Tooling & Composites Product Data Sheet Version 05 / 2017 Biresin® CR170 with Biresin® CH170-3 Hardener Composite resin system | Product Description Biresin® CR170 resin cured with Biresin® CH170-3 hardener (B) is an epoxy resin system suitable for the production of high performance fibre reinforced components by the RTM process, especially where high thermal performance, up to 180°C, is required. Areas of Application Biresin® CR170/CH170-3 is especially suited to injection processes due to its viscosity range and reactivity. The resin should be processed at elevated temperatures (60°C) and used in areas where high thermal performance is required, for example in the production of automotive parts. Features / Advantages ■i Low mixed viscosity at processing temperature (60°C) leads to a fast and effective wetting of dry fabrics and nonwovens ■ Glass transition temperatures up to 170°C are possible depending on curing conditions Processing and processing properties ■ The material and processing temperatures should be in the range 18 - 35°C. ■ The mixing ratio must be followed accurately to obtain best results. Deviating from the correct mix ratio will lead to lower performance. ■ Before demoulding precuring of at least 2 h at 60°C is recommended. ■ The final mechanical and thermal values are dependent on the applied postcuring cycles. ■ It is recommended to clean brushes or tools immediately after use with Sika Reinigungsmittel 5. ■ Additional information is available in “Processing Instructions for Composite Resins”.

Typical Mechanical Properties of Fully Cured Neat Resin Thermal Data, neat resin specimen: approx. values after 3 h / 60 and 4 h / 160°C The test specimens were produced from 3 mm thick pure resin. Before the above postcuring, the samples were cured for 7 days at 23°C. When curing a composite part, the whole of the part (including the very middle of the laminate) needs to see the cure temperature. BUILDING TRUST

Postcuring The suitable cure cycle and the attainable mechanical and thermal values depend on various factors, such as laminate thickness, fibre volume, reactivity of the resin system etc. An appropriate cure cycle could look as follows:  Heat-up rate of ca. 0.2°C/Minute until approx. 10°C below the required glass transition temperature (Tg)  Followed by a dwell at that temperature of between 2 and 12 hours.  Part(s) should then be cooled at ~0.5°C per minute The specific postcure should be adapted to the required technical and economic requirements. To measure the mechanical performance...