Sanja lučić blagojević

• Professor (Full) at University of Zagreb

In this research, the influence of titanium dioxide (TiO2) nanoparticles and their modifications on the weathering resistance of untreated and heat-treated wood was studied. The wood samples were coated with polyacrylate waterborne emulsion coatings that contain nano-TiO2 in the amount of 0.75 wt.%. Two types of modifiers were used to modify the na...

Adhesion of the most common dental biofilm bacteria to alloys used in orthodontics in relation to surface characteristics was analyzed. Streptococcus mutans (S. mutans), Streptococcus oralis (S. oralis), Veillonella parvula (V. parvula), and Aggregatibacter actinomycetemcomitans (A. actynomicetemcomitans) were incubated for 4 h with nickel-titanium...

The aim of this work is to prepare polyacrylate emulsions (PA) with the addition of modified titanium dioxide (TiO2) nanoparticles. The modifiers used in this work are the nonionic emulsifier TX-100, the cationic initiator AIBA, the silane AMPTS, and the trisilanol POSS. The results show that particles with a larger hydrodynamic diameter are formed...

Klebsiella pneumoniae is an emerging multidrug-resistant pathogen that can contaminate hospital surfaces in the form of a biofilm which is hard to remove with standard disinfectants. Because of biofilm resistance to conservative disinfectants, the application of new disinfection technologies is becoming more frequent. Ozone gas has antimicrobial ac...

Bacterial contamination of the membranes used during guided bone regeneration directly influences the outcome of this procedure. In this study, we analyzed the early stages of bacterial adhesion on two commercial dense polytetrafluoroethylene (d-PTFE) membranes in order to identify microstructural features that led to different adhesion strengths....

This work aims to prepare a coating with good UV protection properties while maintaining optimal transparency. In this work, the addition of 0–2 wt.% TiO2 on the properties of polyacrylate (PA), the method of preparation, and the effect of UV exposure on coatings were investigated. Rutile TiO2/PA coatings were prepared by ex situ and in situ emulsi...

The development of coatings that maintain the attractive natural appearance of wood while providing ultraviolet (UV) protection is extremely important for the widespread use of wood products. In this study, the influence of different types (powder form and aqueous dispersions) of TiO2 in an amount of 1.0 wt% by monomer weight on the properties of e...

Purpose The purpose of this paper is to prepare stabile emulsions with 0–15% of colloidal silica and high monomer/water ratio and to investigate the influence of silica addition and surface modification on the polyacrylate properties. Design/methodology/approach Improving the properties of the composite can be achieved by optimizing the compatibil...

Pure and doped vanadia (VO2, V0.98Zr0.02O2, V0.98Ce0.02O2) samples were prepared by wet chemistry synthesis from vanadyl glycolate intermediate phase and tape casted into films. Combining in-operando grazing incidence synchrotron X-ray diffraction and Raman spectroscopy, we studied the structural evolution of the films under isothermal conditions....

Selektivno lasersko sinteriranje (SLS) jedan je od važnijih postupaka 3D ispisa koji se u današnje vrijeme sve više primjenjuju za dobivanje različitih modela. Najvažniji polimerni materijali koji se upotrebljavaju u tom procesu su poliamidi. Značajan nedostatak tog procesa je velika količina otpadnog polimernog praha. Stoga je cilj ovoga rada bio...

In this study, the addition of carbon nanotubes (MWCNT) and modified carbon nanotubes (MWCNT-COOH) in the range of 0.5 wt. % to 5 wt. % in polyamide (PA) obtained as a residue upon 3D printing, was investigated. PA and nanocomposite samples were prepared by melt mixing. PA/MWCNT and PA/MWCNT-COOH nanocomposites were characterized by differential sc...

U ovom radu istra?ivan je u?inak dodatka vi?estjenih ugljikovih nanocjev?ica (MWCNT) te MWCNT-a modificiranog skupinama COOH (MWCNT-COOH) u rasponu masenih udjela od 0?do?4?% na svojstva termoplasti?nog poliuretana (PU). Uzorci nanokompozita pripravljani su postupkom polaganog su?enja iz smjese poliuretana i nanopunila u acetonu pri sobnoj temperat...

In this study influence of monomer ratio, butyl acrylate (BA), and methyl methacrylate (MMA) as well as silica nanofiller morphology (pyrogenic and colloidal) and concentration on the emulsion particle size distribution and properties of polyacrylate film (PA) synthesized by in situ emulsion polymerization were investigated. The ratios of the monom...

In this article, isothermal crystallization kinetic of the linear hydroxyl polyester urethane (PUR), as well as influence of amorphous silica nanofiller, was investigated. With the aim to investigate the influence of filler surface modification on the crystallization process of polyurethane matrix, nonmodified silica, as well as silica modified wit...

Mechanical and morphological properties of composites containing styrene—acrylonitrile (SAN) copolymer, ethylene— propylene—diene (EPDM) polymer, and different types of precipitated calcium carbonate (PCC) were investigated and their properties were analyzed in regard to PCC surface properties and the way of sample preparation (with or without use...

The most important factors that influence the sustainability of the adhesive technology are the sources of raw materials, energy consumption in the production process, and impact on environmental pollution. The usual formulation of the adhesive contains base polymer component derived mostly from non-renewable sources of oil and various other additi...

Improvements in adhesive properties at the interface in nanocomposites, with respect to the standard microcomposites, are a consequence of the great specific surface area of nanofillers and established interactions at nanolevel. An overview of investigations related to the interface and material properties in the conditions of the changed parameter...

The interface in particulate filled polymer systems determine to a large extent, the mechanical and morphological properties of composites and polymer blends. The present contribution describes surface free energy measurements and calculations of adhesion parameters at the interface in poly(vinyl acetate) (PVAc) and polyurethane (PU) composites as...

Polyurethane (PU) and poly(vinyl acetate) (PVAc) are partially miscible polymers. The aim of this study was to investigate the influence of untreated and surface pretreated calcium carbonate (CaCO3) on the interphase properties of PU/PVAc polymer blends with possible compatibilization effects when the conditions of effective adhesion are achieved....

Morphological, mechanical, and Fourier transform infrared dichroic investigations were performed on neat polyurethane (PU) polymer matrix and PU+CaCO3 nanocomposite thin films to determine how the nanofiller influenced the mechanical properties. The measurements were performed on strips that were cut from the prepared films in parallel and perpendi...

In the present paper, the changes at interface between calcium carbonate (CaCO3) and polyurethane (PU) matrix in correlation to the mechanical and morphological properties were investigated. The effect of the untreated CaCO3 microfillers versus nanofillers and/or selected silane pretreatment of nanofiller surface were followed. Correlation between...

Poboljšanje adhezijskih svojstava na međupovršini u nanokompozitima, u odnosu na standardne mikrokompozite, posljedica je velike specifične površine nanopunila i uspostavljenih interakcija na nanorazini. U ovom radu dan je pregled rezultata istraživanja svojstava međupovršine i svojstava materijala u uvjetima promjene parametara adhezije kontrolira...

The adhesion parameters of fillers in composites, coefficient of wetting, interfacial free energy and work of adhesion, were calculated in order to evaluate the difference between the effects of selected microfillers vs nanofillers in polyacrylate (PA) and poly (vinyl acetate)(PVAc) matrix. The results showed that the improved fundamental adhesion,...

In this paper results of the calcium carbonate nanofillers and microfillers addition, as well as influence of the filler surface pre-treatment with stearate and with γ-aminopropyltrietoxysilane (AMPTES) on the properties of the poly(vinyl acetate) and polyurethane composite films respectively, are presented. The results indicate that morphology, fa...

In this work we have investigated the effects of CaCO3 nanofiller pretreatment on the properties of polyurethane (PU) composites prepared by a mixing procedure. The aim was to enhance interactions at the matrix/filler interface and to improve the distribution of the filler in the polyurethane matrix. CaCO3 nanofiller was treated with two different...

Poly(vinyl acetate) (PVAc) composites were prepared by different approaches, namely (i) by mechanical mixing of untreated CaCO3 and PVAc, (ii) by mechanical mixing of CaCO3 pre-treated by irradiation polymerization in the presence of vinyl acetate, and (iii) by in situ emulsion polymerization of VAc in the presence of untreated CaCO3 nanofiller. Th...

Calcium carbonate (CaCO3) is used as filler in poly(vinyl acetate)(PVAc) composites to enhance the mechanical properties. The filler is often commercially surface treated with stearic acid to optimize the interfacial bonding and wetting. The effects of the interface on properties were studied using scanning electron microscopy (SEM) of films with i...

Failure mechanisms of poly(acrylate) (PA) copolymer system filled with a diatom filler have been studied. The natural diatom filler is characterised by the original skeletal structure which allows high "inner" porosity and thus matrix penetration inside the filler particles and agglomerates of various shapes in PA composite. High diatom filler crys...

Polymer composites filled with calcium carbonate (CaCO3) nanofillers (<100 nm), and kaolin filler of layered structure, both well suited to create nanocomposites, were analysed. The aim of this study was to investigate the influence of surface properties of the filler and matrix on the adhesion parameters at the interface in composites. The inverse...

Nanocomposites are expected to exhibit new and improved properties when compared to their microcomposite counterparts. By lowering the particle size to nanodimensions (<100 nm), the special effects in polymer composites appear. In this study we compared the properties of composites filled with micro- and nano-sized calcium carbonate (CaCO3) filler...

The additions of inorganic fillers to the polymer matrix affect the basic mechanical properties of the particulate-filled polymer composites. The tensile properties of the filled polymer composites are more difficult to predict because they depend strongly on the local polymer-filler interactions at the interface, as well as on the other factors. T...

In this paper, a poly(vinyl acetate) (PVAc) adhesive in the form of a film was considered to be a composite. Its mechanical properties changed with filler addition owing to the interactions at the polymer/filler interface. The experimental results were fitted with various theoretical and empirical equations that describe the dependence of mechanica...

Poly(vinyl acetate) (PVAc) composites in the form of films were prepared with CaC03 fillers of different specific surface area. The fillers were commercially surface-treated with stearic acid. Acid-base interactions were found to exert a dominant influence on calcite dispersions in the PVAc matrix. The mechanical properties of these composites vari...

We have studied mechanical and rheological behavior of poly(vinyl acetate) (PVAC) composites filled with calcite as a function of filler particle geometry, particle size distribution, and active surface area. Detailed morphological characteristic were investigated. Tensile properties of PVAC composites were evaluated in the composition range 5–20 w...

In certain applications, a reinforced composite is used as an adhesive layer. In this study, the bulk mechanical behaviour of composite films based on a poly(vinyl acetate) (PVAc) matrix and various calcium carbonate (CaCO3) fillers was investigated. The interactions depend on the morphology and chemical structure of the filler and the polymer matr...

The properties of poly(vinyl acetate) compositions prepared as potential wood adhesives were investigated. The paper presents the results of the influence of various kinds of inorganic fillers based on calcium carbonate and alumino-silicate and an organic filler, starch, on the adhesive composition properties. The comparison among rheological behav...