Polymer ethylene-propylene diene terpolymer

The most prevalent approach to achieve long-lasting and nonstaining ozone protection of rubber compounds is to use an inherently ozone-resistant, saturated backbone polymer in blends with a diene rubber. The ozone-resistant polymer must be used in sufficient concentration (minimum 25 phr) and must also be sufficiently dispersed to form domains that effectively block the continuous propagation of an ozone-initiated crack through the diene rubber phase within the compound. Elastomers such as ethylene-propylene-diene terpolymers, halogenated butyl mbbers, or brominated isobutylene-co-para-methylstyrene elastomers have been proposed in combination with NR and/or butadiene rubber. 

Medintseva, T.I., Dreval, V.E., Erina, N.A., and Prut, E.V., Rheological properties thermoplastic elastomers based on isotactic polypropylene with an ethylene-propylene-diene terpolymer, Polym. Sci. A, 45, 2032, 2003. 

Ethylene-propylene-diene terpolymers (EPDM), with their inherent complexity in structural parameters, owe their tensile properties to specific structures dictated by polymerization conditions, among which the controlling factor is the catalyst used in preparing the polymers. However, no detailed studies on correlation between tensile properties and EPDM structures have been published (l,2). An unusual vulcanization behavior of EPDMs prepared with vanadium carboxylates (typified by Vr g, carboxylate of mixed acids of Ccj-Cq) has been recently reported Q). This EPDM attains target tensile properties in 18 and 12 minutes at vulcanization temperatures of 150 and l60°C respectively, while for EPDMs prepared with V0Cl -Et3Al2Cl or V(acac) -Et2AlCl, about 50 and 0 minutes are usually required at the respective vulcanization temperatures, all with dieyclopentadiene (DCPD) as the third monomer and with the same vulcanization recipe. This observation prompted us to inquire into the inherent structural factors... 

Polymer International 51,No.7, July 2002, p.601-6 PHYSICAL STUDIES OF FOAMED REINFORCED RUBBER COMPOSITES. PART I. MECHANICAL PROPERTIES OF FOAMED ETHYLENE-PROPYLENE-DIENE TERPOLYMER AND NITRILE-BUTADIENE RUBBER COMPOSITES... 

Sulfonation is very useful chemical modification of polymer, as it induces high polarity in the polymer changing its chemical as well as physical properties. Sulfonated polymers are also important precursors for ionomer formation [75]. There are reports of sulfonation of ethylene-propylene diene terpolymer (EPDM) [76, 77], polyarylene-ether-sulfone [78], polyaromatic ether ketone [79], polyether ether ketone (PEEK) [80], styrene-ethylene-butylene-styrene block copolymer, (SEBS) [81]. Poly [bis(3-methyl phenoxy) phosphozene] [82], Sulfonated polymers show a distinct peak at 1176 cm"1 due to stretching vibration of 0=S=0 in the -S03H group. Another peak appears at 881 cm 1 due to stretching vibration of S-OH bond. However, the position of different vibrational bands due to sulfonation depends on the nature of the cations as well as types of solvents [75, 76]. 

At room temperature, PE is a semi-crystalline plastomer (a plastic which on stretching shows elongation like an elastomer), but on heating crystallites melt and the polymer passes through an elastomeric phase. Similarly, by hindering the crystallisation of PE (that is, by incorporating new chain elements), amorphous curable rubbery materials like ethylene propylene copolymer (EPM), ethylene propylene diene terpolymer (EPDM), ethylene-vinyl acetate copolymer (EVA), chlorinated polyethylene (CM), and chlorosulphonated polyethylene (CSM) can be prepared. 

Figure 12.1 A typical 129Xe NMR spectrum of a polymer at a temperature above the glass transition temperature (T ) (here ethylene-propylene diene terpolymer (EPDM)) in a ca. 1,000,000 Pa Xe atmosphere. The signal of the free gas is used as an internal...

Manchado M. A. L., Biagiotti J. and Kenny J. M., Rheological behavior and processability of polypropylene blends with rubber ethylene propylene diene terpolymer. J. Appl. Polym. Sci. 81 (2001) pp. 1-10. 

Ethylene/propylene co-polymers and ethylene/propylene/diene terpolymers 1045... 

These polyolefin rubbers are produced in two main types the saturated co-polymers, ethylene propylene rubber (EPM), and the unsaturated ethylene-propylene diene terpolymer (EPDM). The monomers are co-polymerised in ziegler natta type catalysts. The EPDM types are capable of sulfur vulcanisation as they contain, in addition to olefins, a non coagulated diene as the third monomer. 

In a typical experiment, 2g of ethylene-propylene-diene terpolymer was dissolved in freshly distilled toluene in a 3-necked flask under an argon atmosphere. Two ml of Shirakawa catalyst (Ti(OBu) /ALEt ) (9) were added to the flask by means of a syringe. Subsequently, all solvents were slowly evaporated under vacuum by rotating the flask to ensure a uniform film of the polymer on the wall of the flask. Next, acetylene gas was introduced into the flask at room temperature. The polymerization of acetylene was evident from the color change of the film (brown black). The flask was left closed and filled with acetylene overnight at room temperature. Subsequently, the... 

The choice of date range is arbitrary. The number of journal articles for each year was obtained from a search of electronic version of English-based polymer and polymer-related journals using the keywords polyolefin and blends. Within polyolefin keyword, the subkeywords used in the search were polyethylene (PE, LLDPE, LDPE, HDPE, UHMWPE, PE, etc.), polypropylene (PP, iPP, sPP, aPP, etc.), polybutene-1, poly-4-methylpentene-l, ethylene-diene monomer, ethylene-propylene-diene terpolymer, ethylene propylene rubber, thermoplastic olefins, natural rubber (NR), polybutadiene, polyisobutylene (PIB), polyisoprene, and polyolefin elastomer. For the polyolefin blends patent search, polymer indexing codes and manual codes were used to search for the patents in Derwent World Patent Index based on the above keywords listed in the search strategy. 

The objects of our investigations were four kinds of elastomers, of different structure and polarity, viz. cis-1,4-polybutadiene (BR)> butadiene-acrylonitrile copolymer (NBR), isobutylene-isoprene copolymers (IIR) and ethylene-propylene-diene terpolymer (EPT). They were mixed with plastomers low density polyethylene (PE] ), polystyrene (PS), polytetrafluoroethylene (PTFE), polyvinyl chloride (PVC), polycaproamide (PCA) and polyacrylonitrile (PAN) (Table 1). The concentration of the plastomers in the mixtures was changed in the range from 0 to 50 pph of the elastomer. The polymers were blended at temperature T = 423 K by means of the micromill of the Plasti--Corder apparatus. After 24 hours, crosslinking substances, dicurayl peroxide (DCP) or sulphur and diphenylguanidine (S, DPG), were added at room temperature. The composition of the mixtures is given in Table 2. 

P.V. Anil Kumar, S. Anilkumar, K.T. Varughese, S. Thomas. Transport behavior of aromatic hydrocarbons through high density polyethylene/ ethylene propylene diene terpolymer blends. Journal of Polymer Research 2012 19 9794... 

Zaharescu, T., Assessment of compatibility of ethylene-propylene-diene terpolymer and polypropylene. Polymer Degradation and Stability 2001,73,113-118. 

Kuila, T, Srivastava, S. K., and Bhowmick, A. K. 2009. Ethylene vinyl acetate/ethylene propylene diene terpolymer-blend-layered double hydroxide nanocomposites. Polymer Engineering and Science 49 585-591. 

Grigoryeva, O. P. and Karger-Kocsis, J. 2000. Melt grafting of maleic anhydride onto an ethylene-propylene-diene terpolymer (EPDM). European Polymer Journal 36 1419-1420. 

The co-continuous structure and the final rheological properties of an immiscible polymer blend are generally controlled by not only the viscoelastic and interfacial properties of the constituent polymers but also by the processing parameters. For example, the effect of plasticizer on co-continuity development in blends based on polypropylene and ethylene-propylene-diene-terpolymer (PP/EPDM), at various compositions, was studied using solvent extraction. The results showed more rapid percolation of the elastomeric component in the presence of plasticizer. However, the same fuUy co-continuous composition range was maintained, as for the non-plasticized counterparts (Shahbikian et al. 2011). It was also shown that the presence of nanoclay narrows the co-continuity composition range for non-plasticized thermoplastic elastomeric materials (TPEs) based on polypropylene and ethylene-propylene-diene-terpolymer and influences their symmetry. This effect was more pronounced in intercalated nanocomposites than in partially exfoliated nanocomposites with improved clay dispersion. It seems that the smaller, well-dispersed particles interfere less with thermoplastic phase continuity (Mirzadeh et al. 2010). A blend of polyamide 6 (PA6) and a co-polyester of... 

An elastomer which upon heating turns into regularly behaving linear polymer. Polystyrene-polybutadiene block copolymers, polypropylene blends with ethylene-propylene-diene terpolymer provide examples. 

Where high damping is required polymers such as ethylene-propylene-diene terpolymer, butyl, chlorobutyl, bromobutyl and acrylonitrile butadiene copolymer can be considered. 

Saturated polymers such as butyl and ethylene-propylene-diene terpolymer are more difficult to bond and generally exhibit lower bond strengths compared to those found with the general purpose polymers. Once a degree of functionality is introduced into the polymer such as with chloro or preferably bromobutyl rubber and chlorosulfonated polyethylene (Hypalon ) then the ability to bond is enhanced. 

There are two types of disparities between the steady-state and dynamic flow behavior, one related to the interlayer slip (Eq. (2.56)) and the second to the flow engendered migration of the low viscosity component to the high stress location. Blends of liquid crystal polymer (LCP) with polycarbonate (PC) or poly(ethylene-terephthalate) (PET) may serve as an example of the first type [321,322], whereas those of EPDM (ethylene-propylene-diene terpolymer) with poly(vinylidene-co-hexafluor-opropylene), Viton , exemplify the second [323-325]. In both cases the steady-state shearing was performed in a capillary viscometer- the viscosity ratio of the dynamic to the steady-state data for these two blends was about two and six, respectively. 

Ethylene propylene diene terpolymers (EPDM) can be used to improve the ozone resistance of bromobutyl/natural rubber binary polymer blends, eliminating the need for chemical antiozonants. Addition of 10 phr of EPDM (with a high ethylidene norbornene, ENB, content of9%) to a 50/50 bromobutyl rubber/natural rubber blend results in a compound vdth good static and dynamic ozone resistance. EPDM with a 5.7% ENB level is another suggested grade of polymer. 

The mechanical properties of polymer nanocomposites are also influenced by the chemical treatment of nanoparticles due to the different neighborhood in the material. The free volume that characterizes the density of material is modified and, consequently, the penetration of fluids (solvents, oxygen) is rather favorable to degradation. The diffusion of xylene in ethylene-propylene diene terpolymer is unlike, if material presents different consistency (Fig. 14, [191]). The competitive radiochemical processes, crosslinking of polymer and degradation of covering layer are the most important reasons responsible for the different shapes of swelling curves. 

Schaefer et al. (19) studied the interphase microstructure of ternary polymer composites consisting of polypropylene, ethylene-propylene-diene-terpolymer (EPDM), and different types of inorganic fillers (e.g., kaolin clay and barium sulfate). They used extraction and dynamic mechanical methods to relate the thickness of absorbed polymer coatings on filler particles to mechanical properties. The extraction of composite samples with xylene solvent for prolonged periods of time indicated that the bound polymer around filler particles increased from 3 to 12 nm thick between kaolin to barium sulfate filler types. Solid-state Nuclear Magnetic Resonance (NMR) analyses of the bound polymer layers indicated that EPDM was the main constituent adsorbed to the filler particles. Without doubt, the existence of an interphase microstructure was shown to exist and have a rather sizable thickness. They proceeded to use this interphase model to fit a modified van der Poel equation to compute the storage modulus G (T) and loss modulus G"(T) properties. 

To meet these desirable properties, the appropriate polymer to consider would be ethylene - propylene-diene terpolymer (EPDM). In the manufacture of a cost effective, impermeable membrane system, EPDM rubber is the right choice as a discreet material for improved waterproofing and protective lining applications in roofing and other uses in the construction sectors [125]. 

The high diffusion speed of small molecules (even under nearcritical conditions) in comparison with ordinary solvents and the dissolution selectivity of such systems can be used in the extraction of low-molecular organic products out of amorphous polymeric materials. Some results for acrylonitrile containing (co-) polymers/blends and thermoplastic polymers like ethylene-propylene-diene terpolymers are reported. 

The possibilities of SFE were studied on glassy polymers and on ther-moplasts, viz. acrylonitrile containing (co-) polymers and ethylene-propylene -diene terpolymers, respectively. We first investigated, in window-autoclave systems, the solubility of the impurities in CO2 and/or ethylene. Fig. 3 shows some typical examples. Most organic impurities of the studied polymers could be dissolved at pressures and temperatures well within the reach of the standard processing equipment. 

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