygiene New York, NY Prepared by TRC Windsor, Connecticut May 2008 A REVIEW OF THE POTENTIAL HEALTH AND SAFETY RISKS FROM SYNTHETIC TURF FIELDS CONTAINING CRUMB RUBBER INFILL Prepared for New York City Department of Health and Mental Hygiene New York, NY Prepared by TRC Windsor, Connecticut Report Authors: Elizabeth Denly Katarina Rutkowski Karen M. Vetrano, Ph.D. NYC DOHMH Reviewers: Andriana Azarias, Nancy Clark, Nathan Graber, Paromita Hore, Maureen Little TRC Project No. 153896 May 2008 TRC 21 Griffin Road North Windsor, Connecticut 06095 Telephone 860-298-9692 Facsimile 860-298-6399 TABLE OF CONTENTS SECTION PAGE LIST OF ACRONYMS .................................................................................................................... iv EXECUTIVE SUMMARY .........................................................................................................ES–1 1.0 INTRODUCTION .............................................................................................................. 1-1 1.1 Background and Purpose of Review............................................................................... 1-1 1.2 Scope of Work................................................................................................................ 1-3 1.2.1 Literature Search....................................................................................................
    [Show full text]
  • PUBLIC SUBMISSION Posted: April 22, 2016 Tracking No
    Page 1 of 3 As of: 4/28/16 11:22 AM Received: April 15, 2016 Status: Posted PUBLIC SUBMISSION Posted: April 22, 2016 Tracking No. 1k0-8p39-1hhr Comments Due: May 02, 2016 Submission Type: Web Docket: ATSDR-2016-0002 Collections Related to Synthetic Turf Fields with Crumb Rubber Infill 0923-16PJ Comment On: ATSDR-2016-0002-0003 Collections Related to Synthetic Turf Fields with Crumb Rubber Infill ATSDR-2016-0002 Document: ATSDR-2016-0002-0024 Comment on FR Doc # 2016-03305 Submitter Information Name: Jerome Silbert M.D. Address: 06437 Email: [email protected] General Comment I am a physician trained in pathology with boards in anatomic pathology, clinical pathology and blood banking. I have been following the controversy over tire crumb rubber for several years and have reviewed a number of the published studies on this matter. I congratulate the governmental agencies for taking up this important matter to establish whether ground up tires used on artificial grass fields in the form of crumb rubber is a suitable for children to play on. After reviewing a number of studies I must conclude that, thus far, the studies are totally inadequate to establish the safety of tire crumb rubber for artificial grass playing fields. Background: A recent study at Yale University was done on shredded tires and tire crumb rubber by Gaboury Benoit, Professor of Environmental Chemistry, Professor of Environmental Engineering, Co- Director of the Hixon Center for Urban Ecology, Director of the Center for Coastal and Watershed Systems. Crumb rubber from tires is a very heterogeneous material coming from tires that have many different chemical compositions so it is legitimate to include shredded tires that are used on https://www.fdms.gov/fdms/getcontent?objectId=0900006481f6e980&format=xml&show..
    [Show full text]
  • EPDM-Rubber-And-Itâ
    INDIAN RUBBER MANUFACTURERS RESEARCH ASSCOCIATION Affiliated to Ministry of Commerce & Industry GOVT. OF INDIA EPDM RUBBER AND IT’S BENEFITS EPDM RUBBER AND IT’S BENEFITS Suchismita Sahoo Assistant Director IRMRA ABOUT IRMRA ▪Established in 1958, as a small scale R& D Institute, is now an internationally well known Centre of Excellence both for non-tyre & tyre sectors . ▪At present, IRMRA is under jurisdiction of Dept. of Industrial Policy & Promotion, Ministry of Commerce & Industry, Govt. of India, New Delhi. ▪In the last 60 years, with the help of state-of-the-art facilities created with the financial assistance granted by Ministry of Commerce & Industry, Govt. of India and expertise developed by the scientists of IRMRA, it has rendered remarkable service to rubber Industries . 2 OUR SERVICES ▪Testing of rubber and allied materials ▪Training and Manpower Development ▪Third Party Inspection Services ▪Research and Development 3 WHAT IS RUBBER ? The single most important property of rubbers is their ability to undergo large elastic deformations, that is, to stretch and return to their original shape in a reversible way. • Rubber is long chain polymer with molecular weight in the range of 10 6 – 10 7 • Rubber chains remain in a coiled state • Rubber molecules can stretch upto 1000% elongation by uncoiling of the chains • Rubber as a material is highly amorphous in nature. • Rubber molecules always remain under Brownian motion at room temperature. • Rubber is inherently soft and weak in nature • Primarily comprises of carbon and hydrogen with few exceptions. 4 TYPES OF RUBBER Rubber can be broadly classified into natural and synthetic rubber Natural Rubber : Derived from the plant Hevea Brasiliensis and is the first and most commonly used rubber.
    [Show full text]
  • Characterization and Surface Modification of Rubber From
    Characterization and Surface Modification of Rubber from Recycled Tires Thèse Huan Liang Doctorat en Chimie Philosophiae doctor (Ph. D.) Québec, Canada © Huan Liang, 2015 Characterization and Surface Modification of Rubber from Recycled Tires Thèse Huan Liang Sous la direction de : Josée Brisson, directrice de recherche Résumé Les pneus en fin de cycle de vie soulèvent de graves problèmes environnementaux. Ils doivent être éliminés ou recyclés. En raison de leur structure réticulée, les pneus ne fondent pas ni ne se dissolvent. Ils sont généralement broyés en poudre (caoutchouc de pneu broyé, abrévié GTR). Ensuite, ces poudres sont mélangées avec une matrice (asphalte ou polymère thermoplastique) pour réutilisation. L'industrie du recyclage se heurte à deux problèmes principaux. En premier lieu, le contrôle de technique qualité est difficile à cause du manque de solubilité de la poudre et de moyens limités pour ces petites industries. Il est nécessaire de trouver des méthodes rapides et à faible coût pour améliorer la caractérisation des GTR. Dans le présent travail, nous avons mis l'accent sur l'utilisation de ces deux techniques et sur la spectrométrie de fluorescence-X (XRF), comme il y a des rapports dans la littérature démontrant que ceux-ci peuvent être utilisés, respectivement, pour déterminer la densité de réticulation, la composition en monomères et la composition élémentaire. Un deuxième problème est la faible adhérence entre la plupart des polymères et les GTR. Ceci résulte en un manque de résistance mécanique et une tendance à l'effritement des pièces fabriquées. Certaines études se concentrent sur l'ajout de monomère et d'initiateur au GTR, afin de faire une polymérisation in-situ de chaînes greffées sur la surface.
    [Show full text]
  • Relationship Among Vulcanization, Mechanical Properties and Morphology of Blends Containing Recycled EPDM
    recycling Article Relationship among Vulcanization, Mechanical Properties and Morphology of Blends Containing Recycled EPDM Aline Zanchet 1,*, Aline L. Bandeira Dotta 2 and Fabiula D. Bastos de Sousa 3 1 Center of Applied Engineering, Modeling and Social Sciences—CECS, Universidade Federal do ABC—UFABC, Rua Santa Adélia, 166, Santo André-SP 09210-170, Brazil 2 Center of Exact Science and Technology, Department of Physics and Chemistry, Universidade de Caxias do Sul, Rua Francisco Getúlio Vargas, 1130, Caxias do Sul-RS 95070-560, Brazil; [email protected] 3 Technology Development Center—CDTec, Universidade Federal de Pelotas—UFPel, Rua Gomes Carneiro, 1, Pelotas-RS 96010-610, Brazil; [email protected] * Correspondence: [email protected] Received: 7 August 2017; Accepted: 14 September 2017; Published: 19 September 2017 Abstract: The production of consumption goods made of elastomer generates large amounts of vulcanized residues. The final proper environmental disposal of this material is a serious problem, which involves high costs and a possible waste of a material with high added value. The recycling of elastomers is a very important alternative since it is related directly to the protection of the environment, energy conservation, and sustainability. An option for companies that produce elastomeric residues is their incorporation in the formulations by producing polymeric blends. Thus, this work aims to prepare polymeric blends composed of ethylene-propylene diene monomer rubber (EPDM) and raw EPDM/EPDM residue (EPDM-r) in different concentrations, when the residue is ground at room temperature. The morphology of the residue, vulcanization characteristics, mechanical properties, and morphology of the blends were analyzed, showing promising results that point to the feasibility of using EPDM-r in the production of polymeric blends and as a possible solution to the problem of the final disposal of solid residues.
    [Show full text]
  • Mechanical Properties of Rubber
    8434_Harris_33_b.qxd 09/20/2001 12:30 PM Page 33.1 CHAPTER 33 MECHANICAL PROPERTIES OF RUBBER Ronald J. Schaefer INTRODUCTION Rubber is a unique material that is both elastic and viscous. Rubber parts can there- fore function as shock and vibration isolators and/or as dampers.Although the term rubber is used rather loosely, it usually refers to the compounded and vulcanized material. In the raw state it is referred to as an elastomer. Vulcanization forms chem- ical bonds between adjacent elastomer chains and subsequently imparts dimen- sional stability, strength, and resilience. An unvulcanized rubber lacks structural integrity and will “flow” over a period of time. Rubber has a low modulus of elasticity and is capable of sustaining a deformation of as much as 1000 percent. After such deformation, it quickly and forcibly retracts to its original dimensions. It is resilient and yet exhibits internal damping. Rubber can be processed into a variety of shapes and can be adhered to metal inserts or mounting plates. It can be compounded to have widely varying properties.The load- deflection curve can be altered by changing its shape. Rubber will not corrode and normally requires no lubrication. This chapter provides a summary of rubber compounding and describes the static and dynamic properties of rubber which are of importance in shock and vibration isolation applications. It also discusses how these properties are influenced by envi- ronmental conditions. RUBBER COMPOUNDING Typical rubber compound formulations consist of 10 or more ingredients that are added to improve physical properties, affect vulcanization, prevent long-term dete- rioration, and improve processability.These ingredients are given in amounts based on a total of 100 parts of the rubber (parts per hundred of rubber).
    [Show full text]
  • EPDM-Granules in Sportfields
    ➢ Content 1. History of EPDM 2. What is EPDM chemically ? 3. EPDM Rubber Production 4. EPDM Properties and Applications 5. Compounding, Mixing and Vulcanisation 6. Standards for Sportsurface Granules 7. Properties of EPDM Granules and Comparison of today used Granules 8. Failures of EPDM Granules in the Past, possible Causes 9. Future for Granules in Sports Fields ISSS Technical Conference, 2018-10-25/26, Cagliari Günter Preisser 2 1. History of EPDM Rubber ISSS Technical Conference 2018-10-25/26, Cagliari Günter Preisser 3 Engine power (kW/liter engine capacity) 1968 1963 C.F.Benz1886 Source Bayer AG Development of Rubbers against thermal resistance and engine power ISSS Technical Conference 2018-10-25/26, Cagliari Günter Preisser 4 History of EPDM-Rubber 1953 K.Ziegler invents titane catalysts for ethene polymerisation to linear polyethylene G. Natta transfers this process later to propene resp. Polypropylene 1963 Ziegler and Natta receive for their work the Chemistry Nobelprice 1964 75 % of all rubbers become synthetically produced 1964 Catalyst system of Ziegler-Natta(Z-N) enables the industrial production of EPM and EPDM primarily in USA 1967 Production of first bales of EPDM from DSM in Geleen, NL, called Keltan. Plant capacity of 12´000 t/a, 2017 180´000 t/a ISSS Technical Conference 2018-10-25/26, Cagliari Günter Preisser 5 History of EPDM Rubber 1968 First EPDM-applications in Europe single ply EPDM roofings in NL still in service today, just and within the specification 50 years ago start of application of elastic granules (recycled
    [Show full text]
  • A New EPDM Grade with Improved Processing Characteristics for Automotive Hoses Applications
    A New EPDM Grade with Improved Processing Characteristics for Automotive Hoses Applications Sunny Jacob 1, Eric Jourdain 2, Milind Joshi 3, Mark F. Welker 1, Guy Wouters 2 1ExxonMobil Chemical Company 2ExxonMobil Chemical Europe Inc. 3ExxonMobil Company India Pvt. Ltd. ExxonMobil Chemical Company External Publication Number 2011.1645 Presented at the Hose Manufacturers’ Conference 2011 Technical Meeting of the Rubber & Plastic News Conference August 23-24, 2011 Cleveland, Ohio * Speaker 1 ABSTRACT Ethylene-propylene copolymers (EPDM) continue to be one of the most widely used and fastest growing synthetic rubbers. EPDM elastomer compounds are widely used in many automotive and industrial hose products, taking advantage of their outstanding thermal and oxidative stability, and their excellent chemical resistance to polar organic and aqueous inorganic fluids. Higher under hood temperatures (as a result of lower hood lines), reduced air flow within the engine area, and turbo chargers have brought about the need for greater heat-resistant compounds for items such as coolant, emission, brake hoses and air ducts. Although EPDM elastomers have been commercially available for 50 years, advancements in the area of catalyst and process technology have made it possible to design polymers with tailored properties to meet the increasingly demanding market requirements. In this paper we will review the performance of a recently commercialized EPDM elastomer grade particularly suitable for hose applications. Our studies indicate that this new grade offers an improved balance of processing, mechanical, and elastic properties for automotive hose applications. 2 INTRODUCTION Ethylene-propylene-diene elastomers (EPDM elastomers) have been established as the primary polymer choice for many automotive and industrial applications due to their outstanding weathering and heat resistance properties.
    [Show full text]