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Chitosan is a natural polymer obtained by deacetylation of chitin. Due to its biocompatibility and biodegradability, chitosan-based materials have a wide range of biomedical applications in wound dressings, drug delivery systems, and tissue engineering. Also, studies in the fields of organic and medicinal chemistry show that compounds based on the pyridone core exhibit biological properties including antimicrobial, anticancer, and antioxidant activity, and moreover have the potential as new therapeutics for various diseases from cardiovascular to antitumor therapy. In this study, new biomaterials were synthesized using low and medium molecular weight chitosan polymers and pyridone-based hydrazone. In order to improve stability of the obtained scaffolds, scaffolds’ neutralization was carried out using ethanol and sodium hydroxide solutions. The interactions established between chitosan polymer chains and pyridone compound were analyzed by FT-IR spectroscopy. Swelling and degradation tests of the materials were studied in water and PBS, and the influence of different polymer molecular weights on the scaffolds’ properties was evaluated. The results indicated that synthetized scaffolds have a high potential for biomedical use.

Purpose:Even though various types of scaffolds have been used lately as a complement to microfracture, the exact mechanism of reported cartilage repair improvement when using scaffolds is still unclear. In this study, an effort has been made to identify the specific effects that scaffolds may have on the cells of reparation when using this technique.Methods:A 3‑D model in vitro, representing microfracture and containing both chondrocytes and bone marrow‑derived cells in different experimental conditions was made, and the cells were cultured for eight weeks. Subse‑quently, the constructs containing our 3‑D model were removed from the cell culture medium, fixed in paraffin and analyzed with immunohistochemistry.Results:Bone marrow – derived cells migrated to the upper compartment of the construct through a perforated nylon membrane containing both enzymatically digested‑ and non‑digested particulated cartilage. The histological sections were stained with hematoxylin, eosin, S‑100, SOX‑9, Gomori, and procollagen type I and II. When minced cartilage wasn’t pretreated with collagenase, exclusively bone‑derived cells have created new extracellular matrix as showed by the histological analysis.Conclusions:In this model of microfracture, bone‑derived cells but not chondrocytes have shown to have an active role in new cartilage formation without predigestion with collagenase. Moreover, it seems that the addition of a chitosan‑based scaffold may lead to the improvement of a new cartilage matrix synthesis and integration. This effect hasn’t been seen without the use of scaffold or when a fibrin‑ or a collagen‑based scaffold have been used.

Producing green and efficient energy sources is a major challenge. As a consequence, the use of photovoltaic devices for conversion of light into electricity is growing worldwide. A lot of effort had been invested to create high-efficient solar cells, but their durability, stability, flexibility and efficiency at low light intensities are still unexplored. Here, we built a flexible solar cell made of p-doped, amorphized a-undoped and n-doped Sb2S3 solid carrier loaded with electrolyte. Indium tin oxide glass was the working electrode, and aluminium was the counter electrode. Every (p-a-n) flexible Sb2S3/solid carrier layers were obtained using a cheap casting/solvent evaporation technique, from a blend consisted of chitosan, polyethylene glycol and electrolyte containing 0.5 M potassium iodide and 0.05 M iodine, and corresponding synthesized amorphized a-undoped and p and n-doped Sb2S3 semiconductor. Results show that flexible Sb2S3 solar cell possesses good stability and efficiency of about 10% at 5% sun. Overall, our findings demonstrate for the first time that flexible solar cell can be made and used for low light intensity applications.

We present here a novel solar cell made of ITO/composite p-doped Sb2S3 + P3HT + PANI + TiO2/amorphous Sb2S3+P3HT+PANI+TiO2/n-doped Sb2S3 + P3HT + PANI + TiO2/solid carrier/aluminum as counter electrode. With spraying technique, the layers were deposited and the thickness of films was 1m. A new solid carrier of electrolyte was a blend consisted of chitosan (low MW), polyethylene glycol and electrolyte. X-ray diffraction was recorded to confirm the amorphous nature of the blend. Information about the surface appearance and roughness of a solid carrier dry and soaked in the electrolyte was given by atomic force microscopy. The solar cell was examined at very low and low light intensity (5% and 35% of sun, respectively), and at standard test conditions (100% of sun) using different light sources. The whole cell surface was 7.5cm(2) while the illuminated part was 3cm(2). Obtained results expressed for the illuminated surface showed the highest efficiency of 23.1% at 5% of sun while the efficiency of the cell was 2.9% at 35% of sun and only 0.75% at intensity of 100% of sun.

Nanokompozitni hidrogelovi imaju potencijal primene u biomedicini za kontrolisano oslobaĎanje bioaktivnih komponenata. Razvoj koncepta hidrogel nanokompozita podrazumeva unapreĎenje fizičkohemijskih, mehaničkih i antibakterijskih svojstava u cilju rešavanja aktulenog problema rezistencije na antibiotike.Za sintezu hidrogel nanokompozita odabrani su poli(vinil alkohol) (PVA) i antibakterijske komponente: nanočestično srebro (Ag) i vodorastvorni hitozan (vr-CS)..., Nanocomposite hydrogels have the potential for biomedical applications for the controlled release of bioactive components. The development of the concept of hydrogel nanocomposites involves improving the physicochemical, mechanical and antibacterial properties in order to solve the problem of antibiotic resistance.Materials that were chosen for the synthesis of the hydrogel nanocomposites are poly(vinyl alcohol) (PVA) and antibacterial components: silver (Ag) nanoparticles and a water-soluble chitosan (ws-CS)...

To produce well-defined metal clusters stabilized in protective matrix, poly(N-isopropylacrylamide) (PNi-PAAm) hydrogel with different initial concentration of polymer was used as nanoreactor. The in situ synthesis of well dispersed silver nanoparticles (AgNPs) was performed by gamma irradiation. The obtained AgNPs are spherical in shape with the diameter less than 20 nm. Crystalline properties of nanoparticles such as size, texture coefficient, strain, stress, lattice parameter, d-spacing, and dislocation density have been calculated using XRD data. Results confirm that the changes of lattice parameter of crystalline AgNPs sensitively reflect their state of strain and stress depending on the formation conditions (i.e., on the concentration of PNiPAAm) and on the diameter of AgNPs. The negative lattice strain and compression stress were observed for the smaller AgNPs (lattice contraction), while for the larger AgNPs are positively strained and under tensile stress (lattice expansion). XPS spectra revealed the donor-acceptor type of interaction between carbonyl oxygen from PNiPAAm and AgNPs (positive shift of high BE component of O 1s and negative shift of Ag 3d BE). The greater dislocation density of smaller AgNPs incorporated in more concentrated PNiPAAm, resulted in more binding sites and stronger interaction with polymer.

We report here on an inexpensive, solid and stable solar cell designed and made entirely of synthesized materials, Sb2S3/ hypericin (dye) thin film on ITO-coaled glass (working electrode), aluminum (counter electrode), and PVA matrix (solid carrier) loaded, with electrolyte (0.5M KI+ 0.05M I-2). The fact, that the cell is inexpensive, hut also stable and. solid, with efficiency of around 1.3%/cm(2) at a very low light intensity of only 5% sun, makes it particularly suitable for indoor applications. At higher light, intensities of 25 and 55% sun, however, the cell exhibits lower efficiency, around 0.3 and 0.07%/cm(2), respectively. Development of low-cost cell technology combined with understanding of low light utilization and, setting of standard conditions should be some of the future directions the research in this area should, follow. Therefore, in this work, we tried to give sufficient reasons for establishing standard conditions related to low light, intensity. (C) 2017 American Institute of Chemical Engineers.

Monitoring bromides (Br-) is of crucial importance since bromates, potential human carcinogens, are formed during ozonation of water containing bromides in concentrations GT 100 mu gL(-1). Within this study, silver (Ag) and four carbon-supported Ag catalysts were synthesized by the gamma-radiation method and their morphology and structure examined using transmission electron microscopy, X-ray diffraction, and UV-Vis analysis. The nanocatalysts were tested for Br- sensing in aqueous media using cyclic voltammetry. All five Ag materials exhibited electroactivity for sensing of Br- ions, with pure Ag catalyst giving the best response to Br- ions presence in terms of the lowest limit of detection. Sensing of bromides was also explored in tap water after addition of bromides suggesting that herein prepared catalysts could be used for bromides detection in real samples. Furthermore, sensing of other halogen ions, namely, chlorides and iodides, was examined, and response due to chloride presence was recorded.

U okviru ove doktorske disertacije izvedena je radijaciono-hemijska sinteza i karakterizacija novih nanokompozita na bazi umreţenih polimernih matrica N-izopropilakrilamida (NiPAAm) i itakonske kiseline (IK) i nanočestica srebra (Ag/P(NiPAAm/IK)). Za sintezu nanokompozita je korišćena radiolitička metoda koja omogućava umreţavanje i fino podešavanje svojstava nosača tj. polimerne matrice, ali i formiranje nanočestica srebra ţeljenih svojstava unutar polimerne matrice (in situ sinteza). Radiolitička metoda sinteze je izvedena pod dejstvom gama zračenja na kobaltnom (60Co) izvoru. Sintetisani uzorci su podvrgnuti detaljnoj fizičko-hemijskoj karakterizaciji u cilju dobijanja informacija o polimernim matricama kao nosačima i nanočesticama srebra kao nanopuniocima, ali i u cilju ispitivanja njihovog sinergističkog dejstva u nanokompozitnim sistemima.Morfologija umreţenih sistema je ispitana primenom skenirajuće elektronske mikroskopije (SEM) i mikro kompjuterizovane topografije (mikro-CT), a studija bubrenja praćenjem kinetike bubrenja u medijumima različitih pH-vrednosti i temperature, pri čemu su simulirani fiziološki uslovi. Utvrđeno je da prisustvo itakonske kiseline i inkorporacija nanočestica srebra utiču na morfologiju nanokompozita, parametre polimerne mreţe, kao i na kapacitet bubrenja.Optička svojstva nanokompozita su ispitana metodom spektroskopije u ultraljubičastoj i vidljivoj oblasti spektra (UV-Vis) i teorijskim modelovanjem primenom MiePlot 3.4 programskog paketa čiji je algoritam zasnovan na Mie-ovoj teoriji. U apsorpcionim spektrima je zapaţena karakteristična plazmonska apsorpcija sa maksimumom u opsegu od 390 nm do 412 nm, dok jemodelovanjem određeno da se vrednost prečnika nanočestica srebra kreće između 6,8 nm i 16,2 nm..., In this study, radiation-chemical synthesis and characterization of the novel nanocomposite systems based on silver nanoparticles (AgNPs) and crosslinked copolymer matrix of N-isopropylacrylamide (NiPAAm) and itaconic acid (IA) (Ag/P(NiPAAm/IA)) were performed. Radiolytic method, which is used for synthesis, enables fine tuning of properties of polymer matrix as a carrier, as well as formation of the silver nanoparticles with desired properties within polymer matrix (in situ synthesis). The radiolytic synthesis method is carried out by gamma irradiation at a cobalt (60Co) radiation facility. Synthesized samples were undergo to detailed physico-chemical characterization in order to obtain information about polymer matrix as a carrier and silver nanoparticles as a nanofillers, but also to examine their synergistic effects in the nanocomposite systems.Morphology of the crosslinked systems was performed by scanning electron microscopy (SEM) and micro computerized topography (micro-CT), while swelling study was performed by monitoring the swelling kinetics in the swelling media with different pH and temperature, i.e. in simulated physiological conditions. It has been shown that the addition of itaconic acid and incorporation of AgNPs have influences on the morphology, network parameters as well as on the swelling capacity.The optical properties of the nanocomposites were investigated by ultraviolet–visible spectroscopy (UV-Vis) and theoretical modeling using MiePlot 3.4 software package, with algorithm based on Mie's theory. Obtained absorption spectra exhibit the characteristic plasmon peak with maximabetween 390 nm and 412 nm, while the modeling has shown that the mean size of the silver nanoparticles was in the range between 6.8 nm and 16.2 nm...

Carbon-supported silver nanoparticles (Ag:NPs/C) were synthesized by gamma irradiation-induced reduction method using the poly(vinyl alcohol) or poly(vinyl alcohol)/chitosan polymer as stabilizer. Prepared samples were characterized using transmission electron microscopy and X-ray diffractometry. Subsequently, Ag:NPs/C were studied using rotating disc and rotating ring disc method as electrocatalysts for ORR (oxygen reduction reaction) and BOR (borohydride oxidation reaction) for potential application in alkaline fuel cells. The synthesis method used herein offers simple and fast approach for catalytic ink preparation, since the ink is prepared in one-step radiation process, simultaneously with Ag+ ions reduction. Very high and stable catalytic efficiency toward ORR via 4e(-) path was evidenced during 4000 square pulse polarization cycles. BOR, accompanied with the simultaneous borohydride ion hydrolysis, was found to proceed at the oxidized Ag surface. (C) 2016 Elsevier Ltd. All rights reserved.

Thermo- and pH-sensitive Ag-P(NiPAAm/IA) hydrogel nanocomposites were prepared by in situ reduction of Ag+ ions with gamma irradiation. P(NiPAAm/IA) copolymer hydrogel matrices have been previously synthesized by radiation induced copolymerization. The copolymer composition was determined by elemental analysis of the dried gels, and was found to be close to that of the feed. The dependence of swelling properties and phase transitions on the IA comonomer content, temperature, pH values and presence of AgNPs were investigated. The hydrogels showed both thermo- and pH responses. By introducing small amounts of IA, swelling capacity increase, and the volume phase transition temperature (VPIT) of P(NiPAAm/IA) copolymers is transferred to higher values. Presence of AgNPs causes decrease of equilibrium swelling degree and VPIT, and allows of fine-tuning of these properties. Both the average values of compressive elastic modulus and Young's modulus of elasticity were decreased by addition of IA as a consequence of looser structure of the network (increase in molar mass between two neighboring crosslinks and decrease in effective crosslinking density). The introduction of AgNPs promoted not only improvement of these mechanical parameters, but an improvement of stress at failure especially in the systems with the highest content of IA. In addition, Ag-P(NiPAAm/IA) hydrogel nanocomposites showed good antibacterial potentials.

PVA (Poly(vinyl alcohol)) matrixes were developed for potential application in electrochemical energy conversion devices, like batteries, alkaline fuel cells and electrolyzers. They were prepared by gamma-irradiation of aqueous PVA solutions, followed by different post irradiation treatments. By immersion in an electrolyte they become membranes with high ionic conductivities. The treatments were shown as the key factor determining the conductivity, through affecting their structure. An improved structure has large fractional free volume, and allows high electrolyte uptake and thus high conductivity (0.30 S cm(-1) -0.34 S cm(-1)). The structure, as well as the conductivity, has not been changed even after a period of 14 months, although the membranes have been exposed to strong alkaline medium. Besides high and long-term conductivity of the KOH doped membranes, other important properties for application in the devices were investigated, like thermal stability and gas crossover through the membranes. The 10% PVA(25kGy) membrane doped with saturated LiNO3 solution was tested in a rechargeable aqueous Li-ion battery. Due to its high conductivity it allowed an electrode material to have the same coulombic efficiency as it would have in liquid LiNO3, showing good compatibility with the material. All these properties make the memebranes attractive candidates for possible application in the electrochemical devices. (C) 2015 Elsevier Ltd. All rights reserved.

A nanosilver (nano-Ag)/poly(vinyl alcohol) (PVA) hydrogel device was synthesized with irradiation because it is a highly suitable tool for enhanced nano-Ag technologies and biocompatible controlled release formulations. The amount of the Ag+ ions released in vitro by the nano-Ag/PVA hydrogel device was in the antimicrobial parts per million concentration range. The modeling of the Ag+ ion release kinetics with the elements of the drug-delivery paradigm revealed the best fit solution (R-2 gt 0.99) for the Kopcha and Makoid-Banakar's pharmacokinetic dissolution models. The term A/B, derived from the Kopcha model, indicated that the nano-Ag/PVA hydrogel was mainly an Ag+-ion diffusion-controlled device. Makoid-Banakar's parameter and the short time approximated Ag+-ion diffusion constant reflected the importance of the size of the Ag nanoparticles. However, it appeared that the cell oxidation potential of the Ag nanoparticles depended on the diffusion characteristics of the fluid penetrating into the Ag/PVA nanosystem.

Silver nanoparticles were produced inside a poly(N-vinyl-2-pyrrolidone) hydrogel (PVP) by an innovative method based on the electrochemical reduction of Ag+ ions within the swollen PVP hydrogel. UV-visible spectroscopy showed the highest value of the absorbance intensity and the lowest values of the wavelength of the absorbance maximum and the full width at the half-maximum absorbance for the Ag/PVP nanocomposite obtained at 200 V during 4 min. Cyclic voltammetry results suggested an adequate entrapment of the silver nanoparticles. The mechanical properties under bioreactor conditions of the Ag/PVP nanocomposite suggested the possibility of wound dressing application. Silver release from Ag/PVP nanocomposites was confirmed under static conditions as well as by their antimicrobial activity against Staphylococcus aureus. POLYM. COMPOS., 35:217-226, 2014.

A nanosilver (nano-Ag)/poly(vinyl alcohol) (PVA) hydrogel device was synthesized with irradiation because it is a highly suitable tool for enhanced nano-Ag technologies and biocompatible controlled release formulations. The amount of the Ag+ ions released in vitro by the nano-Ag/PVA hydrogel device was in the antimicrobial parts per million concentration range. The modeling of the Ag+ ion release kinetics with the elements of the drug-delivery paradigm revealed the best fit solution (R-2 GT 0.99) for the Kopcha and Makoid-Banakars pharmacokinetic dissolution models. The term A/B, derived from the Kopcha model, indicated that the nano-Ag/PVA hydrogel was mainly an Ag+-ion diffusion-controlled device. Makoid-Banakars parameter and the short time approximated Ag+-ion diffusion constant reflected the importance of the size of the Ag nanoparticles. However, it appeared that the cell oxidation potential of the Ag nanoparticles depended on the diffusion characteristics of the fluid penetrating into the Ag/PVA nanosystem. (c) 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40321.

In this study, the potential of chitosan/poly(vinyl alcohol) (CS/PVA) blends as capping agent for stabilization of Ag-nanoparticles (Ag NPs) during their in situ gamma irradiation induced synthesis was investigated. The UV-vis absorption spectra show the surface plasmon absorption band around 410 nm, which confirms the formation of Ag-nanoparticles. It was found that the composition of CS/PVA blend affected the size of the obtained Ag-nanoparticles, as well as the parameters such as density, molar concentration and effective surface area, calculated from the experimentally obtained UV-vis absorption spectra and spectra obtained by simulation according to the Mie theory. SEM micrograph and XRD measurement indicated a spherical morphology and face centered cubic crystal structure of Ag-nanoparticles, with diameter around 12 nm. The values of optical band gap energy between valence and conduction bands (E-g), calculated from the UV-vis absorption spectra, also show dependence on the blend composition for Ag-CS/PVA colloids as well as for Ag-CS/PVA nanocomposites. (C) 2013 Elsevier Ltd. All rights reserved.

Magnetic field sensitive gels, ferrogels, are new promising class of hydrogels. The coupling of hydrogels and magnetic particles has potential application in soft actuators, such as artificial muscles, or for hyperthermia application. In this study, the composite of magnetite particles (Fe3O4) and poly(vinyl alcohol) (PVA) hydrogel is developed using gamma irradiation as a crosslinking agent. PVA and Fe3O4 were chosen due to their well-established biocompatibility, radiation crosslinking potential (PVA), mild magnetic properties and the Curie point near desired heating temperature range (Fe3O4). Physicochemical characteristics of these systems show the effect of the presence of particles in the process of radiation-induced crosslinking. Obtained PVA/Fe3O4 ferrogel composite has greater swelling capacity, activation energy of dehydration and dehydration rate compared to PVA hydrogel, crosslinked under the same conditions.

The optical properties of 150 keV N+ implanted ethylene-norbornene (TOPAS 6017S-04) copolymer were investigated using phase modulated spectroscopic ellipsometry (PMSE) and ultraviolet-visible (UV-Vis) spectroscopy in the ranges of 0.6-6.5 eV and of 1.5-6.2 eV, respectively. The single-effectiveoscillator model was used to fit the calculated data to the experimental ellipsometric spectra. The results show that the oscillator and dispersion energies decrease with increasing ion fluence up to 10(15) cm(-2), and then these parameters increase with further fluence increasing. Analysis of the UV-Vis absorption spectra revealed the presence of indirect electronic transitions with the band gap energy in the range of 1.3 to 2.8 eV. It was found that both the band gap energy and the energy width of the distribution of localized band tail states decrease, while the values of Tauc coefficient increase with increasing the ion fluence. From the ellipsometric data we found that the real part of the dielectric function increased about 7% after irradiation with 10(15) cm(-2), and decreased about 10% in samples modified with 10(16) cm(-2).

Silver/poly(N-vinyl-2-pyrrolidone) (Ag/PVP) nanocomposites containing Ag nanoparticles at different concentrations were synthesized using gamma-irradiation. Cytotoxicity of the obtained nanocomposites was determined by MU assay in monolayer cultures of normal human immunocompetent peripheral blood mononuclear cells (PBMC) that were either non-stimulated or stimulated to proliferate by mitogen phytohemagglutinin (PHA), as well as in human cervix adenocarcinoma cell (HeLa) cultures. Silver release kinetics and mechanical properties of nanocomposites were investigated under bioreactor conditions in the simulated body fluid (SBF) at 37 degrees C. The release of silver was monitored under static conditions, and in two types of bioreactors: perfusion bioreactors and a bioreactor with dynamic compression coupled with SBF perfusion simulating in vivo conditions in articular cartilage. Ag/PVP nanocomposites exhibited slight cytotoxic effects against PBMC at the estimated concentration of 0.4 mu mol dm(-3), with negligible variations observed amongst different cell cultures investigated. Studies of the silver release kinetics indicated internal diffusion as the rate limiting step, determined by statistically comparable results obtained at all investigated conditions. However, silver release rate was slightly higher in the bioreactor with dynamic compression coupled with SBF perfusion as compared to the other two systems indicating the influence of dynamic compression. Modelling of silver release kinetics revealed potentials for optimization of Ag/PVP nanocomposites for particular applications as wound dressings or soft tissue implants.

The aim of this study is to evaluate the size and stability of radiolytically produced silver clusters. The clusters obtained by the gamma irradiation of a mixture of a silver salt and polyvinyl alcohol (PVA) were studied both theoretically and by mass spectrometry. MALDI TOF mass spectrometry of the Ag-n clusters showed the presence of clusters containing between 5 and 29 atoms. Both the theoretical and experimental results of this paper show that the most stable clusters are small clusters with an odd number of atoms. The stability of these clusters is correlated with the clusters electronic configuration. (C) 2012 Elsevier Ltd. All rights reserved.

In this study, the non-isothermal kinetics of dehydration of γ-radiolytically synthesized PVA and Ag/PVA nanocomposite hydrogels was investigated by thermogravimetric analysis (TGA). Kinetic analysis was performed by applying different model fitting and model-free kinetic analysis to estimate kinetic parameters, the activation energy (Ea) and pre-exponential factor (A). The analysis showed that incorporation of silver nanoparticles (Ag NPs) into PVA hydrogel matrix has influence on kinetic parameters of dehydration process.

Silver nanoparticles (AgNPs) were synthesized in situ by gamma-irradiation using poly(N-vinyl-2-pyrrolidone) (PVP) as a capping agent. The concentration, molecular weight and the structure (crosslinked and interpenetrated network) of PVP were varied, in order to determine the influence of the capping agent in the radiolytic synthesis of the Ag/PVP nanosystems. Transmission electron microscopy (TEM) showed that AgNPs obtained from the solutions containing higher PVP concentration and higher molecular weight were spherical in shape, with narrow size distribution and a diameter of similar to 6 nm, while slightly larger rod-shaped silver agglomerates, with bimodal nanoparticle size distribution and diameters of similar to 10 nm and similar to 20 nm were obtained from the solutions containing lower PVP concentration and lower molecular weight. Strong plasmon coupling and extending of plasmon resonance was observed by UV-vis spectroscopy, as a result of formation of nanorod-like agglomerates. Crosslinked and interpenetrated network did not affect the structure of synthesized AgNPs. Ag/PVP nanocomposite, in the form of thin film, was obtained by solvent evaporation from Ag/PVP colloid solution with 10 wt% of PVP, and characterized by FTIR spectroscopy. The interactions in Ag/PVP nanocomposite are shown to be the result of the coordination bonding between AgNPs and nitrogen from pyrrolidone ring of PVP. The optical properties of investigated Ag/PVP nanosystems, as measured by the values of optical band gap, E-g, are mainly the consequence of the interparticle distance as a result of the concentration and the structure of surrounding PVP macromolecules.

Gamma-irradiation induced reduction of gold (Au) ions was performed in aqueous poly(vinyl alcohol) (PVA) solution. PVA/Au nanocomposites with different contents of inorganic phase were prepared by solvent evaporation. The colloids and corresponding nanocomposites show visible light absorption with strong excitonic peak in the wavelength range from 520 to 550 nm. Morphological and structural characterizations of gold nanoparticles (Au NPs) and nanocomposites were performed by TEM, XRD, and FTIR measurements. Also, Mie and Maxwell-Garnett theories were applied to calculate optical properties of Au colloids and PVA/Au nanocomposites, respectively. The changes of heat resistance upon the increase of inorganic phase were correlated to the decrease in crystal perfection of polymer. Improvement of thermal stability of nanocomposites, compared with the neat PVA, was observed when the content of inorganic phase exceeds 1 wt %. (c) 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012