以分子動力學研究高分子溶液之結構性質與奈米噴流行為

Abstract

軟性電子具有可塑性、重量輕、耐衝擊等優點，潛藏龐大的商機。製程上透過噴印技術將導電性材料「印刷」於基材上，因此微尺度的噴墨列印製程技術受到各界的重視。此外印刷製程也可以運用於電子元件構裝上，倘若能達到奈米尺度的噴印，電子元件的發展也將進入一個新的次元。本文藉由分子動力學模擬研究高分子溶液奈米噴流技術，透過不同的操作條件觀察噴流過程，選用的高分子噴流材料為聚氧乙烯溶液，採用EA model進行模擬，透過結構簡單、應用甚廣的水溶性聚氧乙烯幫助瞭解高分子溶液的噴流過程。金屬勢能則選擇Morse potential 來使用，水分子則使用Simple point-charge (SPC/Fw) model 進行模擬，相較於其他水分子模型，由於在性質方面的再現性與實驗結果相當一致，同時是水分子模型中最簡單的三質心點類型，擁有較佳的計算效率，適合運用在大尺度的加工模擬的研究。 研究的過程分為二個階段：建立高分子溶液，討論溶液結構並驗證模擬之程式的正確性；隨後選用合適的金原子建立噴嘴，建立噴流裝置模型；本研究著重於驅動力的影響，研究不同的推擠溶液的速度對噴流之行為造 成的影響。

Duo to plasticity, light weight, impact resistance and other advantages, flexible electronics have the huge potential business opportunities .Micro scale jet printing technology will play an important role since the conductive material can be printed on a substrate via this printing process .In addition , the printing process can also be applied to the packaging of electronic components. If the jet printing process can achieve nanometer scale, the development of electronic components will also enter a new territory .In this study a nano-jet printing technology with a polymer solution as a printing material was investigated using molecular dynamics and then observed the jet printing process by varying the operating conditions. Due to its simple structure and wide usage, the polyethylene oxide was utilized as a printing material to simulate and to understand the jet printing process, using explicit atoms model (EA) .Morse potential was chose to represent a potential model for the metal with regards to the water molecule. Simple point-charge (SPC/Fw) model was used to be a potential model, due to the reproducibility and consistency in the experimental results for the properties of water. Meanwhile, this SPC/Fw model is the simplest three-sites model which possesses better computational efficiency, consequently leading to be suitably applied to the investigation for the large scale processing simulation. The process of this study was divided into two steps. The first step was establish the polymer solution and then discussed the structure solution and identifies the correctness of the simulation program. Second step was to choose a proper metal atom to construct a nozzle and to establish a model for the system of jet flow. Finally, this study aimed to investigate the effect of driving force and to study the effect of plunger speed on the behavior of jet flow.