|A Study on the Property Modification Analysis and Process Parameter Optimization Design of Polylactic Acid Composite Materials
|C. F. Kuo, W. L. Lan, C. C. Fang
郭中豐, 藍偉倫, 方建洲
|This study discussed two types of biodegradable polymer composites (polylactic acid and polybutylene succinate). UV absorbers and hindered amine light stabilizers were added to prolong the life cycle of the composite fibers in outdoor lighting conditions. By using the multi-objective optimization theory, this study examined the impact of the composite mixing process and melt spinning process on the product quality in different stages.
This study divided the planning into two stages. The first stage was “The polylactic acid composite exploitation”. The aim was to discuss the impact of different material proportions, dual-screw process parameters on the mechanical strength of polylactic acid composite. Moreover, this study explored major properties of polylactic acid composite, such as the photo-degradation, the thermal properties, material compatibility, melting flowability and weather resistance. Compared with pure PLA, the results suggested that, Taguchi method and the principal component analysis can improve the bending strength by 27%, the tensile strength by 13.47% and the impact strength by 22.95%. Finally, after 480 h of UV aging acceleration test, the tensile strength retention rate was 94.86%, which was higher than the pure polylactic acid by 44%. The break extension retention rate was 85.17%, which was higher than the pure polylactic acid by 35.17%.
The second stage was “The polylactic acid composite fiber process parameters design”. The aim was to obtain the as-formed fiber by melt spinning method from the polylactic acid composite. The impacts of spinning temperature, spinneret rotation speed, take-up speed on the as-formed fiber quality in the fiber spinning process were also discussed. The response surface methodology was applied to establish the regression models of different quality characteristics before using the multi-objective particle swarm algorithm for the optimization processing of these quality characteristic models and parameter constraints. The experiments found that the polylactic acid/polyacid butanediol ester composite material was better than the polylactic acid/polycaprolactone composite material. The optimal composite fiber compared with PCL composite, the fiber strength was 1.69(gf/d) with an improvement by 42% and elongation at break was 176.04% with an improvement by 27%.
本研究係結合兩種生物可降解性高分子聚乳酸(Poly Lactic Acid, PLA)及聚丁二酸丁二醇酯(Poly(butylene succinate), PBS)之複合材料，並添加紫外線吸收劑(UV-absorbers)及受阻胺光穩定劑(Hindered amine light stabilizers, HALS)延長複合材料於戶外光照下之生命週期，並結合多目標最佳化理論探討此複合材料混煉製程及熔融紡絲法加工製程對不同階段產物品質之影響。 本研究開發分為二階段，第一階段為光穩定性PLA複合材料開發，探討材料複合比例及雙螺桿混煉製程參數對PLA複合材料機械強度之影響，並探討複合材料之光降解性質、熱性質及材料相容性。結果顯示，應用田口法結合主成份分析法(Principal component analysis, PCA)，相較於純PLA可降低彎曲強度27%、提升拉伸強度13.47%及衝擊強度22.95%，且經過480小時紫外線降解測試，其拉伸強度及斷裂伸長率之保留率高達94.86%及85.17%，分別較純PLA高出44%及35.17%。 第二階段為PLA複合材料纖維製程之參數設計，將PLA複合材料透過熔融紡絲法取得初生纖維，探討其製程中紡絲溫度、紡嘴轉速及捲取速率對纖維品質特性之影響，利用反應曲面法(Response surface methodology, RSM)建立其迴歸模型，結合多目標粒子群演算法(Particle swarm optimization, PSO)針對模型及製程參數做最佳化處理，顯示最佳化之複合材料之纖維強度相較於同為生物可分解材料之聚己內酯(Polycaprolactone, PCL)複合材料提升42%及斷裂伸長率提升27%。
|polylactic acid, polybutylene succinate, composite, melt spinning
24.3 | 24.4
24.5 | 24.6
24.7 | 24.8
23.3 | 23.4
23.5 | 23.6
23.7 | 23.8
22.3 | 22.4
20.3 | 20.4
19.3 | 19.4