Knowde Enhanced TDS
Identification & Functionality
- Chemical Family
- Polymer Name
- Composite Materials Functions
- Technologies
Features & Benefits
- Materials Features
- Product Highlights
- Robust OOA/VBO system
- Capable of freestanding post cure for higher Tg
- Flexible cure prepreg system
- Excellent resistance to hot/wet exposure
- Long out time and tack life for shop floor handling
- High toughness
Applications & Uses
- Markets
- Composites Processing Methods
- Recommended Applications
- Launch
- Space & Satellite
- Aerostructures
- Thick parts cured under low pressure
- Honeycomb stiffened parts
Properties
- Physical Form
- Typical Properties
- Thermal Properties
| Value | Units | Test Method / Conditions | |
| Density | 1.17 | g/cc | — |
| Gel time at 177°C (350°F) | 9–25 | minute | — |
| Value | Units | Test Method / Conditions | |
| Tg by DMA after 6 hours at 135°C (275°F) | 168 (334) | °C (°F) | — |
Storage & Handling
- Shelf Life
- Out Life: Up to 28 days at ambient
- Frozen Storage Life: 12 months at -18°C (< 0°F)
Out life is the maximum time allowed at 21°C (70°F) or below and 60% or less RH before cure, after a single frozen storage cycle in the original unopened packaging at -18°C (0°F) or below for a period not exceeding the frozen storage life noted above. * Out life tested by SBS on 16-ply 15 x 15 cm (6 x 6 in.) laminate, cured in a out-of-autoclave/vacuum bag only (OOA/VBO) environment with 914–948 mbar (27–28 inHg). Users may need to evaluate out life limits for their own Applicationss due to differing thickness, configuration, and complexity.
- Product Handling
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 out life at room temperature; however, the life and performance of the material is best preserved with the following basic guidelines. Refer to the frozen storage life included in the product certifications. The epoxy material should be sealed in an airtight bag and kept frozen below -18°C (0°F) when not being used to assure the longest life and most consistent performance. It is also best practice to include active desiccant in the core of the prepreg roll to provide protection from moisture ingress.
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MOISTURE ABSORPTION AND SENSITIVITY: While very resistant to moisture absorption after cure, epoxies can be adversely affected by moisture uptake prior to cure. For this reason, all materials must be completely thawed to room temperature prior to opening the sealed bag to avoid condensation on the material. Also, it is good practice to keep prepreg and in-process hardware in a sealed bag or vacuum bag if it will be exposed to the atmosphere for significant periods of time.
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HANDLING OF MATERIALS: When handling any prepreg materials, one should always wear clean, powder-free latex gloves. This will assure that no hand oils are transferred to the prepreg or composite during processing. The presence of oils in the part could lead to problems with mechanical and electrical performance of the part. This also helps protect against dermatitis that may occur with some users.
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NONMETALLIC HONEYCOMB AND FOAM CORE USE: When using nonmetallic honeycomb and foam core materials for sandwich structures, the materials should always be dried in an oven prior to lay-up to drive off any moisture or volatiles that may be in the core. The core should be cooled and sealed with desiccant to avoid moisture re-uptake. Following drying, the material should be used as soon as possible.
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DEBULK LAY-UP MATERIAL SEQUENCE FROM TOOL SURFACE TO BAGGING MATERIALS:
- Bottom tool
- Non-porous FEP
- Prepreg
- Porous TX1040
- Non-porous FEP
- Caul plate
- Vacuum bag
A robust debulking procedure is necessary to minimize entrapped air between plies as shown in Figure 1. Vacuum level should be at least 914 millibars (27 inHg). TC275-1E UD tape was debulked every 4 plies for 5–10 minutes. TC275-1E woven fabric was debulked every 2 plies for 5–10 minutes. An additional ply of porous Teflon coated glass (TX1040) was used to help with the removal of entrapped air, and it was replaced every 2–3 cycles.