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ENGEL MUCELL® MICROCELLULAR INJECTION MOLDING

Engel introduces a breakthrough molding process with opportunities and capabilities not possible with other molding processes. MuCell offers new possibilities for innovative product design, optimized processing and reduced part costs.

Mucell technology enables molders to reduce raw material consumption, while producing strong, lightweight products. In addition, the Mucell process allows you to foam materials that cannot be foamed successfully with conventional foaming technologies.

Industries such as automotive, medical devices, consumer goods, electronics, food services, and industrial and consumer structural parts are currently benefitting from MuCell's remarkable advances in microcellular injection molding.

MuCell technology is currently available under worldwide license on new Engel machines. As the first injection molding machine and system manufacturer to license MuCell, we have the the industry's most extensive background working with this technology.

The innovative MuCell microcellular foam process was developed by Trexel, the world leader in microcellular foam technology. Using commercial injection molding equipment in their production-scale test laboratory, Trexel has proven the MuCell process successful on numerous injection molding applications.

The MuCell option can be ordered with a new injection molding machine purchased from Engel world-wide.

MuCell technology offers molders a host of dramatic benefits:

Benefits

• Significant weight savings (up to 50%)

 • Reduction of 30-50% in clamp tonnage
• Reduction of material viscosity • Reduction or elimination of hold time

• Significant reduction in process temperature
(up to 78°C, 140°F)

 • Reduction in overall cycle time
• Reduction of 30-50% in hydraulic injection pressure • Eliminates sink marks in the end product
Results may vary depending on the application.

The MuCell® Process
The MuCell microcellular foam process uses supercritical fluids (SCFs) from atmospheric gases to create evenly distributed, uniformly sized microscopic cells throughout the polymer. The MuCell process works without chemical blowing agents (CBAs), hydrocarbon-based physical blowing agents, nucleating agents, or reactive components. MuCell can handle a wider range of melt indexes than conventional foaming processes.

The MuCell process has been implemented successfully with a broad range of injection molded thermoplastic polymers – including acetal, liquid crystalline polymers (LCPs), polyamide, PA6 and PA6/6, polycarbonate (PC), polycarbonate /acrylonitrile butadiene styrene (PC/ABS), polyethylene (PE), polytherimides (PEIs), polypropylene (PP), high-temperature sulfones -- as well as TPEs such as Santoprene, Kraton, Dynaflex, and TPUs such as Elastollan.
Four Basic Steps
1. Gas Dissolution. A supercritical fluid (SCF) from an atomospheric gas (CO2 or N2) is injected directly into the polymer through injectors installed in the barrel to form a single-phase solution. The SCF delivery system's screw and injectors are designed specifically to facilitate the rapid dissolution of the SCF in the polymer.
2. Nucleation. A large number of nucleation sites (orders of magnitude greater than with conventional foaming processes) are formed throughout the polymer during the molding process. A substantial and rapid pressure drop is necessary to create the large number of uniform sites.
3. Cell Growth. Cell growth is controlled by processing conditions. Precise control of pressure and temperature is achieved through specifically designed Engel machine control hardware and software.
4. Shaping. After injection into the mold, part shape is controlled by the mold design. Although mold modifications are not required, in some cases modifications will optimize the benefits of MuCell.
® MuCell is a registered trademark of Trexel, Inc.
® MuCell is a registered trademark of  Trexcel.

Value-Added Features

A MuCell®-equipped Engel gives you all the benefits of the microcellular foam process along with the unbeatable competitive advantages of an Engel injection molding machine.

The processing software -- running on our powerful 32-bit RISC-based machine controller -- has been specifically modified to optimize control of the MuCell process. In addition, a MuCell-equipped Engel can run in both solid and MuCell modes of operation.

Engel Tiebarless Molding with MuCell®

 Engel-designed MuCell control package
MuCell-designed plasticizing assembly
Air-cooled heater bands
Supercritical fluid (SCF) control valves
Supercritical fluid (SCF) dispensing unit

Engel Tiebarless injection molding offers even greater advantages when combined with MuCell technology. The MuCell process makes it possible to operate at lower clamp tonnages because it dramatically lowers injection pressures compared to conventional molding. The unique Engel Tiebarless gives you greater usable platen surface, letting you run a physically larger mold in a smaller tonnage machine -- an added benefit for microcellular foam injection molding.

But the advantages of the Engel Tiebarless don't stop there. Tiebarless molding offers quicker, easier mold mounting and faster, simpler part handling automation. And Engel's evolved tiebarless clamp technology has been proven around the world in more than 11,000 applications.