The Experts below are selected from a list of 282 Experts worldwide ranked by ideXlab platform

Noor Najmi Bonnia - One of the best experts on this subject based on the ideXlab platform.

  • environmental stress cracking Resistance escr of rubber toughened polyester kenaf composites under active environment
    International Conference Key Engineering Materials, 2013
    Co-Authors: N S Shuhaimen, Noor Najmi Bonnia, Aein Afina Redzuan, M R H Mohamed
    Abstract:

    This study was undertaken to investigate mechanical and morphological properties of rubber toughened polyester composite filled with kenaf and was exposed in varying natural weathering and difference environmental condition (Artificial Sea Water (SW), Distilled Water (DS), Environment Exposure (EX) and Soil Exposure (SL)). Rubber-toughened polyester-kenaf fibre composites were prepared by adding 25% of kenaf fibre in unsaturated polyester resin and cross linked with a mixture of methyl ethylketone peroxide and cobalt octanoate. Three percent (3%) of liquid natural rubber (LNR) were added as a toughening agent. The sample was prepared using compression molding technique. It was found that the samples that being immersed in seawater (SW) had lower mechanical properties values as compare with other conditions. The value of flexural modulus and flexural strength were decrease by 35.9 % , 12.5% but the value of impact strength had slightly increase by 34% .The microstructures of the composites fracture surface were examined using a scanning electron microscope (SEM).

  • mechanical properties and environmental stress cracking Resistance of rubber toughened polyester clay composite
    Advanced Materials Research, 2012
    Co-Authors: Noor Najmi Bonnia, Sahrim Ahmad, Siti Norasmah Surip, S S Nurul, H N Azlina, Hazleen Anuar
    Abstract:

    Crosslinked polyester clay nanocomposites were prepared by dispersing originically modified montmorillonite in prepromoted polyester resin and subsequently crosslinked using methyl ethyl ketone peroxide catalyst at different clay concentration. Cure process and the mechanical properties of rubber toughened polyester clay composite have been studied. Rubber toughened thermoset polyester composite were prepared by adding 3 per hundred rubber (phr) of liquid natural rubber (LNR) was used in the mixing of producing this composite. Modification of polyester matrix was done due to the brittle problem of polyester composite. Addition of LNR will increase the toughness of composite and produce ductile polyester. Two types of composites were produced which is clay-lnr polyester composite and clay polyester composite. Addition of liquid natural rubber significantly increased the impact strength and flexural properties. Result shows that addition of 6% of clay-lnr composite give good properties on impact, strength and flexural. From the ESCR test, both composites showed good Resistance to environmental.

  • Mechanical Properties and Environmental Stress Cracking Resistance of Rubber Toughened Polyester/Clay Composite
    Advanced Materials Research, 2012
    Co-Authors: Noor Najmi Bonnia, Sahrim Ahmad, Siti Norasmah Surip, S S Nurul, H N Azlina, Hazleen Anuar
    Abstract:

    Crosslinked polyester clay nanocomposites were prepared by dispersing originically modified montmorillonite in prepromoted polyester resin and subsequently crosslinked using methyl ethyl ketone peroxide catalyst at different clay concentration. Cure process and the mechanical properties of rubber toughened polyester clay composite have been studied. Rubber toughened thermoset polyester composite were prepared by adding 3 per hundred rubber (phr) of liquid natural rubber (LNR) was used in the mixing of producing this composite. Modification of polyester matrix was done due to the brittle problem of polyester composite. Addition of LNR will increase the toughness of composite and produce ductile polyester. Two types of composites were produced which is clay-lnr polyester composite and clay polyester composite. Addition of liquid natural rubber significantly increased the impact strength and flexural properties. Result shows that addition of 6% of clay-lnr composite give good properties on impact, strength and flexural. From the ESCR test, both composites showed good Resistance to environmental.

  • Polyester-Kenaf Composites: Effects of Alkali Fiber Treatment and Toughening of Matrix Using Liquid Natural Rubber
    Journal of Composite Materials, 2010
    Co-Authors: Sahrim Ahmad, Ismail Zainol, Rozaidi Rasid, Noor Najmi Bonnia, Abdullah Al Mamun, Andrzej K Bledzki
    Abstract:

    In this study, polyesterkenaf fiber composites were prepared by adding various percentages of kenaf fiber in unsaturated polyester resin and subse- quently cross-linked using methyl ethyl ketone peroxide and the accelerator cobalt octanoate. Liquid natural rubber (LNR) (3%) was added as a toughening agent. Kenaf fibers were treated with sodium hydroxide solution to improve the interfacial bonding between the fiber and the matrix. The mechanical properties of the com- posites were evaluated by impact and flexural testing. Environmental stress cracking Resistance (ESCR) of composites in acid and base medium was also studied. Bonding mechanisms were assessed by scanning electron microscope and Fourier transform infrared analysis. It was found that the addition of LNR increased the impact strength and fracture toughness. Alkali fiber treatment was found to provide better impact and flexural strengths to the composites. Measurement of ESCR shows that the composite with acid medium has the fastest diffusion rate, followed by that with base medium, and then without medium.

  • Mechanical properties and environmental stress cracking Resistance of rubber toughened polyester/kenaf composite
    Express Polymer Letters, 2010
    Co-Authors: Noor Najmi Bonnia, Ismail Zainol, Sahrim Ahmad, Abdullah Al Mamun, Andrzej K Bledzki
    Abstract:

    In this study rubber-toughened polyester-kenaf fibre composites were prepared by adding various percentages of kenaf fibre in unsaturated polyester resin and subsequently cross linked using a mixture of organic peroxide methyl ethyl ketone and cobalt octanoate. Three percent (3%) of liquid natural rubber (LNR) were added as a toughening agent. The mechanical properties of the composites were evaluated by impact and flexural testing. Environmental stress cracking Resistance (ESCR) of polyester-kenaf composite in acid and base medium was also studied. It was found that the addition of LNR increased impact strength by about 66% and flexural strength by 70%. Measurement of ESCR shows that the composite has the fastest diffusion rate in acid medium, followed by that in base medium and then without medium. Bonding mechanisms were assessed by scanning electron microscope and FTIR analysis

Andrzej K Bledzki - One of the best experts on this subject based on the ideXlab platform.

  • Polyester-Kenaf Composites: Effects of Alkali Fiber Treatment and Toughening of Matrix Using Liquid Natural Rubber
    Journal of Composite Materials, 2010
    Co-Authors: Sahrim Ahmad, Ismail Zainol, Rozaidi Rasid, Noor Najmi Bonnia, Abdullah Al Mamun, Andrzej K Bledzki
    Abstract:

    In this study, polyesterkenaf fiber composites were prepared by adding various percentages of kenaf fiber in unsaturated polyester resin and subse- quently cross-linked using methyl ethyl ketone peroxide and the accelerator cobalt octanoate. Liquid natural rubber (LNR) (3%) was added as a toughening agent. Kenaf fibers were treated with sodium hydroxide solution to improve the interfacial bonding between the fiber and the matrix. The mechanical properties of the com- posites were evaluated by impact and flexural testing. Environmental stress cracking Resistance (ESCR) of composites in acid and base medium was also studied. Bonding mechanisms were assessed by scanning electron microscope and Fourier transform infrared analysis. It was found that the addition of LNR increased the impact strength and fracture toughness. Alkali fiber treatment was found to provide better impact and flexural strengths to the composites. Measurement of ESCR shows that the composite with acid medium has the fastest diffusion rate, followed by that with base medium, and then without medium.

  • Mechanical properties and environmental stress cracking Resistance of rubber toughened polyester/kenaf composite
    Express Polymer Letters, 2010
    Co-Authors: Noor Najmi Bonnia, Ismail Zainol, Sahrim Ahmad, Abdullah Al Mamun, Andrzej K Bledzki
    Abstract:

    In this study rubber-toughened polyester-kenaf fibre composites were prepared by adding various percentages of kenaf fibre in unsaturated polyester resin and subsequently cross linked using a mixture of organic peroxide methyl ethyl ketone and cobalt octanoate. Three percent (3%) of liquid natural rubber (LNR) were added as a toughening agent. The mechanical properties of the composites were evaluated by impact and flexural testing. Environmental stress cracking Resistance (ESCR) of polyester-kenaf composite in acid and base medium was also studied. It was found that the addition of LNR increased impact strength by about 66% and flexural strength by 70%. Measurement of ESCR shows that the composite has the fastest diffusion rate in acid medium, followed by that in base medium and then without medium. Bonding mechanisms were assessed by scanning electron microscope and FTIR analysis

Mei Liang - One of the best experts on this subject based on the ideXlab platform.

  • investigations of environmental stress cracking Resistance of ldpe uhmwpe and ldpe eva blends
    Plastics Rubber and Composites, 2015
    Co-Authors: Zhengguang Heng, Yang Chen, Mei Liang
    Abstract:

    Low density polyethylene (LDPE)/ultrahigh molecular weight polyethylene (UHMWPE) and LDPE/poly(ethylene-co-vinylacetate) (EVA) blends were tested and compared with respect to their environmental stress cracking Resistance (ESCR) using the Bell telephone test. The time to failure in the ESCR test improved with increasing UHMWPE and EVA content, and considerable improvements were produced when an UHMWPE weight fraction of 0.4 and EVA weight fraction of 0.03 were used. Thermal and morphological studies were conducted, and a relationship between morphological features and composition was established. Furthermore, the failed specimens were further characterised by scanning electron microscopy and fractographic methodology to investigate the failure mechanism for ESCR samples.

  • Investigations of environmental stress cracking Resistance of LDPE/UHMWPE and LDPE/EVA blends
    Plastics Rubber and Composites, 2015
    Co-Authors: Zhengguang Heng, Yang Chen, Mei Liang
    Abstract:

    Low density polyethylene (LDPE)/ultrahigh molecular weight polyethylene (UHMWPE) and LDPE/poly(ethylene-co-vinylacetate) (EVA) blends were tested and compared with respect to their environmental stress cracking Resistance (ESCR) using the Bell telephone test. The time to failure in the ESCR test improved with increasing UHMWPE and EVA content, and considerable improvements were produced when an UHMWPE weight fraction of 0.4 and EVA weight fraction of 0.03 were used. Thermal and morphological studies were conducted, and a relationship between morphological features and composition was established. Furthermore, the failed specimens were further characterised by scanning electron microscopy and fractographic methodology to investigate the failure mechanism for ESCR samples.

  • Structural and rheological property relationship of bimodal polyethylene with improved environment stress cracking Resistance
    Polymer Science Series A, 2014
    Co-Authors: Yang Chen, Mei Liang, Yanzhou Lei, Huawei Zou, Ya Cao
    Abstract:

    Five bimodal polyethylene samples with different molecular parameters were studied in order to understand the incidence of molecular architecture on the environment stress cracking Resistance (ESCR). The results showed that the tensile strain hardening stiffness at low strain rate was shown to be a fast and reliable indicator for evaluating ESCR of polyethylene. The reduction of chain dimension from phase separation would lead to the decrease of the possibility for a molecular in melt to form a tie molecular but an increasing number of short chain branch content was shown to increases strain hardening stiffness or tie chains. Physical chain entanglements were established as another source of inter-lamellar linkages that contribute to ESCR of polyethylene. Within the similar branch content and no phase separation, due to an increasing in plateau modulus was shown to increases hardening stiffness or ESCR of resins.

  • investigations of environmental stress cracking Resistance of hdpe uhmwpe and ldpe uhmwpe blends
    Journal of Polymer Research, 2013
    Co-Authors: Yang Chen, Shengtai Zhou, Mei Liang
    Abstract:

    HDPE/UHMWPE and LDPE/UHMWPE blends were prepared and the environmental stress cracking Resistance (ESCR) was compared using the Bell-telephone test. The time to failure in the ESCR test improved with increasing UHMWPE content, and considerable improvements were both produced when an UHMWPE weight fraction of 0.4 was used. Whereas LDPE/UHMWPE blend yield a higher improvement in stress cracking Resistance compared to that of HDPE/UHMWPE blend. Thermal, morphological and mechanical studies were conducted and a relationship between morphological features and composition was established. Furthermore, the failed specimens were further characterized by scanning electron microscopy and fractographic methodology to investigate the failure mechanism for ESCR samples.

  • Investigations of environmental stress cracking Resistance of HDPE/UHMWPE and LDPE/UHMWPE blends
    Journal of Polymer Research, 2013
    Co-Authors: Yang Chen, Shengtai Zhou, Mei Liang
    Abstract:

    HDPE/UHMWPE and LDPE/UHMWPE blends were prepared and the environmental stress cracking Resistance (ESCR) was compared using the Bell-telephone test. The time to failure in the ESCR test improved with increasing UHMWPE content, and considerable improvements were both produced when an UHMWPE weight fraction of 0.4 was used. Whereas LDPE/UHMWPE blend yield a higher improvement in stress cracking Resistance compared to that of HDPE/UHMWPE blend. Thermal, morphological and mechanical studies were conducted and a relationship between morphological features and composition was established. Furthermore, the failed specimens were further characterized by scanning electron microscopy and fractographic methodology to investigate the failure mechanism for ESCR samples.

Sahrim Ahmad - One of the best experts on this subject based on the ideXlab platform.

  • mechanical properties of hybrid glass kenaf fibre reinforced epoxy composite with matrix modification using liquid epoxidised natural rubber
    Journal of Reinforced Plastics and Composites, 2015
    Co-Authors: Yusri Helmi Muhammad, Sahrim Ahmad, Abdullah Al Mamun, Mimi Azlina Abu Bakar, Hans P Heim
    Abstract:

    The hybridisation of natural fibre with glass fibre provides a method to improve the mechanical properties instead of using the natural fibres alone. This research is focused on the hybridisation of glass/kenaf fibre with the addition of liquid epoxidised natural rubber to enhance the desired mechanical properties of the composite by reducing the synthetic fibre usage and encourage the natural fibre consumption. Liquid epoxidised natural rubber was added to the epoxy matrix in order to improve its mechanical properties whilst E-glass fibre and kenaf bast fibre were used as the reinforcement in the composite. Liquid epoxidised natural rubber (3%) was added as a toughening agent. Two types of kenaf fibre were prepared – untreated and treated with 6% NaOH – whilst the glass fibre was treated using a silane coupling agent. The flexural test, Izod impact test, environmental stress cracking Resistance analysis and scanning electron microscopy analysis were performed to determine the effect of fibre treatment an...

  • mechanical properties and environmental stress cracking Resistance of rubber toughened polyester clay composite
    Advanced Materials Research, 2012
    Co-Authors: Noor Najmi Bonnia, Sahrim Ahmad, Siti Norasmah Surip, S S Nurul, H N Azlina, Hazleen Anuar
    Abstract:

    Crosslinked polyester clay nanocomposites were prepared by dispersing originically modified montmorillonite in prepromoted polyester resin and subsequently crosslinked using methyl ethyl ketone peroxide catalyst at different clay concentration. Cure process and the mechanical properties of rubber toughened polyester clay composite have been studied. Rubber toughened thermoset polyester composite were prepared by adding 3 per hundred rubber (phr) of liquid natural rubber (LNR) was used in the mixing of producing this composite. Modification of polyester matrix was done due to the brittle problem of polyester composite. Addition of LNR will increase the toughness of composite and produce ductile polyester. Two types of composites were produced which is clay-lnr polyester composite and clay polyester composite. Addition of liquid natural rubber significantly increased the impact strength and flexural properties. Result shows that addition of 6% of clay-lnr composite give good properties on impact, strength and flexural. From the ESCR test, both composites showed good Resistance to environmental.

  • Mechanical Properties and Environmental Stress Cracking Resistance of Rubber Toughened Polyester/Clay Composite
    Advanced Materials Research, 2012
    Co-Authors: Noor Najmi Bonnia, Sahrim Ahmad, Siti Norasmah Surip, S S Nurul, H N Azlina, Hazleen Anuar
    Abstract:

    Crosslinked polyester clay nanocomposites were prepared by dispersing originically modified montmorillonite in prepromoted polyester resin and subsequently crosslinked using methyl ethyl ketone peroxide catalyst at different clay concentration. Cure process and the mechanical properties of rubber toughened polyester clay composite have been studied. Rubber toughened thermoset polyester composite were prepared by adding 3 per hundred rubber (phr) of liquid natural rubber (LNR) was used in the mixing of producing this composite. Modification of polyester matrix was done due to the brittle problem of polyester composite. Addition of LNR will increase the toughness of composite and produce ductile polyester. Two types of composites were produced which is clay-lnr polyester composite and clay polyester composite. Addition of liquid natural rubber significantly increased the impact strength and flexural properties. Result shows that addition of 6% of clay-lnr composite give good properties on impact, strength and flexural. From the ESCR test, both composites showed good Resistance to environmental.

  • Polyester-Kenaf Composites: Effects of Alkali Fiber Treatment and Toughening of Matrix Using Liquid Natural Rubber
    Journal of Composite Materials, 2010
    Co-Authors: Sahrim Ahmad, Ismail Zainol, Rozaidi Rasid, Noor Najmi Bonnia, Abdullah Al Mamun, Andrzej K Bledzki
    Abstract:

    In this study, polyesterkenaf fiber composites were prepared by adding various percentages of kenaf fiber in unsaturated polyester resin and subse- quently cross-linked using methyl ethyl ketone peroxide and the accelerator cobalt octanoate. Liquid natural rubber (LNR) (3%) was added as a toughening agent. Kenaf fibers were treated with sodium hydroxide solution to improve the interfacial bonding between the fiber and the matrix. The mechanical properties of the com- posites were evaluated by impact and flexural testing. Environmental stress cracking Resistance (ESCR) of composites in acid and base medium was also studied. Bonding mechanisms were assessed by scanning electron microscope and Fourier transform infrared analysis. It was found that the addition of LNR increased the impact strength and fracture toughness. Alkali fiber treatment was found to provide better impact and flexural strengths to the composites. Measurement of ESCR shows that the composite with acid medium has the fastest diffusion rate, followed by that with base medium, and then without medium.

  • Mechanical properties and environmental stress cracking Resistance of rubber toughened polyester/kenaf composite
    Express Polymer Letters, 2010
    Co-Authors: Noor Najmi Bonnia, Ismail Zainol, Sahrim Ahmad, Abdullah Al Mamun, Andrzej K Bledzki
    Abstract:

    In this study rubber-toughened polyester-kenaf fibre composites were prepared by adding various percentages of kenaf fibre in unsaturated polyester resin and subsequently cross linked using a mixture of organic peroxide methyl ethyl ketone and cobalt octanoate. Three percent (3%) of liquid natural rubber (LNR) were added as a toughening agent. The mechanical properties of the composites were evaluated by impact and flexural testing. Environmental stress cracking Resistance (ESCR) of polyester-kenaf composite in acid and base medium was also studied. It was found that the addition of LNR increased impact strength by about 66% and flexural strength by 70%. Measurement of ESCR shows that the composite has the fastest diffusion rate in acid medium, followed by that in base medium and then without medium. Bonding mechanisms were assessed by scanning electron microscope and FTIR analysis

Yang Chen - One of the best experts on this subject based on the ideXlab platform.

  • investigations of environmental stress cracking Resistance of ldpe uhmwpe and ldpe eva blends
    Plastics Rubber and Composites, 2015
    Co-Authors: Zhengguang Heng, Yang Chen, Mei Liang
    Abstract:

    Low density polyethylene (LDPE)/ultrahigh molecular weight polyethylene (UHMWPE) and LDPE/poly(ethylene-co-vinylacetate) (EVA) blends were tested and compared with respect to their environmental stress cracking Resistance (ESCR) using the Bell telephone test. The time to failure in the ESCR test improved with increasing UHMWPE and EVA content, and considerable improvements were produced when an UHMWPE weight fraction of 0.4 and EVA weight fraction of 0.03 were used. Thermal and morphological studies were conducted, and a relationship between morphological features and composition was established. Furthermore, the failed specimens were further characterised by scanning electron microscopy and fractographic methodology to investigate the failure mechanism for ESCR samples.

  • Investigations of environmental stress cracking Resistance of LDPE/UHMWPE and LDPE/EVA blends
    Plastics Rubber and Composites, 2015
    Co-Authors: Zhengguang Heng, Yang Chen, Mei Liang
    Abstract:

    Low density polyethylene (LDPE)/ultrahigh molecular weight polyethylene (UHMWPE) and LDPE/poly(ethylene-co-vinylacetate) (EVA) blends were tested and compared with respect to their environmental stress cracking Resistance (ESCR) using the Bell telephone test. The time to failure in the ESCR test improved with increasing UHMWPE and EVA content, and considerable improvements were produced when an UHMWPE weight fraction of 0.4 and EVA weight fraction of 0.03 were used. Thermal and morphological studies were conducted, and a relationship between morphological features and composition was established. Furthermore, the failed specimens were further characterised by scanning electron microscopy and fractographic methodology to investigate the failure mechanism for ESCR samples.

  • Structural and rheological property relationship of bimodal polyethylene with improved environment stress cracking Resistance
    Polymer Science Series A, 2014
    Co-Authors: Yang Chen, Mei Liang, Yanzhou Lei, Huawei Zou, Ya Cao
    Abstract:

    Five bimodal polyethylene samples with different molecular parameters were studied in order to understand the incidence of molecular architecture on the environment stress cracking Resistance (ESCR). The results showed that the tensile strain hardening stiffness at low strain rate was shown to be a fast and reliable indicator for evaluating ESCR of polyethylene. The reduction of chain dimension from phase separation would lead to the decrease of the possibility for a molecular in melt to form a tie molecular but an increasing number of short chain branch content was shown to increases strain hardening stiffness or tie chains. Physical chain entanglements were established as another source of inter-lamellar linkages that contribute to ESCR of polyethylene. Within the similar branch content and no phase separation, due to an increasing in plateau modulus was shown to increases hardening stiffness or ESCR of resins.

  • investigations of environmental stress cracking Resistance of hdpe eva and ldpe eva blends
    Journal of Applied Polymer Science, 2014
    Co-Authors: Yang Chen
    Abstract:

    HDPE/poly(ethylene-co-vinylacetate) (EVA) and low-density polyethylene (LDPE)/EVA blends were tested and compared with respect to their environmental stress cracking Resistance (ESCR) using the Bell-telephone test. The time to failure in the ESCR test improves with increasing EVA content, and considerable improvements were produced for LDPE/EVA blends while small improvements were observed for HDPE/EVA blends. Thermal, rheological, mechanical, and morphological studies were conducted which established a quantitative relationship between morphological features and composition. Furthermore, the failed specimens were further characterized by scanning electron microscopy and fractographic methodology to investigate the failure mechanism for ESCR samples. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39880.

  • Investigations of environmental stress cracking Resistance of HDPE/EVA and LDPE/EVA blends
    Journal of Applied Polymer Science, 2013
    Co-Authors: Yang Chen
    Abstract:

    HDPE/poly(ethylene-co-vinylacetate) (EVA) and low-density polyethylene (LDPE)/EVA blends were tested and compared with respect to their environmental stress cracking Resistance (ESCR) using the Bell-telephone test. The time to failure in the ESCR test improves with increasing EVA content, and considerable improvements were produced for LDPE/EVA blends while small improvements were observed for HDPE/EVA blends. Thermal, rheological, mechanical, and morphological studies were conducted which established a quantitative relationship between morphological features and composition. Furthermore, the failed specimens were further characterized by scanning electron microscopy and fractographic methodology to investigate the failure mechanism for ESCR samples. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39880.