Injection molding enables large-scale production of polymer and plastic materials with micrometer-sized features. Now, A*STAR scientists have developed a method for creating mold templates with high precision and few defects.
A fluid behaves very differently when it is confined to micrometer-scale channels. This phenomenon already has several applications such as enabling the analysis of small samples of blood.
These microfluidic systems are small and portable, easy to use without expert knowledge, and disposable because they are cheap to produce. But this disposability means that microfluidic chips need to be quickly mass-produced.
Now, Jiang Guo and his colleagues from the A*STAR Singapore Institute of Manufacturing Technology have developed a method for fabricating molds that can quickly create microfluidic channels in polymer substrates. “The technology addresses a critical problem in mold insert fabrication for microfluidic chip production, and will enhance local industry,” says Guo.
Injection molding involves shaping a material while in a molten state using a metal template. It is cheap, fast, and useful for creating microfluidic chips. However, engineering a mold with precise micrometer-scale features and smooth surfaces is challenging as burrs and tool marks create defects. A post-polishing process can fix some of these imperfections, but it is difficult for polishing tools to access the recessed corners of microstructured surfaces and remove unwanted material uniformly.
thumbnail courtesy of phys.org