Materials news
Humidity-resistant adhesive films AT THE SAMPE 2006 exhibition in California in May, 3M Aerospace introduced two structural adhesive films for composite and metal bonding in the aerospace industry. Scotch-Weld Structural Adhesive Film AF 555 is a thermosetting, modified epoxy adhesive film. The low volatile organic compound (VOC), 350°F curing adhesive is said to offer an extended out-time and outstanding pre-bond humidity resistance. The second low-VOC adhesive film, AF 500, is designed for use in 250°F curing applications. “Cured and uncured composites can absorb up to 3% of their weight in moisture from the environment,” according to Charles Watkins, marketing manager for 3M Aerospace and Aircraft Maintenance Department. “This can affect the performance of traditional adhesives and compromise the integrity of the composite part. Both of these new adhesives have outstanding pre-bond
Adhesive film AF555 in a honeycomb application.
humidity resistance, allowing them to bond to composite substrates that have absorbed moisture from the environment.” Scotch-Weld Adhesive AF 555 has at least a 120-day outtime, allowing it to provide consistent performance over a longer shelf life, potentially reducing adhesive scrap. AF 500 has a 45-day out-time. Both adhesives are reported to be conformable to complex geometric surfaces, can be
repositioned during the application process and stay in place on a vertical substrate. To obtain maximum durability in moist, corrosive environments, AF 555 and AF 500 are recommended for use with a corrosion inhibiting primer such as 3M’s ScotchWeld Primer EW-5000, or the non-chromated primer, Scotch-Weld Primer EW5000AS.
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REINFORCEDplastics
mer (EVOH) barrier layer which reduces loss of styrene. It also means reduced resin odours, an advantage in closed warehouses and warm climates. The black outer layer protects against the effects of ultraviolet (UV) radiation by reducing transmission of visible light to less than 1% and UV light to under 0.3%. The ECOBULK container is certified according to the safety standard CENELEC TR 50404:
June 2006
Reinforced Plastics will be publishing the official catalogue for the Composites Europe 2006 tradeshow. It will be distributed to all visitors at the exhibition in Essen, Germany, on 20-22 September. Around 200 exhibitors and 3500 visitors are expected at Composites Europe, which is co-located alongside the Aluminium 2006 tradeshow. Composites Europe is organised by Reed Exhibitions and the European composites industry association EuCIA. For further information contact Mark Sherman at Reinforced Plastics; tel: +441865-843208; e-mail:
[email protected].
Roving for weaving
2003 for use in explosive risk zones Ex-zones 1 and 2. Electrostatic charges are dissipated through the conductive outer layer. By eliminating the need for metal sheeting to achieve conductivity, the container also weighs much less than traditional IBCs, saving on shipment costs.
A SINGLE-END E-glass roving is being introduced by Cam Elyaf. The product, WR5, is designed for use in weaving processes. The roving’s characteristics are said to include good unwinding properties, high process performance, no fuzz, fast wetout, and high mechanical properties. It has a silane-based sizing and is compatible with polyester, vinyl ester and epoxy resins. Cam Elyaf reports that WR5 is being requested by weavers for multiaxial and woven applications. It is recommended for marine, building and industrial applications.
DSM Composite Resins; www.dsmcompositeresins.com
Cam Elyaf Sanayii AS; www.camelyaf.com.tr
3M; www.3M.com/aerospace
DSM employs new resin containers DSM COMPOSITE Resins has started using a new conductive container for its resins, developed by industrial packaging company Schütz. The ECOBULK MX-EX-EV intermediate bulk containers (IBCs) have a six-layer wall construction said to to ensure the highest levels of safety and an effective permeation barrier. The container features an ethylene-vinyl alcohol copoly-
Composites Europe show catalogue