臺灣博碩士論文加值系統

在纖維素材研究領域中，再生纖維素一直被認為具有相當潛力，主要因為此種纖維之製造材料係採用再生資源---木漿纖維素為原料，然而由於傳統纖維素溶解的製程方法主要採用黏膠法，此法相當複雜，加工過程中只要稍微不當將生產出不同特性的成品，所以在加工過程中須嚴密監控，以免過量之副產物形成而影響纖維之性質。另外由於環保意識抬頭，立法對廢氣、廢水管制愈來愈嚴格，使得傳統黏膠法生產之成本提高。近年來在歐美發展出溶劑法製造纖維素纖維，此法除無黏膠法之環境與成本的缺點，更有高溶劑回收率、污染性低、成品物性佳之特點，文獻顯示溶劑法仍有纖維素聚合度衰減及膠液黏度大等等缺點，若能改善上述缺點，並解決溶劑成本過高，提高回收率及加強纖維物性，必可在商業化路上更向前邁進。本實驗主要針對前述問題研究纖維素在NMMO/H2O溶劑法系統下，其膨潤效應，並以真空烘箱進行溶解之試驗。之後再進行薄膜之製作，並探討其物化性質的變化（如聚合度、強度、透明度等等），並經由高效能液相層析儀來偵測溶劑之濃度，及探討溶劑是否因製程中受高溫，而使溶劑產生裂解變化，最後在溶劑回收、純化及濃縮過程中探討溶劑回收之效率。 而研究結果顯示，在膨潤的研究部分，則是以添加微量的氫 氧化鈉調配NMMO/H2O溶劑，pH值為11時為最佳之膨潤狀況。但 是在膨潤時以均質機攪拌，由於轉速過快且剪切力過大，同時溫 度上升過高，導致於纖維聚合度衰減與溶劑裂解變黃。而在以真 空烘箱溶解纖維素時，可達到18.23％的高溶解度。根據文獻上記 載此濃度已有可能達到液晶高分子的狀態。而回收液以高效能液 相層析儀之偵測結果，是有部分之NMMO以裂解成NMM，但是 這部份可由添加雙氧水進行氧化NMM反應，故可達到相當高的回 收率。

With the past twenty years, considerable effort has been directed toward finding simple, nonderivatizing solvents for cellulose. It is anticipated that this will lead to new cellulosic products of improved properties. Several broad reviews of cellulose solvents have been previously published. However, we are particularly interested in those that have been proven to dissolved cellulose without formation of a derivative during dissolution. The NMMO/H2O system has been given the greatest attention. The cellulose products from NMMO/H2O are known as Lyocell which has been claimed as green product for twenty-first century. In this report, we are concentrated on the study of those interaction behavior between cellulose and solvent. Preferably, most of the result were obtained on the NMMO/H2O solvent system.According to the studies, an improved method of making cellulose dope made up of NMMO/H2O solvents with added sodium hydroxide and other additives. Also, we had reach a 18.23 wt.％cellulose in drop, which may show a liquid crystalline behavior. The cost and efficiency of cellulose direct solvent system were calculated from the recovery of solvent. These results showed a 99％solvent recovery which could make a commercialized film process possibly in the future.