Fabrication of Micro-Structured Polymer by Micro Injection Molding Based on Precise Micro-Ground Mold Core.

Yanjun Lu,Fumin Chen,Xiaoyu Wu,Liejun Li,Yan Lou,Chaolan Zhou

doi:10.3390/mi10040253

Yanjun Lu, Fumin Chen + Show 4 more

Open Access

https://doi.org/10.3390/mi10040253

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Abstract

Precise micro-grinding machining was proposed to fabricate regular and controllable micro-grooved array structures on the surface of mold cores to realize the mass production and manufacturing of micro-structured polymer components by micro injection molding in this paper. First, the 3D topographies and section profiles of micro-ground mold cores and micro-formed polymers with different micro-structure parameters were presented. Then, the surface roughness of mold cores and polymers were compared. Next, the relationships between machining accuracy of mold core ground by micro-grinding and filling rates of micro-structured polymer formed by micro injection molding were investigated. Finally, the influences of micro injection molding parameters on the filling rate of micro-structures polymer were investigated. It is shown that the micro-structured polymer can be effectively and rapidly fabricated using the proposed method. The experimental results indicate the highest form accuracy of the micro-grooved mold core and the filling rate of micro-structured polymer can reach to 4.05 µm and 99.30%, respectively. It is found that the filling rate of the micro-structured polymer roughly increased with increasing machining accuracy of the mold core. The injection pressure had the greatest influence on the filling rate of the injection formed polymer, while the melt temperature had the least influence.

Highlights

Micro-structured polymer components have been widely used in many fields, such as optics, biomedicine, electron and microelectro-mechanical systems (MEMS), etc. [1,2,3]
It had been confirmed that the micro injection molding was an alternative to the mass production and manufacturing of micro-structured polymer products due to its short molding cycle, high efficiency, and low production cost [6,7]
An amorphous polymer surface with high aspect ratio micro-structures had been fabricated by micro injection molding for application in bio-MEMS for erythrocytes depletion [9]

Summary

Introduction

Micro-structured polymer components have been widely used in many fields, such as optics, biomedicine, electron and microelectro-mechanical systems (MEMS), etc. [1,2,3]. The superhydrophobic polymer surfaces with hierarchical micro-nano cylinder array structures were successfully fabricated by micro injection molding [8]. It was found that a dressed super-abrasive diamond grinding wheel may perform precision micro-grinding for mold core to obtain smooth micro-structured surface [15,16,17].

Results

Conclusion