Behzad Shirkavand Hadavand | Institute for Color Science and Technology (original) (raw)

Papers by Behzad Shirkavand Hadavand

Fullerenes, nanotubes, and carbon nanostructures/Fullerenes, nanotubes and carbon nanostructures, Feb 6, 2024

Environmental Pollution, Sep 1, 2023

Polymer-plastics technology and materials, Jun 22, 2022

In this study, we are going to produce UV-curable hydrogel hybrids with carbon quantum dots. For ... more In this study, we are going to produce UV-curable hydrogel hybrids with carbon quantum dots. For this purpose, after synthesizing CQDs, they were reacted with acrylic acid to establish covalent bonds and create a C = C bond on the surface of CQDs. Then acrylamide hydrogel was synthesized. In the next step, 1, 3 and 5% UV-curable hydrogel hybrids were prepared. The experimental results displayed that increasing the amount of CQDs in the hydrogel increased photoluminescence intensity and water adsorption while boosting the hydrogel's thermal stability. Besides, increasing the CQDs amount reduces the hydrogel elasticity.

Materials in engineering, Sep 1, 2013

In this research, multi-walled carbon nanotubes (MWCNTs) were modified by acid functionalization ... more In this research, multi-walled carbon nanotubes (MWCNTs) were modified by acid functionalization (H 2-SO 4 :HNO 3 = 1:3 by volume) and then mechanical properties of reinforced epoxy polysulfide resin by the both pure and treated MWNTs have been evaluated. For achieving this goal, different weight percentages of pure and treated MWCNT (0.1-0.3 wt%) were dispersed in the epoxy polysulfide resin separately and then mixed with curing agent. Experimental results have shown significant difference between acid treated and untreated MWCNTs in mechanical properties of epoxy polysulfide nanocomposites. In nanocomposite with 0.1-0.3% acid treated MWCNTs we observed increase of Young's modulus from 458 to 723 MPa, tensile strength from 5.29 to 8.83 MPa and fracture strain from 0.16% to 0.25%. For understanding the structure and morphology of nanocomposite, the dispersion states were studied using scanning electron microscopy (SEM) and field emission electron microscopy (FESEM). The results showed better dispersion of modified carbon nanotube than unmodified in polymeric matrix.

Journal of Inorganic and Organometallic Polymers and Materials, Apr 6, 2023

Applied Physics A, 2012

Silver nanoparticles with size less than 50 nm were synthesized from silver nitrate, polyvinylpyr... more Silver nanoparticles with size less than 50 nm were synthesized from silver nitrate, polyvinylpyrrolidone (PVP) and ethylene glycol, where these chemicals acted as metal precursor, stabilizer and reducing agent, respectively. Then a conductive silver ink was prepared with a suitable solvent by adding a viscosifier, hydroxyethyl-cellulose (HEC), and a surfactant, diethylene glycol (DEG). The combined effect of both viscosifier and surfactant on the physical property of the silver ink was analyzed by measuring the contact angle of the silver ink on a cellulose film. Moreover, the influences of PVP molecular weight and reaction temperature on the size of the silver nanoparticles were analyzed. Then the silver ink was coated on the cellulose film by spin coating and the effects of different solvents, sintering temperatures and solid contents on its electrical resistivity were examined. It was found that, with 50 % co-solvent of deionized water and DEG and solid content of around 50 %, the silver ink exhibited the lowest resistivity. This ink can be used for inkjet printing of conductive patterns on cellulose films.

Journal of Composite Materials, Jun 29, 2019

Attention to environmental problems and the importance of maintaining it have caused the research... more Attention to environmental problems and the importance of maintaining it have caused the researchers to pay more attention in this regard. The production of polymers and resins has increased in recent years and has affected by environmental pollution due to their long-term degradation. An appropriate solution to this problem is the synthesis of degradable and environmentally friendly polymers and resins. Using natural materials in the synthesis of polymers and resins can help them to be environmentally friendly. The purpose of this research is to synthesize urethane acrylate resins using natural resources. For this purpose, the urethane acrylate pre-polymer was synthesized with castor oil. Then, using modified zinc oxide nanoparticles with 1, 3 and 5 wt% urethane acrylate zinc oxide nanocomposites were produced. The use of castor oil as a degradable part and lack of organic solvent in radiation systems led to the creation of an environmentally friendly resin. Subsequently, the viscoelastic behavior of the prepared nanocomposite was evaluated. Spectrometry results confirm the synthesized resin structure. The morphology of nanocomposites confirmed the proper particle size distribution in a 3 wt.% sample. The results of the dynamic mechanical thermal analysis test showed that increasing the amount of modified nano ZnO could increase the glass transition temperature, and the maximum value was observed in 5 wt.% modified nano ZnO (69.7 C).

Fullerenes Nanotubes and Carbon Nanostructures, Jun 22, 2023

Polymer-Plastics Technology and Materials

ABSTRACT This study aims to investigate the reinforcing effects of graphene quantum dots on vario... more ABSTRACT This study aims to investigate the reinforcing effects of graphene quantum dots on various properties of epoxy resins. To do this, graphene quantum dots were synthesized, then, characterized by various spectroscopic methods. These nanoparticles including several weight percentages along with a curing agent were added to epoxy resin. Finally, fluorescent epoxy graphene quantum dots nanocomposites were prepared. FTIR, photoluminescence, UV-visible absorption, FESEM, TGA, tensile testing and DMTA analysis were used to characterize the resultant nanocomposites. Findings evinced that adding graphene quantum dots to the epoxy resin led to an improvement of thermal stability, mechanical features, and viscoelastic properties of nanocomposites. Graphical abstract

Flame Retardancy and Thermal Stability of Materials, 2019

Disposal of plastics in the form of discarded scrap or waste is an environmental nightmare to the... more Disposal of plastics in the form of discarded scrap or waste is an environmental nightmare to the developed and under-developing countries. In this sense, modern technologies are every day growing; meanwhile recycling wastes are taking credit for higher performance to pave the way towards a cleaner planet. Recycling of polymer blends is associated with serious complexities in finding appropriate additives acting in each phase or at the interface of non-miscible polymers to attain materials with higher properties. A flame retardant system was designed and intended to play the role of typical recycled flame retardant polypropylene/polyamide (PP/PA6) blends by incorporation of two kinds of talc, sepiolite, and a phosphorus-based flame retardant. First, two types of talcs having different physical properties were added to PA6 in combination with melamine cyanurate (MC) or melamine pyrophosphate (MPP) to find the one acting as a barrier during combustion. Then, high-aspect-ratio talc tha...

Case Studies in Thermal Engineering

Pigment & Resin Technology, Aug 3, 2022

Journal of Composite Materials

This research focuses on synthesis and study of the properties of castor oil-based epoxy/carbon q... more This research focuses on synthesis and study of the properties of castor oil-based epoxy/carbon quantum dots (COEp/CQDs) nanocomposite coatings possessing resistance against UV. First, CQDs were synthesized by pyrolysis of starch using microwave-assisted method and characterized via various spectroscopic and microscopic methods. Next, certain quantity of castor oil as a renewable resource, CQDs with different weight percentages and a curing agent were added to epoxy resin and consequently COEp/CQDs were prepared. Through findings of FTIR, photoluminescence and UV-visible spectroscopy analyses, existent functional groups and fluorescent feature of the nanocomposite coatings were confirmed. UV-vis spectroscopy approved UV resistance of the COEp/CQDs coatings. As concentration of CQDs increased in resin matrix, UV absorption was maximized. The morphology and uniform dispersion of CQDs in the coatings matrix were verified by FESEM analysis. Results of TGA, pull-off adhesion strength and...

Journal of Applied Chemical Research, Oct 1, 2021

Main Group Chemistry

Nowadays, different structures of organic macrocyclic compounds are considered because of their a... more Nowadays, different structures of organic macrocyclic compounds are considered because of their attractive applications. One of the main problems in the synthesis of these materials is their long reaction time but low reaction yield. The use of catalysts can be effective in solving this problem. Among the catalysts, nano-copper chromite can be a good choice due to its good performance in the synthesis of organic compounds. In addition, the Response Surface Methodology was used to investigate the effective parameters in the synthesis more precisely. Based on the previous results of the synthesis and experiments, the catalyst content from 0% to 5% to raw material and reaction time between 24 and 96 h was chosen for the design of the experiment. After determining the reaction yield results, a suitable model was selected and its accuracy was evaluated. Results showed for yields above 95% with minimum catalyst (2.29%) the reaction time of 88 h and for minimum time (65 h), 3.85% of the ca...

Steel and Composite Structures, 2020

Multi-Walled Carbon nanotubes (MWCNT) coupled with Silicone Rubber (SR) can represent applicable ... more Multi-Walled Carbon nanotubes (MWCNT) coupled with Silicone Rubber (SR) can represent applicable strain sensors with accessible materials, which result in good stretchability and great sensitivity. Employing these materials and given the fact that the combination of these two has been addressed in few studies, this study is trying to represent a low-cost, durable and stretchable strain sensor that can perform excellently in a high number of repeated cycles. Great stability was observed during the cyclic test after 2000 cycles. Ultrahigh sensitivity (GF>1227) along with good extensibility (e>120%) was observed while testing the sensor at different strain rates and the various number of cycles. Further investigation is dedicated to sensor performance in the detection of human body movements. Not only the sensor performance in detecting the small strains like the vibrations on the throat was tested, but also the larger strains as observed in extension/bending of the muscle joints...

Journal Of Macromolecular Science, Part A, Mar 30, 2022

In this research, the synthesis, characterization and thermal stability of UV curable hydrogels h... more In this research, the synthesis, characterization and thermal stability of UV curable hydrogels have been investigated. To this end, urethane acrylate was initially synthesized with isophorone diisocyanate, polyethylene glycol and hydroxyethyl methacrylate. In the next step, the UV curable hydrogel was synthesized with acrylamide, acrylic acid and the urethane acrylate. FTIR spectra proved the structure of urethane acrylate and hydrogel. The study of thermal behavior showed that the synthesized hydrogel is stable to 327 ℃.

Nanomaterials Application Properties 2013, Jul 21, 2013

This study related to preparation of UV curable epoxy nanoclay nanocomposite and investigation on... more This study related to preparation of UV curable epoxy nanoclay nanocomposite and investigation on mechanical and thermal properties of their thin films. For achieving this UV-curable epoxy dimethacrylate was synthesized by epoxy resin (EPIKOTE 828), methacrylic acid, triphenylphosphine (PPh3) as catalyst and para-methoxy phenol (PMP) as inhibitor at 80 ºC for 2 hours (yield 99%). Formulation of UV curable resin was achieved by 5% w/w benzophenone and N, N dimethylaminoethyl methacrylate. The resin was reinforced by using 1-5% w/w modified nanoclay in total formulation. Synthesized resin was characterized by FTIR spectroscopy and thermal behaviors of nanocomposites were evaluated by TGA and DSC analysis.