Field of the Invention
This invention is related to a functional organic-inorganic hybrid nanocomposite structured with boron.
In everyday life, the goods that we are using are subjected to contamination because of environmental factors. In order to avoid this contamination, these are either cleaned by cleaning agents or certain additives are added to these goods during their production so as to keep them free of dirt. For keeping goods clean, photocatalytic materials and coatings are used. Titanium dioxide (TiO2
) and zinc oxide (ZnO) are photocatalytic materials that are used for this purpose in different applications. TiO2
is a photocatalytic material which exhibits high oxidation characteristics when activated under UV light. With this property, it breaks down the undesired organic dirt particles on the surface.
There are studies done in the state of the art applications which try to increase the photo-catalytic productivity of TiO2
and ZnO. In the state of the art applications, TiO2
, ZnO and similar different nanoparticles and combination of these nanoparticles are being used. However some of these, because of their photocatalytic effect, in time, are also breaking down the organic coatings they are embedded in. In the UV wavelength region under optical activation, the activity of these materials does not reach a maximum level. Under visible wavelength region, the activity shows a weaker performance. In the literature, we could not find a study using the sol-gel technique to integrate boron compounds together with TiO2
and Zn in order to get a nanocomposite material.
The Chinese patent document CN1736583-A
, one of the state of the art applications, discloses a nanooxide synthesis with boron. In this document, boron nanoparticle is placed into the crystal structure (doping). This document does not mention anything about a nanoparticle integrated with boron in a composite structure outside of the crystal structure.
The Japanese patent document JP2002210364-A
, one of the state of the art applications, discloses a form of ZnO film with good photocatalytic properties. It is mentioned that ZnO film contains 0.001-20% boron. The said document discloses forming a ZnO containing coating with the wet electrocoating technique. This is not a sol-gel technique.
The Japanese patent document JP9040872-A
, one of the state of the art applications, discloses a TiO2
containing composition with photocatalytic activity. There is disclosed an inorganic composition in the document but an organic host material is not mentioned. US7253226-B1
- silica sols made by combining at least one hydrolysable silane, at least one organofunctional silane, at least one boron oxide compound, and a liquid, or silica sols made by combining at least one hydrolysable silane, at least one organofunctional silane, at least one acid catalyst, and a liquid to provide an intermediate sol and combining at least one base catalyst with the intermediate sol;
- nanocomposites containing the silica sols and at least one of metal nanoparticle, metal-chalcogenide nanoparticle, metal-oxide nanoparticle, and metal-phosphate nanoparticle;
- and composites containing a polymer material and at least one of the silica sol and the nanocomposite.
In particular, US7253226-B1
discloses in example 27, the preparation of a mixed metal-oxide sol (SiO-TiO). A solution of TEOS and phenyltrimethoxysilane in methoxyethanol is prepared. It is stirred at RT/2 hrs after addition of titanium isopropoxide and boric acid. and then further stirred at RT/overnight and 120°C/3 hrs after addition of DI water. The resulting clear solution is vacuum dried and heat treated at 190°C in an oven to give colorless residues which are readily soluble in methoxyethanol to give a clear solution.
After combining and mixing suitable amounts of the polymer and the silica sols and/or the nanocomposites containing at least one of the metal nanoparticles, metal-chalcogenide nanoparticles, metal phosphate nanoparticles, and metal-oxide nanoparticles, the mixture is then cured, molded, extruded, formed, or subjected to suitable polymer processing to form a polymer composite having the silica sols and/or the nanocomposites substantially uniformly dispersed therein.
describes a self-cleaning, oxidative drying paint, showing photo-catalytic effect and being water-based, and the production method thereof.
Said method basically comprises the following steps:
- Partial hydrolysis of silanes (possibly dissolved in solvents) which takes place within at least 24 hours at room temperature; the pH value in the medium is preferably adjusted as maximum 2.0 for the reaction. The silanes used can be selected among silanes carrying hydrolyzed group, methyl triethoxy silane, methyl methoxy silane, tetra methyl ortho silicate, tetraethyl silicate, 3-glycidyloxypropyl trimethoxy silane etc. or non-hydrolyzed silanes, silanes carrying vinyl, metacryloyl, phenyl, fluorine, amino, mercapto etc. group or a mixture thereof in certain proportionsAcid catalysts used are preferably strong acids. The proportion of acid catalysts to silanes is maximum 0.5% by weight.
- Modifying the surface of nano-sized metal-oxide particles with the obtained hydrolysate: the hydrolyzed silanes are added to the nano-sized anatase type calcined titanium dioxide. The proportion of hydrolysate used to titanium dioxide is between 25-100% by weight. The size of nano-particles can be between 5-25 nm. The process takes place at minimum 100°C.
- Dispersing of nano-sized metal-oxides with modified surfaces within water-based and oxidative drying resins.
- Mixing the obtained product with certain paint formulations known in the art.
relates to the preparation and making of nano composites comprising TiO2 and ZnO dispersed in functional acrylic/metacrylic structure. TiO2 and ZnO are hydrolyzed as they are dispersed in the polymer.Then, they react with the monomers and the reaction initiators, to form a matrix.
Purposes of the Invention
The invention aims notably to reach at least one of the following purposes.
The purpose of the invention is to develop a new photocatalytic nanocomposite structured with boron with enhanced photocatalytic activities in the UV and visible regions of the spectrum.
Another purpose of the invention is to develop a photocatalytic nanocomposite structured with boron with NOx, COx and SOx breakdown properties converting them into harmless compounds.
Another purpose of the invention is to develop a photocatalytic nanocomposite structured with boron which provides antimicrobial activity.
A further purpose of the invention is to develop a photocatalytic nanocomposite structured with boron with self cleaning and easy cleaning properties.
Another purpose of the invention is to develop a photocatalytic nanocomposite structured with boron containing silicon and/or silane based resin with high scratch and dirt pick-up resistance.
Another purpose of the invention is to develop a photocatalytic nanocomposite structured with boron which makes it possible to obtain thin film coating (e.g. 20-1000nm thickness). An additional purpose of the invention is to develop a photocatalytic nanocomposite structured with boron with high water resistance.
A further purpose of the invention is to develop a photocatalytic nanocomposite structured with boron with antifog properties when applied on glassy surfaces.
Another purpose of the invention is to develop a cheap photocatalytic nanocomposite structured with boron with high durability and large scale production possibility.
Another purpose of the invention is to develop a photocatalytic nanocomposite structured with boron with enhanced photocatalytic properties, but on the contrary with less self-breakdown due to its higher durability.
Another purpose of the invention is to develop a photocatalytic nanocomposite structured with boron with enhanced photocatalytic properties and which is in the form of colloidal liquid suspension.
Another purpose of the invention is to develop a photocatalytic nanocomposite structured with boron with enhanced photocatalytic properties and which is in the form of a solid that can be dispersed into a liquid to form a colloidal liquid suspension.
Yet another purpose of the invention is to use a photocatalytic nanocomposite structured with boron with enhanced photocatalytic properties, as active component of improved paint, concrete, mortar, ceramic or coating compositions or as glass-like material.
Brief description of the invention
The invention fulfils at least one of these purposes, among others.
In this respect, the invention concerns a boron integrated photocatalytic nanocomposite with an enhanced optical recovery in the UV and visible region, according to claim 1.
This sol-gel nanocomposite is characterized:
- by a photocatalytic activity given by a test T1 measuring the optical cleaning (OC) of a standard surface coated with the sol-gel nanocomposite, after exposure to different UV λ, such as: for λ ≤ 380nm, OC ≥ 30%, preferably OC ≥ 35%, and more preferably 70% ≥ OC ≥ 40%;
- and/or by a surface morphology obtained after dip coating onto a standard surface according to standard protocol P1, and observed by Atomic Force Microscopy (AFM) according to a protocol P2, such as the coating has at least one of the following features (s1), (s2), (s3):
(s1) the surface comprises a mean number of discrete peaks per µm2 between 5-65, preferably 15-55, and, more preferably 25-40,
(s2) the height of these peaks being between 5 and 100 nm, preferably 10 and 60 nm, and, more preferably 15 and 50 nm,
(s3) and the base diameter of these peaks being between 30 and 500 nm, preferably 50 and 350 nm, and, more preferably 70 and 250 nm.
The photocatalytic nanocomposite according to the invention is structured with boron and has a high water resistance due to its silica coating.
In another aspect, the invention relates to the use of the sol-gel nanocomposite according to the invention in a paint composition.
In another aspect. the invention relates to the use of the sol-gel nanocomposite according to the invention in a concrete composition.
In another aspect, the invention relates to the use of the sol-gel nanocomposite according to the invention in a mortar composition.
In another aspect, the invention relates to the use of the sol-gel nanocomposite according to the invention in a ceramic composition (e.g. for the manufacture of tiles).
In another aspect, the invention relates to the use of the sol-gel nanocomposite according to the invention in a coating composition for polymer films or glass or ceramic..
Any singular in this text shall correspond to a plural and reciprocally. "Me
" means methyl
means ethyl According to the present invention, "Hydrophilic character
" means for instance that the contact angle measured is less than 90°, highly hydrophilic surfaces are having contact angle between 0° and 30°.
According to the present invention, "Hydrophobic character"
means for instance that the contact angle measured is equal to or higher than 90°.
Test T1: Optical Recovery Measurements:
Methylene blue is used for contaminating surfaces and results of recovery observed after exposure to UV radiation.
|Xenon Light Source:
||Spectral Products - CM110 1/8m|
|Power meter: (Model 1835-C)
||Newport - Multifunctional Optical Meter|
|Detector & Calibration Module:
||Newport - 818-UV|
Labview Program used for controlling monochromator to set wavelength and gather data from power meter.
||% 0.04 solution|
- Activate xenon light source, wait until it heats up and reaches steady state.
- Using Monochoromator via Labview, Scan the corresponding microampere (µA) for 300nm-800nm wavelength interval. (No samples attached to detector) (to determine energy for each wavelength and use it to calculate activation times for samples)
- Using glass cutter, Cut samples (coated glasses) in to 1.7cmx1.7cm squares.
- Attach a non-coated glass to detector and measure µA value for visible spectra (390nm-750nm). (to be a future reference for transparency comparison of samples)
- The following part is repeated for each sample:
∘ Attach sample to detector, scan visible spectra (390nm-750nm) (This will be the "clean" data);
∘ Take off the sample, apply Methylene blue on it (approximately 3 milliliters is enough to cover surface.);
∘ Wait for surface to be contaminated. (5minutes)(Do not expose sample to light during contamination.);
∘ Get the excessive amount of Methylene blue from surface;
∘ Attach sample back to detector;
∘ Scan sample visible spectra (390nm-750nm) (This will be the "contaminated" data);
∘ Using MATLAB code, calculate needed activation time for desired activation length by using initial power measurement;
∘ Activate the surface in UV (i.e. 300nm);
∘ Scan sample visible spectra (390nm-750nm)(This will be the "recovered" data);
∘ By using "clean", "contaminated" and "recovered" data calculate % cleaning.
- Take off samples. shut down system.
Dip Coating Application
||KSV DX 2S-500|
At room temperature, the substrate. which is a glass microscope slide, is immersed into the coating solution consisting in the boron integrated photocatalytic nanocomposite according to the invention (for instance prepared as described in example 1, 2). The coating solution is contained in a circular container chosen such as the length of the slide is less or equal to one-third of the diameter of the container. The speed of immersion (dipping) is 10-100 nm/min. As soon as the slide is totally immersed into the coating solution, said slide is pulled out of the container with the same speed, without waiting in immersed position. When the lamella is out of the container, it is kept in vertical position for 10 minutes to have necessary drainage and evaporation.
AFM measurements are conducted as both contact and non-contact mode due to fact that AFM measurement results differ regarding the hardness of the material. Films formed differ in hardness according to their substances.
For contact mode: Contact mode tip ContactAl-6 which has resonant frequency of 13 kHz and force constant 02.N/m used for scanning.
For non-contact mode: Non-contact mode tip TOP300A1-6 which has resonant frequency of 300 kHz and force constant of 0.3N/m used for scanning.
- AFM is set to its initial position, tip mounted on it.
- Laser of the AFM set on the tip to be able to make the measurement.
- Tip is approached to sample
- Only for non-contact mode: Before getting close to surface frequency is set to appropriate value to obtain as sharp images as possible.
- Data is gathered in both directions to confirm structure is observed well enough.
- Data's processed in XEI to get 3D images.
Detailed Explanation of the Invention
a TiO2/B nanocomposite composition according to the invention.
a control composition with no nanoparticle.
The boron integrated photocatalytic nanocomposite
There are at least two ways to define the new nanocomposite according to the invention: the product-by-process way and the structural way.
The compounds dissolved in the alcohol during the hydrolysis and condensation step -A-are advantageously one or more of the following:
( i) silanes: alkylalkoxysilane, fluoroalkoxysilane, organo-functional silane, aminofunctional silane, preferably tetraalkoxysilanes, and more preferably tetramethoxysilanes, tetraethoxysilanes,
( ii) and/or semiconducting metal containing metalalkoxyoxides or metalloidalkoxides, (e.g. boron, titanium, zirconium) preferably trialkylborates, and more preferably trimethylborates, triethylborates.
The alcohol is preferably R-OH, wherein R corresponds to C1-C10 alkyle, preferably C1-C3 alkyle, and R-OH being more preferably EtOH.
The compounds dissolved in alcohol are advantageously Si(OMe)4
Preferably, the acid added during the hydrolysis and condensation step -A- is hydrochloric acid or boric acid, or hydrochloric acid and boric acid.
In fact, the pH is less or equal to 3, preferably 2. So, the acid or the combination of acids is chosen quantitatively and qualitatively therefore.
As an example of the compounds and the concentrations used in step -A-, there are for 2 M of Si(OEt)4
, for instance 0.5-3.5M, preferably 1-3M, more preferably 2M of Si(OMe)4
, 0.5-3.5M, preferably 1-3M, more preferably 2M of (Me)3
, 0.25-2M, preferably 0.5-1.5M, more preferably 1M of alcohol (e.g. EtOH), 0.001-0.5M, preferably 0.01-0.1M, more preferably 0.04M of a strong acid (e.g. HCl), and 0.01-1.5 M, preferably 0.1-1M, more preferably 0.3M of H3
Preferably, the heating during the hydrolysis and condensation step -A- is at a temperature comprised between 50 and 100°C. preferably between 60 and 90°C or between 75 and 85°C.
It is advisable according to the invention that the hydrolysis with water and dissolving agent, during the hydrolysis and condensation step -A-, endures 4 to 8 hours.
In a preferred embodiment, during the metal loading step -B-:
- 20-80 nm nanoparticles of boron oxide are added to the hydrolysis mixture,
- and the 2-50 nm anatase type TiO2are added and possibly at least another metal-oxide chosen within the group comprising zinc oxide, aluminium oxide, thallium oxide, zirconium oxide and mixes thereof. can be added;
- and a heating under agitation for 1h-5h at a maximum temperature of 100°C, is done.
In this variant with nanosized ZnO, a nanocomposite material TiO2
-boron-ZnO is obtained.
According to an advantageous embodiment, silica, preferably fumed silica, is added to the organoboron and the nanosized metal-oxides, during the metal loading step -B-.
The nanosized TiO2
added during the metal loading step -B- is of an anatase type TiO2
of a size comprised between 2 and 50 nm.
According to a remarkable feature of the invention, the heating during agitation of the metal loading step -B- occurs for 1h-5h, at a maximum temperature of 100°C, preferably of 90°C or of 85°C.
The resin (b) is preferably silane, siloxane or silane coupling agent modified resin. It could be for example the commercial product Ultrabond P287® manufactured and sold by the Chemical village corporation. It is an aqueous emulsion copolymer of styrene and acrylic ester. The polymer has been silane modified to impart very high water resistance and rubbing fastness. This polymer has been specially designed for manufacturing paint and coating.
Other examples of suitable resins (b) are Setaqua® 6801, Setalux® 2117 from Nuplex® resins
According to a preferred feature of the invention, the resin (b) is a thermosetting resin.
Preferably, the condensation (thermosetting) of the resin (b) during the resin addition step - C- occurs at a maximum temperature of 80°C, preferably of 60°C or of 40°C.
The condensation (thermosetting) time of the resin is 0.5-3 hours, more preferably 1 hour +/- 0.1, under agitation.
Improvingly, the resin is bonded to the nanocomposite matrix with covalent bonds. Actually, at least a part of the resin is linked to the shell of the clusters of particles (a).
At least another part of the resin is dispersed or dissolved in the liquid continuous phase (c) (if present) of the boron integrated nanocomposite.
In a preferred embodiment, the boron integrated nanocomposite comprises the particles (a), the resin (b) and the liquid continuous phase (c).
Thanks to its specific structure wherein nanoparticles (a.1) TiO2-, boron oxidenanoparticles (a.2.1), and possibly (nano)particles (a.2.2) -e.g. SiO2
-, are embedded in a three-dimensional network (-a-)(-b-), the nanocomposite of the invention has notably the following functionalities: photocatalysis, biocid, high water-resistance (hydrophobia), anti-stain, easy-clean, anti-graffiti, anti-fog.
Thus, the boron integrated nanocomposite according to the invention, can be used as coating or film which can be bonded to various substrates, providing to these latter the above-mentioned functionalities and moreover, having high and long stability/durability, high scratch, dirty pick-up and rub resistance.
The metaloxide of the nanoparticles (a.1) is titanium dioxide.
The boron oxide can be for instance B2
The metalloid of the metalloidoxides in the preferable (nano)particles (a.2.2) is preferably Si.
The metals of the metalalkoxides of the lattice (a.3) are selected from: Ti, Tl, Zn, Zr, Al and mixes thereof.
The metalloids of the metalloidalkoxides of the lattice (a.3) are selected from: Si, B, Sb and mixes thereof.
The alcohols of the lattice (a.3) are alcohols of formula R-OH, wherein R corresponds e.g. to C1-C10 alkyle, preferably C1-C3 alkyle, and R-OH being more preferably EtOH.
The resin (c) can be linked to the clusters (a) of particles notably via -O- bridges and/or -C-bonds. It means that the reactions which give rise to these bonds are respectively hydrolysis/condensation and addition on double bonds. for instance.
The invention has a unique advantageous morphological structure owing to the synergetic effect of boron and titanium dioxide.
This process according to the invention, for the production of a boron integrated photocatalytic sol-gel nanocomposite, can comprise all or part of the features defined above in respect to the nanocomposite.
The inventive photocatalytic nanocomposite structured with boron enables air polluting gases such as NOx, COx and SOx to be converted into harmless compounds. Also, the said material has antibacterial, antimicrobial, self cleaning and easy-clean properties together with low dirt pickup and low scratch properties due to silicon, boron and silica resin. The inventive nano material obtained with solgel method can be used as thick coatings with other materials or can be used on its own yielding film thicknesses less than 1 micron. Having been coated with silica, the product has good water repellence properties and has antifog properties when applied on glassy surfaces. The photocatalytic nanocomposite structured with boron is more inexpensive compared to use of metal-oxides produced by doping method, and it can be produced in large quantities and is more durable.
Nano materials containing no boron compounds have limited activation under UV light. Some of these nanoparticles, in time, are break down the coating in which they are embedded. During production of the said nano material, nanometaloxide material integrated with boron is covalently bonded in the composite structure and this increases the abrasion resistance of the coating preventing breakdown of material and loss of mass in time.
Metal atoms are distributed in a disordered manner but homogeneously in the photocatalytic nanocomposite structured with boron whereby enhancing the photocatalytic effect.
The inventive photocatalytic nanocomposite structured with boron has good application in the health sector where high hygienic conditions are required. Owing to its easy-clean, self cleaning, antimicrobial and antibacterial properties, the invention has wide applications in hospitals, public use areas, food processing sites, protection of important products, environment, security etc. The inventive nanocomposite can be applied as a coating in the form of a thin film on its own or can be applied within other materials. Besides, it can be used in glass production due to its antifog properties. Photocatalytic nanocomposite structured with boron, also converts air polluting gases such as SOx, NOx and COx to harmless compounds when applied on exterior and interior surfaces in the construction sector, interior and exterior painting and in all kinds of coatings. Also, it can be used in places like closed parking lots where sunlight is not available, under the light emitted from the light sources.
The nanocomposite according to the invention can be used together with different materials in the form of thick films or of thick films of minimum 10µm, preferably of minimum 20µm, and, more preferably of 50 to 10.000 µm.
Said nanocomposite can also be used as a sole film of maximum 1 micron or of thickness less than 10 µm, preferably less than 5µm.
Film making or coating with the nanocomposite according to the invention, presupposes that said Boron integrated nanocomposite is preferably liquid (abc) and is applied on a substrate through conventional methods brushing, spraying, spin coating, rolling, wiping among others.
The film-making or -coating process can include an activation of the hardening (curing) of the film or the coating, for instance a thermal activation e.g. at a temperature greater or equal to 20°C, preferably comprised between 30-60°C.
Preferably, said nanocomposite is used in the health, food, environment and safety sectors because of its easy clean, self cleaning, antimicrobial and antibacterial properties.
In an application, among others, of the invention, said nanocomposite is used in the glass production because of its antifog properties.
Coating compositions containing the nanocomposite according to the invention can be applied on different substrates, for instance:
- ceramics (tiles)
- concrete, mortar
These coatings or films on glass, ceramic, concrete or mortar substrates of buildings have notably anti-graffiti properties.
When applied onto metallic substrates (steel, aluminium), these coatings or films provide anti-stain and easy-clean properties. These latter are particularly interesting for metals used for the manufacture of household appliances of elevators, of exterior walls (frontages) of buildings.
The sol-gel nanocomposite according to the invention can also be a paint or a (transparent) varnish.
In another application, said nanocomposite is used in the construction and painting sectors in the form of coating because of their cleaning effect on NOx, SOx and COx.
This nanocomposite can be used as exterior or interior photocatalytic wall paint by adding extenders such as calcites and resins and siloxanes if needed.In another application, said nanocomposite is used in closed spaces with no sunlight where the photocatalytic effect could be obtained by different light sources.
Example 1- Preparation of a boron integrated nanocomposite according to the invention:
Mixture A: 2 moles of Dynasylan A, C8
Si (tetraethoxysilane, CAS no 78-10-4
), Dynasylan M, C4
Si (tetramethoxysilane, CAS no 681-84-5
) and Kemira grade trimethylborate C3
(CAS no 121-43-7
), 99.8% purity mixture is loaded into glass reaction vessel under mixing. After, homogenization of the mixture 1 mole of ethyl alcohol is added to the vessel). Following that, 0.04 moles of HCl in water is added to the reactor together with 0.3 moles of boric acid in ethyl alcohol. 99.5%, C2
O, CAS no 64-17-5
. Preferably boric acid is dispersed in alcohol with ultrasonic dispersion. Temperature of the vessel is adjusted to 75-85°C and kept at this temperature, minimum 4 hours. Ethyl alcohol reflux is provided.
Mixture B: 10 moles of 6 nanometer sized anatase titanium dioxide PC500 (Millenium Inorganic Chemicals), preferably 0.5 moles of nanosized boron oxide, 0.5 moles of Aerosil 200 (Degussa, Evonik) added to the glass reactor and this mixture is dispersed in 90 moles of water.
Mixture A is added on Mixture B under agitation and the temperature is increased up to 85°C and a gentle agitation is done for 2 hours. 1480g of pure acrylic emulsion (preferably silane modified) is added to the reactor and mixed for 1 hour at 40°C.
Mixture A is prepared as in Example 1. Mixture B is prepared with 6 moles of anatase TiO2
(PC500-Crystal) or <10 nm Hombicat UV100 (from Sachleben), 0.5 moles of nanosized Boron Oxide from American Elements (20-80nm size), 1 mole of Kemira grade Zinc Borate and 60 moles of water.
Mixture A is added on Mixture B under agitation and the reaction is carried out at 80°C for 3.5 hours. 1.25 kg of emulsion polymer (DL420G from Dow) is added to the vessel and treated with the nanocomposite matrix for 90 minutes at 50°C. This nanocomposite can be used as (i) an exterior masonry coating with photocatalytic and fire retardant properties by adding the other necessary ingredients, (ii) and interior mat, or semi mat or satin gloss or glossy wall coating with photocatalytic fire retardant and antimicrobial properties by adding the other necessary ingredients.
A boron integrated photocatalytic sol-gel nanocomposite with an enhanced optical recovery in the UV and visible region, characterized in that
(a) Clusters of particles, each being composed of:
(a.1) titanium dioxide nanoparticles of;
(a.2) nanoparticles of boron oxide;
(a.3) and a network made of condensation products of silane(s) and metalalkoxides and/or metalloidalkoxides and alcohols;
said network encapsulating the nanoparticles in such way that the possible hydrophilic character of nanoparticles is confined inside the clusters and does not express outside;
said network including -O- bridges [optionally -C- bonds] between the nanoparticles of titanium dioxide, the nanoparticles of boron oxide;
(b) at least one resin which is a resin chemically modified by silane(s), siloxane(s) and/or silane(s) coupling agents to impart water resistance and rubbing fastness to said resin,
said resin being linked to particles (a) via -O- bridges and/or -C- bonds;
(c) and possibly a liquid phase, (wherein a part of the resin is possibly dissolved),
said liquid phase being preferably water based;
said nanocomposite being obtained by a process characterized by
the following steps:
-A- Hydrolysis and Condensation step:
• silane(s) chosen from : alkylalkoxysilane, fluoroalkoxysilane, organo-functional silane, amino functional silane,
• and metalalkoxide(s) or metalloidalkoxide(s), in R-OH wherein R corresponds to C1-C10 alkyle,
the metals of the metalalkoxides of the network being selected from: Ti, Tl, Zn, Zr, Al and mixes thereof;
the metalloids of the metalloidalkoxides of the network being selected from: Si, B, Sb and mixes thereof;
Addition of hydrochloric acid, or boric acid, or hydrochloric acid and boric acid,
Heating at a temperature comprised between 50 and 100°C,
Hydrolysis with water and dissolving agent enduring from 4 to 8 hours;
pH being less than or equal to 3;
-B- Metal loading step:
Addition of 20-80 nm nanoparticles of boron oxide to the hydrolysis mixture,
Addition of nanosized metal-oxides, which is 2-50 nm anatase titanium dioxide,
Heating under agitation occurring for 1h-5h at a maximum temperature of 100°C;
-C- Resin Addition step:
Addition of silane, siloxane or silane coupling agent modified-resin,
Heating the mixture at a maximum temperature of 80°C and condensing the resin with the previous mixture;
the condensation time of the resin being 0.5-3 hours, under agitation.
2. Use of the sol-gel nanocomposite according to claim 1, in a paint composition.
3. Use of the sol-gel nanocomposite according to claim 1, in a concrete composition.
4. Use of sol-gel nanocomposite according to claim 1, in a mortar composition.
5. Use of the sol-gel nanocomposite according to claim 1, in a ceramic composition.
6. Use of the sol-gel nanocomposite according to claim 1, in a coating composition for polymer films or glass or ceramic.
Boron-integrierter photokatalytischer Sol-Gel Nanokomposit mit verbesserter optischer Ausbeute im UV- und sichtbaren Bereich, dadurch gekennzeichnet, dass
(a) Cluster von Partikeln, wobei jedes zusammengesetzt ist aus:
(a.2) Boronoxid Nanopartikeln;
(a.3) und einem Netz aus Kondensationsprodukten von Silan(en) und Metalloxiden und/oder Metalloidalkoxiden und Alkoholen;
wobei das Netz die Nanopartikel derart abkapselt, das der möglicherweise hydrophile Charakter von Nanopartikeln innerhalb der Cluster begrenzt ist und sich außerhalb nicht äußert;
wobei das Netz -O- Brücken (wahlweise -C- Verbindungen) zwischen den Nanopartikeln von Titandioxid, den Nanopartikeln von Boronoxid beinhaltet;
(b) mindestens ein Harz, das ein durch Silan(e), Siloxan(e) und/oder Silankopplungsmittel chemisch modifiziertes Harz ist, um dem Harz Wasserfestigkeit und Reibechtheit zu verleihen;
wobei das Harz über -O- Brücken und/oder -C- Verbindungen an Partikel (a) verbunden ist;
(c) und möglicherweise eine Flüssigphase, (worin ein Teil des Harzes möglicherweise gelöst ist), wobei die Flüssigphase vorzugsweise wasserbasiert ist;
wobei der Nanokomposit durch ein Verfahren erhalten wird, das durch die folgenden Schritte gekennzeichnet ist:
-A- ein Schritt von Hydrolyse und Kondensation:
• Silan(en), ausgewählt aus: Alkylalkoxysilan, Fluoralkoxysilan, organofunktionales Silan, aminofunktionales Silan,
• und Metallalkoxid(e) oder Metalloidalkoxid(e), in R-OH, wobei R C1-C10 Alkylen entspricht,
wobei die Metalle der Metallalkoxiden des Netzes ausgewählt sind aus: Ti, Tl, Zn, Al und Mischungen derer;
wobei die Metalloide der Metalloidalkoxiden des Netzes ausgewählt sind aus: Si, B, Sb und Mischungen derer;
Hinzufügen von Salzsäure, oder Borsäure, oder Salzsäure und Borsäure,
Erwärmen bei einer Temperatur zwischen 50 und 100°C,
Hydrolyse mit Wasser und einem Lösungsmittel fortdauernd für 4 bis 8 Stunden;
wobei der pH weniger als oder gleich 3 ist;
Hinzufügen von 20-80 nm Boronoxid Nanopartikeln zum Hydrolysegemisch,
Hinzufügen von Metalloxiden, welches 2-50 nm Anatastitandioxid ist, in Nanogröße,
Erwärmen unter Bewegung für 1 Std. bis 5 Std. bei einer Maximaltemperatur von 100°C;
-C- ein Schritt des Hinzufügens von Harz:
Hinzufügen von Harz, das durch Silan, Siloxan oder Silankopplungsmittel modifiziert ist^,
Erwärmen des Gemisches bei einer Maximaltemperatur von 80°C und Kondensieren des Harzes mit dem vorigen Gemisch;
wobei die Kondensierungszeit des Harzes unter Bewegung 0.5-3 Std. beträgt.
2. Verwendung des Sol-Gel Nanokomposits nach Anspruch 1 in einer Farbzusammensetzung.
3. Verwendung des Sol-Gel Nanokomposits nach Anspruch 1 in einer Betonzusammensetzung.
4. Verwendung des Sol-Gel Nanokomposits nach Anspruch 1 in einer Mörtelzusammensetzung.
5. Verwendung des Sol-Gel Nanokomposits nach Anspruch 1 in einer Keramikzusammensetzung.
6. Verwendung des Sol-Gel Nanokomposits nach Anspruch 1 in einer Beschichtungszusammensetzung für Polymerfilme oder Glas oder Keramik.
Nanocomposite sol-gel photocatalytique intégré au bore avec une récupération optique améliorée dans la région visible et UV, caractérisé en ce qu'
il comprend :
(a) des combinaisons de particules, chacune étant composée de :
(a.1) nanoparticules de dioxyde de titane ;
(a.2) nanoparticules d'oxyde de bore,
(a.3) et un réseau composé de produits de condensation de silane(s) et d'alcoxydes de métaux et/ou d'alcoxydes de semi-métaux et d'alcools ;
ledit réseau encapsulant les nanoparticules de telle sorte que le caractère hydrophile possible de nanoparticules est confiné à l'intérieur des combinaisons et ne s'exprime pas à l'extérieur ;
ledit réseau incluant des ponts -O- [éventuellement des liaisons -C-] entre les nanoparticules de dioxyde de titane, les nanoparticules d'oxyde de bore ;
(b) au moins une résine qui est une résine chimiquement modifiée par un/des silane(s), siloxane(s) et/ou agents de couplage de silane(s) pour conférer une résistance à l'eau et une solidité aux frottements à ladite résine,
ladite résine étant liée aux particules (a) via des ponts -O- et/ou des liaisons -C- ;
(c) et possiblement une phase liquide, (dans laquelle une partie de la résine est possiblement dissoute), ladite phase liquide étant de préférence à base d'eau ;
ledit nanocomposite étant obtenu par un procédé caractérisé par
les étapes suivantes :
-A- Étape hydrolyse et condensation :
- silane(s) choisi(s) parmi : alkylalcoxysilane, fluoroalcoxysilane, silane organo-fonctionnel, silane amino-fonctionnel,
- et alcoxyde(s) de métaux ou alcoxyde(s) de semi-métaux,
dans R-OH dans lequel R correspond à un alkyle en C1 à C10,
les métaux des alcoxydes de métaux du réseau étant sélectionnés parmi : Ti, Tl, Zn, Zr, Al et mélanges de ceux-ci ;
les semi-métaux des alcoxydes de semi-métaux du réseau étant sélectionnés parmi :
Si, B, Sb et mélanges de ceux-ci ;
- Ajout d'acide chlorhydrique, ou d'acide borique, ou d'acide chlorhydrique et d'acide borique,
- Chauffage à une température comprise entre 50 et 100 °C,
- Hydrolyse avec de l'eau et un agent de dissolution durant 4 à 8 heures ;
- pH inférieur ou égal à 3 ;
-B- Étape chargement de métal :
- Ajout de nanoparticules d'oxyde de bore de 20-80 nm au mélange d'hydrolyse,
- Ajout d'oxydes de métaux nanométriques, qui sont du dioxyde de titane anatase de 2-50 nm.
- Chauffage sous agitation pendant 1 h-5 h à une température maximale de 100 °C ;
- C- Étape ajout de résine :
- Ajout de résine modifiée de silane, siloxane ou agent de couplage de silane,
- Chauffage du mélange à une température maximale de 80 °C et condensation de la résine avec le mélange précédent ;
- la durée de condensation de la résine étant de 0,5-3 heures, sous agitation.
2. Utilisation du nanocomposite sol-gel selon la revendication 1, dans une composition de peinture.
3. Utilisation du nanocomposite sol-gel selon la revendication 1, dans une composition de béton.
4. Utilisation de nanocomposite sol-gel selon la revendication 1, dans une composition de mortier.
5. Utilisation du nanocomposite sol-gel selon la revendication 1, dans une composition de céramique.
6. Utilisation du nanocomposite sol-gel selon la revendication 1, dans une composition de revêtement pour des films polymères ou du verre ou de la céramique.