High-performance liquid crystal thermosets: Resins for...
Transcript of High-performance liquid crystal thermosets: Resins for...
High-performance liquid crystal thermosets: Resins for marine composite applications
Theo Dingemans, Alan Dow and Edward Samulski, Martino Marchetti (TU-Delft)
E-LASS Seminar Finspång 2016
Extreme Materials for Extreme Applications
ALLOTROPICATECHNOLOGIES
3D Printing
Defense
CommercialAerospace
StockShapes
PolymerAdditives
Marine
High-performance polymers
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ü Shelf life
ü Thermal bonding
ü Post forming possible
– High Temperature use
PEKKTg 156 ºC; Tm 338 ºC
Thermoplastic
ü Ease of processing
ü High temperature use
– Shelf life
– Post forming
Thermoset
ReactiveThermoplastic
Polymers
bisphenol-A diglycidyl ether epoxyTg 190 ºC
Reactive Thermoplastic polymers
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Thermoplastic oligomer (5-10 K)
• Oligomer state makes low viscous melt processing possible (ideal for composites!)
• Reactive end-groups allow for post processing curing: both chain extension and crosslinking is possible
Reactive Thermoplastic polymers
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• High after cure Tg (250–350 oC) and Td5% (>480 oC)
• Low CTE (below Tg: 5.2 oC-1)• low moisture uptake (< 0.05%) and fluid ingress stable• Inherently flame ret. (com LCPs are typically UL94-V0)• LCP have excellent track record in marine applications
(stable in UV and salt water and wear resistant)
Oligomer is liquid crystalline (LC), which means the polymer chains are rod-like and closely packed
Thermal properties cured films
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!
When the LC oligomer is cured a Liquid Crystalline Thermoset or LCT is obtained
Cured neat films:
Ø20 x 5 x 0.25 mmØHeating rate 2 oC/minØFrequency 1 Hz
Thermal properties cured films
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!
When the LC oligomer is cured a Liquid Crystalline Thermoset or LCT is obtained
Cured neat films:
Ø20 x 5 x 0.25 mmØHeating rate 2 oC/minØFrequency 1 Hz
Thermal properties cured films
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LCT creep vs PPS and PEKK (neat resins only!)
Ø20 x 5 x 0.25 mmØHeating rate 2 oC/minØFrequency 1 HzØForce: 1–1.2 N
50 100 150 200 250 300 350 400 450106
107
108
109
101 0
Strain [%
]
E' P
PS [P
a]
Temperature [°C]
HBA/BP/TA(15)-NDA(5)-5k PEKK PPS
E' P
EKK
[Pa]
E'
HBA
/BP
/TA(
15)
-ND
A(5
)-5k [P
a]
0102030405060708090100110
P EKK s train
P PS s tr ain
HBA /BP/TA( 15)-NDA(5)-5k stra in
Stra in 5%
Tg = 270 °C
Applications
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LCT is typically in film, powder or granulate form (infinite shelf-life) and can be processed into machinable stock shapes, foams, coatings, adhesives and composites:
LCT-A LCT-A (salt-spray)5
10
15
20
25
Pull-
off s
tren
ght (
MPa
)
25,7 MPa
22,2 MPa
(a) (b)
Coating
Adhesive
Al
Steel
(1000 h salt spray)
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RheologyCompressed powder pellets, 1% strain, 5 rad/sec, 5 oC/min
20 40 60 80100
101
102
103
104
105
106
Com
plex
vis
cosit
y |η
|* [P
a s]
Time [min]
240
260
280
300
320
340
360
380Tem
perature [°C]
20 40 60 80100
101
102
103
104
105
106
Com
plex
vis
cosit
y |η
|* [P
a s]
Time [min]
0 N
240
260
280
300
320
340
360
380Tem
perature [°C]
20 40 60 80100
101
102
103
104
105
106
Com
plex
vis
cosit
y |η
|* [P
a s]
Time [min]
0 N 1 N
240
260
280
300
320
340
360
380Tem
perature [°C]
20 40 60 80100
101
102
103
104
105
106
Com
plex
vis
cosit
y |η
|* [P
a s]
Time [min]
0 N 1 N 2.5 N
240
260
280
300
320
340
360
380Tem
perature [°C]
20 40 60 80100
101
102
103
104
105
106
Com
plex
vis
cosit
y |η
|* [P
a s]
Time [min]
0 N 1 N 2.5 N 5 N 240
260
280
300
320
340
360
380Tem
perature [°C]
Composite processing
LCT suitable for melt prepreging or pultrusion of fibres
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Composite processing
- Composite stack: 6 plies, 60/40 volume, glass fibre fabric
- Type of yarn: EC9 68, 8 harness satin; Fabric thickness: 0.23 mm. 5 N – 5k
10 c
m
10 c
m
5 N – 10k
LCT powder
Cone calorimetry tests
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Heat release and smoke production according to ISO 5660-1
Per Blomqvist (SP)
Cone calorimetry tests
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How to compare to a well-known epoxy resin?
Bis F epoxy/glass (30/70). ASTM E-1354-04 at 50kW/m2
Fire Mater 2009; 33:323–344.
Cone calorimetry tests
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Test results from ISO 5660-1 were used to predict the behaviour of glass/LCT in a ISO 9705 room-corner test
100 kW
300 kW
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• Cured LC thermosets (LCTs) offer high Tg’s (200–350 oC), lowcreep, low CTE’s, low moisture absorption and fluid stability
• Reactive LC oligomers exhibit low melt viscosities, which makesthem ideal candidates for (highly filled) short- and continuousfibre reinforced composites
• LCT can be processed into composite panels that can bethermally formed on-site (e.g. stamp forming)
• LCT–glass composites show good room temperature mechanicalproperties
• LCT-glass composites exhibit low flammability and hence showpromise for marine structural (composite), coating, insulatingfoam and adhesive applications
Conclusions
Acknowledgements
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TU-DelftMartino Marchetti, Mazhar Iqbal and Alwin Knijnenberg
TencateJoris Markenstein and Hans Luinge
AirbornePeter Coppens
SP GroupPer Blomqvist
Industrial partners (M2i)Fokker, Tencate, SKF, TPRCand Promoulding