海藻酸鈉合成纖維素水凝膠之控釋應用

Controlled-Release Application of Sodium Alginate Based Cellulose Hydrogel

姚青瑋(Ching-Wei Yao)

指導教授 ： 柯淳涵

國立臺灣大學/生物資源暨農學院/森林環境暨資源學系/碩士(2023年)

https://doi.org/10.6342/NTU202303118

摘要

本實驗主要以海藻酸鈉作為基材，添加羧甲基纖維素作為增強材料，目的是研發一種天然物聚合水凝膠，以提高肥料的緩釋效果和土壤的保水性能。在實驗過程中，探討了兩種合成變因：一是調整海藻酸鈉與纖維素的比例，包括2:1、1:1和1:2三種比例，以探討原材料量對產物性能的影響；二是固定海藻酸鈉的份量，調整羧甲基纖維素的比例，以研究纖維素對於產物性能的改變，包含1:0到1:5。
在肥料緩釋效果方面，測定了氮肥和磷肥的含量的釋放量。比較不同合成條件下水凝膠的緩釋效果，包括在水中的釋放和在土壤中的釋放。同時，還對水凝膠的保水性能進行了測試，以評估其對土壤吸水能力的影響。
結果表明，使用水凝膠可以有效地緩慢釋放肥料，氮肥和磷肥的趨勢相同，纖維素在本實驗作為吸收與釋放的關鍵材料，在閾值前都呈現越多越好的趨勢。此外，保水性試驗也證實了水凝膠對土壤吸水能力的提升作用，同樣在樣品破裂前都能具有最好的保水效果。綜上所述，本研究提出的天然物聚合水凝膠具有應用潛力，可作為一種綠色肥料緩釋劑和土壤改良劑，對於推廣可持續農業具有重要的意義。

關鍵字

海藻酸鈉水凝膠 ； 纖維素水凝膠 ； 控制釋放 ； 農業緩釋 ； 土壤保水性

並列摘要

Objective of this study is to develop a natural-based polymer hydrogel using sodium alginate as the base material and incorporating carboxymethyl cellulose as a reinforcing agent. The goal is to enhance the controlled-release ability for fertilizers and to improve soil water retention capacity. Two parameters were investigated: the first is to adjust the ratio of sodium alginate to carboxymethyl cellulose, with three ratios of 2:1, 1:1, and 1:2; the second is to change the amount of carboxymethyl cellulose, ranging from 1:0 to 1:5 with constant amount of sodium alginate.
The results indicate that the hydrogel effectively reduce the release rate of nitrogen and phosphorus fertilizers. Carboxymethyl cellulose, a key material for absorption and release in this study, demonstrated a positive correlation with the amount of hydrogel. Furthermore, the water retention test also confirmed the hydrogel's ability to enhance soil water absorption. The synthesized hydrogel was able to maintain excellent water retention until the point of rupture. In conclusion, the natural-based hydrogel synthesized in this study demonstrated great potential as a green controlled-release agent for fertilizer and soil conditioner. It could contribute significantly for sustainable agriculture.

並列關鍵字

Sodium alginate hydrogel ； Cellulose hydrogel ； Controlled-release ； Agricultural slow-release ； Soil water retention

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