射出成型為製造業重要的生產過程，技術成熟、成本低且生產快，隨著現行產品追求輕薄短小以及微米奈米級的應用，傳統的射出成型技術也須跟著調整。本研究主要探討影響具微流道之微射出成型元件寬度方向成形之因素，實驗部分分別設計兩副具有微流道之模仁，探討製程參數(模具溫度、保壓壓力)、機械應力以及改變微流道與微流道之間間距對微流道寬度方向尺寸變化之影響。除了實驗部分，本研究還將實驗結果與理論計算做比較，並估測其殘留應力值。且分別利用Moldflow模流分析軟體去計算殘留應力大小及使用壓克力應力應變曲線去反推殘留應力，再將之與理論計算之值做比對。研究結果發現，當微結構之間間距大於2000μm時，製程條件以及機械應力對微結構寬度方向尺寸變化之影響並無明顯趨勢；但當將微結構之間間距縮短至1000μm左右時，因微結構與微結構之間相互影響的關係，應變量有增大的趨勢，且可漸漸看出改變模具溫度對微流道成形之影響。

Micro injection molding is one of the most important processes for making polymer products with micro features. The important prerequisite of the process is the replication accuracy of the micro features in the plastic components, such as DNA/RNA testing fluidic biochips, which are currently in great demand. Most previous studies had investigated the influence of molding conditions on the filling of polymer products with micro features. However, the influence of molding conditions on replication accuracy (shrinkage) has not yet been systematically investigated. An aim of our experiments is to determine the effect of molding conditions (molding temperature, packing pressure, and mechanical force) and geometry (distance between each micro-channel) on replication accuracy of micro polymer parts in detail. The theoretical derivation and simulations conducted via Moldflow® are also used to calculate residual stress.
It was found that when the distance between each micro channel is above 2mm, the replication accuracy only changed slightly with the mold temperature and packing pressure. Furthermore, extending the cooling time did not show significant change in the replication accuracy. Therefore, it could be concluded that the mechanical force during the demolding process is not a crucial effect on the replication accuracy of micro features. Finally, by reducing the distance between each micro channel to around 1mm, the micro channels started to affect each other due to residual stress.

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