General Datasheet
PDS-SE70-15-0618 1
SE 70
LOW TEMPERATURE CURE HIGH TOUGHNESS
EPOXY PREPREG SYSTEM
Low temperature 70 C (158 F) curing
Faster cycle times at elevated temperature
Excellent balance of mechanical properties and toughness
Long out-life up to 4 weeks @ 18-22 C (64-72 F)
Range of compatible adhesive films and ancillary products
Excellent surface finish
Good Tg
Suitable for vacuum bag, press or autoclave consolidation
INTRODUCTION
SE70 is part of the range of prepreg products. This unique product range provides technically and commercially
competitive engineering materials, ideal for use either solely, or in conjunction with other products from within the
product range along with other Gurit products.
SE70 is a hot melt epoxy prepreg ideally suited to the manufacture of thick
sections. It can be cured at temperatures as low as 70 C (158 F), but can
also be used for the rapid manufacture of components through its 25-minute
cure at 120 C (248 F). All of this can be achieved together with out-life of 28
days at 21 C (70 F).
SE70 is designed for vacuum bag pressing and offers excellent mechanical
performance on glass fibre reinforcements. Currently SE70 is manufactured
into a prepreg structure with E-glass and Carbon fibres, which are
manufactured into biax or woven materials. This data sheet is concerned with
carbon reinforcements.
PDS-SE70-15-0618 2
PROCESSING NOTES – GENERAL
PROCESSING NOTES
PREPARATION
When preparing the lay-up the prepreg should be removed from the
freezer and allowed to thaw in a sealed bag. This may take 6 to 24
hours depending on roll size. This prevents atmospheric moisture
from condensing on the prepreg which may cause voiding on cure.
The mould surface should be release coated and must have been
tested for vacuum integrity prior to lay-up.
LAYING-UP
The following procedure is recommended for preparing vacuum
cured laminates.
1. The moulding surface must first be treated with a suitable release
agent. A separate prepreg nylon peel ply is available for covering
the mould tool prior to layup in order to leave a clean, textured
surface for subsequent bonding. The required number of plies of SE
70 prepreg are placed on the tool and a thermocouple inserted into
the layup near the centre ply of the thickest edge section. Typically
several vacuum debulks are required during the layup to ensure the
removal of entrapped air. The frequency and temperature of
debulks can vary depending on the type and size of application. The
user should carry out test panels to determine the optimum
schedule. Further advice can be obtained from Technical Services.
2. Apply a peel ply to the surface of the layup. Note that for good
secondary bonding of a peelplied surface of an SE 70 prepreg
laminate, a nylon peel ply, such as Tygavac stitch Ply A is strongly
recommended. Cover the peel ply entirely with a perforated release
film. Normally, no edge resin bleeder system is used. P98 grade
release film is recommended. With the perforated release film, the
amount of resin bled away is controlled by the number of dry plies of
resin bleeder cloth placed over the perforated release film. For thin
skins care must be taken not to overbleed the laminate (prepreg
peel ply and low bleed RP2 release film will ensure this does not
occur).
3. Install a vacuum bag by standard techniques. Insert at least two
vacuum stems through the bag connecting one to the vacuum
source and the other, at a point on the part furthest from the source,
to a calibrated vacuum gauge. Position part in the oven or autoclave
and draw vacuum to check for bag or system leaks.
4. Commence the heatup cycle, typically between 0.3 C(0.5 F)/min
and 2 C(3.6 F)/min to the final cure temperature. At 70 C (158 F)
the temperature should be held for 16 hours. Faster cures may be
obtained at elevated temperatures, e.g. 100 mins @ 100 C (212 F),
or 25 minutes @ 120 C (248 F). All temperatures should be
measured by the previously installed thermocouple. When curing at
70 C (158 F), a minimum of 16 hours is recommended. Vacuum
should be maintained as high as possible, with a minimum of 85%
throughout the cure cycle.
5. Upon completion of cure, the heat is turned off and the part
cooled until its temperature has fallen below 60 C (140 F). When
fully cooled, the part may be debagged, trimmed and machined as
necessary. A post-cure is not required.
Gloves should be worn both to avoid skin contact with the prepreg,
and to avoid transfer of sweat onto the prepreg, which may cause
voiding on cure.
THIN LAMINATES
When using very thin laminates (eg with a total laminate fibre
weight of less than 300g/m
2
), care needs to be taken to avoid
extracting excessive amounts of resin during the cure
process. To avoid this, a microporous release film can be
used, and for particularly critical components, a pre-
impregnated peel ply should be used before the application
of a RP2 perforated release film and breather / bleeder
fabric.
THICK LAMINATES
When processing thick laminates, extra care should be taken
to avoid entrapping air in the laminate by the use of regular
vacuum debulks.
An intermediate dwell can be included during the cure to
burn off any excess exothermic energy in a controlled
manner. Contact Technical Services for further details.
CURING ON A RELEASE COATED MOULD
Several thermocouples should be positioned at various parts
of the layup; a minimum of 12 is recommended but this may
vary depending on the size of the moulded structure.
On a well sealed mould tool it should be possible to achieve –
0.85 bar. If the achievable vacuum is below this level do not
proceed with cure until the bag leaks have been plugged.
The vacuum should be held at ambient temperature for one
hour prior to heating. The vacuum should be maintained
throughout the cure. Acceptable ramp rates vary from 0.3–
2.0 C (0.5-3.6 F) per minute, with 0.3-0.5 C/min (0.5-
3.6 F/min) being typical on large structures.
When curing large structures a dwell period can be included
to allow temperature equilibration of the tool and laminate.
See separate Processing Notes for further information.
For a good balance of composite properties, it is
recommended that the laminate is cured at 70 C (158 F) for
a minimum of 16 hours. A laminate may be cured in two
stages if, for example, making a cored component. However
in a two stage cure, a minimum of 8 hours at 70 C (158 F) or
4 hours at 80 C (176 F) is recommended before debagging
a skin, and it must be ensured that this skin is cured for the
equivalent of at least 16 hours at 70 C (158 F) or 8 hours at
80 C (176 F) before going into service.
CURING AT 70 C ( F)
When curing at 70 C (158 F) it is important to ensure the
temperature is monitored off the trailing thermocouple as
70 C (158 F) should be treated as the minimum cure
temperature for SE 70.
CURING AT HIGHER TEMPERATURES
SE 70 may be cured at higher temperatures for a shorter
time. At a cure temperature of 100 C (212 F) cure can be
achieved in 100 minutes, or at 120 C (250 F) cure can be
achieved in 25 minutes.
It is not recommended to cure SE 70 under vacuum
pressures of less than 0.85 bar. If a ramp rate of less than
0.3 C(0.5 F)/min is used, users should satisfy themselves
that this allows adequate flow.
PDS-SE70-15-0618 3
PRODUCT INFORMATION
AVAILABILITY
SE70 prepregs are available in a variety of fabric forms, normally
supplied on a single polythene film. Please contact Technical
Services to discuss specific requirements and availability.
PROPERTY UNIT
200GSM HEC UD
CARBON
Tack rating *Medium
Nominal Resin Content (by weight) % 37
Nominal Fibre Weight g/m
2
200
Nominal Areal Weight g/m
2
317
Nominal Roll Width mm 400
Nominal Roll Length Lm 20
Backer –
1 x paper / 1 x MDPE
poly
*allows repositioning of plies at recommended handling temperature
PREPREG PROPERTIES
RHEOLOGY DATA
SE70 resin viscosity profile conducted at 1 C (1.8 F) per minute.
TRANSPORT & STORAGE
When stored sealed & out of direct sunlight.
PROPERTY VALUE
Minimum Viscosity 37.6 Pa.s 376 P
Temperature at Minimum Viscosity 69 C 156 F
STORAGE TEMP UNIT VALUE
-18 C 0 F months 24
+18-22 C +64-72 F weeks 4
All prepreg materials should be stored in a freezer when not
in use to maximise their useable life, since the low
temperature reduces the reaction of resin and catalyst to
virtually zero. However, even at -18 C (0 F), the temperature
of most freezers, some reaction will still occur. In most cases
after some years, the material will become unworkable.
When not in use SE 70 products should be maintained at –
18 C (0 F). To avoid contamination on their surfaces, allow
rolls to reach room temperature before unwrapping.
HEALTH AND SAFETY
Please refer to product SDS for up to date information
specific to this product.
MINIMUM CURE TIME & TEMPERATURE
Recommended minimum cure is 16 hours at 70 C (158 F) using vacuum bag processing.
PROPERTY OVEN / VAC BAG TEST STANDARD
Typical Laminate 8 plies of 200g/m
2
HEC UD carbon 37% resin content –
Typical Ramp Rate 1 2 C (2 4 F) per minute –
Cure Temperature 70 C (158 F) 80 C (176 F) 95 C (203 F) 110 C (230 F) 120 C (248 F) –
Cure Dwell Time 16 hours 8 hours 4 hours 50 minutes 25 minutes –
Cure Pressure -1bar (14.5Psi) –
De-mould Temperature < 60 C / 140 F -
Dry Tg1 (DMA) 89 C / 192 F 101 C / 214 F 110 C / 230 F 126 C / 259 F TBD ISO 6721 (DMA)
*suitable for use in conjunction with hot-in / hot-out rapid component manufacture is possible using appropriate press tooling
10
100
1000
10000
30 50 70 90
COMPLEX VISCOSITY (P)
TEMPERATURE ( C)
PDS-SE70-15-0618 4
LAMINATE PROPERTIES
Where possible properties presented are averages of multiple batch data from a variety of fibre suppliers. Customers with specific
requirements should contact Gurit technical support who can recommend appropriate fibres and formats.
CURED RESIN PROPERTIES
Oven cured using standard processing techniques and a minimum cure time of 16 hours at 70 C (158 F).
PROPERTY SYMBOL SE 70 RESIN CAST TEST STANDARD
Tensile Strength T 54 MPa 7.83 ksi ISO 527-2
Tensile Modulus ET 3.61 GPa 0.52 Msi ISO 527-2
Flexural Strength F 80 MPa 11.6 Ksi ISO 178
Flexural Modulus EF 3.45 GPa 0.50 Msi ISO 178
Compressive Strength C 142 MPa 20.6 Ksi ISO 604
Compressive Modulus EC 3.81 GPa 0.55 Msi ISO 604
UNIDIRECTIONAL LAMINATE PROPERTIES
Cured using standard processing techniques and a minimum cure time of 16 hours at 70 C (158 F).
PROPERTY SYMBOL UNIT HEC FIBRE* IMC FIBRE* HMC FIBRE* TEST STANDARD
Typical Fibre Density fibre g/cm
3
1.8 1.79 1.82 -
Fibre Modulus Efibre GPa 227 - 257 275 - 310 365 - 405 -
Resin Content % % 32 - 35 35 - 37 33 ASTM D 3171 Method II
Fibre Volume Fraction t % 54.2 52.0 56.1 ASTM D 3171 Method II
0 Tensile Strength** XT MPa 2510 2896 1916 ISO 527-5
0 Tensile Modulus** Et GPa 133 171 211 ISO 527-5
0 Compressive Strength** XC MPa 1174 1295 1191 SACMA SRM1-94
0 Compressive Modulus** EC11 GPa 119 151 195 SACMA SRM1-94
90 Tensile Strength YT MPa 48 42 30 ISO 527-5
90 Tensile Modulus ET22 GPa 7.7 7.1 7.0 ISO 527-5
0 Flexural Strength XF MPa 1295 - - ISO 14125
0 Flexural Modulus EF11 GPa 100 - - ISO 14125
0 ILSS XILSS MPa 78 78 52 ISO 14130
*HEC = High Elongation Carbon, IMC = Intermediate Modulus Carbon, HMC = High Modulus Carbon, UHMC = Ultra-High Modulus Carbon
**Normalised to 60% fibre volume fraction
MULTIAXIAL LAMINATE PROPERTIES
Oven cured using standard processing techniques and a minimum cure time of 16 hours at 70 C (158 ).
PROPERTY SYMBOL UNIT XC411 TEST STANDARD
Resin Content
-
% 42 ASTM D 3171 Method II
Cured Ply Thickness
-
mm 0.46 ASTM D792
Fibre Volume Fraction
-
% 49.2 ASTM D 3171 Method II
45 Tensile Strength* XT
MPa 1414 ISO 527-4
45 Tensile Modulus* Et GPa 66 ISO 527-4
45 Compressive Strength* XC MPa 655 SACMA SRM1-94
45 Compressive Modulus* Ec GPa 59 SACMA SRM1-94
45 Flexural Strength XF MPa 911 ISO 14125
45 Flexural Modulus EF11 GPa 51 ISO 14125
ILSS M MPa 44 ISO 14130
*Normalised to 55% fibre volume fraction
PDS-SE70-15-0618 5
NOTICE
All advice, instruction or recommendation is given in good faith but the selling Gurit entity (the
Company) only warrants that advice in writing is given with reasonable skill and care. No further
duty or responsibility is accepted by the Company. All advice is given subject to the terms and
conditions of sale (the Conditions) which are available on request from the Company or may be
viewed at Gurit s Website: www.gurit.com/terms-and-conditions.aspx
The Company strongly recommends that Customers make test panel s in the final process
conditions and conduct appropriate testing of any goods or materials supplied by the Company prior
to final use to ensure that they are suitable for the Customer s planned application. Such testing
should include testing under conditions as close as possible to those to which the final component
may be subjected. The Company specifically excludes any warranty of fitness for purpose of the
goods other than as set out in writing by the Company. Due to the varied nature of end-use
applications, the Company does, in particular, not warrant that the test panels in the final process
conditions and/or the final component pass any fire standards.
The Company reserves the right to change specifications and prices without notice and Customers
should satisfy themselves that information relied on by the Customer is that which is currently
published by the Company on its website. Any queries may be addressed to the Technical Services
Department.
Gurit is continuously reviewing and updating literature. Please ensure that you have the current
version by contacting your sales contact and quoting the revision number in the bottom left-hand
corner of this page.
TECHNICAL CONTACT INFORMATION
For all other enquiries such as technical queries:
Telephone + 44 1983 828000 (08:30 17:00 GMT)
Email technical.support@gurit.com
24-HOUR CHEMICAL EMERGENCY NUMBER
For advice on chemical emergencies, spillages, fires or exposures:
Europe +44 1273 289451
Americas +1 646 844 7309
APAC +65 3158 1412
All trademarks used or mentioned in this document are protected by law.
E customer.support@gurit.com
W www.gurit.com