聚乳酸(polylactic acid, PLA)是無毒、並具良好生醫可降解特性及生醫相容性的聚酯類高分子。其可廣泛使用於生醫元件及其他應用。本研究主要探討聚乳酸高分子於熱壓轉印過程中，製程程序及參數對材料性質及成形特性的影響。
實驗利用維克氏硬度計、萬能材料試驗機、凝膠滲透層析儀(GPC)、示差掃描熱量分析儀(DSC)等設備，探討各種不同熱壓製程參數對材料性質的影響。實驗結果發現隨著熱壓溫度與熱壓時間增加，材料之楊氏係數逐漸變大，但斷裂伸長率反而變小，導致材料過於脆化。實驗結果發現將熱壓溫度控制於70℃到110℃之間、熱壓時間控制在4分鐘內，可獲得較理想的斷裂伸長率。未來以此熱壓轉印製程參數製作生醫元件，應可得到較佳的元件機械性質及材料特性。
本研究進一步使用微/奈米結構模仁熱壓轉印成形聚乳酸高分子材料，並利用田口方法找出較佳之製程參數。分析結果指出脫模溫度40℃、熱壓溫度110℃、熱壓壓力9MPa、熱壓時間60s為較佳之製程參數。此結果與初始製程參數之轉寫率相比，可從79.9%提升至96.3%，不僅大幅的改善產品品質，並且也減少製程時間。

Polylactide (PLA) is a widely used polymer for biomedical devices which has received much attention because of its originating from renewable resources and its potential biodegradability. The primary objective of this study was to measure the material and forming properties of PLA at hot embossing process.
The properties of the PLA material have been investigated with different imprint temperature and imprint time by micro hardness tester, material test machine, gel permeation chromatograph (GPC), differential scanning calorimeter (DSC) and X-ray diffraction (XRD). As the results shown, if the imprint temperature or imprint time increases more, the mechanical properties may change significantly. The results show that this phenomenon mainly occurs due to the crystallization. However, the results show that if we control the imprint temperature between 70oC to 110 oC, imprint time within 3 minute, a good elongation at break will be obtained.
In addition, the forming characters of PLA micro/nano structure with nanoimprint technology are studied by Taguchi method. According to experimental results the transfer rate has been improved from 79.9% to 96.3% with process parameters of demolding temperature 40oC, imprint temperature 110oC, imprint pressure 9MPa and imprint time 60s. The results show that this process can reduce the experiment and manufacturing time. This study will contribute to the biomedical devices fabrication with biodegradable polymers by hot embossing process.

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