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Polyolefins - Volume:9 Issue: 1, Winter-Spring 2022

Polyolefins Journal
Volume:9 Issue: 1, Winter-Spring 2022

  • تاریخ انتشار: 1400/10/19
  • تعداد عناوین: 7
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  • Mehdi Nekoomanesh Page 0
  • Raid Banat *, Malek Aljnaid, Manal Al Rawashdeh Pages 1-14

    Mechanical and physical properties of various weigh percentages (0% - 40%) of olive pomace flour (OPF)-loaded linear low density polyethylene (LLDPE) in the presence of 0%, 5% and 10% coupling agent (C) were formulated and studied. Extrusion and hot press processing techniques were used to fabricate OPF/LLDPE composites. Tensile stress at yield increased by 20% with the increasing of the filler loading up to 20%; and marginally increased in the presence of the C. Whereas, the decline in the tensile strain at yield of the polymer composite improved with the increase in the C content. The modulus increased from 631 MPa for the neat LLDPE to 680, 808 and 700 MPa for the composites filled by 5%, 10% and 20% filler content, respectively. Whereas, a decrease in the given modulus (550 MPa) was observed at 40% filler loading. The modulus has shown a successive improvement upon the addition of the C with values not less than 800 MPa. The impact strength decreased with the increase in filler loading from 119 kJ/m2 for the neat LLDPE to 81, 43, 27 and 16 kJ/m2 for the 5%, 10%, 20% and 40% OPF/LLDPE samples, respectively. On the contrary, 10% C addition improved the impact strength of the composite by two folds in the case of 10 - 40% filler inclusion. The scanning electron microscopy (SEM) illustrations proved the mechanical performance of various bio-composite formulations. Water absorption of the bio-composite increased with the OPF loading, from 0.73% for the neat LLDPE to 2.6% for 40% OPF-filled polymer composite, and decreased upon increasing the C content with an average of 1.4% for all composites. Formulated by mixing cellulosic-based material OPF and LLDPE, the bio-composite demonstrated compatible physical properties and can be used as an already available cellulosic filler for the bio-composite materials.

    Keywords: Olive pomace flour, LLDPE, Coupling Agent, bio-composite, mechanical & physical properties
  • Mohamad Hafizi Zakria *, Mohd Ghazali Mohd Nawawi, Mohd Rizal Abdul Rahman Pages 15-24
    The study was conducted in the actual world-scale olefin plant with a focus on measuring the impact of identified controlled variables at the steam cracker furnace towards the propylene yield. Surface response analysis was conducted in the Minitab software version 20 using the historical data after the clearance of both the outliers and residuals to ensure the analysis was conducted as normal data. Surface response analysis is a robust mathematical and statistical approach that is having a good potential to be systematically utilized in the actual large-scale olefin plant as an alternative to the expensive olefin simulation software for process monitoring. The analysis was conducted to forecast the maximum propylene yield in the studied plant with careful consideration to select only significant variables, represented by a variance inflation factor (VIF) <10 and p-value <0.05 in the analysis of variance (ANOVA) table. The final model successfully concluded that propylene yield in the studied plant was contributed by the factors of 0.00496, 0.00204, and -3.96 of hearth burner flow, dilution steam flow, and naphtha feed flow respectively. The response optimizer also suggested that the propylene yield from naphtha pyrolysis cracking in the studied plant could be maximized at 11.47% with the control setting at 10,004.36 kg/hr of hearth burner flow, 40,960 kg/hr of dilution steam flow, and 63.50 t/hr of naphtha feed flow.
    Keywords: Response surface methodology, Olefin Process, statistical analysis, minitab, ANOVA
  • Ivan Kuryndin, Sergei Kostromin, Rustam Mamalimov, Anton Chervov, Andrei Grebennikov, Sergei Bronnikov * Pages 25-31
    Swelling of high-density polyethylene (PE) in organic solvents, orthodichlorobenzene and orthoxylene, was investigated. The swelling kinetics of the PE specimen was described by the first-order equation. For the first time, the PE specimen swelling rate constant was shown to decrease with increasing thickness of the specimens. The equilibrium swelling of the PE specimen was evaluated. It was found that equilibrium swelling is independent of the thickness of specimens. It was shown that storage of polyethylene specimens in organic solvents changes its mechanical properties (tensile strength, Young’s modulus, and elongation-at-break) due to polymer plasticization. We have shown that the increase in flexibility and elongation-at-break after relatively short-term immersion of PE samples in these organic solvents is significant. However, the tensile strength of swollen specimens remains high enough. The interaction between polymer chains and solvent molecules was not detected. The results obtained are important for the design and operation of PE coatings and PE products, such as pipes, tanks, and other accessories exposed to oil products.
    Keywords: High-density polyethylene, organic solvents, swelling, mechanical properties, FTIR spectroscopy
  • Nanoth Rasana *, Karingamanna Jayanarayanan Pages 33-43
    Nano, micro and hybrid filler-reinforced polypropylene (PP) composites were prepared via melt compounding technique using a twin screw extruder. The nano scale MWCNTs and micro scale glass fibers were used as reinforcements. In addition to the individual effect of nano and micro scale reinforcements in virgin PP, the dual effect of multiscale (MWCNT/glass fiber) fillers was also elucidated. Morphological images revealed the effectiveness of dispersion of the fillers in the matrix and it was observed that the functionalized composites showed increased filler dispersion. The static mechanical properties of the non-functionalized and functionalized samples were compared and the hybrid composite with 2 wt.% MWCNTs showed the highest tensile strength without modulus reduction. The strong bonding between carboxyl-treated MWCNTs and maleic anhydride-grafted PP was well revealed in the FTIR spectra. In hybrid composites, the effect of silane-treated glass fibers was revealed and the siloxane linkages occurred between the glass fiber surface and silanol groups were confirmed by the FTIR spectra.
    Keywords: MWCNTs, multiscale, FTIR, functionalization, hybrid composites
  • Mariana Del Valle Bernard, Verónica Nicolau *, Miriam Strumia Pages 45-60
    Industrially used polymers derived from fossil fuels have a negative environmental impact when being disposed of. They could be efficientlyreplaced by natural polymers, which are potentially degradable and which can match or even surpass them in mechanical performance. In this work, a rigid thermosetting polymer is obtained by copolymerization of maleinated acrylated epoxidized soybean oil (MAESO) with styrene (St). MAESO is synthetized by epoxidation, acrylation and maleinization from industrial soybean oil (SO). Resin characterization is performed using FT-IR, 1H NMR and SEC, while copolymer characterization includes a mechanical test, degradation test and SEM. The aim of this work is the replacement of unsaturated polyester (UP) and the optimization of the SO modificationreaction in MAESO. The replacement of UP by 25, 50 and 100% of MAESO enables improvements in the mechanical properties. Additionally, it is assessed whether the replacement of UP by MAESO is enough to improve the degradation properties, and the effect of degradation on the mechanical properties is analyzed. MAESO-St copolymers improve the degradation process in relation to UP, and 240 days of in vitro degradation in the presence of Aspergillus niger and Alternaria alternata fungi causes cracks, surface damage and changes in the mechanical properties of the degraded copolymer.
    Keywords: biobased polymers, soybean oil, degradation, unsaturated polyester resins, maleinization
  • Saba Raveshiyan, Parya Amirabedi, Reza Yegani *, Behzad Pourabbas, Akram Tavakoli Pages 61-71
    Wetting of polymeric hollow fiber membranes by chemical absorbents is one of the main challenges of gasliquid membrane contactors. This study explored an appropriate method to fabricate a superhydrophobic polypropylene (PP) hollow fiber membrane by incorporating fluorinated silica nanoparticles (fSiO2 NPs) on the PP membrane surface. The effect of the hydrophobic agent on the water repellent properties of the composite membrane was studied by varying (1H,1H,2H,2H-perfluorooctyltriethoxysilane/ tetraethylorthosilicate) (PFOTES/TEOS) molar ratio from 0 to 1. The composite membranes were characterized using field emission scanning electron microscopy (FESEM), attenuated total reflection-Fourier transform infrared (ATR-FTIR), contact angle, mechanical strength and static wettability. The obtained results showed that the surface hydrophobicity and mechanical strength of the composite membranes increased compared to pure ones. The contact angle of 156° was obtained when the (PFOTES/ TEOS) molar ratio was 0.5. Furthermore, the CO2 absorption experiment was done to evaluate the performance of the fabricated membranes in a gas-liquid membrane contactor. The obtained results showed that the PP/fSiO2 composite membrane has more potential to be used in gas-liquid membrane contactors than commonly used polymeric membranes
    Keywords: Superhydrophobic, Polypropylene membrane, Fluorinated silica nanoparticles, membrane contactor, wettability