Capable of tolerating the harsh environments of the medical industry, this new medical grade epoxy adhesive is said to fully comply with the testing requirements of USP Class VI plastics (for biological reactivity testing). This two-component epoxy resists recurrent autoclaving and sterilizations including radiation, steam, ethylene oxide, and chemical sterilizing.
Master Bond (Hackensack, NJ) says the new grade, marketed as EP42HT-2ND2MED (Black), is an excellent electrical insulator with a volume resistivity greater than 1012 ohm-cm, a thermal expansion coefficient of 35 - 40 in/in x 10-6/°C, a dielectric constant of 3.8, and a tensile strength exceeding 12,000 psi at ambient temperatures. Heat resistant up to 232°C (450°F) , it also withstands chemicals such as inorganic and organic acids, alkalis, organic solvents, and aromatic hydrocarbons.
This epoxy cures at ambient temperature in 48 - 72 hours. Its optimal curing schedule is overnight at room temperature followed by 2 to 3 hours of heat curing at 100°C - 125°C. EP42HT-2ND2MED (Black) has a noncritical mix ratio of 100:40 by weight or 100:50 by volume, and a paste consistency with minimal flow when applied. It offers a working life of 30 to 45 minutes for a mixed 100-gram batch at ambient temperatures, which can be increased by using shallow mixing vessels or mixing smaller batches. Parts A and B for EP42HT-2ND2MED (Black) are available for use in syringes, half pints, pints, quarts, gallons, and five gallon containers.