臺灣博碩士論文加值系統

使用回收料與熔接線的產生現象是塑膠射出成型產業的未來發展趨勢與無法完全避免的重要議題，因此如何掌握回收料的流變特性、射出成型行為與熔接線的性質，將是相關產業需要面臨與克服的挑戰。有鑒於此，本研究利用高速攝影技術與會產生三道次熔接線的可視化模具來直接觀察回收塑料的充填行為與多道次熔接線的形成過程，並採用Moldex3D模擬軟體進行多項製程參數的虛實比對。
首先，本研究選用非結晶性的HIPS材料與半結晶性的PP材料來做實驗，透過毛細管流變儀與Moldex3D MHC擬合方法來獲得回收塑料的黏度模型參數，再將此參數輸入Moldex3D中進行使用，並與實際回收料射出成型與產生多道次熔接線的充填過程進行比較。研究結果顯示，軟體模擬的熔膠流動波前行為與實際射出的結果有不同，因為回收塑料的黏度會明顯低於原料，所以回收塑料的整體射出充填時間會縮減；而塑料回收次數與製程參數對多道次熔接線形成行為也有一些影響。由於熔膠在模腔內的壓力損失現象，促使兩種塑料熔膠在流至模腔末端時，流動阻力增加，所以造成熔接線長度也有逐步增加的現象，即發生在第三道熔接線的長度大於第二道與第一道熔接線長度之情形，在多種製程參數的變動下，都可以發現這個趨勢與現象，而塑料的回收次數的增加會使熔接線長度有明顯的下降。另外，模流分析的結果則顯示出塑料回收次數與製程參數的調變，並不會影響熔接線形成的行為，熔膠波前的變化也不大，模擬結果與實際的回收料射出充填行為和多道次熔接線的形成現象有不同。
對於非結晶性的HIPS材料而言，隨著回收塑料的回收次數增加，確實會導致成品拉伸強度的明顯下降，而且第三道熔接區域的拉伸強度低於第二道與第一道熔接區域的成品拉伸強度，而對於半結晶性的PP材料而言，隨著回收塑料的回收次數增加，其成品拉伸強度只會產生些微的下降，而且第一道與第二道熔接區域的拉伸強度高於第三道熔接區域與沒有熔接區域的成品拉伸強度。最後本研究也進行了材料試片的SEM與DSC分析，以說明各道次熔接區域之拉伸強度變化的可能原因。

The use of recycled materials and the occurrence of weld lines are the future development trend of the plastic injection molding industry and an important issue that cannot be completely avoided. Therefore, how to grasp the rheological properties of recycled materials, injection molding behavior and the properties of weld lines. It will be the related industries that need to face and overcome. In view of this, this research used high speed imaging technology and a visualized mold that would produce three-pass weld lines to directly observe the filling behavior of recycled plastics and the formation process of multi-pass weld lines, and used Moldex3D simulation software to perform virtual and real comparisons of various process parameters.
First of all, this research chooses amorphous HIPS material and semi-crystalline PP material as experiments, and obtains the Cross-WLF model of recycled plastics through capillary rheometer and Moldex3D MHC fitting method, and then inputs these parameters into Moldex3D for further analysis and compared to actual regrind injection molding and filling processes that produce multi-pass weld lines. The research results show that there is a significant difference between the flow front behavior of the melt simulated by the software and the actual injection results, because the viscosity of recycled plastics will be significantly lower than that of raw materials, so the overall injection filling time of recycled plastics will be shortened. The number of plastic recycling and process parameters also have some influence on the behavior of multi-pass weld line formation. Due to the pressure loss phenomenon of the melt in the mold cavity, the flow resistance of the two plastic melts increases when they flow to the end of the mold cavity, so the length of the weld line also gradually increases. That is, the length of the third weld line is greater than the length of the second and first weld lines. This trend and phenomenon can be found under the changes of various process parameters, and the increase in the number of plastic recycling will make the length of weld line decrease obviously. In addition, the results of the mold flow analysis show that the adjustment of plastic recycling times and process parameters will not affect the behavior of weld line formation, and the change of the melt wave front is not significant. It seems impossible to accurately simulate the actual recycled injection filling behavior and the formation of multi-pass weld lines.
For amorphous HIPS materials, as the number of recycled plastics increases, it will indeed lead to a significant decrease in the tensile strength of the product. The tensile strength of the third welding zone is lower than the tensile strength of the second and first welding zone. For semi-crystalline PP materials, as the number of recycled plastics increases, the tensile strength of the product will only decrease slightly. Moreover, the tensile strength of the first and second welding zones is higher than the product tensile strength of the third welding zone and the non-welding zone. Finally, this study also carried out SEM and DSC analysis of the test specimens to explain the possible reasons for the changes in the tensile strength of the welding zones in each pass.

摘要 I
ABSTRACT II
誌謝 IV
目錄 V
圖目錄 VIII
第一章 緒論 1
1-1前言 1
1-1-1塑膠二次料 2
1-1-2熔接線 5
1-2動機與目的 7
1-3論文架構 8
第二章 文獻回顧 8
2-1塑膠回收料 9
2-1-1塑膠回收料結構變化 10
2-1-2塑膠回收料的流動變化 12
2-1-3塑膠回收料機械性質變化 14
2-2熔接線的文獻回顧 17
2-2-1熔接線的形成與熔膠流動變化 17
2-2-2熔接線成品的機械性值分析 19
2-2-3熔接線成品的品質優化 21
2-2-4熔接線形成的可視化研究 22
2-3熔接線行為的CAE模擬 23
2-4文獻總結 26
第三章 實驗材料與設備 27
3-1 實驗材料 27
3-1-1 備製PP與HIPS回收料 27
3-2實驗模具 28
3-2-1產品設計 28
3-2-2模具設計 29
3-2-3模具可視化設計 31
3-3實驗設備 32
3-3-1射出成型周邊設備 32
3-3-2回收料周邊設備 33
3-3-3高速攝影機 33
3-3-4萬能試驗機 33
3-3-5材料流動性能檢測儀 33
3-3-6 模流分析軟體 34
第四章 實驗流程與方法 35
4-1實驗流程 35
4-2實驗規劃 36
4-3射出成型參數規劃 37
4-3-1射出速度與相對黏度實驗 37
4-3-2短射實驗 39
4-3-3成型視窗 41
4-3-4澆口固化實驗 42
4-3-5保壓壓力實驗 43
4-3-6單一參數實驗規劃 45
4-4混煉實驗 45
4-5塑料流動性質量測 46
4-5-1熔融指數量測 46
4-5-2毛細管流變儀量測 46
4-6材料參數擬合 47
4-7射出成型可視化規劃 49
4-7-1可視化拍攝配置 49
4-7-2可視化後處理 49
4-7-3可視化拍攝流程 51
4-8 MOLDEX3D模擬 51
4-8-1 Moldex3D Studio步驟 51
4-8-2材料設定 55
4-8-3模擬參數設定 60
4-8-4計算參數設定 62
4-9拉伸性質量測 63
4-9-1拉伸性質規劃 63
第五章 結果與討論 65
5-1回收料的流動性質與外觀分析 65
5-1-1原料與回收料MI 65
5-1-2原料與回收料黏度變化 66
5-1-3原料與回收料黏度曲線 67
5-1-4回收料外觀變化 69
5-1-5回收料射出成品重量變化 70
5-2模擬與可視化射出結果的數據分析 71
5-2-1模擬與可視化充填時間比對 71
5-2-2回收料流動波前變化 78
5-2-3模擬與實際參數對交匯點距離影響 81
5-2-4模擬與實際參數對熔接線長度影響 94
5-3回收料多道次熔接線拉伸強度分析 107
5-4回收料多道次熔接線SEM與DSC分析 115
5-4-1回收料多道次熔接線SEM分析 115
5-4-2回收料DSC分析 123
第六章 結論與未來展望 126
6-1研究結論 126
6-2未來展望 128
參考文獻 129
附錄一 134
附錄二 146
附錄：作者簡歷 149

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