We hope this short guide on EPDM rubber, covering its makeup, properties, and applications, has been helpful to you in your sourcing. EPDM rubber is only one of several kinds of rubber used in industry today, however. For more information on the various types of rubber, you can check out our types of rubber buying guide. Guides Share:. Neoprene - What's the Difference? Select From Over , Industrial Suppliers. As expected, with increasing UFNBRP loading, the elastic contribution increases as evidenced by the decreases in sensitivity of storage modulus to test frequency and in creep compliance.
The rheological results are in line with the improvements in rebound resil- ience and compression set. The presence of chemical crosslinks in UFNBRP in conjunction with the formation of a transient network of rubber particles is thought to be responsible for such increase in elastic response. All rights reserved.
Introduction rubber phase is not vulcanized. To gain TPVs with good properties, high shear stress E-mail address: sccsr mahidol. Saleesung et al. Basically, UFRP is prepared by irradiating rubber latex and subsequently 2. Rheological properties spray drying.
Particle size of the UFRP has been were investigated using a parallel plate rheometer Physica claimed to be in a range of 50— nm by controlling MCR , Germany with a mm diameter grooved rotor. Strain and frequency sweep tests toughening thermoplastics [2,4,6—9]. Various thermo- were conducted by varying strain from 0. Dynamic mechanical behavior Santoprene and Geolast. These are different in their elas- A dynamic mechanical thermal analyzer Gabo model tomeric phase, i.
However, this technique requires costly processing equipments. Hence, the present work aims to prepare TPVs 2. Rheological and crystallization behavior as A second run with the same heating rate was performed and well as mechanical properties and phase morphology of the result recorded. Mechanical properties Tensile tests were conducted using a universal tensile 2.
The compression set test was carried out blade rotors and having a mixing chamber volume of using a compression device as per ISO Rebound 79 cm3. Thereafter, the blend was sheeted on a cooled 2-roll mill. For the test specimens to be 2. In effect, the onset of the non-linear nitrogen, and etched by hot xylene to remove the LDPE viscoelastic region is controlled by the disruption of phase to enhance phase contrast of the SEM image.
Results and discussion pronounced in the low frequency region. This implies an increase in elastic contribution of the chemical crosslinks in 3. This implies the enhancement in elastic contri- magnitude of J could be observed with increasing UFNBRP bution of the blends caused by the characteristics of the loading, which is attributed to the molecular mobility vulcanized rubber particles. This phenomenon is some- restriction via chemical crosslinks in rubber particles, as times known as the dilution effect [21—24].
In addition, it is discussed previously. Nevertheless, at high strain beyond particles having chemical crosslinks.
It is evident from the the critical shear strain, such transient network is disrupted rheological results that the blends with high UFNBRP loading could exhibit viscoelastic response close to a vulcanized rubber. Dynamic mechanical properties Fig. As illustrated in Fig.
Melting and crystallization behavior Fig. Such suppression in crystallization might be caused by the UFNBRP particles locating in the interlamellar spaces and, thus, the reduction in enthalpy of fusion and degree of crystallinity [25]. Such decreases can Fig. Evidently, the incorporation of be attributed to the dilution effect, i. In other words, the elastic contribution of the degree of crystallinity, as presented previously in Table 2, TPVs prepared in this work could successfully be enhanced and deterioration of tensile properties.
As expected, the hardness decreases with 3. The deformation taking place in the Results of oil swelling tests performed at room temper- hardness test is relatively small and largely near the test ature for 7 days are presented in Table 4.
Swelling magnitude piece surface so correlation with M5 would be expected. It is known that increase, which is more obvious when viewing their relative LDPE matrix is a thermoplastic material having excellent values.
Additionally, the decrease in degree of increase in relative properties. Such increase in properties crystallinity of the blends see also Table 2 with increasing after thermal ageing is believed to be the result of two UFNBRP loading might be responsible to some extent for effects. To support the proposed explanation of the post curing effect taking place after 3. Swelling results as Fig.
As seen in Fig. This could be blends. Conclusions [10] H. Tian, M. Tian, H. Zou, Z. Dang, L. The preparation of thermoplastic vulcanizates TPVs by [11] J. Van Dyke, M. Gnatowski, A. Nakason, M. Jarnthong, A. Kaesaman, S.
Kiatkamjornwong, carried out. Passador, A. This suggests J. HNBR has excellent resistance to sour oil and gas, steam, hot water and ozone. Physical properties e. Limitations include poor electrical properties, poor flame resistance and attack by aromatic oils and polar organic solvents.
Typical applications include accumulator bladders, diaphragms, gaskets and seals, especially for the oil and gas industries. Natural rubber is the only non-synthetic rubber and has been in commercial use since the beginning of the 20th century.
It is extracted from the sap of the Hevea Brasiliensis tree grown in renewable plantations. It is fully biodegradable. Tensile strength, elongation and abrasion resistance is excellent over a wide hardness range, and with the exception of certain formulations of polybutadiene, it has the highest resilience of all rubbers.
With its good tear strength, fatigue resistance and excellent compression set it is the ideal choice for dynamic applications at low and ambient temperatures. Weathering resistance is good for black compounds but only fair for white and coloured mixes. Although natural rubber can be used with water and some dilute acids, alkalis and chemicals, EPDM is normally preferable for most aqueous applications. Natural rubber compounds are not suitable for exposure to petroleum based oils and fuels.
It has poor resistance to elevated temperatures and is susceptible to attack by ozone unless specifically compounded with anti-ozonants. Typical applications include anti-vibration mounts, drive couplings, haul-off pads and tyres. Acrylonitrile Butadiene Rubber, usually shortened to Nitrile, was developed in as the first oil resistant rubber. Grades with high acrylonitrile content have better oil resistance whereas low acrylonitrile content gives better low temperature flexibility and resilience.
Nitrile has moderate physical properties but good abrasion resistance. Gas permeability is low. Ozone resistance and electrical properties are poor. Flame resistance is poor and it is not suitable for use with use with polar solvents e. Certain grades can be compounded with PVC to improve ageing, flame, petrol and ozone resistance. Carboxylated grades of Nitrile XNBR have improved physical properties and higher temperature resistance. Typical applications include accumulator bladders, diaphragms, gaskets, hose, liners, O-rings and seals.
They are extremely expensive and have poor physical properties and limited use at low temperatures. Typical applications include accumulator bladders, core sleeves, gaskets, O-rings and seals working in extremely harsh environments, particularly within the oil and gas industries.
Advanced properties help maintain seal integrity, reduce maintenance and operating costs and improve safety. It is used in highly aggressive chemical processing, semiconductor wafer processing, pharmaceutical, oil and gas recovery, and aerospace applications. The key properties of Polyacrylic ACM are its resistance to hot hydraulic oil and oxidation. It is also resistant to ozone and weathering and in these respects it is much superior to Nitrile Rubber.
Water resistance is poor, as is its resistance to acids and alkalis. Typical applications include automotive transmissions components requiring resistance to hot oil or fuel.
However, it has only moderate resistance to petroleum based oils and fuels. It can be considered as a good general purpose rubber with an excellent balance of physical and chemical properties. It has better chemical, oil, ozone and heat resistance than natural rubber but a rather lower level of physical properties.
Chloroprene tends to slowly absorb water and its electrical properties are poor.
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