Enis S. Džunuzović's research while affiliated with Faculty of Technology and Metallurgy, University of Belgrade and other places

Publications (50)

Conference Paper
Full-text available
In this study, six waterborne polyurethanes (WBPUs) were synthesized based on α,ω-dihydroxypropyl poly(dimethylsiloxane) (PDMS), isophorone diisocyanate (IPDI), 2,2-bis-(hydroxymethyl) propionic acid (DMPA) and triethylamine (TEA). WBPUs were prepared without a chain extension step and with various DMPA/PDMS molar ratios (from 0.2 to 0.7). The mech...
Conference Paper
Full-text available
A series of novel waterborne polyurethanes (WBPUs) was synthesized using α,ωdihydroxypropyl poly(dimethylsiloxane) (PDMS), isophorone diisocyanate (IPDI), 2,2-bis-(hydroxymethyl) propionic acid (DMPA) and triethylamine (TEA). Different DMPA/PDMS and constant –NCO/–OH molar ratio have been applied for the synthesis of six different WBPUs, without th...
Conference Paper
Full-text available
Waterborne polyurethanes (WBPUs) represent a class of polyurethanes (PUs), in which water is used as the dispersion medium, instead hazardous organic solvents. In this manner, the emission of volatile organic compounds is decreased, leading to the environmental preservation. Poly(dimethylsiloxane) (PDMS) has a lot of useful features, such as low gl...
Article
Full-text available
The scope of the present study was to prepare fully bio-based unsaturated polyester resins (UPRs) with comparable properties to the commercial formulations. The focus was set on the determination of the optimal prepolymer formulation using the same set of diacids (itaconic and succinic acid) and different diols (propylene glycol, isosorbide and neo...
Article
Full-text available
This work was focused on the synthesis of polyurethane networks (PUNs) based on polycaprolactone (PCL) as soft segment (SS) and Boltorn® aliphatic hyperbranched polyester of the second pseudo generation and 4,4′-diphenylmethane diisocyanate (MDI) as the parts of the hard segments (HS), by a two-step solution polymerization. In order to find the bes...
Article
A series of novel waterborne polyurethanes (WBPUs) was synthesized using α,ω-dihydroxypropyl poly(dimethylsiloxane) (PDMS), isophorone diisocyanate (IPDI), 2,2-bis-(hydroxymethyl) propionic acid (DMPA) and triethylamine (TEA). Different DMPA/PDMS molar ratio (from 0.2 to 0.7) and fixed –NCO/–OH molar ratio of 1.7, has been applied for the synthesis...
Article
A series of environmentally friendly polyurethane (PU) networks based on polycaprolactone as soft segment (SS) and Boltorn® aliphatic hyperbranched polyester of the second pseudo generation as crosslinking agent was prepared by a two-step polymerization in solution. The chemical structure of the PU networks was analyzed by Fourier transform infrare...
Article
Poly(o-toluidine) (POT) is electrochemically synthesized on graphite electrode at constant current density of 1.5 mA cm −2 from aqueous electrolyte of 1.0 mol dm −3 H 2 SO 4 and 0.25 mol dm −3 o-toluidine. Electrochemical characterization of POT electrode is performed using cyclic voltammetry, Mot Schottky analysis and galvano-static measurements a...
Article
The visible-light-responsive inorganic-organic hybrid was prepared by surface modification of commercial TiO 2 powder (Degussa P25) with 4-chlorophenol (4-CP). The optical absorption of the hybrid material is red-shifted compared to unmodified TiO 2 powder due to the surface charge transfer complex (CTC) formation. The experimental results are supp...
Article
Size‐dependent antimicrobial ability of silver nanoparticles (Ag NPs) supported by amino‐functionalized poly(glycidyl methacrylate‐co‐ethylene glycol dimethacrylate) (poly(GMA‐co‐EGDMA)) macroporous copolymer was tested against Gram‐negative bacteria Escherichia coli. Inorganic/organic hybrids with distinctly different average sizes of Ag NPs (6.6...
Conference Paper
Full-text available
Polyurethane networks (PUN) represent versatile materials which are usually consisted of different hard (HS) and soft segments (SS). They possess very good mechanical, thermal and surface properties. Such properties originate from their different composition, chemical structure of the crosslinking agent and molecular weights of the HS and SS. In th...
Article
Full-text available
Surface modification of titanium dioxide nanoparticles (TiO2 NPs) with the biologically active molecule pyridoxine hydrochloride (vitamin B6) was found to alter the optical properties. Microstructural characterization involving transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis revealed that the anatase TiO2 NPs had a narro...
Article
The charge transfer complex formation between TiO2 powder and variety of phenol derivatives (phenol, 4-nitrophenol, 4-bromophenol, 4-tert-butylphenol, hydroquinone) was achieved. The red-shift of optical absorption was observed upon surface modification of TiO2 powders with phenol derivatives. The influence of substituent functional groups in para...
Article
Poly(aniline-co-(m-aminobenzoic acid)) was synthesized electrochemically at graphite electrode under galvanostatic conditions. Aqueous electrolyte for synthesis was consisted of HCl and different amount of aniline and m-aminobenzoic acid. The presence of the meta positioned carboxylic group in m-aminobenzoic acid influenced higher co-polymerization...
Article
Full-text available
Influence of hematite nanorods on the mechanical properties of epoxy resin Bogdanović Gordana, Kovač Tijana S., Džunuzović Enis S., Špírková Milena, Ahrenkiel Phillip S., Nedeljković Jovan M. Mechanical properties of nanocomposites, obtained by incorporation of fairly uniform hematite nanorods (α-Fe2O3 NRs) into epoxy resin, were stu-died as a fu...
Article
Novel TiO2-PANI core-shell nanocomposite, prepared by in situ oxidative polymerization of aniline in thepresence of TiO2nanoparticles surface modified with vitamin B6, was used to reinforce epoxy resin. Thesize of prepared TiO2nanoparticles and TiO2-PANI nanocomposite were determined by a transmissionelectron microscopy (TEM). The surface modificat...
Article
The synthetic procedures for preparation of free-standing and attached to polymer support surface-modified TiO2 nanoparticles (NPs) with absorption extended into visible spectral region due to charge transfer complex formation were developed. The one-step synthesis of colloids consisting of surface-modified TiO2 NPs is based on the reaction between...
Article
Alkyd resin/TiO2 nanocomposites (NC) were prepared from short oil alkyd resin and TiO2 nanoparticles (NPs) surface modified with in situ formed imine ligand, based on 3,4-dihydroxybenzaldehyde and oleylamine, or with three gallic acid esters. The short oil alkyd resin was synthesized from sunflower oil, phthalic anhydride, and trimethylolpropane. U...
Article
The use of penicillin G acylase (PGA) covalently linked to insoluble carrier is expected to produce major advances in pharmaceutical processing industry and the enzyme stability enhancement is still a significant challenge. The objective of this study was to improve catalytic performances of the covalently immobilized PGA on an potential industrial...
Article
Unsaturated polyester resin (UPe)-based nanocomposites and fumed silica Aerosil R812S, R805 and R816, and R200 modified with phenyl terminal group, R200NPh, were prepared. UPe resins were synthesized from maleic anhydride and products of glycolysis, obtained by polyethylene terephthalate depolymerization with dipropylene glycol in the presence of t...
Article
The poor stability and tendency to agglomerate of unfunctionalized nano-SiO2 in the presence of ionic species presents a challenge for preparing poly(methacrylic acid)/nano-SiO2 nanocomposite (NC) hydrogels with desired strength and swelling capability. We proposed a facile and eco-friendly method for the preparation of PMAA/SiO2 NC hydrogels using...
Article
Full-text available
TiO 2 nanoparticles, obtained by acid catalyzed hydrolysis of titanium isopropox-ide, were surface modified by three gallic acid esters with different hydrophobic part length: octyl, decyl and lauryl gallate, and then used to prepare TiO 2 /epoxy nanocomposites. The characterization of the surface modified TiO 2 nanoparti-cles was performed by FTIR...
Article
Epoxy resin/titanium dioxide (epoxy/TiO2) nanocomposites were obtained by incorporation of TiO2 nanoparticles surface modified with gallic acid esters in epoxy resin. TiO2 nanoparticles were obtained by acid catalyzed hydrolysis of titanium isopropoxide and their structural characterization was performed by X-ray diffraction and transmission electr...
Article
Full-text available
Composite consisting of silver nanoparticles coordinated to poly(GMA-co-EGDMA) macroporous copolymer was prepared by attachment of amino group to the poly(GMA-co-EGDMA) in the reaction with ethylene diamine, and consequent reduction of silver ions with amino groups at elevated temperature. The infrared measurements indicated that surface of silver...
Chapter
Polystyrene, one of the most important material in the modern plastic industry and one of the major synthetic polymer in use today, offers an extremely broad range of applications, due to its good physical properties and low-cost. Significant change of mechanical, rheological, thermal, optical, fire retardancy and barrier properties of polystyrene...
Article
Full-text available
Composites based on unsaturated polyester (UPe) resins and fumed silica AEROSIL (R) RY 50, NY 50, RX 50 and NAX 50, as well as graphite, TiO2 or organically modified clay CLOISITE 30B were prepared in order to investigate the influence of reinforcing agents on the mechanical properties of composites. Unsaturated polyester resins were synthesized fr...
Article
Full-text available
Spherical TiO2 particles of different size were dispersed in alkyd resin based on soybean oil. Four samples of TiO2 particles were used, three commercial and one obtained by acid catalyzed hydrolysis of titanium tetraisopropoxide. The size of the synthesized nanoparticles was determined by transmission electron microscopy. Surface modification of T...
Article
Incorporation of surface modified TiO2 nanoparticles into polystyrene (PS) matrix was achieved by in situ bulk radical polymerization of styrene. The surface of TiO2 nanoparticles was modified with four amphiphilic esters of the gallic acid (octyl, decyl, lauryl and cetyl gallate), which have different lengths of hydrophobic alkyl chain (C8–C16). F...
Chapter
Hyperbranched polymers represent intriguing class of dendritic polymers, which show remarkable, unique and different chemical and physical properties compared to their linear counterparts, as a result of their complex, three-dimensional structure, presence of a large number of end functional groups and low degree of entanglement. Partial or complet...
Article
The properties of urethane acrylate resin mixtures based on the linear and hyperbranched aliphatic polyesters were examined. Linear polyester was synthesized from neopentil glycol and adipic acid. Hyperbranched polyester of the third generation was synthesized from 2,2-bis(hydroxymethyl)propionic acid and di-trimethylol propane. The modification of...
Article
Full-text available
Incorporation of inorganic nanoparticles can significantly affect the properties of the polymer matrix. The properties of polymer nanocomposites depend on the type of incorporated nanoparticles, their size and shape, their concentration, and interactions with the polymer matrix. Homogeneity of polymer nanocomposites is influenced very much by the p...
Article
Full-text available
Surface modified silver nanoparticles dispersed in chloroform were encapsulated in poly(methylmethacrylate) (PMMA) by in-situ radical polymerization of methyl methacrylate initiated by 2,2′-azobisisobutyronitrile. The particle size distribution of colloidal silver nanoparticles was determined using transmission electron microscopy. The obtained tra...
Article
Full-text available
Surface modification of nanocrystalline TiO(2) particles (45 A) with bidentate benzene derivatives (catechol, pyrogallol, and gallic acid) was found to alter optical properties of nanoparticles. The formation of the inner-sphere charge-transfer complexes results in a red shift of the semiconductor absorption compared to unmodified nanocrystallites....
Article
The surface of anatase TiO2 nanoparticles, obtained by the controlled hydrolysis of titanium tetrachloride, was modified by 6-palmitate ascorbic acid. The surface modified TiO2 nanoparticles were dispersed in methyl methacrylate and mixed with a appropriate amount of poly(methyl methacrylate) to obtain a syrup. The nanocomposite sheets were made by...
Article
TiO2 nanoparticles, surface modified with 6-palmitate ascorbic acid, were incorporated in polystyrene (PS) by in situ bulk radical polymerization of styrene using 2,2′-azobisisobutyronitrile as initiator. The molar mass and polydispersity of synthesized samples were estimated by gel permeation chromatography. The influence of surface modified TiO2...
Article
Poly(methyl methacrylate)/α-Fe2O3 composites were prepared by in situ bulk radical polymerization of methyl methacrylate in the presence of the cubic α-Fe2O3 particles using 2,2′-azobisisobutyronitrile as initiator. The cubic α-Fe2O3 particles were synthesized by forced hydrolysis of FeCl3 and characterized by X-ray diffraction analysis and transmi...
Article
The synthesis and characterization of poly(itaconic acid) (PIA) with a novel initiator/activator system is presented. The initiator in this system was potassium persulfate, whereas the activator was N,N-dimethylethanolamine (DMEA). PIA was synthesized in distilled water and in 0.1M HCl at 40°C with reaction times of 72 and 96 h. PIA was investigate...
Article
α-Fe2O3 nanorods were incorporated into poly(methyl methacrylate) (PMMA) by in situ radical polymerisation of methyl methacrylate initiated by 2,2′-azobisisobutyronitrile. The α-Fe2O3 nanorods were synthesized by forced hydrolysis of FeCl3 and structural characterization was performed by X-ray diffraction and transmission electron microscopy. The m...
Article
Surface modified TiO2 nanoparticles dissolved in toluene were encapsulated in PMMA by in situ radical polymerization of methyl methacrylate initiated by 2,2′-azobisisobutyronitrile. The surface modification of the TiO2 nanoparticles (average diameter of 4.5 nm) was achieved by the formation of a charge transfer complex between TiO2 nanoparticles an...
Article
Urethane acrylate resins based on partially modified aliphatic hyperbranched polyesters (HBP) were synthesized. HBP of the second and the third pseudo-generation were synthesized from 2,2-bis(hydroxymethyl)propionic acid and di-trimethylol propane. The modification of 60% of the OH end-groups was carried out with isononanoic acid. Urethane acrylate...
Article
Urethane acrylate resins based on partially modified aliphatic hyperbranched polyesters (HBP) have been synthesized. HBP of the second and the third generation were synthesized from 2,2-bis(hydroxymethyl)propionic acid and di-trimethylol propane. The modification of certain amount of OH end-groups was carried out with soybean fatty acids. The ureth...
Article
Intermolecular complex formation through hydrogen bonding between poly(itaconic acid), partially neutralized and non-neutralized, and polyacrylamide was studied by potentiometry. The complexes were obtained by template polymerization of itaconic acid and partially neutralized itaconic acid on polyacrylamide as a template. All the complexes were cha...
Article
Intermolecular complex formation through hydrogen bonding between poly(itaconic acid), partially neutralized and non-neutralized, and polyacrylamide was studied by potentiometry. The complexes were obtained by template polymerization of itaconic acid and partially neutralized itaconic acid on polyacrylamide as a template. All the complexes,were cha...
Article
Semi-IPNs based on polyacrylamide (PAAm) and poly(itaconic acid) (PIA) were prepared by two different techniques, polymerizing itaconic acid in the presence of polyacrylamide gel (Samples I) and by makiug the polyacrylamide gel in the presence of poly(itaconic acid) (Samples 11), with different PAAm/PIA ratios. The swelling behavior of the semi-IPN...

Citations

... This ATH reacts at a temperature of 180-200 • C into aluminum oxide through an endothermic reaction, which causes the UPRs to cool down, thereby reducing the pyrolysis product [39,51]. The cross-linking of UPRs also keeps the polymer chains from breaking under the influence of heat [52,53]. when burned. ...
... Good hydrophobicity originates from PDMS which has known to possess low surface energy and have a high tendency to migrate on the surface of the WBPUs. The synthesis of these WBPUs represents a more efficient and eco-friendly way for preparation of polyurethanes and they are good candidates for application as coatings (1). ...
... As with the DSC, the XRD method showed that the initial PUU films with long PCL segments formed on a glass substrate have the structure of a semi-crystalline polymer, regardless of the structure of the hard aromatic blocks. Their XRD patterns in the region 2θ = 15-30 • show sharp peaks at Bragg angles of 21.4 • and 23.7 • , which are attributed to the crystal planes of (110) and (200) and indicate the existence of the orthorhombic crystal lattice of semi-crystalline PCL in PUU [48,49]. In the case of the same compositions of multiblock copolymers based on PCL with M n = 0.53 × 10 3 , only a wide amorphous halo was observed in this angle range since the length of the soft aliphatic segments with sufficiently massive aromatic blocks is insufficient for self-ordering (Figure 9). ...
... Mishra has verified that introducing hyperbranched polyether polyols could effectively enhance the hydrophobicity and mechanical properties effectively [17]. Unfortunately, they could not endow coatings with higher antifouling properties for their insignificant antifouling ability [18]. Since Frey developed the hyperbranched polyglycerol (HPG), presenting a similar hyperbranched structure to those hyperbranched polyester polyols, which was linked with ether bonds and capped with abundant hydroxyl groups, the extraordinary antifouling property of HPG has been reported [19]. ...
... Intrinsically conducting polymers (ICP) are considered as perspective energy storage materials [1][2][3][4][5][6][7][8]. They can be synthesized by both chemical and electrochemical procedures; they are stable, inexpensive, ecologically acceptable, light-weighted, and have reversible electrochemistry. ...
... They are intrinsic, basic, and relatively stable psychological qualities and characteristics. These psychological attributes and physiological characteristics determine whether to affect the individual's psychological, physiological, and social functions and then affect the individual's mental health [24]. Therefore, the quality of mental health is an important aspect of mental health that affects a person's level of mental health. ...
... Meanwhile, the inorganic particles nucleate PET through the so-called "particle effect," which avoids the chemical degradation of PET by the organic nucleating agents [18]. On the other hands, silver nanoparticles (Ag NPs) have been widely used in various fields due to their diverse optical, electric, catalytic and anti-microbial properties [19][20][21][22][23][24][25][26], which implies that the novel polyesters with tunable crystallization rate and multifunctional properties could be obtained if Ag NPs can be incorporated with polyesters materials. For instance, Ag NPs were covalently immobilized with poly L-lactic acid (PLLA) to construct fibrous mat or membranes with good anti-bacterial properties [27,28]. ...
... 49 PAN was widely used in various resins, such as epoxy, alkyd, acrylic, and efficiency. [49][50][51] When doping with camphor sulphonate, phenyl phosphonate and iodine, the doped PAN gives a double protection effect. 49,58 At rst, the redox reaction that occurs between Fe and PAN leads to the reduction of PAN and the release of the doped anion. ...
... Until now, the surface of TiO 2 has been coordinated mainly with benzene derivatives with either two adjacent hydroxyl groups (catecholate-type of ligands) or with adjacent hydroxyl and carboxyl group (salicylate-type of ligands) [15][16][17][18][19][20][21][22][23][24][25][26]. Very recently, the CTC formation between TiO 2 and organic mono-hydroxy compounds, such as phenol derivatives and vitamin B6, was reported in the literature [27][28][29]. It should be emphasized that photogeneration of charge carriers takes place in the single step, i.e. electrons are directly injected from the ground state of the CTC, located in the semiconductor band gap, into the semiconductor conduction band. ...
... (Scheme B1). Later, galvanostatic polymerization was also carried out which gave the same result with polyaniline e.g., Milica M. Gvozdenović et al. [52] demonstrated the electrochemical synthesis of poly (aniline-co-(mamino-benzoic acid) from monomer aniline (ANI) and m-amino-benzoic acid (PAMBA) through controlled ANI/PAMBA stoichiometric ratio (3:1 & 2:1). They observed galvanostatic curves of poly (aniline-co-(mamino-benzoic acid) film at a scan rate of 1 mA cm and constant current density set of 1.0 mA/cm 2 using solvent/electrolytic pair system such as H 2 O/(1 M HCl) deposited on a graphite electrode. ...