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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Journal of Particle Science & Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: Mechanical properties,morphology,Polypropylene
- چکیده:
- چکیده انگلیسی: In this study, eight binary blends of polypropylene (PP)/ poly [styrene-b-(ethylene-co butylene)-b-styrene] tri-block copolymer (SEBS) and polypropylene (PP)/ polycarbonate (PC) were produced at different composition through twin screw extruder. The composition of the minor phases was changed to correlate the morphology and mechanical properties of binary blends (PP/PC and PP/SEBS) through thermal properties. To serve this purpose and to study the composition weight, composition weight ratio of SEBS and PC was change from 10% to 30% in PP/PC and PP/SEBS. With increasing SEBS wt%, toughness grows slightly and in 30wt% of SEBS reached to its maximum value, which uniform morphology created by PP/SEBS plays important role in this matter. On the other hand, with increasing PC wt%, tensile properties have upward trend, but size of holes, due to lack of proper adhesion between two polymeric surface, rose. The results of DCS have shown that SEBS cannot act as nucleation agents (heterogeneous nucleation) but the PC particles in this situation can act as nucleation agent in PP crystallinity. Increasing SEBS percentages leads to immobility of PP segments and hamper the crystallinity. PC particles in PP matrix are heterogeneous nucleation agent, which leads to increasing in crystallinity temperature compared to the pure PP.
- انتشار مقاله: 04-10-1395
- نویسندگان: Reza Veys Karami,Hossein Izadi Vasafi,Omid Moini Jazani,Alireza Talaei
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Particle Science & Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: Forward Osmosis (FO),Nanocomposite Substrates,Graphene Oxide nanoplates,Internal Concentration Polarization (ICP)
- چکیده:
- چکیده انگلیسی: One of the limiting factors in good performance of forward osmosis (FO) membranes is the internal concentration polarization (ICP). To reduce ICP, thin film nanocomposite forward osmosis (TFN-FO) membranes were fabricated by adding different amounts of graphene oxide (GO) nanoplates (0-1 wt. %) to polymer matrix of polysulfone (PSf) substrate. The prepared nanocomposite membranes exhibited both hydrophilicity and porosity higher than that of neat PSf counterpart. An optimum amount of 0.5 wt% was obtained for GO addition into the membranes. The corresponding fabricated thin film nanocomposite (TFN) membrane (TFNG0.5) revealed a water permeability of 2.44 L/m2hbar which is 66% higher compared to an in-house made composite membrane. The FO performance of TFN was assessed by DI water as feed solution and 1 M NaCl as draw solution in AL-DS orientation. The water flux of the synthesized FO membranes increased upon adding of GO nanoplates and reached to a maximum water flux of 37.74 (L/m2h) for TFNG0.5 membrane. This flux is about 3 times higher than TFC membranes without significant changes in their salt rejection. The higher water flux of the TFN membranes can be attributed to ICP decrease originating from reduction of structural parameter of the membranes.
- انتشار مقاله: 23-05-1395
- نویسندگان: Saharnaz Tajik,Omid Moini Jazani,Soheila Shokrollahzadeh,Seyed Mahdi Latifi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Particle Science & Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: Rheology,Bitumen,polymeric-modified bitumen,crumb rubber,poly (ethylene terephthalate)
- چکیده:
- چکیده انگلیسی: In this investigation, rheological properties of three different polymer-modified bitumen compounds containing recycled polyethylene terephthalate (R-PET), crumb rubber (CR) and poly (styrene-butadiene-styrene) (SBS) are evaluated and compared. The modified samples were tested by a dynamic shear rheometer (DSR) where complex modulus (G*), phase angle (δ) and rutting resistance (G*/Sinδ) of specimens were measured at different temperatures. The obtained results show that the optimum rheological properties will be gained when 7% wt. of a modifier mixture containing R-PET/CR (90/10 weight ratio) is added to the bitumen. In comparison with un-modified bitumen, the one modified by the latter modifier shows phase angle shift 68.9 oC, complex modulus 2190 (Pa) and rutting resistance 2520 (Pa), at temperature 80 oC. Generally, addition of the polymeric modifier increases complex modulus, rutting resistance and rigidity of the bitumen while a little decrease in phase angle is also observed.
- انتشار مقاله: 15-12-1394
- نویسندگان: Omid Moini Jazani,Marzieh Habibi Karahrodi,Ahmad Goli Khorasgani,Hossein Riazi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Particle Science & Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: High pressure,different pipes,Gas transportation,reinforced polyethylene,metal wire
- چکیده:
- چکیده انگلیسی: In this article various pipes used for transporting of gas are introduced and pros and cons of each one are elucidated. The pipes are categorized in three different subgroups including metallic, polymeric and metallic-wire reinforced polymeric pipes. Metallic-wire reinforced polymeric pipes are nominated as the best option for usage in high pressure pipelines transporting natural gas. As a result, some information about major manufacturers of this kind of polymeric pipes, raw material, production process and metallic-wire orientation are presented. Finally, from economical point of view, some calculations are done to estimate required amount of polymer and metallic-wire to manufacture such pipes. It is also possible to compare their manufacturing cost with usual metallic and polymeric pipes.
- انتشار مقاله: 08-01-1394
- نویسندگان: Omid Moini Jazani,Reyhaneh Khalafi,Mohammad Khosravi,Mohammad Reza Hassanpour,Danial Dadkhah,Mehdi Mostafaeian,Mohammad Mahdi Salehi,Hossein Riazi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Particle Science & Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: Reaction time,Anionic Polymerization,ε-Caprolactam,Polyamide 6
- چکیده:
- چکیده انگلیسی: The main objective of the present work was to synthesis polyamide 6 through anionic polymerization of ε-caprolactam in an internal mixer. The reaction time and the rheological properties of samples during the polymerization were studied. The samples were characterized by Thermo Gravimetry Analysis (TGA), Differential Scanning Calorimeter (DSC) and FT-IR spectrometer. The melt flow behavior and viscoelastic properties of the samples were studied by using a Rheometric Mechanical Spectrometer (RMS). The polymerization reaction was found to be very fast such that it completed within 6 minutes as could be detected by following the mixing torque which reached to a steady state after passing a maximum. These results suggest that there is a reaction time above which the viscoelastic behavior of the samples almost remained unchanged, while the viscosity and elasticity of the samples continue to decrease with polymerization reaction time as a result of thermochemical degradation.
- انتشار مقاله: 21-10-1393
- نویسندگان: Mohammad Mahdi Salehi,Omid Moini
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Particle Science & Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: Mechanical properties,morphology,Ternary Blend,PP/PET/SEBS
- چکیده:
- چکیده انگلیسی: In this work, ternary polymer blends based on polypropylene (PP)/ polyethylene terephthalate (PET) /poly(styrene-b (ethylene-co-butylene)-b-styrene) (SEBS) triblock copolymer and a reactive maleic anhydride grafted SEBS (SEBS-g-MAH) at various compositions were prepared by co-rotating twin screw extruder. The effects of PET, SEBS and SEBS-g-MAH compatibilizer on morphology of the blends were examined by scanning electron microscopy (SEM). The blends morphology was also estimated by some predicting methods, however, SEM results revealed some contrasts between results of predicting methods and the real morphology. Population of individual and core-shell particles as well as average diameter of the rubber-based cavities is extremely dependent on SEBS, SEBS-g-MA and PET content. Mechanical inspection tests showed that in comparison with the pure PP, addition of SEBS/SEBS-MA causes an increase in the impact strength of the system. Keeping other parameters constant, with increase in SEBS rubbery phase, the core-shell morphology was affected and the impact strength increased consequently. On the other hand, increase in PET content results in modulus increase and the impact strength decrease. Finally, the optimum processing conditions for compounding ternary PP/PET/SEBS blends were achieved.
- انتشار مقاله: 29-08-1393
- نویسندگان: Omid Moini Jazani,Mohammad Ali Khoramabadi,Mohammad Mahdi Salehi,Hossein Riazi,Fariba Soltanokottabi
- مشاهده