Toray BT250E-1 PRODUCT DATA SHEET DESCRIPTION Toray BT250E-1 resin system is a 121°C (250°F) cure epoxy prepreg system with excellent toughness and strength. It provides an outstanding surface finish under vacuum-bag/oven-cure only. The resin system, which is self-adhesive to honeycomb and foam core, is MIL-R-9300 qualified and makes a great choice for many applications in the low-tomedium-service temperature range. system for out of autoclave cure for good impact resistance ff MIL-R-9300 qualified ff Ideal for low-to-medium service temperature applications ff Toughened PRODUCT TYPE TYPICAL NEAT RESIN PROPERTIES 121°C (250°F) Cure, Epoxy Prepreg System Moisture Absorption 2.0% after 24 hr water boil Tensile Strength Tensile Modulus Tensile Strain SHELF LIFE Loss Tangent fSecondary aircraft structures f fRadomes with glass, quartz, and Kevlar® f fReflectors f fSporting goods f fKnee braces and other related medical items f fGeneral purpose composites f Dielectric Constant TYPICAL APPLICATIONS Tack Life: Compression Strength Compression Modulus Frozen Storage Life: Flexural Strength Flexural Modulus Flexural Strain Dielectric Constant at 10 GHz on 4581 quartz Loss Tangent at 10 GHz on 4581 quartz Tack life is the time during which the prepreg retains enough tack, drape, and handling for component lay-up. Out life is the maximum time allowed at ambient temperature before cure. *Ambient is 18–22°C (65–72°F) *Out life tested by SBS on 8-ply 15 x 15 cm (6 x 6”) fabric laminate, cured in an out-of-autoclave/vacuum-bag only (OOA/VBO) environment with 914–948 mbar (27–28 inHg). Users may need to separately evaluate out life limits on thicker, larger, and more complex parts. Contact us for more information: North America/Asia/Pacific e [email protected] t +1 408 465 8500 Europe/Middle East/Africa e [email protected] t +44 (0)1773 530899

Toray BT250E-1 PRODUCT DATA SHEET ELECTRICAL PROPERTIES OF COMPOSITE LAMINATES BT250E-1 (7781 Fg) Dielectric Constant Loss Tangent MECHANICAL PROPERTIES Condition Short Beam Shear Strength Laminate data - 7781 Fg reinforcement, 300gsm FAW. * All properties normalized to 60% fiber volume except ILSS. (Fiber volume 40–50%) MECHANICAL PROPERTIES Condition Short Beam Shear Strength (A) Laminate data - 3K PW graphite, 250gsm FAW. (B) Laminate data - 3K 8HS graphite laminate, 368gsm FAW. *All properties normalized to 60% fiber volume except ILSS. (Fiber volume 40–50%) Contact us for more information:...

Toray BT250E-1 PRODUCT DATA SHEET BT250E-1 Epoxy Prepreg: Cure cycle Hold at 127°C (260°F) for 2 hours minimum. *Part must be dwell at this temp. Oven temperature may not reflect actual part temperature. • Apply 25 inHg vacuum minimum. Heat up at 1–3°C (2°–5°F)/min Below 71°C (160°F), release pressure and remove. (Temperature based on lagging thermocouple) • Apply 1–3.4 bar, 0–100 psi 3 pressure to autoclave (optional).

Toray BT250E-1 PRODUCT DATA SHEET EPOXY PREPREG, ADHESIVE, AND RESIN GUIDELINES AND HANDLING PROCEDURES The following guidelines are provided to our customers to assure that best practices are used to attain the best results from Toray Advanced Composites epoxy products. Keep in mind that these procedures represent best practices for all composite prepreg and adhesive materials. FREEZER STORAGE Epoxy resin materials have good shelf life at room temperature; however, the life and performance of the material is best preserved with the following basic guidelines. Refer to the shelf life included...

Toray BT250E-1 PRODUCT DATA SHEET TYPICAL COMPOSITE LAMINATE STACKING SEQUENCE List of Materials 1. Tool – aluminum, steel, Invar, composite (tool plates must be release coated or film covered). 2. Release coat or film – Frekote 700NC or 770NC, FEP, TEDLAR Lay-up part using standard debulking procedures 3. Silicone edge dams for cure – slightly thicker than laminate 4. Laminate 5. Release coat or film – Frekote 700NC or 770NC, FEP, TEDLAR 6. Caul plate – aluminum, steel, Invar, silicone rubber sheet (metal caul plates must be release coated or wrapped) 7. 2.2 oz/yd2 polyester breather, 1 or more...