| 摘要: | 本研究針對半結晶性材料聚丙烯與非結晶性材料聚苯乙烯為基材，添加放熱型發泡劑(偶氮二甲酰胺)後利用射出成型做出樣本，並搭配Moldex3D模流分析軟體進行短射結果驗證。製程中針對射速、預塑量、料溫、模溫、發泡劑量設定三因子水準做一次一因子實驗，並利用效果分析篩選顯著因子進行田口法規劃，最後使用回歸分析法與S/N分析法分析結果與比較。
實驗結果觀察巨觀現象如 : 重量、比重、膨脹倍率來觀察發泡效率，以及微觀現象如 : 電子顯微鏡觀測氣泡密度及尺寸，綜合考量放熱型發泡劑的最佳參數，最後比較兩種材料的最佳參數在膨脹倍率的表現，結果顯示半結晶性材料因結晶關係較不易發泡，PP在低射速、高料溫、低模溫有最佳的膨脹倍率，而PS在高射速、中等料溫、低模溫有最佳的膨脹倍率。
針對本實驗而言，一次一因子法與田口規劃法所得參數趨勢相同，又利用一次一因子法所得之實驗與時間成本較低，因此射出實驗使用一次一因子法作實驗規劃較佳；利用回歸分析與S/N分析法所得結果相同，因此判斷使用S/N分析法可快速簡易得到參數趨勢。
;In this study, the semi-crystalline material polypropylene and the amorphous material polystyrene were used as the substrate. The exothermic foaming agent (azodicarbonamide) was added to the substrate to make samples used in injection molding experiments. After experiments done, using Moldex3D mold flow analysis software verified flow-length results gotten from short shot experiments. In our experiments, we used one-factor one-time experimental design to carry out for the three-factor level of five parameters such as: injection speed, shot size, melt temperature, mold temperature and amount of CBA. Therefore, the effect factor analysis was used to choose the significant factors for the Taguchi experimental design. Finally, regression analysis method and S/N analysis method were used to analyze the trend of parameters and then compare each ways’ pros and cons.
We observe the experimental results from macroscopic phenomena such as: weight, specific weight, and expansion ratio to find better foaming efficiency, and microscopic phenomena such as: electron microscopy (SEM) to calculate bubble density and size. Taking great consideration of the optimal parameters and setting these parameters to redo experiment, finally compare two materials in expansion ratio. The results show that the semi-crystalline material is less likely to foam due to the crystallization
phenomenon. PP has the best expansion ratio at low rate of injection speed, high melt temperature and low mold temperature, while PS is high rate of injection speed, medium melt temperature, and low mold temperature have the best expansion ratio.
For this experiment, the trend of the parameters obtained by the one-factor one-time experimental design and the Taguchi experimental design is the same, and the experiment and time cost obtained by the experimental design are lower. Therefore, the one-factor one-time experimental design for the injection experiment is better for experimental design. The results are the same as that obtained by the regression analysis method and S/N analysis method, so it is concluded that the parameter trend can be quickly and easily obtained by using the S/N analysis method. |
