Technical Tip Mixing Pre-measured Bipax INTRODUCTION Pre-measured Bipax are an easy-to-use system of packaging for two-part adhesives and encapsulants. A Bipax is a rigid plastic tube that is separated by a leak-proof clamp, which allows the resin system to remain separated from the hardener until ready to use. Packaging material in Bipax has many advantages. It eliminates mixing errors because side is pre-measured and ready to use after proper mixing, allows the operator to mix the material without coming directly in contact and enables the operator to immediately dispense the material right from the Bipax. However, there are a number of guidelines that should be followed when using Bipax. STORAGE Proper storage of the Bipax is essential. Bipax should be stored in the original foil over wrap and according to recommended storage conditions. Detailed information can be found on the product technical data sheet. 2. Slide the clamp off of the Bipax and pull the ends of Bipax to open the pinched area of tube, allowing the resin and catalyst to flow together. Using a wooden spatula or similar tool, push and pull the spatula over the full length of the Bipax for three minutes. Flipping the Bipax over halfway through will ensure a complete mix. Be sure to pay particular attention to the corners of the Bipax and the area where the clamp was located to prevent accumulation of insufficiently-mixed material. 3. Visually inspect for consistent color. If there appears to be any unmixed material, continue mixing for an additional minute until uniform. Cut open Bipax and dispense. 4. To ensure long term performance of the bonded assembly, substrates should be thoroughly cleaned and dried prior to dispensing of material. Improper removal of surface contaminants can cause poor adhesion. CURING HANDLING Good environmental, health and safety practices should be followed when handling Bipax. Proper eye protection and appropriate chemical resistant clothing should be worn to minimize direct contact. Consult the Material Safety Data Sheet (MSDS) for detailed recommendations on the use of engineering controls and personal protective equipment. FILLER SETTLING In some highly filled systems, it is possible for the filler to settle within the Bipax. Prior to removing the separator clamp, be sure to gently knead the resin side to re-suspend all filler. DIRECTIONS FOR USE 1. Remove the Bipax from storage and ensure the product is at room temperature. Remove the foil over wrap and desiccant, and discard. Refer to the Technical Data Sheet for all recommended cure conditions. For alternate cure conditions, please contact technical support. Inadequate cure usually results in diminished product properties. The following guidelines should be used to ensure proper cure: 1. Avoid high humidity conditions. Pre-bake any substrates if the possibility exists that any absorption of moisture could interfere with normal cure conditions as it is released during cure. Moisture on the substrate may lead to poor wetting. 2. Large parts require longer cure times. Make sure parts have reached the required temperature before starting to time the cure process of the adhesive. Page 1 of 2 CRYSTALLIZATION Crystallization in base resins and two-component formulations is a major inconvenience but not an insurmountable problem. If crystallization is observed after removing the over wrap, heat the entire Bipax at 65C for 30-60 minutes. Remove from oven and knead each side to re-dissolve crystals. In any crystals reappear, merely apply heat and re-melt. Allow the Bipax to cool before removing clip to mix. All the crystals must be completely melted as any microscopic unmelted crystals will act as "seeds" and cause the crystallization to return in days. NOTE: If the epoxy is mixed while warm, pot life may be shortened. DE-AIRING Air removal methods include: * De-air in a vacuum after mixing. Pull 0.999 atmosphere or 29.88 inches (759mm) of mercury for 3-10 minutes. Use a container only 1/3 full to compensate for the expansion of material volume during outgassing. Let the material "foam" and rise to several times its liquid height and then "break" and "fall". The vacuum should be continued until most of the gentle bubbling has ceased. NOTE: Excessive exposure to vacuum can drive off low molecular weight reactive and non-reactive constituents of the resin or hardener. Overexposure can cause separation of components. * Centrifuging can also be effective for removing air. Centrifuge syringes for 3-10 minutes. Care should be exercised not to separate components. * Gentle warming the Bipax to 45C will lower the viscosity but will also decrease work life. Page 2 of 2