New low-pressure moulding materials protect devices from a range of environmental issues
Henkel has introduced three new low-pressure moulding (LPM) materials designed to seal and protect medical devices from moisture, temperature extremes, chemicals, vibration, impact and other environmental concerns.
“Using a gentle, low-pressure process, Loctite PA 6732, Loctite PA 6682 and Loctite PA 6951 completely encapsulate medical devices, including catheters, tube sets, connectors and surgical tools, as well as sensors and switches used in medical diagnostic and monitoring equipment,” states Henkel.
All three LPM products are tested to Henkel’s protocols, based upon ISO 10993 biocompatibility standards, including skin sensitisation, with certificates available on request.
Hot melts replace thermoplastic housings
“LPM hot melts completely replace thermoplastic housings and allow manufacturers to produce complex and intricate assemblies by customising part geometry, surface texture, colour and opacity,” adds the company.
These materials form an adhesive bond with the entire component being encapsulated, becoming part of the component’s three-dimensional form and creating a water-tight, chemically-resistant seal. The cost-effective LPM process involves three steps: placing the bare component into a custom mould set, heating the polyamide material and injecting it at low pressure into the mould, and allowing the material to cool rapidly for 10 to 50 seconds before removing the newly encased and bonded component for immediate use.
Green and sustainable
Formulated to allow greater design freedom than traditional medical encapsulants, Loctite PA 6732, Loctite PA 6682 and Loctite PA 6951 are single-component, solvent-free polyamides that are solid at room temperature. Derived from natural fatty acid feed stocks obtained from renewable resources, such as soy, rapeseed and sunflowers, they are green and sustainable. "No harmful fumes are released during the moulding process, and all products are RoHS and REACH compliant," confirms Henkel.
Loctite PA 6732 is an amber material that performs well in temperatures from -40 to 140°C. Clear Loctite PA 6682 is designed for use in temperatures between -25 and 105°C. Loctite PA 6951 is a colourless material that performs well in temperatures from -40 to 100°C.
These new products are part of Henkel’s complete portfolio of LPM products used in electronic components, power and industrial automation, HVAC and lighting applications.