SILICONE SURFACE IMPREGNATION & COATING · SILICONE SURFACE IMPREGNATION & COATING Textiles...
Transcript of SILICONE SURFACE IMPREGNATION & COATING · SILICONE SURFACE IMPREGNATION & COATING Textiles...
Paperlabel-release, bakery paper…
Building Materialsstones, concrete, wood…
SILICONE SURFACE IMPREGNATION & COATING
Textilesairbags, sportswear, lingerie…
but also:tires, ships, corks, etc.
Bond Bond energy
Si – OC – C
106 kcal/mol85 kcal/mol
Chain Valence angle
Si-O-SiO-Si-OC-C-C
130-140°110-115°110°
Si
O
Si
O
Si
CH3 CH3 CH3 CH3 CH3 CH3
GENERAL PROPERTIES
hydrophobic methyl groups
C-C-C 110°
Chain flexibility – Lubrication, hydrophicity, relea se propertieslow Tg (-123°C)low surface energy (~20 mN/m)
Thermal stability, weathering resistanceDurability well above organic polymers
npolar flexible siloxane backbone
Environmental Profile
SiO2 (sand)Elemental
Silicon
Chlorosilanes
Manufacturing
Degradation
Manufacturing
Use UseSilicones
Risks- Degradation (frost , moss, mold...)
- Appearance (efflorescence, spotting..)- Economic (insulaton loss…)Exposure
- Infiltration,- Raising Damp,- Condensation
Moisture in Buildings
Substrates- Roofing (Tiles…)
- Facades (Stones, Bricks,Concrete, Mortar, Stucco)
- Walls (Plaster…)- Wood
Solutions- Surface treatment
- Injection
Silicones Advantages
� Hydrophobia
� Low surface tension -> spreadability
� UV Resistance -> durability
� Water vapor permeability
Silicones Properties
wall
Liquid water
Water vapourexchange
θ
exchange
Beading effect
Molecular treatment (inside of the capillaries)
• water proof (liquid water)• water vapour permeability (open pores)• No surface modification
deep penetration = durable treatment
Con
tact
ang
le (°)
silicone resins on glass
60
90
120
Building protection Basic principles
Prince’s Palace (Monaco) Arc de Triomf (Barcelona) Basilique de Fourvières (L yon) Colonne di San Lorenzo (Milan)
thickness (Å)
Con
tact
ang
le (
0
30
0 100 200 300
resin 1resin 2resin 3
Few molecular layers are sufficient to provide optimum water-repellency
Factors affecting penetration
Building protection with emulsions
2
3
4
dept
h (m
m)
200
250
300
350
mass deposited (g/m
²)
Need a compromise (too reactive if too concentrated)
0
1
2
0 10 20 30 40 50 60 70 80 90 100
% octyl silane in white spirit
dept
h (m
m)
0
50
100
150
mass deposited (g/m
²)
penetration depth (mm)
hydrophobized depth (mm)
mass deposited (g/m²)
250
300
350
volu
me
cum
ulé
en
mm
^3/g Tuffeau
Saint Vaast
Mortier
Typical EmulsionGranulometry
Molecular &Micellar Range
Substrate pore size vs. emulsion droplet sizeM
ercu
ry P
oros
imet
ry
Cum
ulat
ed v
olum
e (m
m3 /
g) Tuffeau St VaastMortar
Building protection with emulsions
0
50
100
150
200
1.00E-03 1.00E-02 1.00E-01 1.00E+00 1.00E+01 1.00E+02
diamètres des pores en µm
volu
me
cum
ulé
en
mm
^3/g
Mer
cury
Por
osim
etry
Cum
ulat
ed v
olum
e (m
m
Pore diameter (µm)
solvent-based and water-based will penetrate differently
Building protection with emulsions
Should we adapt droplet size to pore size?
Rdroplet < Rpore
=> penetration?
Rdroplet > Rpore
=> no penetration?
… not only a matter of relative size!
Should we adapt droplet size to pore size?
When pores are too small:
Favorable for capillarity
Building protection with emulsions
Rdroplet > Rpore
=> no penetration?
Importance of water/oil interfacial tension (droplet deformability) and droplet/solid interfacial tension (=> wetting)
Important parameters are:
Rf mean pore size at frontθθθθws water/solid contact angle=> capillary driving force
Building protection with emulsions
Impregnation of a porous material with an emulsion:
L
Rd RpRL
Rf
θθθθw/s
θθθθo/s
L droplet “position”RL mean pore size along L=> pressure loss along pore
Rd droplet sizeRp pore sizeθθθθos oil/solid contact angle=> droplet wetting and deformation
modified Washburn’s Law, with:
tAtx .1)( β−=
2
2cos4
f
Lwsw
RK
RA
θγ=
θ
Building protection with emulsions
Impregnation of a porous material with an emulsion:
−−=
d
f
p
osf
wsw
oil
R
R
R
R θθγ
γβcos
cos
Allows to describe different penetration regimes (depending on ββββ)
Washburn, Phys Rev. (1921), 17, 273Marmur et al. JCIS (1989), 189, 299
L
Rd RpRL
Rf
θθθθw/s
θθθθo/s
θo/s > 90°
imp
oss
ible
not enoughsurfactantto deform
the droplets
Rel
ativ
e dr
ople
t siz
e (
Rd/R
f)
Regimes of penetration:
Building protection with emulsions
1|cos θo/s|
unhindered
0 αααα |cos θo/s|
θo/s < 90°
1
imp
oss
ible
(αααα = γγγγw/o / γγγγw)
no obstacle
Relative pore size ( Rp/Rf)
Rel
ativ
e dr
ople
t siz
e (
30
40
Pen
etra
tion
Dep
th (m
m)
St Vaast SandstoneConcrete
Penetration depth of different silicone formulation s:
Building protectionwith emulsions
0
10
20
in solvent Emulsion NanoEmulsion MicroEmulsion
Pen
etra
tion
Dep
th (m
m)
Importance of droplet size + derformability
(2x1mn impregnation of 10% active material solutions, allowed to dry out for 48h)
Analysis of silicone penetration:
IR (DRIFT)
Building protection with emulsions
00.10.20.30.40.50.60.70.80.9
1
0 0.2 0.4 0.6 0.8 1
Emuls. 5%
Emuls. 5% + 1%surf.
depth / total depth
rela
tive
DR
IFT
inte
nsity
Excess surfactant help droplet penetration
Should we adapt droplet size to pore size?
When pores are bigger:
Penetration might
Building protection with emulsions
Rdroplet < Rpore
=> penetration?
Penetration might still be hindered,
if affinity between surfactant and solid
is too strong
Rétention de XO80 Sur Tuffeau
0,2
0,4
0,6
0,8
1
1,2
Sig
nal / S
ignal (h
=0)
1%
2%
4%
water
silicone resin
Mortar
Anionic
Surfactant localisation
rel.
DR
IFT
inte
nsity
Importance of interactions between surfactant and s ubstrate:
Building protection with emulsions
High retention0
0,2
0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1
h / h imbibée
Rétention de XO80 Sur Saint Vaast
0
0,2
0,4
0,6
0,8
1
1,2
0 0,2 0,4 0,6 0,8 1
h / h imbibée
Sig
nal / S
ign
al (h
=0)
0,5%
1%
2% water
silicone resin
Mortar
nonionic
Mortar
Surfactant localisation
depth / total depth
depth / total depth
rel.
DR
IFT
inte
nsity
rel.
DR
IFT
inte
nsity
High retention
Low rentention=> deeper treatment
Influence de la concentration en MQTuffeau - 1l / m²
60%
70%
80%
90%
100%
110%
120%
Rep
ris
e e
n ea
u (%
)
2%
4%
2%Water Uptake on TuffeauInfluence de la concentration e n MQ
St Vaas t - 1 l / m²
50%
60%
70%
80%
90%
100%
Rep
ris
e e
n e
au (
%)
2%
4%
6%
8%
10%
2%
Water Uptake on St Vaast
Macroscopic protection : put enough silicone at mac roscopic level
wat
er u
tpak
e (%
)
wat
er u
tpak
e (%
)
increasing [silicone]
increasing [silicone]
Building protection Basic principles
need ≥ 4% silicone
0%
10%
20%
30%
40%
50%
60%
0 5 10 15 20 25 30
Nb de jours
Rep
ris
e e
n ea
u (%
)
4%
6%
8%
10%
10%
28 jours
0%
10%
20%
30%
40%
50%
0 5 10 15 20 25 30
Nb de jours
Rep
ris
e e
n e
au (
%)
28 joursdays days
wat
er u
tpak
e (%
)
wat
er u
tpak
e (%
)need > 10% silicone
[silicone] [silicone]
Solution Impregnation
Porous Substrate:• Specific Surface, S• Specific Porous Volume, Vp
Mean Thickness, h
CVp
h .=
Macroscopic protection : put enough silicone at mac roscopic level
Solution concentration, C
Building protection Basic principles
CS
h .=
Examples : S Vp h C
St Vaast Stone 2 m²/g 0,25 cm3/g 50Å 4%
Tuffeau Stone 15 m²/g 0,31 cm3/g 50Å 24%
knowing basic substrate characteristics can help provide a suitable treatment
Treating porous materials with emulsions can be tri cky,but formulations can be optimized:
Importance of surfactant type and proportion
Concluding remarks
Importance of droplet size but also deformability (play on interfacial tension to allow large droplets to enter smaller pores)
Importance of surfactant interaction with solid (avoid chromatographic retention of surfactants on solids)
WATER REPELLENT(different forms)
� Creams and pastes :are designed more particularly to ensure better penetration of the silanes in concrete. Two problems inherent to this type of formula are identified: form of application in thick coats, which seems restrictive, and the risk of losing active material through volatilisation.
� Microemulsionable concentrates : appear to be fairly economical � Microemulsionable concentrates : appear to be fairly economical solutions (100% active, hydrodispersible but without the need for any excess agitation). Main disadvantage is their very low stability after dilution
SILOXANES VERSUS SILANES
SILANES � small molecules penetrate deeper and more easily� very high reactive site � not necessarily require a perfectly dry surface for application;…but also numerous downsides:� volatility� toxicity (often irritants)� need for humidity and a catalyst to react� low beading effect� risk of leaching where insufficient cross linking.� risk of leaching where insufficient cross linking.� So as to attenuate these disadvantages, possible to use oligomerised or
“advanced” silanes.(= siloxane oligomers )have the following advantages :� less volatile� less toxic� less alcohol salted out;� …but:� the silane’s functionalities are less well distributed throughout the network;� less penetration in non-porous materials.
SILOXANES VERSUS SILANES
SILOXANES� non volatile� very low toxicity� good beading effect as of the first hours� no risk of leaching
…with the following downsides:� high viscosity: sometimes have to be diluted in solvents;� require very dry surface for application;� require very dry surface for application;� molecular weight of several thousand g/mol => poor penetration
That means silane content must be modulated according type of surface/ application conditions. For example a low-porosity surface such as fresh concrete is very reactive, requiring the high penetration of silanes, . On the other hand, a much lower level of silane content is recommended for treating neutral and porous materials
WATER REPELLENT DILUTION (solvent based products)
� Generally: aliphatic (white spirit ,isoparaffin) and aromatic hydrocarbons. Some products( with high silane content )can also be diluted in anhydride alcohols, typically ethanol or 2-propanol (anhydride aspect is essential because of the cross linking before it is applied). These alcohols are suitable for formulations, better compatibility with materials which are sensitive to aromatic solvents potentially exposed during application (tar seals, or polystyrene for example).The type of solvent used will affect the product’s penetration � The type of solvent used will affect the product’s penetration capacity: low-polarity solvents tend to be considered more effective . Their low superficial tension makes them easier to spread on a varied range of surfaces, and their relatively low density is a benefit in the case of treatments by capillarity.
WATER REPELLENT DILUTION (water based product)
� Recommending demineralised water gets round local water hardness variations (content of calcium and magnesium ions). the presence of electrolytes modifies interactions between water and surfactants, and can lead to the and surfactants, and can lead to the destabilisation of droplets and therefore the destruction of the emulsion.
� This risk is in fact fairly limited since most water repellent emulsions tested tend to be non-ionic surfactant based.
Rhodorsil BP 9400 is versatile: it can be used on many porous substrates and is particularly recommended for thetreatement of stone, brick, and « old » concrete (carbonated).
•• Rhodorsil H224 (69% AM) & Rhodorsil BP 9400 (100% AM)Rhodorsil H224 (69% AM) & Rhodorsil BP 9400 (100% AM)
Building Protection : Solvant based products
40
60
80
100Mortier
BriqueGrès Rouffach
hydrofuge standard RHODORSIL BP 9400
Rhodorsil BP 9400 has been certified by CSTC : HD-340/133-150
Generally these products are applied diluted down to 6 -8 % into solvent
020
40
Massangis
St vaast
Tuffeau
Euville
SavonnièreH
••RHODORSIL BP 9710 (44% AM)RHODORSIL BP 9710 (44% AM)
40
60
80
100Mortier
BriqueGrès Rouffach
RHODORSILBP 9710 HYDROFUGE STANDARD"BP 9710 is an emulsion of an alkylpolysiloxane oligomer designed to protect buildings againts moisture.
BP 9710 is versatile : it can be used on many porous substrates , particularly on
Building Protection : Water based product
0
20
40
Massangis
St vaast
Tuffeau
Euville
Savonnière
many porous substrates , particularly on lime stones, sand stones, mortars , renderings or bricks.
Rhodorsil BP 9710 has been certified by CSTC : HD-340/133-151
Generaly, RHODORSIL BP 9710 is diluted between 4% and 8% of active material in water.
RHODORSIL BP 97XX Range
� Rhodorsil BP 9710 : Ready to use water based water repellent : � versatile (performances on many different porous substrates )� good storage stability ( 12 months concentrated / 12 months diluted)� controlled reactivity
� Rhodorsil BP 9705 : Ready to use water based water repellent :� Rhodorsil BP 9705 : Ready to use water based water repellent :� low reactivity � Designed as an additive for various formulations� Stability 12 month
BP9710
PRODUCTS POSITIONNING
• Technology
4
6
8
10Reactivity
Beading effectdurability
Solvant based
Water based
Fluorinated
Waxes
0
2
penetration depth
water repellency
oil repellency
BS1
• BP9710 - 4% on wall
Building Protection : Water based products
• BP9710 - 4% in mortar
• BP9710 - 4% on ciment
BP water repellents after 3 years outdoor exposure
Product X BP9400 untreated BP9710
TUFFEAU : lime stone
north exposure
Product X BP9400 untreated BP9710
SAVONNIERE : lime stone
south exposure
All products have been diluted down to 8% in the appropriate solvent
Damp-proof course system
The aim is to make the capillary network of the material water-repellent to avoid water working its way upwards.
•When the degree of humidity is very high, solvent based Rhodorsil H 224 makes it solvent based Rhodorsil H 224 makes it possible to quickly achieve the required results.
•Standard dilution: 1 part of H 224 for 10 parts white spirit
� BP 9600 : for lime paints
Surface treatment to protect lime paints against water damages (stains ….)
Building Protection : Solvent based products
Building Protection – stone consolidation
Inorganic material loses its binder and cohesion under the action of water and harmful elements, mainly acid, which penetrate it, causing reactions.
RHODORSIL RC are designed to treat materials which show signs of damage show signs of damage � Formation of a new binder to recover the mechanical properties of the substrate.� Reduction of the water absorption (RC 80)
• The Rhodorsil RC70-80-90 Range:
� RHODORSIL RC 70 : based on ethyl silicate
� RHODORSIL RC 80 : based on ethyl silicate + polysiloxane resin
= Consolidation + water repellent action
� RHODORSIL RC 90 : based on ethyl silicate + methylphenylpolysiloxane resin
Building Protection – stone consolidation
� RHODORSIL RC 90 : based on ethyl silicate + methylphenylpolysiloxane resin
= Consolidation : more flexibility and binding effect
Under the action of the residual water in the pores and a catalyst , it is transformed into silicic acid gel.
Si (OC2H5)4 + 4 H2O Si (OH)4 + 4 C2H5OH
200
300
400
Porosity %
24
26
28
30
32
stone untreated
•• The Rhodorsil RC70The Rhodorsil RC70--8080--90 Range90 Range
Building Protection – stone consolidation
Flexural strengthNewtons
Untrea
tedRC 70
RC 80
RC 90
0
100
200
St VAAST
TUFFEAU
SAVONNIERE
size of sample (cm)
0 1 2 3 4 5 6 7 816
18
20
22
décayed strcturehealthy stone
Treated with RC 70
direction of the alteration
After consolidation, the porosity of initial stone is recovered (filling of holes and grain joints).
IntroductionIntroduction
� In France, Building contributes to 43% of the total consumed energy
� Thermal regulations in Europe , (2000,2005,…) comes into a range in France :• 2012 => new building energy consumption = 50kw/m2/year.• 2012 => new building energy consumption = 50kw/m2/year.• 2020 => Buildings with positive energy
� HQE (france) & BREEAM (UK) should be joined in 2012
Studied systems :
Breeze blocks + cement render Breeze blocks + cement render + water repellent + water repellent
� Cement render : • 400 kg of cement / m3 dry sand ,• 400 kg of cement / m3 dry sand ,• water/cement = 0.5.
� Application of 2 coats of render : • 1st coat thickness : 13mm - Drying : 7 days at 23°C and 60% RH • 2nd coat thickness : 7 mm - Drying : 7 days at 23°C and 60% RH
APPLICATIONS
For water repellents : � Application with a brush until substrate
saturation.� Drying 7 days at 23°C 60% RH
systems are then :� Coated with wax � dried at 45°C during 48h,� weighted,� And placed onto the rain apparatus
Rain test :
• water is pulverized with the help of compressed air • 2 blocks can be tested • 2 blocks can be tested at the same time • good repeatability of the results (% water uptake +/- 0.2%)
Results of rain test for water repellents
Breeze block + cement
2,5
3
3,5
4
4,5
wat
er u
ptak
e (%
)
Blank
0
0,5
1
1,5
2
2,5
0 5 10 15 20 25Time (hours)
wat
er u
ptak
e (%
)
BP 9400 8% (SB)
BP 9710 8% (WB)
BP9600 8% (WB)
BP 9500 8% (SB)
Comparison rain test / capillarity test
Water repellentsWater repellents
2
2,5
3
3,5
Wat
er u
ptak
e (%
) BP9400 (8%-WS) rain test
BP9400 (8%-WS) capillarity test
0
0,5
1
1,5
0 5 10 15 20 25
Time (hours)
Wat
er u
ptak
e (%
)
BP9710 (8% water) rain test
BP9710 (8%-water) capillarity
BP9600 (8%-water) rain test
BP9600 (8%-Water) capillarity test
Note :
capillarity test = immersion of the treated face into 3 mm of water
THERMAL LOSS CALCULATION
� Q = U x S x deltaT x h= coeff thermal transmission x Surface x Delta T°C x time (h)
With U = 1 / termal resistance = λ/e = termal conductivity / thicknessAnd λ= λ0 e 0.08 * %humidity
And λ0 = termal conductivity of dry material
Postulates (individual house)� Total surface = 80 m2 of façade, exposed surface= 40 m2.� Chosen place= Nan Yueh in China (1874mm rain/ year)� Number of days with maximal humidity for our system = 50 days for Nan
Yueh � Internal comfort temperature : 19°C. � External temperature when heating (October – April) is 6°C in Nan Yueh.� Price: 1kW.h chinois= 0.0479 euros� λ 0= 1
THERMAL LOSS COST / IMPACT OF SILICON
With water repellent BP9400Breeze block
aloneBreeze blockwith cement render
Saving for one year( / breeze block without cement
render )reference 4.3%
� CalculationQ TOT = Q exposed wet wall + Q exposed wall during drying + Q dry exposed wall + Q non exposed
wall
render )
Breeze block + cement render untreated
Breeze block + cement render
Treated with BP9400
Saving for one year ( / breeze block with cement
render without treatment) reference 13.3%