Chitosan 과 Alginic Acid 를 이용한 캡슬형 비료 및 제초제의 투과특성 = The Permeability of Capsule Type Fertilizer and Herbicide with Chitosan and Alginic Acid

다국어 초록 (Multilingual Abstract)

Effects of the concentration of NaCl, the concentration and the molecular weight of chitosan on the permeability of capsule type fertilizer and herbicide were investigated. The encapsulating process was based on the electrostatic interaction between chitosan(a polycationic polymer) and sodium alginate(an anionic polysaccharide). Sodium alginate solution(1%) was dropped into chitosan solution(1 %) in which various amounts of NaCl was added. The capsule strength was increased with the addition of NaCl and the maximum value of capsule strength was observed at 0.3M NaCl. Capsule type fertilizer and herbicide were immersed in deionized water to determine its permeability, and it was affected by the concentration of NaCl and chitosan, and the molecular weight of chitosan. As the concentration of NaCl in chitosan solution increased, permeability of the capsule increased and marked the maximum value of 88%(fertilizer), 87%(herbicide) at 0.75M NaCl. As concentration of chitosan solution increased, permeability tended to decreased; it showed the maximum value of 90%(fertilizer) and 90.3%(herbicide) at 0.25% chitosan and the minimum value of 83%(fertilizer) and 82%(herbicide) at 1% chitosan. Permeability of fertilizer and herbicide also decreased, as the molecular weight of chitosan(material of capsule) was decreased; it was showed 86%(fertilizer) and 83%(herbicide) at M.W. 330,000(sonication time Omin) and 52%(fertilizer) and 51%(herbicide) at M.W. 119,000(sonication time 180min). The chitosan-alginic acid capsule was manufactured(defined as prepared capsule), dried for 6hrs and immersed in deionized water(defined as restored capsule) to examine restoration of capsule. Restoration of capsule was good, and capsule strength was slightly decreased form 20g/cm2(prepared capsule) to 17g/cm2(restored capsule).