This article was first published in the November 2002 edition of Plastics Engineering.
Polyurethane Low-Pressure Balloons
A series of polyurethane films from Polyzen, Inc., featuring film grades that can be thermoformed, are said to provide medical product designers an alternative to latex materials for the construction of low-pressure balloons. The polyurethane films represent a materials source that offers the advantages of research, design, prototyping, manufacturing, and assembly capabilities, with quick turnaround times, and in previously unattainable body-to-neck ratios, according to the company.
Offered in 1:10, 1:15, and 1:20 (and any variation in-between) neck-to-body ratios, the low-pressure balloons can be produced in any size and configuration as small as 0.050 inches. The balloons are fully three-dimensional and exhibit a nearly invisible seam, and they can be produced in thicknesses from 1 to 10 mils. Previously, the configuration of non-latex, low-pressure balloons was limited to two-dimensional form, said to be undesirable and limiting for most medical applications. A special welding process, says Polyzen, allows the polyurethan balloons to be formed into full, three-dimensional shapes. The seams are almost invisible because they are inside the balloon rather than outside, making the devices suitable for in-patient applications. The seam-welding technology ensures that the seams are stronger than the materials used, reports the company.
The line of polyurethane films features film grades that can be thermoformed, the characteristic that makes the material suitable for construction of the low-pressure balloons, says the company. The polyurethane films are expressly offered to medical product manufacturers that require balloons with big bodies and smaller necks in non-latex materials. The balloons can be fabricated in nearly any shape and size, e.g., conical, pear, triangular, and cylindrical. Applications for the Polyzen low-pressure polyurethane balloons include gastrointestinal, vascular, and stomach devices and catheters for drug delivery. Polyzen says all polyurethane films meet Class VI medical applications.
