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A R Azura - One of the best experts on this subject based on the ideXlab platform.

  • Thermal stability and aging characteristics of (natural rubber)/(waste ethylene-propylene-diene monomer terpolymer) blends
    Journal of Vinyl and Additive Technology, 2014
    Co-Authors: H. Nabil, H. Ismail, A R Azura
    Abstract:

    Comparative studies of the thermogravimetric analysis and thermo-oxidative aging of (natural rubber)/(waste ethylene-propylene-diene monomer terpolymer) (NR/W-EPDM) and (natural rubber)/(ethylene-propylene-diene monomer terpolymer) (NR/EPDM) blends were carried out. The blends were prepared at five different blend ratios (90/10, 80/20, 70/30, 60/40, and 50/50) on a two-roll mill. As the pure EPDM or W-EPDM content in the blends increased, their thermal stability also increased. The thermo-oxidative aging of these blends was done at 100°C for 48 h. Afterwards, the NR/EPDM blends exhibited better retention of properties than the NR/W-EPDM blends. Crosslink density measurements of the blends after thermal aging indicated that higher crosslink density was obtained from a higher content of EPDM or W-EPDM, a result which might be due to the high rate of radical termination leading to crosslinks in the bulk of the polymer. J. VINYL ADDIT. TECHNOL., 20:99–107, 2014. © 2014 Society of Plastics Engineers

  • Blending of Natural Rubber/Recycled Ethylene-Propylene-Diene Monomer: Cure Behaviors and Mechanical Properties
    Polymer-Plastics Technology and Engineering, 2013
    Co-Authors: Nabil Hayeemasae, Hanafi Ismail, A R Azura
    Abstract:

    In this article, blending of natural rubber with recycled ethylene-propylene-diene monomer (R-EPDM) was studied. The comparative studies of cure behaviors, mechanical properties and morphology of natural rubber/recycled ethylene-propylene-diene monomer (NR/R-EPDM) and natural rubber/ethylene-propylene-diene monomer blends (NR/EPDM) were carried out. Results indicated that the maximum torque (MH), minimum torque (ML), scorch time (ts2) and cure time (tc90) of NR/EPDM increased with increasing virgin EPDM in the weight ratio of the blend. Similar observation was also obtained for NR/R-EPDM blend except for the ML and ts2 which exhibited the opposite trend. SEM micrographs proved that the incorporation of R-EPDM up to 30 phr in the blends exhibited high roughness surface and matrix tearing line. Meanwhile, the micrographs of NR/EPDM blends showed a reduction in crack path with increasing virgin EPDM content, which led to less resistance for crack propagation and therefore, resulted in low tensile strength.

  • compounding mechanical and morphological properties of carbon black filled natural rubber recycled ethylene propylene diene monomer nr r epdm blends
    Polymer Testing, 2013
    Co-Authors: Hadeer Nabil, Hanafi Ismail, A R Azura
    Abstract:

    Abstract Blends of natural rubber/virgin Ethylene-Propylene-Diene-Monomer (NR/EPDM) and natural rubber/recycled Ethylene-Propylene-Diene-Monomer (NR/R-EPDM) were prepared. A fixed amount of carbon black (30 phr) was also incorporated. The effect of the blend ratio (90/10, 80/20, 70/30, 60/40 and 50/50 (phr/phr)) on the compounding, mechanical and morphological properties of carbon-black-filled NR/EPDM and NR/R-EPDM blends was studied. The results indicated that both the carbon-black-filled NR/EPDM and NR/R-EPDM blends exhibited a decrease in tensile strength and elongation at break for increasing weight ratio of EPDM or R-EPDM. The maximum torque (S′MH), minimum torque (S′ML), torque difference (S′MH−ML), scorch time (ts2) and cure time (tc90) of carbon-black-filled NR/EPDM or NR/R-EPDM blends increased with increasing weight ratio of virgin EPDM or R-EPDM in the blend. SEM micrographs proved that, for low weight ratios of virgin EPDM or R-EPDM, the blends exhibited high surface roughness and matrix tearing lines. The blends also showed a reduction in crack path with increasing virgin EPDM or R-EPDM content over 30 phr. This reduction in crack path could lead to less resistance to crack propagation and, therefore, low tensile strength.

  • Effects of virgin Ethylene–Propylene–Diene–Monomer and its preheating time on the properties of natural rubber/recycled Ethylene–Propylene–Diene–Monomer blends
    Materials & Design, 2013
    Co-Authors: H. Nabil, Hanafi Ismail, A R Azura
    Abstract:

    Abstract Blending of natural rubber/recycled Ethylene–Propylene–Diene–Monomer (NR/R-EPDM) blends was carried out. A fixed amount of carbon black and virgin Ethylene–Propylene–Diene–Monomer (EPDM) were also introduced into the blends. Applications of two different processing methods were carried out to improve the cure compatibility, crosslink distribution, and hence mechanical properties of the blends. Simple processing method was done by mixing the entire additives and rubbers on a laboratory-sized two-roll-mill at ambient temperature. Whereas, reactive processing method was conducted by mixing virgin EPDM, recycled EPDM and other compounding ingredients using an internal mixer, the compound was later preheated according to designated time before blending with natural rubber and carbon black. Results revealed that the enhancement of the physical and mechanical properties was significantly achieved towards preheating time of EPDM/R-EPDM blends. The improved properties in the blends suggested that the reactive processing method had led to more homogeneous blends due to a better crosslink distribution and more homogeneous carbon black distribution.

  • Compounding, mechanical and morphological properties of carbon-black-filled natural rubber/recycled Ethylene-Propylene-Diene-Monomer (NR/R-EPDM) blends
    Polymer Testing, 2013
    Co-Authors: H. Nabil, Hanafi Ismail, A R Azura
    Abstract:

    Abstract Blends of natural rubber/virgin Ethylene-Propylene-Diene-Monomer (NR/EPDM) and natural rubber/recycled Ethylene-Propylene-Diene-Monomer (NR/R-EPDM) were prepared. A fixed amount of carbon black (30 phr) was also incorporated. The effect of the blend ratio (90/10, 80/20, 70/30, 60/40 and 50/50 (phr/phr)) on the compounding, mechanical and morphological properties of carbon-black-filled NR/EPDM and NR/R-EPDM blends was studied. The results indicated that both the carbon-black-filled NR/EPDM and NR/R-EPDM blends exhibited a decrease in tensile strength and elongation at break for increasing weight ratio of EPDM or R-EPDM. The maximum torque (S′M H ), minimum torque (S′M L ), torque difference (S′M H −M L ), scorch time (ts 2 ) and cure time (tc 90 ) of carbon-black-filled NR/EPDM or NR/R-EPDM blends increased with increasing weight ratio of virgin EPDM or R-EPDM in the blend. SEM micrographs proved that, for low weight ratios of virgin EPDM or R-EPDM, the blends exhibited high surface roughness and matrix tearing lines. The blends also showed a reduction in crack path with increasing virgin EPDM or R-EPDM content over 30 phr. This reduction in crack path could lead to less resistance to crack propagation and, therefore, low tensile strength.

Hanafi Ismail - One of the best experts on this subject based on the ideXlab platform.

  • Thermal aging of bentonite-filled ethylene propylene diene monomer composites
    Journal of Applied Polymer Science, 2013
    Co-Authors: Mathialagan Muniyadi, Hanafi Ismail
    Abstract:

    Bentonite-filled ethylene propylene diene monomer (EPDM/Bt) composites were prepared using two roll mill compounding method and the effect of Bt loading on the thermal aging, swelling resistance and crosslink density of EPDM/Bt composites were studied. The effect of in situ addition of different silane coupling agents (SCAs) on the above properties at optimum Bt loading of EPDM/Bt composite was also investigated. Thermal aging test results show that the tensile strength and tensile modulus at 100% elongation (M100) increase initially for 2 days aged composites and decrease slightly after 4 days of aging, meanwhile the elongation at break (Eb) decrease gradually with aging period as compared to the unaged composites. Upon aging, swelling resistance increase initially indicating increased crosslink density of EPDM/Bt composite due to post-curing and reduced after 4 days of aging due to crosslink destruction and EPDM chain scissioning. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4419–4427, 2013

  • Blending of Natural Rubber/Recycled Ethylene-Propylene-Diene Monomer: Cure Behaviors and Mechanical Properties
    Polymer-Plastics Technology and Engineering, 2013
    Co-Authors: Nabil Hayeemasae, Hanafi Ismail, A R Azura
    Abstract:

    In this article, blending of natural rubber with recycled ethylene-propylene-diene monomer (R-EPDM) was studied. The comparative studies of cure behaviors, mechanical properties and morphology of natural rubber/recycled ethylene-propylene-diene monomer (NR/R-EPDM) and natural rubber/ethylene-propylene-diene monomer blends (NR/EPDM) were carried out. Results indicated that the maximum torque (MH), minimum torque (ML), scorch time (ts2) and cure time (tc90) of NR/EPDM increased with increasing virgin EPDM in the weight ratio of the blend. Similar observation was also obtained for NR/R-EPDM blend except for the ML and ts2 which exhibited the opposite trend. SEM micrographs proved that the incorporation of R-EPDM up to 30 phr in the blends exhibited high roughness surface and matrix tearing line. Meanwhile, the micrographs of NR/EPDM blends showed a reduction in crack path with increasing virgin EPDM content, which led to less resistance for crack propagation and therefore, resulted in low tensile strength.

  • compounding mechanical and morphological properties of carbon black filled natural rubber recycled ethylene propylene diene monomer nr r epdm blends
    Polymer Testing, 2013
    Co-Authors: Hadeer Nabil, Hanafi Ismail, A R Azura
    Abstract:

    Abstract Blends of natural rubber/virgin Ethylene-Propylene-Diene-Monomer (NR/EPDM) and natural rubber/recycled Ethylene-Propylene-Diene-Monomer (NR/R-EPDM) were prepared. A fixed amount of carbon black (30 phr) was also incorporated. The effect of the blend ratio (90/10, 80/20, 70/30, 60/40 and 50/50 (phr/phr)) on the compounding, mechanical and morphological properties of carbon-black-filled NR/EPDM and NR/R-EPDM blends was studied. The results indicated that both the carbon-black-filled NR/EPDM and NR/R-EPDM blends exhibited a decrease in tensile strength and elongation at break for increasing weight ratio of EPDM or R-EPDM. The maximum torque (S′MH), minimum torque (S′ML), torque difference (S′MH−ML), scorch time (ts2) and cure time (tc90) of carbon-black-filled NR/EPDM or NR/R-EPDM blends increased with increasing weight ratio of virgin EPDM or R-EPDM in the blend. SEM micrographs proved that, for low weight ratios of virgin EPDM or R-EPDM, the blends exhibited high surface roughness and matrix tearing lines. The blends also showed a reduction in crack path with increasing virgin EPDM or R-EPDM content over 30 phr. This reduction in crack path could lead to less resistance to crack propagation and, therefore, low tensile strength.

  • Effects of virgin Ethylene–Propylene–Diene–Monomer and its preheating time on the properties of natural rubber/recycled Ethylene–Propylene–Diene–Monomer blends
    Materials & Design, 2013
    Co-Authors: H. Nabil, Hanafi Ismail, A R Azura
    Abstract:

    Abstract Blending of natural rubber/recycled Ethylene–Propylene–Diene–Monomer (NR/R-EPDM) blends was carried out. A fixed amount of carbon black and virgin Ethylene–Propylene–Diene–Monomer (EPDM) were also introduced into the blends. Applications of two different processing methods were carried out to improve the cure compatibility, crosslink distribution, and hence mechanical properties of the blends. Simple processing method was done by mixing the entire additives and rubbers on a laboratory-sized two-roll-mill at ambient temperature. Whereas, reactive processing method was conducted by mixing virgin EPDM, recycled EPDM and other compounding ingredients using an internal mixer, the compound was later preheated according to designated time before blending with natural rubber and carbon black. Results revealed that the enhancement of the physical and mechanical properties was significantly achieved towards preheating time of EPDM/R-EPDM blends. The improved properties in the blends suggested that the reactive processing method had led to more homogeneous blends due to a better crosslink distribution and more homogeneous carbon black distribution.

  • Compounding, mechanical and morphological properties of carbon-black-filled natural rubber/recycled Ethylene-Propylene-Diene-Monomer (NR/R-EPDM) blends
    Polymer Testing, 2013
    Co-Authors: H. Nabil, Hanafi Ismail, A R Azura
    Abstract:

    Abstract Blends of natural rubber/virgin Ethylene-Propylene-Diene-Monomer (NR/EPDM) and natural rubber/recycled Ethylene-Propylene-Diene-Monomer (NR/R-EPDM) were prepared. A fixed amount of carbon black (30 phr) was also incorporated. The effect of the blend ratio (90/10, 80/20, 70/30, 60/40 and 50/50 (phr/phr)) on the compounding, mechanical and morphological properties of carbon-black-filled NR/EPDM and NR/R-EPDM blends was studied. The results indicated that both the carbon-black-filled NR/EPDM and NR/R-EPDM blends exhibited a decrease in tensile strength and elongation at break for increasing weight ratio of EPDM or R-EPDM. The maximum torque (S′M H ), minimum torque (S′M L ), torque difference (S′M H −M L ), scorch time (ts 2 ) and cure time (tc 90 ) of carbon-black-filled NR/EPDM or NR/R-EPDM blends increased with increasing weight ratio of virgin EPDM or R-EPDM in the blend. SEM micrographs proved that, for low weight ratios of virgin EPDM or R-EPDM, the blends exhibited high surface roughness and matrix tearing lines. The blends also showed a reduction in crack path with increasing virgin EPDM or R-EPDM content over 30 phr. This reduction in crack path could lead to less resistance to crack propagation and, therefore, low tensile strength.

H. Nabil - One of the best experts on this subject based on the ideXlab platform.

  • Thermal stability and aging characteristics of (natural rubber)/(waste ethylene-propylene-diene monomer terpolymer) blends
    Journal of Vinyl and Additive Technology, 2014
    Co-Authors: H. Nabil, H. Ismail, A R Azura
    Abstract:

    Comparative studies of the thermogravimetric analysis and thermo-oxidative aging of (natural rubber)/(waste ethylene-propylene-diene monomer terpolymer) (NR/W-EPDM) and (natural rubber)/(ethylene-propylene-diene monomer terpolymer) (NR/EPDM) blends were carried out. The blends were prepared at five different blend ratios (90/10, 80/20, 70/30, 60/40, and 50/50) on a two-roll mill. As the pure EPDM or W-EPDM content in the blends increased, their thermal stability also increased. The thermo-oxidative aging of these blends was done at 100°C for 48 h. Afterwards, the NR/EPDM blends exhibited better retention of properties than the NR/W-EPDM blends. Crosslink density measurements of the blends after thermal aging indicated that higher crosslink density was obtained from a higher content of EPDM or W-EPDM, a result which might be due to the high rate of radical termination leading to crosslinks in the bulk of the polymer. J. VINYL ADDIT. TECHNOL., 20:99–107, 2014. © 2014 Society of Plastics Engineers

  • Effects of virgin Ethylene–Propylene–Diene–Monomer and its preheating time on the properties of natural rubber/recycled Ethylene–Propylene–Diene–Monomer blends
    Materials & Design, 2013
    Co-Authors: H. Nabil, Hanafi Ismail, A R Azura
    Abstract:

    Abstract Blending of natural rubber/recycled Ethylene–Propylene–Diene–Monomer (NR/R-EPDM) blends was carried out. A fixed amount of carbon black and virgin Ethylene–Propylene–Diene–Monomer (EPDM) were also introduced into the blends. Applications of two different processing methods were carried out to improve the cure compatibility, crosslink distribution, and hence mechanical properties of the blends. Simple processing method was done by mixing the entire additives and rubbers on a laboratory-sized two-roll-mill at ambient temperature. Whereas, reactive processing method was conducted by mixing virgin EPDM, recycled EPDM and other compounding ingredients using an internal mixer, the compound was later preheated according to designated time before blending with natural rubber and carbon black. Results revealed that the enhancement of the physical and mechanical properties was significantly achieved towards preheating time of EPDM/R-EPDM blends. The improved properties in the blends suggested that the reactive processing method had led to more homogeneous blends due to a better crosslink distribution and more homogeneous carbon black distribution.

  • Compounding, mechanical and morphological properties of carbon-black-filled natural rubber/recycled Ethylene-Propylene-Diene-Monomer (NR/R-EPDM) blends
    Polymer Testing, 2013
    Co-Authors: H. Nabil, Hanafi Ismail, A R Azura
    Abstract:

    Abstract Blends of natural rubber/virgin Ethylene-Propylene-Diene-Monomer (NR/EPDM) and natural rubber/recycled Ethylene-Propylene-Diene-Monomer (NR/R-EPDM) were prepared. A fixed amount of carbon black (30 phr) was also incorporated. The effect of the blend ratio (90/10, 80/20, 70/30, 60/40 and 50/50 (phr/phr)) on the compounding, mechanical and morphological properties of carbon-black-filled NR/EPDM and NR/R-EPDM blends was studied. The results indicated that both the carbon-black-filled NR/EPDM and NR/R-EPDM blends exhibited a decrease in tensile strength and elongation at break for increasing weight ratio of EPDM or R-EPDM. The maximum torque (S′M H ), minimum torque (S′M L ), torque difference (S′M H −M L ), scorch time (ts 2 ) and cure time (tc 90 ) of carbon-black-filled NR/EPDM or NR/R-EPDM blends increased with increasing weight ratio of virgin EPDM or R-EPDM in the blend. SEM micrographs proved that, for low weight ratios of virgin EPDM or R-EPDM, the blends exhibited high surface roughness and matrix tearing lines. The blends also showed a reduction in crack path with increasing virgin EPDM or R-EPDM content over 30 phr. This reduction in crack path could lead to less resistance to crack propagation and, therefore, low tensile strength.

Yongqing Zhao - One of the best experts on this subject based on the ideXlab platform.

Xiaogang Li - One of the best experts on this subject based on the ideXlab platform.

  • degradation characterization of ethylene propylene diene monomer epdm rubber in artificial weathering environment
    Journal of Failure Analysis and Prevention, 2010
    Co-Authors: Quanlin Zhao, Jianwen Hu, Xiaogang Li, Zhengfang Ye
    Abstract:

    Ethylene-propylene-diene monomer containing 5-ethylidene-2-norbornene as diene was exposed to artificial weathering environment produced by a xenon lamp light exposure and weathering equipment for different periods of time. The changes of surface color and mechanical properties were monitored by spectrophotometer, computer-controlled tensile testing and hardness measurements. Crosslink density of ethylene-propylene-diene monomer specimens was measured by the solvent swell method. The results showed that the surface of ethylene-propylene-diene monomer became yellower due to the form of carbonyl group. The degradation process proceeded predominantly via cross-linking. With increase in crosslink density, the tensile strength increased and the elongation at fracture decreased.

  • degradation evaluation of ethylene propylene diene monomer epdm rubber in artificial weathering environment by principal component analysis
    Materials Letters, 2009
    Co-Authors: Quanlin Zhao, Xiaogang Li
    Abstract:

    Abstract Artificial weathering tests on ethylene–propylene–diene monomer (EPDM) containing 5-ethylidene-2-norbornene (ENB) as diene were conducted in a xenon lamp light exposure and weathering equipment for different time periods. Principal component analysis (PCA) was used to evaluate the 12 degradation parameters of EPDM including surface properties, crosslink density and mechanical properties. The results showed that the combined evaluating parameter Z of EPDM degradation increased quickly in the first 12 days of exposure and then leveled off. After 45 days, it began to increase rapidly again. Among the 12 degradation parameters, the crosslink density is strongly associated with tensile stress at 300% elongation and tear strength. The surface tension is also well correlated with the color aberration.

  • Degradation evaluation of ethylene–propylene–diene monomer (EPDM) rubber in artificial weathering environment by principal component analysis
    Materials Letters, 2009
    Co-Authors: Quanlin Zhao, Xiaogang Li
    Abstract:

    Abstract Artificial weathering tests on ethylene–propylene–diene monomer (EPDM) containing 5-ethylidene-2-norbornene (ENB) as diene were conducted in a xenon lamp light exposure and weathering equipment for different time periods. Principal component analysis (PCA) was used to evaluate the 12 degradation parameters of EPDM including surface properties, crosslink density and mechanical properties. The results showed that the combined evaluating parameter Z of EPDM degradation increased quickly in the first 12 days of exposure and then leveled off. After 45 days, it began to increase rapidly again. Among the 12 degradation parameters, the crosslink density is strongly associated with tensile stress at 300% elongation and tear strength. The surface tension is also well correlated with the color aberration.

  • aging of ethylene propylene diene monomer epdm in artificial weathering environment
    Polymer Degradation and Stability, 2007
    Co-Authors: Quanlin Zhao, Xiaogang Li
    Abstract:

    Abstract Ethylene–propylene–diene monomer (EPDM) containing ENB as diene was exposed to artificial weathering environment for different periods of time. The changes of appearance, morphology, mechanical properties and chemical structures were monitored by spectrophotometer, glossmeter, microscope, computer-controlled tensile testing, hardness measurements and Fourier Transform Infrared (FTIR) spectroscopy. Crosslink density of EPDM specimens was measured by the solvent swell method. The results showed that the surface of EPDM became redder, yellower and lighter in the first stage of aging and then remained almost unchanged. The specular gloss reached a maximum when the sample was exposed for 18 days and then decreased. The aging process proceeded predominantly via crosslinking. The tensile strength increased with increase in crosslink density up to an optimum value and thereafter decreased with further increase in crosslink density. FTIR spectra confirmed the formation of carbonyl groups in an artificial weathering environment.

  • Aging of ethylene–propylene–diene monomer (EPDM) in artificial weathering environment
    Polymer Degradation and Stability, 2007
    Co-Authors: Quanlin Zhao, Xiaogang Li
    Abstract:

    Abstract Ethylene–propylene–diene monomer (EPDM) containing ENB as diene was exposed to artificial weathering environment for different periods of time. The changes of appearance, morphology, mechanical properties and chemical structures were monitored by spectrophotometer, glossmeter, microscope, computer-controlled tensile testing, hardness measurements and Fourier Transform Infrared (FTIR) spectroscopy. Crosslink density of EPDM specimens was measured by the solvent swell method. The results showed that the surface of EPDM became redder, yellower and lighter in the first stage of aging and then remained almost unchanged. The specular gloss reached a maximum when the sample was exposed for 18 days and then decreased. The aging process proceeded predominantly via crosslinking. The tensile strength increased with increase in crosslink density up to an optimum value and thereafter decreased with further increase in crosslink density. FTIR spectra confirmed the formation of carbonyl groups in an artificial weathering environment.