利用分子動力學研究不同結構之高分子對 玻璃轉換溫度與動力學性質的影響

Studies of Polymer Dynamics Properties and Glass Transition Temperature with Different Structures by Molecular Dynamics Simulation

蔡瑞鴻(Ruei-Hong Tsai)

指導教授 ： 李佳翰

國立臺灣大學/工學院/工程科學及海洋工程學研究所/碩士(2018年)

https://doi.org/10.6342/NTU201804063

摘要

隨著材料科學的進展，藉由混合不同材料來提升其性質的方法越來越多樣化。因為高分子材料通常擁有優異的熱力學性質，可以彌補其他材料的在這方面的缺陷，使得高分子材料的應用範圍越來越廣。利用材料模擬科學與現今優異的計算機性能，可以快速且經濟的去預測多種高分子的性質。本論文將利用分子動力學探討多種不同結構的高分子，計算其熱力學性質、動力學性質與高分子結構參數，並從中歸納高分子結構與這些參數之間的關係，比較不同高分子結構動力學參數與熱力學參數對於玻璃轉移溫度的差異。發現PEO如文獻提到玻璃轉移溫度利用熱力學性質取值較接近實驗值，但PMMA、PAM則無此現象。

關鍵字

分子動力學 ； 玻璃轉移溫度 ； 高分子迴旋半徑 ； 高分子均方位移 ； 擴散係數 ； 高分子豫弛時間

並列摘要

As the progress of materials science, the methods by mixing different materials to enhance their properties are more and more diversification. Because polymer materials usually possess excellent thermodynamic properties, which can make up for the defects of other materials in this aspect, and making the application of polymer materials more and more extensive. Nowadays, using material science simulation and excellent computer performance, can be quickly and economically to predict the properties of various polymers. In this thesis, the thermodynamic properties, dynamics properties, and structural properties of polymers will be calculated, and we will discuss variety polymers with different structures by molecular dynamics. Finally, we compare glass transition temperature by results of the dynamic parameters and thermodynamic parameters, and sum up the relationship between these parameters and polymers. It was found that PEO mentioned in the literature that the glass transition temperature is close to the experimental value by thermodynamic properties, but PMMA and PAM do not.

並列關鍵字

molecular dynamics ； glass transition temperature ； radius of gyration ； mean square displacement ； diffusion coefficient ； relaxation time

參考文獻

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