Wyniki wyszukiwania - Biblioteka Nauki

1

Vibrational spectroscopy investigation of montmorillonite - chitosane nanocomposite materials

100%

Paluszkiewicz C. , Stodolak E.

|

tom Vol. 13, no. 99-101

128

EN

Biomaterials basing on natural polysaccharides, i.e. hiauronic acid, alginate, chitosane are an alternative for already applied bioresorbable synthetic materials basing on synthetic polyhydroxyacids. Their main advantages are good accessibility, low cost, easy forming and high biocompatibility. Additionally, they are a perfect matrix for bioactive nanoparticles i.e. hydroxyapatite (HAp), tricalcium phosphate (TCP) and silica (SiO2). The work presents results of research on nanocomposite consisting of chitosane matrix (CS) modified with a nanofiller, which was natural montmorillonite (MMT). Nanocomposite foils were produced by the casting method. In order to induce better biocompatibility, the surface of the CS/MMT composite was neutralized (bath in NaOH solution). The nanocomposite foils were subjected to a bioactivity test by incubation in SBF at 37oC for 7 days. It was observed that the CS/MMT material surface showed a local supersaturation, which was a result of apatite nucleation. The CS/MMT nanocomposites were investigated using FT-IR (Fourier Transform Infrared Spectroscopy) and Fourier Raman Spectroscopy. FTIR measurements of the samples were carried out on the transmission and reflection modes. The FTIR microscopy spectra were collected using Bio-Rad Excalibur with ATR attachment as well as microscope UMA500 equipped with MCT detector. Spectra were measured at 4 cm-1 resolution in the region from 4000 cm-1 to 600 cm-1. FT-Raman spectra were obtained using a FTS6000 Bio-Rad spectrometer with Ge detector. The samples were excited with a Nd-YAG laser (1064nm). Additional all materials in all steps experiments were observed under Scanning Electron Microscopy (Nova NanoSEM). Vibrational spectroscopy methods (FT Raman and FTIR) can be used for investigation of nanocomposite foils basing on biopolymers. High sensitivity the applied spectroscopy techniques show that in the result of the neutralization of CS/MMT foil (via incubation in NaOH solution) the biopolymer chain breaks. This phenomena is visible by intensity ratio between COC/ COH bands. Increase of reactivity of chitosane chain lead to entrapment of PO43-, which is the origin of the apatite forms nucleation process. Chemical treatment of the nanocomposite foils, i.e. NaOH washes influences their chemical structure and microstructure. Neutralisation of the foils is the first processing stage which precedes the potential use of CS/MMT foils in biomedical applications. The materials show a tendency to apatite crystallisation which may support regeneration of damaged bone tissue. The applied spectroscopic methods allowed to observe changes in the whole volume of the sample. Individual ATR measurements taken at various spectral ranges and penetration depths allow to observe subtle changes in the polymer matrix caused by chemical treatment (NaOH and SBF incubation). Results of the investigations indicate that in the CS/ MMT systems new chemical bonds and related to them vibrations appear. Quantity and quality of the interactions is related to characteristics of the nanoparticle and the presence of forming apatite structures.

2

Vibrational spectroscopy investigation of montmorillonite-chitosane nanocomposite materials

100%

Paluszkiewicz C. , Stodolak E.

|

tom Vol. 14, no. 109-111 spec. iss.

44

EN

Biomaterials basing on natural polysaccharides, i.e. hiauronic acid, alginate, chitosane are an alternative for already applied bioresorbable synthetic materials basing on synthetic polyhydroxy acids. Their main advantages are good accessibility, low cost, easy forming and high biocompatibility. Additionally , they are a perfect matrix for bioactive nanoparticles i.e. hydroxy apatite (HAp), tricalcium phosphate (TCP) and silica (SiO2). The work presents results of research on nanocomposite consisting of chitosane matrix (CS) modified with a nanofiller, which was natural montmorillonite (MMT). Nanocomposite foils were produced by the casting method. In order to induce better biocompatibility, the surface of the CS/MMT composite was neutralized (bath in NaOH solution). The nanocomposite foils were subjected to a bioactivity test by incubation in SBF at 37oC for 7 days. It was observed that the CS/ MMT material surface showed a local supersaturation, which was a result of apatite nucleation. The CS/ MMT nanocomposites were investigated using FT-IR ( Fourier Transform Infrared Spectroscopy) and Fourier Raman Spectroscopy. FTIR measurements o f the samples were carried out on the transmission and reflection modes. The FTIR microscopy spectra were collected using BioRad Excalibur with ATR attachment as well as microscope UMA500 equipped with MCT detector. Spectra were measure at 4 cm -1 resolution in the region from 4 000 cm -1 to 600 cm -1 . FT-Raman spectra were obtained using a FTS 6000 Bio-Rad spectrometer with Ge detector. The samples were excited with a Nd-YAG laser (1064nm). Additional all materials in all steps experiments were observed under Scanning Electron Microscopy (Nova Nano SEM). Vibrational spectroscopy methods (FT Raman and FTIR) can be used for investigation of nanocomposite foils basing on biopolymers. High sensitivity the applied spectroscopy techniques show that in the result of the neutralization of CS/ MMT foil (via incubation in NaOH solution the biopolymer chain breaks. This phenomena is visible by intensity ratio between COC/COH bands. Increase of reactivity of chitosane chain lead to entrapment of PO4+3-, which is the origin of the apatite forms nucleation process. Chemical treatment of the nanocomposite foils, i.e. NaOH washes in fluences their chemical structure and microstructure. Neutralisation of the foils is the first processing stage which precedes the potential use o fCS/ MMT foils in biomedical applications. The materials show a tendency to apatite crystallisation which may support regeneration of damaged bone tissue. The applied spectroscopic methods allowed to observe changes in the whole volume of the sample. Individual ATR measurements taken at various spectral ranges and penetration depths allow to observe subtle changes in the polymer matrix caused by chemical treatment (NaOH and SBF incubation). Results of the investigations indicate that in the CS/ MMT systems new chemical bonds and related to them vibrations appear. Quantity and quality of the interact ions is related to characteristics of the nanoparticle and the presence of forming apatite structures.

3

Otrzymywanie i ocena właściwości nanokompozytów PVC/MMT wytwarzanych metodą rozpuszczalnikową

75%

Pagacz J. , Pielichowski K.

|

2009

|

tom R. 106, z. 1-Ch

95-110

PL

W niniejszym artykule opisano preparatykę i analizę nanokompozytów PVC/MMT wytwarzanych metodą rozpuszczalnikową. Stosowano suspensyjny PVC i nanonapełniacze - naturalny oraz organicznie modyfikowany montmorylonit, a także, jako rozpuszczalnik, cykloheksanon. W celu scharakteryzowania struktury otrzymanych materiałów wykorzystano spektroskopię FTIR oraz metodę WAXD, natomiast wpływ nanonapełniacza na stabilność termiczną nanokompozytów PVC/MMT sprawdzano metodą termograwimetryczną (TG).

EN

In this work results of preparation and analysis of PVC/MMT nanocomposites were presented. The nanocomposites were obtained by the solution casting method, using suspensive PVC and nanofillers - the natural and organically-modified montmorillonite. Cyclohexanone was used as a solvent. The structure of nanomaterials obtained was studied by FTIR and WAXD methods. Thermal stability of PVC/MMT nanocomposites was characterized using thermogravimetric method (TG).

4

The MWCNTs-Rh Nanocomposite Obtained By The New High-Temperature Method

63%

Dobrzańska-Danikiewicz A. D. , Cichocki D. , Łukowiec D.

Archives of Metallurgy and Materials

|

2015

|

tom Vol. 60, iss. 2A

1057--1063

EN

A nanocomposite was fabricated during the research undertaken, consisting of multiwalled carbon nanotubes coated with rhodium nanoparticles by the new high-temperature method being the subject of the patent claim. High quality multiwalled carbon nanotubes (MWCNTs) with the length of 100÷500 nm and the diameter of 8÷20 nm obtained in advance with Catalytic Chemical Vapour Deposition (CVD) were employed in the investigations. The nanotubes manufactured under the own research contain small amounts of metallic impurities and amorphous carbon deposits. Multiwalled carbon nanotubes functionalisation in acids was applied to deposit rhodium nanoparticles onto the surface of carbon nanotubes, and then the material was placed in a solution being a precursor of rhodium nanoparticles. The material prepared was next placed in a quartz vessel and subjected to high-temperature reduction in the atmosphere of argon to deposit rhodium nanoparticles onto the surface of multiwalled carbon nanotubes. The following examinations were performed, respectively: MWCNTs fabrication, fabrication of a CNT-NPs (Carbon NanoTube-NanoParticles) nanocomposite material; the characterisation of the materials produced including examination of the structure and morphology, and the assessment of rhodium nanoparticles distribution on the surface of carbon nanotubes. Micro- and spectroscopy techniques were employed to characterise the structure of the nanocomposites obtained.

PL

W ramach wykonanych badań wytworzono nanokompozyt składający się z wielościennych nanorurek węglowych pokrytych nanocząsteczkami rodu nową wysokotemperaturową metodą, będącą przedmiotem zgłoszenia patentowego. W badaniach wykorzystano wysokiej jakości wielościenne nanorurki węglowe MWCNTs o długości 100÷500 nm i średnicy 8÷20 nm uprzednio otrzymane w procesie katalityczno-chemicznego osadzania z fazy gazowej (CCVD). Wytworzone w ramach prac własnych nanorurki zawierają nieznaczne ilości zanieczyszczeń metalicznych i amorficznych depozytów węglowych. W celu osadzenia nanocząsteczek rodu na powierzchni nanorurek węglowych zastosowano funkcjonalizację wielościennych nanorurek węglowych w kwasach, następnie materiał umieszczono w roztworze będącym prekursorem nanocząsteczek rodu. Przygotowany materiał umieszczono w dalszej kolejności w kwarcowym naczyniu i poddano redukcji wysokotemperaturowej w atmosferze argonu w celu osadzenia nanocząsteczek rodu na powierzchni wielościennych nanorurek węglowych. Wykonane badania obejmują kolejno: wytworzenie MWCNTs, wytworzenie materiału nanokompozytowego typu nanorurki węglowe – nanocząsteczki (CNT-NPs), scharakteryzowanie wytworzonego materiału obejmujące badanie jego struktury i morfologii oraz ocenę rozmieszczenia nanocząsteczek rodu na powierzchni nanorurek węglowych. Dla scharakteryzowania struktury otrzymanych nanokompozytów zastosowano techniki mikro- i spektroskopowe.

5

Nowe materiały dla bezpilotowych aparatów latających

63%

Chatys R. , Koruba Z. , Kleinhof M.

|

tom Z. 80

77-83

PL

W artykule przedstawione są rozważania na temat możliwości zastosowania w mikrobezpilotowym aparacie latającym (MBAL) nowych materiałów konstrukcyjnych. Zostały zamodelowane fizyko-mechaniczne własności komponentów kompozytu węglowego PAN i nanokompozytu poprzez metodę statystyczną.

EN

In the paper are presented the considerations on the possibilities of using In micro unmanned serial vehicle (MUAV) of new materials construction. The authors reveal the interdependence of the components of the PAN carbon composite and nanocomposite in the statistical aspects by studying the physical and mechanical properties of the components