Wind Turbine Rotor Blades , June 23-24, 2015, Haus der Technik, Essen, Germany Influence of Glass Fibre Sizing and Storage Conditions on Composites Properties Luc Peters and the 3B team
Wind Turbine Rotor Blades , June 23-24, 2015, Haus der Technik, Essen, Germany
Influence of Glass Fibre Sizing and Storage Conditions onComposites Properties
Luc Peters and the 3B team
� 3B-the fibreglass company
� How glass fibre is produced
� How sizings work
� Sizing ageing study
- Rovings
- Fabrics drying
� Conclusions
content
a reference in fibreglass… innovative, entrepreneur and eco-enthusiast
Advantex® is a registered trademark of Owens Corning used under license.
� 3B is part of The Braj Binani Group which is a conglomerate with diversified interests in cement, zinc, glass fibre and composites
Major and dynamic actor in composite reinforcement solutions
� A special focus on thermoplastics, wind energy, performance composites
� 1000 experts building upon a long heritage of 45 years of expertise
� 160 000 tons of glass produced per year
� Innovating and setting new standards within the fibreglass industry based on our two unique high performance and eco-responsible glass technologies: Advantex ® glass and HiPer-tex™
unique glassfibre solutionshigh performance and eco-responsible
…with global presence
� Sales Offices� Europe
� Bruxelles� India� China
� Productions� Birkeland, Norway� Battice, Belgium� Goa, India
� Research & Application Development� Battice, Belgium (Lüttich, 25 km from Aachen)� Activities in Glass – Fibre coating – Composite
to most effectively serve our partners
Chopper
WUCS(Wet Used Chopped Strand)
3
3B glass fibre processes
Winder
Furnace(melting)
Batch House(dosing/mixing)
Glass Raw Materials
Oven(drying-curing)
FORMING = Bushings(fiberizing)
1
23
Sizing(coating )
DR (Direct roving)
1
Fluid Bed Oven(drying-curing-cooling)
Screen
CS(Chopped Strand)
4
Granulator
Oven(drying-curing)
CFM(Continuous Filament Mat)
2
Note : Multi end roving and Chopped Strand Mat from Goa plant not represented here
how sizings (or sizes) work
Size is applied as a water based formulation,
it contains:
� Coupling agent(s) : Provides adhesion between glass surface and the
resin => Silanes, ….
� Film Former(s) : Provides protection and strand integrity to the roving
as well as compatibility with the resin => EP, PU, VE, …
� Lubricant(s) : Provides lubrication and protects the filaments during
processing
� Other Additives : antistat, emulsifier, anti foaming, bactericide, ...
SizingFunction
Role of GF sizing = ensure good transfer of load applied on the composite from the polymer matrix to the glass.
GF sizing are specific to polymer matrix and final application
PA66 - 50%wt GF Poor coating Good coatingTensile strength (MPa) 50 180Notched Impact Strength (kJ/m2) < 5 18
Poor sizing Good sizing
SizingSilane condensation on the glass surface
9
• Function = coupling glass (inorganic) to other sizing ingredients and polymer matrix (organic)
• Chemical nature = functionalized silane
Condensation of methacryloxysilane on glass surface ⇒ covalent bond !!!
Si
O
O
O
H
H
H
CH2 CH2 CH2 O C C
CH3
CH2
O
SiH3 OH +
Si
O
O
O
H
SiH3
H
CH2 CH2 CH2 O C C
CH3
CH2
O
+ H2O
Glass
Si
Si
+ H2O
T°, - H2O
!! Reversible reaction
SizingTypes of Silanes used in thermoset sizings
10
− γ -aminopropyltriethoxysilane � Epoxy resin
− γ-methacryloxypropyltrimethoxysilane � VE and UPE
Si
O
O
O
CH3
CH3
CH3
CH2 CH2 CH2 O C C
CH3
CH2
O
Si
O
O
O
CH2
CH2
CH2
CH2 CH2 CH2
CH3
CH3
CH3
NH2
Sizing
11
− γ-glycidoxypropyltrimethoxysilane � Epoxy resin
Si
O
O
O
CH3
CH3
CH3
CH2 CH2 CH2 O CH2 C CH2
O
H Glycidoxy = Epoxy
Types of Silanes used in thermoset sizings
SizingSilane
12
Stability of silane in water related to hydrolysis – condensation equilibrium
• Silane is hydrolysed in water during sizing preparation ⇒ formation of silanolbonds
• Hydrolysed silane tends to condensate with time and to form silane oligomers
� Solubility � and gel formation ⇒ reduction of sizing stability
� Silane oligomers will not properly cover/react at glass surface ⇒ reduction of composite mechanical properties
Silane Hydrolysis
13
Ageing of composites and sizingin presence of water => loweradhesionReversible reaction ! Main factors: temperature, H20,
Product & Size Ageing: Coupling Agent(s)
14
� Coupling agents:� Amino:
�continue to crosslink and to react with film former � reduced solubility, less wetting by the matrix.
� Methacryl : �when inhibitor is consumed, then can homopolymerise or crosslink if
unsaturated polyester film former �reduce speed of dissolution or solubility in the matrix,.
� Epoxy: �Could progressively react with amine or acid if present� reduced
solubility�Epoxy functionality can be progressively hydrolysed� reduced
reactivity
Sizing ageing and rovings storageconditions impact on mechanicalproperties
Laminate construction (with one roving)
-Dry winding of flat panel: - 4x 845gr/m² = 3380 gr/m2 (4 layers UD roving) at 0°=> laminate of 2 mm
-Infusion in Epoxy resin Hexion RIMR 135/137 at 35°c, full vacuum, 4 products/infusion in most cases4 hours at 90° post-cure
Testing- Tensile at 90 °- Short beam test according ISO 14130.- Glass contents by weight range 72 to 75.5 %
Typical set up of infusion of 4 products in one shot
Products & Conditionning
17
� Pallets from Birkeland plant (rovings have different starting « age » )
- Reference sizing (SE1500) 17-2400 production date : 4/3/2013- New sizing (SE2020) 17-2400 production date : 11/4/2012- New Multi Compatible sizing (W3030)17-2400 production date : 5/9/2013
� Static test before conditioning� Trip to/from Dubai for SE1500 & SE2020 from August to December
� 1 week at -18°C (check Epoxy crystallisation)� 2.5 months in oven at 50OC in Lab (RH=2-3%)
� 2.5 + 2.5 months at 30°/80%RH (21,5 gr H2O / Kg air) � 2.5 +2.5 months at 30°/80%RH in 2 PE bags sealed
Note: 2020 sizing is epoxy specific and 3030 sizing is multi resins (UP, VE, EP) compatibleSE means the sizing is applied on Advantex glass, W means it is applied on HiPer-tex glass
Conditionning room & bobbins
18
BobbinsBobbins insealed PE bags
T°
& R
H in the pallets
which
wentto and back from
Dubai
19
0 10
20
30
40
50
60
70
80
90
0 5
10
15
20
25
30
35
40
45
8/06/2013 8:28
8/08/2013 17:28
8/11/2013 2:28
13/08/2013 11:28:28
15/08/2013 20:28:28
18/08/2013 05:28:28
20/08/2013 14:28:28
22/08/2013 23:28:28
25/08/2013 08:28:28
27/08/2013 17:28:28
30/08/2013 02:28:28
9/01/2013 11:28
9/03/2013 20:28
9/06/2013 5:28
9/08/2013 14:28
9/10/2013 23:28
13/09/2013 08:28:28
15/09/2013 17:28:28
18/09/2013 02:28:28
20/09/2013 11:28:28
22/09/2013 20:28:28
25/09/2013 05:28:28
27/09/2013 14:28:28
29/09/2013 23:28:28
10/02/2013 8:28
10/04/2013 17:28
10/07/2013 2:28
10/09/2013 11:28
10/11/2013 20:28
14/10/2013 05:28:28
16/10/2013 14:28:28
18/10/2013 23:28:28
21/10/2013 08:28:28
23/10/2013 17:28:28
26/10/2013 02:28:28
28/10/2013 11:28:28
30/10/2013 20:28:28
11/02/2013 5:28
11/04/2013 14:28
11/06/2013 23:28
11/09/2013 8:28
11/11/2013 17:28
14/11/2013 02:28:28
16/11/2013 11:28:28
18/11/2013 20:28:28
21/11/2013 05:28:28
23/11/2013 14:28:28
25/11/2013 23:28:28
28/11/2013 08:28:28
30/11/2013 17:28:28
12/03/2013 2:28
12/05/2013 11:28
12/07/2013 20:28
12/10/2013 5:28 RH
(%)
Te
mp
(°C)
Pa
llets to
an
d fro
m D
ub
ai : d
ata
log
ge
r do
wlo
ad
Ce
lsius(°C
)d
ew
po
int(°C
)H
um
idity
(%rh
)
Battice
Antwerpen
Vessel leaves
Dubai Port
Sharja WH, UAE
Leave Dubai Port
Leave Sharja WH, UAE
Rotterdam
Antwerpen
Battice
Se
pte
mb
er
Octo
be
rN
ov
em
be
rD
ec.
Au
gu
st
0
10
20
30
40
50
60
70
80
90
100
0
10
20
30
40
50
60
70
80
90
100
1/01/2013 1/02/2013 1/03/2013 1/04/2013 1/05/2013 1/06/2013 1/07/2013 1/08/2013 1/09/2013 1/10/2013 1/11/2013 1/12/2013
RH (%)
gr H2O/m3
°C Dubai International aiport
Avg temperature
Max temperature
Point de rosee (avg)
Avg RH
Max RH
gr H2O/m3
Pallets trip
2013 Temperature /RH history in Dubai
20Source: http://www.wunderground.com/history/airport/OMDB/2012/5/15/DailyH
Recordings fromthe pallet
Data logger
2013 Temperature /RH historyin Liege / Bierset (close to where bobbins & fabrics were stored)
21
2013 Temperature /RH history in Kristiansand - Norway
22
TTS for SE1500
Roving age
Effect ofpackaging
Effect ofpackaging
TTS for SE1500
Roving age
UD fabric results
When Transverse tensile strength of UD laminates made by dry windingis low (<10MPa), laminates are already full of cracks prior demolding
Laminate quality
TTS for SE2020 and SE/W3030
UD fabric results
Effect of packaging
+ fabric
UD fabric results
TTS for SE2020 and SE/W3030
UD fabrics results
TTS All results
Short Beam Test results
for 2.5monthsfor 2.5months
UD Fabric drying
Epoxy laminate based on 2 «severely aged » SE1500 UD fa bricsTransverse tensile test before and after fabric drying 2 h at 105°C
2400 tex
2400 tex
Both laminates quality looked good, initial H20 in the fabrics was 0,03% (not high)
Drying could only increase the TTS from 12 to 20-22 Mpa (+70-75%)ILSS was improved from 30 to 43-46 Mpa (+43-45%)
As received Dried 2h at 105°C
Conclusions
� As reported from the field, some « old » reference sizings confirmed to be verysensitive to storage conditions (especially temperature) and demonstratedsignificant reduction of Inter Fiber properties over time.
� The newly developed sizings demonstrate much reduced degration over time in rovings and fabrics forms on Advantex and HiPer-tex glasses . They are much less sensitive to temperature, and provide significantly higher initial Inter Fiber Strength.
� After 2 years of storage at normal « western storage conditions», these new sizings still demonstrate excellent Inter Fiber properties.
� Degradation in hot and humid environment (high amount of water in the air) isstill happening most likely at the interface at the glass (hydrolysis of silane)
� Tight packaging can help => ! water might still diffuse through
� Controled moisture level can help (i.e. < 25gr H20 / Kg = 35C / 70%RH)
� Newly developed sizings ensure better laminate properties consistency
Thank you for your attention