materiale de acoperire organo-anorganice nanostructurate

8/10/2019 Materiale de Acoperire Organo-Anorganice Nanostructurate

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E. Crciun, A. Ioncea, I. Jitaru, M. Ghiurea, O. Oprea / Materiale de acoperire organo-anorganice nanostructurate 65

este necesarprevenirea separrii celor doufaze.n acest scop au fost utilizate particule

anorganice tratate cu ageni de cuplare siloxanici.Modificarea nanoparticulelor cu ageni de cuplareimplicprocese sol-gel [3] care cuprind reacii de:

to prevent the separation of organic and inorganicmaterial in the mixture. For this, the treatment ofinorganic particles with coupling agents of siloxanetype was used.

The modification of nanoparticles using thesiloxane coupling agent involves the sol-gelprocess [3] which consist in some reactions:

- Hidroliz/ hydrolysis

(1)

- condensare la oligomeri / condensation to oligomers

3 RSi(OH)3

DTOH Si O

OH

Si

OH

O Si OH

R R R

OH

+ 2 OH2

(2)

- formare delegturi de hidrogen ntre gruprile OH ale suportului (nanoparticule) i gruprile OH ale

oligomerilor / the formation of hydrogen bond between OH groups of substrate (nanoparticles) andOH groups of oligomers

OH Si O

OH

Si

OH

O Si OH

R R R

OH

OH OH OHO

H H

O

H H

O

H

OH Si O

O

Si

O

O Si OH

R R R

O

H

- OH2

DT

Surface

Nanoparticle

Surface

Nanoparticle

Hydrogen bonding

(3)

- formare de legturi covalente cu substratul prin pierdere de apn timpul uscrii- covalent bonds formation : covalent links are formed with the substrate (by the water loss during the

drying)

OH Si O

O

Si

O

O Si OH

R R R

O

Surface (4)

R este un radical organic nehidrolizabil careconine grupri funcionale prin intermediul croracupleaz cu polimerul organic, realiznd legturantre partea anorganic (nanofiler) i parteaorganic.

Datorit sinergiei celor dou faze, filmuluscat de nanocompozit posed dou reeleinterpenetrate: faza soft a prii formatoare defilm (polimer) i faza dur non-formatoare de film,reprezentat de materialul anorganic carerealizeaz de obicei mbuntirea proprietilorfilmului.

n NC, proprietile polimerului caelasticitate, flexibilitate, proprietile optice (luciu i

R is a nonhydrolyzable organic radical thatcontains a functionality which enable the couplingagent to bond with organic resins creating thebridge between inorganic (nanofiller) and organicpart of nanocomposite.

Due to the sinergy of two phases, the dry filmof nanocomposite posses two interpenetratednetworks: the soft - film forming polymer phaseand a hard non-film forming inorganic domain withthe advantage in improvement of the filmproperties.

In NC, the properties of soft polymer like

elasticity, flexibility, optical aspects (glosy andtransparency) are combined with the antagonistic

RSi(OCH3)3+ 3 OH2 RSi(OH)3 + 3CH3OH


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66 E. Crciun, A. Ioncea, I. Jitaru, M. Ghiurea, O. Oprea / Organo-inorganic nanostructurated coating materials

transparen) sunt combinate cu caracteristicilefazei dure anorganice ca, rezisten la abraziune,duritate, stabilitate termici rezistenchimic.

n mod obinuit aceste proprietiantagoniste nu se ntlnesc mpreun nici nvopselele convenionale diluabile cu ap (frnanofileri) nici n vopselele diluabile cu ap care

conin fileri micronizai.n aceast lucrare este obinut un material

nanocompozit (produs de acoperire peliculogenhibrid, cu structurnanocompozitic), care prezintproprieti mecanice i electrice mbuntite ncomparaie cu acoperirile organice tradiionalediluabile cu ap.

2. Partea experimental

2.1. Prepararea dispersiei de nanocompozit(formulrile 1-5)

Pentru a investiga i compara proprietileunor lacuri transparente (acoperiri peliculogeneavnd structur de nanocompozit) cu acoperirilepeliculogene acrilice convenionale au fostrealizate mai multe variante (formulri) de lacuri.

Toate variantele de acoperire peliculogeninvestigate, au fost preparate utiliznd:

- dispersie anionic de copolimer acrilic cuautoreticulare, coninnd grupri funcionale COOH i avnd morfologie core-shell [4];

- nanofiler : silice coloidal cu dimensiunemedie 7-25 nm i suprafa modificat cuepoxisilan, RSi(OCH3)3(unde R=glicidoxipropil) [4];

- agent de coalescen: trimetil-pentandiol-monoizobutirat

- agent de neutralizare: 2- amino-2-metil-1-propanol

La formarea i ntrirea filmului de NC,concur trei mecanisme: - autoreticulareapolimerului acrilic; - evaporarea apei i coalescenai - esterificarea ntre grupele funcionale alepolimerului i inelul oxiranic al epoxisilanului careacopersolul de SiO2.

Cantitatea de agent de coalescenutilizateste calculat pentru formarea filmului la 0oC ireprezint3% din masa polimerului uscat [5].

Amina a fost utilizat pentru neutralizareacomplet a formulrilor (pH=8-10) i pentru aasigura stabilitatea dispersiei; cantitatea de aditiv afost calculat, considernd indicele de aciditate alpolimerului (AN, mg KOH/g)

mamina=Maminax AN x mrin/56100

unde Maminaeste masa molara aminei; mrinestemasa polimerului [6].

characteristics of hard inorganic phase likehardness, the abrasion resistance, thermicstability, and chemical resistance. Usually can notmeet these antagonistic properties together neitherin conventional water based paints without fillersnor in water based coatings with micronised fillers.In this paper has been prepared water based

organo-inorganic coatings, having nanocompositestructure and improved mechanical and electricalproperties (compared with the traditional organicwater based coatings).

2. Experimental part

2.1. Preparation of nanocomposite dispersion(formulations 1-5)

Transparent laquer samples ofnanocomposite coating (NC) have been preparedto investigate and compare the properties of NCversus conventional acrylic coatings.

All samples (formulations) have beenprepared using:

- selfcroslinking acrylic copolymer in anionicdispersion, containing COOH functional groupsand having a core shell morphology [4] ;

- nanofiller : colloidal silica having the sizebetween 7-25 nm and surface modified withepoxysilan RSi(OCH3)3 (where R=3-Glycidoxypropyl) [4] ;

- coalescent agent : trimethyl-pentanediole-monoisobutyrate

- neutralisation agent : 2- amino-2-methyl-1-propanol

At the forming and hardening of NC filmcompete three mechanisms: one is selfcroslinkingof the acrylic polymer, second is water evaporationand coalescence and the last is the esterificationbetween functional groups of the polymer andoxiranic ring of the epoxisilan which cover the SiO2sol.

The quantity of coalescent used iscalculated for 0oC film formation temperature andrepresent 3% from total mass of dried polymer [5].

The amine additive was used for thecomplete neutralisation of the laquer formulation(pH=8-10) and for the ensure of the dispersionstability; the quantity of aditive was calculatedfrom acid number (AN, mg KOH/g) of polymer:

mamine=Maminex AN x mresin/56100

where Mamineis molar mass of amine; mresin is massof polymer [6].


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Probele au fost preparate cu diferiteprocente de sol de silice raportate la masa depolimer solid: 0% (Formularea 1), 10% (Formularea2), 20% (Formularea 3), 25 %( Formularea 4) i30%( Formularea 5).

Procentul maxim de nano silice utilizatpentru formularea de NC este dat de cantitatea

limit care pstreaz nemodificate proprietileoptice (luciu i transparen) fa de formulareafrnanofiler. La procente de silice sol mai mari de30%, transparena se modific.

Concentraia volumic de pigment (PVC) aformulrilor testate (dispersie apoas de NC) afost ntre 5 i 10% i s-a calculat dupformula:

PVC =100 x (VP+VF)/ (VP+VF+V rinsolid)[%]; [7,8]

unde VP = volumul de pigment , VF = volumulde filer, V rin solid = volum de polimer uscat +volumul de agent de coalescen(frCOV).

Acoperirile NC investigate au fost aplicateprin pulverizare pe metal, sticl sau polietilen.Filmul uscat cu grosime de 50-90 m, a fostreticulat la temperatura camerei (TC) timp de 24ore i respectiv 7 zile.

3. Rezultate i discuii

3.1. Caracterizarea morfologici topografica nanocompozituluiFormulrile 1-5 ale nanocompozitului

reticulat au fost caracterizate prin microscopieelectronic de baleiaj(SEM) i analiztermogravimetric(TG).

Analiza SEM a filmului monostrat imultistrat.

Topografia, morfologia, analiza elementelori distribuia acestora n microstructur au fostinvestigate utiliznd microscopul electronic debaleiaj Quanta Inspect F prevzut cu tun deelectroni cu emisie n cmp (FEG), spectrometrulde raze X dispersiv n energie (EDAX) cu rezoluie133 eV la MnK.

Imaginile suprafeelor de film au fostobinute prin trei metode de investigare: n regim depresiune joascu detector de cmp larg (LFD), nregim de presiune ridicat i regim de tensiuneaccelerat30kV cu detector de electroni secundari(ETD) i cu detector de electroni retromprtiai(BSED)

Topografia filmului monostrat (90 microni) imultistrat (300 microni), demonstreaz structuraheterogen a NC i distribuia omogen aparticulelor anorganice (culoare alb) n matriceaorganic (fig.1, 2, 4. ). Morfologia NC prezintreeaua anorganic ntreptruns cu matriceaorganic, fr separare de faze i textura NC din

filmul multistrat (fig. 3 - 7) evaluate n seciuneafilmului.

The samples were prepared with differentpercent of silica sol reported to solid polymer: 0%(Formulation 1), 10% (Formulation 2), 20%(Formulation 3), 25 %( Formulation 4) and 30%(Formulation 5).

The maximum quantity of nano colloidalsilica used for formulation of NC, was chose in

order to maintain the optical aspect (gloss andtransparency) similar with formulation withoutnanofiller. A procent of nanosilica over 30 %affected transparency of the NC film.

The pigment volume concentration (PVC)of tested formulations (aqueous nanocompositedispersions) was between 5 and 10% and followsthe formula:

PVC =100 x (VP+VF)/ (VP+VF+V Solid resin)[%]; [7,8]

where VP = pigment volume, VF=filler volume, VSolid resin= dried polymer (volume) + coalescent(VOC free) volume.

The investigated nanocomposite coatingswere applied by spraying on metal, glass orpolyethylene. Dried films with 50-90 m thicknesswere obtained at room temperature after 24 hoursor 7 days.

3. Results and discussion

3.1. Nanocomposite characterisationNanocomposite formulations 1 5 have

been characterised by scanning electronmicroscopy (SEM) and thermogravimetric analysis.

Scanning electron microscopy (SEM)analysis for monolayer and multilayer films

The topography, morphology, elementalcomposition of NC as well as distribution ofelements in the microstructure were investigatedusing Quanta Inspect F scaning electronmicroscop with FEG (field emission gun), and X-Ray Energy Dispersive Spectroscopy (EDAX) with133 eV resolution at MnK.

The micrographs of the film surface wereobtained in low-pressure regime with large filmdetector (LFD) and in high-pressure regime at anaccelerating voltage 30 kV by secondary electrondetector (ETD) and backscattered electrondetector (BSED).

The topography of top coat of dried film hasbeen evaluate for monolayer and multilayer (300microns) films which show the heterogeneousparticles structure and homogenous distribution ofinorganic (white spots) and organic matrix (Fig.1,2, 4. ) The morphology of NC reveals theinterpenetration of inorganic skeleton throughpolymer matrix without phase separation and thetexture of this nanocomposite are different

depending on drying condition.


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Fig.1 - Imagine SEM i spectru de energie dispersiv de raze X (EDAX) a suprafeei de film monostrat pentru formularea 1 (0%nanosilice) utiliznd ETD / SEM image and energy dispersive X-ray spectrum (EDAX) of the monolayer film surface forformulation 1 (0% nanosilica) using EDT.

Fig.2 - Imagine SEM (50000x) i EDAX a suprafeei filmului monostrat, formularea 5 ( LFD i ETD) / SEM image (50000x) and EDAX ofmonolayer film surface for formulation 5( LFD and ETD).

Fig.3 - Imagine SEM (800x) a seciunii n filmul multistrat,formularea 5 (30% nano silice) utiliznd ETD / SEMimage (800x) of a section in a multilayer film withformulation 5 (30%nano silica) using ETD.

Fig.4 - ImagineSEM (6000 x) a zonei E, a suprafeei filmuluimultistrat, formularea 5 utiliznd BSED /SEM image(6000 x) of E zone from multilayer surface offormulation 5 using BSED.


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Filmul multistrat, prezintstructurde reeai a fost obinut din patru straturi reticulate ncondiii diferite: primul strat a fost reticulat 7 zile laTC (zona E), stratul secundar a fost reticulat la30C/24 h i este reprezentat de seciunile D i C,stratul trei, localizat n zona B a fost reticulat la40/12 , iar stratul 4 , situat n zona A a fost

reticulat la 45 C/24 h.Analiza EDAX pentru formularea 5,

prezentatn figura 2, confirmcompoziia C, O, Sii distribuia omogena acestor elemente.

Analiza termogravimetricAnaliza TG a formulrilor 1 (frsilice) i 5

(cu 30% silice) este prezentatn figura 8.Se observ stabilitatea termic relativ

ridicat a filmelor ; descompunerea termic afilmelor n dou trepte, n intervalul 210-4800C, nueste influenatde coninutul n nanosilice (fig.8).

4. Proprietile mecanice i electrice alenanocompozitului

Incercrile pentru rezistene mecanice ielectrice au fost realizate pe film NC monostrat(formularea 5) cu morfologia artatn figura 2 iarrezultatele determinrilor au fost comparate cucele ale formulrilor 1-4.

In a multilayer film section (Fig 3-7), thereare four layers: first layer was dried at roomtemperature (RT)/7 days (site E), second layer isrepresented by D and C sites (30C/24 h), the thirdlayer represented by B site (40C/12 h) and thelast layer by A site (45 C/24 h).Each layer possesthe network structure.

Fig.5 - Imagine SEM (6000 x) pentru primul strat (seciune E),formulare 5 /SEM image (6000 x) for the first layer(section E).

Fig.6-Imagine SEM (6000 x) pentru stratul doi (seciune C si D) / SEM images (6000 x) for the second layer (section C and D).

Fig. 7 - ImagineSEM pentru stratul trei ( Sectiune B, 6000 x) i stratul 4 / (Seciune A, 12000 x) /SEM image for third layer ( Section B,6000 x ) and four layer (Section A, 12000 x).


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Fig. 8 - Analiza TG pentru formulrile 1i 5 / TG analysis offormulation 1 and 5.

Thermogravimetric analysisThe thermal analysis of Formulation 1 (pure

polymer) and Formulation 5 (30% silica content) ispresented in Fig.8. It was observed relative highthermal stability of the films: thermaldecomposition in two steps between210 4800Cwas not influenced by the nanosilica contain.

4. Mechanical and electrical properties ofnanocomposite (Formulations 1-5)

The tests for mechanical and electricalresistance was made on NC monolayer film(Formulation 5, with morphology showed in Fig. 5in comparison with others Formulations 1-4).

A. Evaluarea duritiis-a fcutprin doumetode:Prima metod, ISO 1518, demonstreaz

rezistena la zgriere prin penetrarea unui acncrcat cu sarcini diferite: 100 g, 200 g. 300 g, 400g, 500 g. In timpul testrii acul a fost ncrcatprogresiv cu discuri cu greuti de 100 g iardeplasarea acestuia pe suprafaa filmului s-a fcutcu vitezconstantde 40 mm/s. Formularea 1 (lacacrilic pur) este zgriatla ncrcarea cu 100 g. Laformularea 2 acul a penetrat pelicula la 200 g iar laformularea 5 (cu concentraie maxim de silice)pelicula a fost zgriatla 400 g.

A doua norm de evaluare (EN ISO 1552),utilizeaz pendulul Persoz iar exprimarea duritiise face prin cuantificarea (n sec) a oscilaiilorpendulului (tabelul 1).

A. The hardness investigation of the preparedcompositions was carried out using twomethods.

First method, ISO 1518, was used to assessthe resistance of a dry film, to penetration byscratching with a weighted needle with differentloads 100 g, 200 g. 300 g, 400 g, 500 g. During thetests the needle was loaded with discs (with stepdevice increase mass by 100 g from 100 g to 500g) and moved with constant speed (40mm/s). Atthe Formulation 1, which is pure acrylic lacquer,the needle penetrates at 100 g load. The scratchwas observed at 200 g on the Formulation 2 and atthe maximum concentration of nanofiller, the layerwas penetrated at 400 g.

The second method, EN ISO 1552, involvesthe Persoz pendulum; assess the hardness by

Tabelul 1

Evaluarea duritii pentru formularea 5 prin metoda pendulului / Hardness values determined by pendulum methodCondiii de uscareDrying conditions

Valori ale duritii [sec], determinate prin metoda pendululuiHardness values [sec] determined by pendulum method

FormulareaFormulation

1


2


3


4


524h la/ atTC 35 58 78 82 85

7 zile la /days atTC 39 65 83 90 117

Conform ambelor metode folosite, testele deduritate demonstreaz c NC avnd formularea 5posed duritate dubl fa de formularea 1 (frnanofileri).

B. Testele de rezistenla abraziunedemonstreazclacul acrilic pierde 80% din masa iniialdup50 de cicluri de polizare cu rola abrazivnr. CS17 n timp ce formulrile nanocompozitice suntmai rezistente (formularea 2 pierde 60% dinmas, formularea 3 pierde 55% iar formularea 4pierde 45%); cantitatea minim de masndeprtat prin abraziune este de 35% icorespunde formulrii cu coninut de 30% nanosilice. Testele s-au efectuat pe filme reticulate 7zile la TC, utiliznd un aparat de abraziunerecomandat n norma ASTM D 4060.

C. Rezistena la fisurare a fost evaluat dupstandardul ASTM D 522, utiliznd pentrundoirea filmului de lac, mandrina cu diametrul

measuring oscillation amplitude of a pendulum.The evaluation of hardness was made after

drying at room temperature, 24 hours or 7 days(Table 1)

The nanocomposite having Formulation 5has double hardness value on both test methodsin comparison with Formulation 1 (withoutnanofiller).B. The results of abrasion resistance evaluation

show that traditional acrylic lacquer loss 80 %mass during the abrasion with abrasive rolenr.CS 17 after 50 cycles and thenanocomposite coatings with silica sol aremore resistant (Formulation 2 lost 60% mass,Formulation 3 lost 55% and formulation 4 lost45%) ; the minimum mass lost is 35%corresponds to 30% silica sol content. The test

was made using the test abraser followingnorm ASTM D 4060 and samples was dried


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de 1 mm.Toate formulrile testate au avutgrosime film umed 90-100 microni i au fostuscate 7 zile la TC. Dup ndoire toateeantioanele au fost fr fisurare ceea cedovedete c materialul anorganic nu amodificat flexibilitatea filmului.

D. Testele de rezistena la ambutisare (teste deelasticitate)au artat c la deformaia de 7-7,5mm toate formulrile sunt stabile.Pentrurealizarea acestor teste s-au utilizat filme deaceeai grosime, iar suportul metalic acoperitcu aceste filme a fost deformat cu un profilhemisferic la presiunea de 280 N/mm2 i vitezade 0,2 m/s.

E. Testul la voltaj nalt a fost realizat pentruformulrile 1 i 5 pe filme cu grosimi cuprinsentre 30 i 40 microni. Pentru formularea 1(frsilice) descrcarea de sarcin s-a realizat la

2000 voli iar pentru filmul de nanocompozit la4000 voli. Imbuntirea rigiditii dielectrice seexplic prin reducerea migrrii de sarcin idescreterea porozitii n masananocompozitului [9].

F. Rezistena la blocking. n general, pentruacoperiri peliculogene cu PVC sczut trebuiegsit un compromis ntre elasticitate i duritateaa nct s se obin o bun rezisten lablocking (lipirea pieselor vopsite i uscate lapresare) i o bun elasticitate care s asigurestabilitate la intemperii [8]. Toate formulrile

testate au avut elasticitate i flexibilitatecomparabil iar rezistena la blocking a crescutproporional cu coninutul de silice, evaluareprezentatn tabelul 2. Testul a fost realizat cu opres de 400 g/ cm 2/24 h iar depreciereasuprafeelor a fost evaluatvizual i notatde la1 la 5 (0 = excelent, 5= cel mai depreciat ) Aacum se vede n tabelul 2, NC cu 30% silice arerezistena la blocking mbuntit fade restulformulrilor, chiar i la temperaturridicat.

before testing 7 days at room temperature.

C. The cracking resistance was evaluating afterASTM D522 using the smallest conical mandrelwith 1 mm diameter for bend the panelscovered with coatings. All the formulations wereapplied at thickness 90-100 mm wet and dried

7 days at room temperature. After the bending,all formulations exhibit the aspect withoutcracking.

D. The cupping resistance (elasticity) ISO 1520showed that all the Formulations had the depthof deformation at 7-7.5 mm without cracking.For these tests, all paints had the samethickness; the coated panels were stressed withthe hemispherical indenter, pressure 280N/mm2and speed 0.2 m/s.

E. The high voltage testwas made for Formulation1 and Formulation 5 with 30-40 micronsthickness. The value of spark discharged was2000 volts for Formulation without silica and4000 volts for nanocomposite film. Theexplanation of improvement of dielectric rigidityis the new structure with reduced chargemigration and decreased porosity in bulk NC[9].

F. The blocking resistance. For water based acryliccoatings with low PVC, a compromise betweenhardness and elasticity must to be found, whichyields to good blocking resistance and sufficientelasticity to ensure weathering stability [8]. Alltested formulations, had the comparableelasticity and flexibility (cracking resistance) andthe blocking resistance increased proportionallywith the nanosilica content as in Table 2.Theblocking test was made with press 400 g/cm2/24h and the surface damaged and marked wasvisually evaluated: 0=excellent ; 5=worst. As wecan see, in Table 2, the NC with 30% silica solimproved the blocking resistance even atelevated temperature.

Tabelul 2

Valoarea rezistenei la blocking pentru formulrile de acoperiri NCValues of blocking resistance for the tested NC coatings

Condiii de testareExperimental

conditions

Valori ale rezistenei la blocking / Values of blocking resistanceFormulareFormulation1

FormulareFormulation

2


3


4


524 h / TC 1 1 1 0.9 0.8524 h / 50 C 4.5 4 2.2 2 1.224 h / 100 C 5 4 2.5 2 1.27 zile/days/ TC 0.8 0.7 0.5 0.5 0.157 zile / days/ 50 C 5 4 2 1.8 17 zile /days /100C 5 3.9 2.8 1.5 0.3

3. ConcluziiO dispersie organo-anorganic de material

de acoperire a fost preparatntr-un sistem formatdin emulsie de polimer acrilic-nanosilice ca filer-aditivi.

3. Conclusion

A water based organo-inorganic dispersionas coating material has been prepared in the


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Rezultatele analizei SEM demonstreaz cacoperirea nanocompozitic are reea organicinterptruns cu scheletul anorganic, structuromogen, compact distribuie uniform aelementelor componente, pstrnd nemodificateproprietile optice (luciu i transparen).

Testele experimentale (duritate, rezistenla

abraziune, elasticitate, flexibilitate, rezisten lablocking, rigiditate dielectric) demonstreaz cproprietile mecanice i electrice ale filmelor suntcontrolate de prezena nano silicei iar distribuiauniform a silicei n matricea organic are un roldecisiv n mbuntirea calitii filmelor.

MulumiriAcest studiu a fost susinut din proiectele CNCSIS-UEFISCU PN II-idei cod ID_1043/2007 i ID_1364/2008

REFERENCES

1. xxx,European Union Directive 2004/42/EC & 1999/13/EC2. M.Georgescu, N.Saca, and G.Voicu, The behaviour of some

blended cements containing limestone filler exposed intoMgCl2 solution, Romanian Journal of Materials, 2010, 40(4)271.

3. S.Sepeur, N.Laryea, and S.Goedicke, Nanotechnology,Vicentz Network, Hannover, 2008, p.19, p.56-60.

4. P. Bell, Effect of nanofillers in adhesive and aestheticproperties of resin composites, NeoResins Bull, 2001, 1, 25

5. B.Muller, and U.Poth, Coatings Formulation, Vicentz,Hannover, 2006, p 61,p 170.

6. J.Leuninger, F.Tiarks, H.Wiese, and B.Schuler, Farbe&Lack,2004, 10, 30.

system acrylic polymer emulsion nano silica asfiller additives.

The results of SEM analysis reveal that thenanocomposite coating has an interpenetratednetwork organic and inorganic skeleton, withhomogenous structure, uniform distribution ofelements and compact structure and posses

unaltered optical properties (glass andtransparency).

Our experimental tests (hardness, scratchabrasion, blocking resistance, elasticity, flexibility,dielectrical rigidity) demonstrate that themechanical and electrical properties are controlledby the presence of nano silica and the uniformdistribution of inorganic particles in organic matrixhas a decisive role in improvement of film qualities.

AcknowledgmentsThis work was supported by CNCSIS-UEFISCU projectPN II-Idei code ID_1043/2007 and PN II-Idei code

ID_1364/2008

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7. H.Schmidt and R.Kasemann, Coatings for mechanical andchemical protection based on organic-inorganic sol-gelnanocomposites, New J.Chem.,1994,18,1117.

8. J.Livage, C.Sanchez, M.Henry and S.Doeuff, Design ofhybrid organic-inorganic materials synthesized via sol-gelchemistry, Solid State Ionics, 2002, 32-33, 633.

9. F. De Matteis, P. Prosposito, M. Casalboni, M. L. Grilli, E. DiBartolomeo and E. Traversa, Electrical Properties of Sol-GelProcessed hybrid Films, J. Sol-Gel Science andTechnology, 2003, 26, 1081.

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MANIFESTRI TIINIFICE / SCIENTIFIC EVENTS

The International Conference of Nanotechnology Research and Commercialisation(ICONT2011),

06 - 09 June, 2011, Sabah, Malaysia

The main objective of the conference is to provide a communication stage for Malaysian scientistsworking in the field of nanoscience and nanotechnology with their counterparts from Asian and rest of theworld. The conference is expected to create effective networks among the research institutes universities,institutions and companies and to promote the inter-countries and interdisciplinary collaborations and hence

will greatly contribute to the rapid progress in the nanotechnology research.

The Scope of ICONT 2011

Nanomaterials: nanoparticles, nanowires, carbon nanotubes, functionalized polymers, etc. Nanodevices, Nanoelectronics and Nanophotonics Nanobiotechnology, Nanomedicine and Drug Delivery Systems Nanofabrication and Self-organization systems Nanotechnology Application including in Energy, Environment and Health Nanotechnology Standardisation Nanoparticles Toxicology, Health and Safety Societal and Environmental Impacts and other related topic including nano initiative and policy

Contact:http://icont2011.sirim.my/#

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materiale de acoperire organo-anorganice nanostructurate

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