A New Idea In Magnetic Stirrers -- Sandwich Protected NdFeB Cores For Vigorous Stirring In Any Shape
V&P Scientific is proud to introduce our new VP 772F and VP 772T series of PTFE encased Neodymium Iron Boron NdFeB Magnetic Stirring elements. Neodymium is the strongest of the permanent magnetic materials but you haven¡¯t seen it offered as a magnetic stirrer as the temperature required by the PTFE encapsulating process destroys the magnetic characteristics of Neodymium (NdFeB). Without a way to protect the Neodymium from the solution to be stirred and without a barrier to prevent leaching of the NdFeB into the solution it was not possible to use Neodymium as a stir device.

V&P has solved that problem with our new "Sandwich" technique for encasing the neodymium in protective layers of PTFE and Parylene (patent pending). This ability allows us to produce very powerful Neodymium (48 MGO) stir bars and other shapes that are now capable of greater coupling to the drive magnet and thereby achieving higher stirring speeds for a more rapid mixing action and the stirring of extremely viscous solutions. This is a proprietary process and V&P is the only source of PTFE protected neodymium stir elements.

Another advantage of this process is that it is very easy to make custom shapes to fit specific applications. You don¡¯t have to search for a stirrer that will fit your vessel - just tell us the shape and length you need and we will make it for you in less than 2 weeks.

Still yet another advantage of this system is that you can use either NdFeB or the more temperature resistant SmCo magnetic dscs. So in applications where you want to stir and heat the reaction mixture between 150C and 300C, you should select the SmCo drive magnets. NdFeB highest operating temperature is 150C and SmCo is 300C.

VP 772F Series

The VP 772F series is a new concept in magnetic stirrers. The VP 772F features pairs of parylene encapsulated NdFeB or SmCo magnetic discs with a 1.58 mm thick pocketed sheet of PTFE sandwiched in between (Patent Pending). An N in the part number indicates that the discs are NdFeB and an S indicates SmCo.

The PTFE sheet can be made to any shape to accommodate the internal dimensions of any vessel as illustrated in the photo to the right. Multiple pockets to accommodate multiple magnetic discs are also possible as indicated in the photo. All these stirrers were designed to be small enough (width) to fit through the neck of the bottle and long enough to cover the internal diameter of the bottle for maximum surface contact. When placed on a VP 708 Vortex Lateral Tumble Stirrer the flat shape of the VP 772F stands up on edge and becomes a "paddle" capable of moving large volumes of liquid with ease. These stir elements can also be used with conventional horizontal magnetic stirrers.