Master Bond EP21TDC-4ND is a two component, very flexible epoxy system for high performance bonding, sealing and coating with a non-drip consistency. It has a one to four mix ratio by weight. EP21TDC-4ND has a room temperature cure that can be accelerated by adding heat. The best cure schedule is overnight at room temperature followed by 3-4 hours at 150-200°F. A peculiar feature of this product is that straight heat curing results in a product that is slightly softer (Shore A 60), than the one with the optimum cure (Shore A 75). The cured system has a peel strength greater than 30 pli and an elongation of over 200%. EP21TDC-4ND bonds well to a wide variety of metals, plastics and especially rubbers. In fact, it may adhere well to untreated rubber materials such as neoprene, nitrile, SBR and occasionally EPDM rubber compounds; materials that normally require time consuming surface preparation. The cured system has solid electrical insulation properties along with good chemical resistance to oils and water. The epoxy has superior resistance to aggressive thermal cycling along with impressive resistance to mechanical shock and vibration. EP21TDC-4ND has an exceptionally long open time greater than 90 minutes. It has a service temperature range of -100°F to +250°F, with superb low temperature serviceability. It is widely used in OEM, electrical, electronic, repair and maintenance type applications.
Product Advantages
- Convenient mixing: non-critical, one to four mix ratio, by weight, available in premeasured kits
- Smooth paste viscosity; non-drip type system
- Versatile cure schedules: ambient temperature cures or faster elevated temperature cures
- High peel strength and exceptionally robust resistance to thermal cycling and shock
- Bonds especially well to rubber including neoprene, nitrile, SBR and occasionally EPDM
- Outstanding resistance to thermal cycling
