The reporter recently learned from Xu Jingyi, the technical director of Engel Machinery Corporation, which specializes in injection microbubble forming machines in the United States, that the injection microbubble forming technology developed by the Massachusetts Institute of Technology has completed the transition from the laboratory to the industrialization. Will be very optimistic.
Microbubble injection molding technology is a new injection molding technology. By forming a large number of tiny cells (100 micrometers or 50 micrometers or less) in the interior of the product, it can reduce the amount of plastic and make the product obtain special properties. Moreover, it can shorten the molding cycle by improving the thermodynamic mechanism of the process. The injection of microbubbles does not require holding pressure, which greatly reduces the clamping force and eliminates the residual stress in the workpieces, and ultimately eliminates surface depressions.
The disadvantage of general microbubble injection molding is that the surface quality of the article is not as good as non-foaming parts, and the tensile strength is also reduced. Developed by the Massachusetts Institute of Technology and licensed by Trexel for gas back pressure injection and mold rapid heating and cooling technology, the quality of the surface of the workpiece is well solved. Therefore, the injection of microbubbles is more advantageous in applications where high-precision, thin-walled, large-planar, non-warped parts are required, or in situations where the flow-length ratio is large, resulting in mold-filling difficulties and the tonnage of the mold being too low. The advantages of injection micro-bubble molding technology is that it can save the amount of plastic, and the product has the characteristics of buffer, sound insulation, heat insulation and flexibility.
Xu Jingyi said that injection of microbubbles using carbon dioxide and nitrogen inert gas as a foaming agent does not pollute the environment. Coupled with its weight savings and unique material properties and dimensional stability, it is a promising new injection technology. Since 1998, Trexel and Engel have cooperated in the trial production of the first reciprocating screw microbubble special injection machine. To date, there are more than 200 MuCell microbubble injection molding machines in the world, half of which are distributed in Asian countries. However, the current high cost of technology introduction and the application complexity of the technology make it an obstacle to the promotion and application in China.
Xu Jingyi said that if domestic companies are interested in adopting this technology, joint development will be a reliable and economical way.
Source: China Chemical News