• 한국미생물·생명공학회지
• /
• 제24권5호
• /
• pp.546-552
• /
• 1996

The applicability of chitosan, a biodegradable natural polymer, as the coating material to prevent the dispersal of the spores of the apple white rot agent Botryosphaeria dothidea, was investigated. The physical properties of mixed chitosan/polyvinyl alcohol(PVA) film showed the increased physical properties for film formation, such as tensil strength, elongation, and viscosity, compared to either chitosan or PVA film. The FT-IR spectra of chitosan/PVA film indicated that the film was formed by simple blending not by any new synthetic bond. The chitosan and chitosan/PVA film showed effective antifungal activity on B. dothidea. The formed films were well decomposed by ASTM strains used for biodegradability test, on the other hand, the PVA film could not be decomposed by above standard strains. The field test at apple orchard showed that the dispersal of B. dothidea spores could be effectively reduced by coated film, especially by chitosan/PVA film. The spore dispersal was reduced upto 97.0% by 1.0% chitosan/5.0% PVA film during 4 months.

• 한국환경보건학회지
• /
• 제24권3호
• /
• pp.48-53
• /
• 1998

Chitin is known as biodegradable natural polymer. But, in spite of various application of chitin from waste marine sources, commercial use of chitin has been limited due to highly resistance to chemicals and the absense of proper solvents. We made various viscosity of chitosan from chitin by change of Mima's method through the deacetylation which is various condition of NaOH concentration, reaction time and temperature. Also, Polyvinyl alcohol/chitosan blend films were prepared by different solution blends containing the ratio of 5, 10, 15 and 20% chitosan and low, medium, high molecular weight of chitosan to find a more useful biodegradable polymer. Thermal and mechanical properties of PVA/chitosan blend films such as DSC, impact strength, tensile strength and morphological changes by SEM were determined. The 10-15% PVA/chitosan(low, medium) blend films were similar to PVA. Also, PVA/chitosan blend films at the laboratory soil test(Pot Test) were completely degraded in month with four kinds of soils by microorganisms.

• 한국식품영양과학회지
• /
• 제28권2호
• /
• pp.417-422
• /
• 1999

Algin and chitosan are known as biodegradable natural polymers. PVA is useful for the production of water soluble packaging, paper, textile sizes. PVA/Algin and PVA/chitosan films were prepared by solution blends method in the weight ratio of chitosan, algin for the purpose of useful biodegradable films. Thermal and mechanical properties of blend films such as DSC, impact strength, tensile strength and morphology by SEM were determined. As a result, The ratio of 10.0wt% PVA/chitosan films were similar to PVA at thermal and mechanical properties. PVA/Algin films were found that phase separation was occured as more than 25wt% increasing the blend ratio of algin. PVA/Algin films were observed to be less partially compatibility than 10wt% increasing the blend ratio of algin by DSC, mechanical properties and SEM. Blend films were completely degraded pH 4.0 better than 7.0, 10.0 in the buffer solution. Also, they were rapidly degraded in the enzyme( glucosidase) solution better than pH solution by enzymolysis.

• 폴리머
• /
• 제27권5호
• /
• pp.405-412
• /
• 2003

수용성 고분자인 폴리(비닐 알코올) (PVA)과 키토산에 제 4급 암모늄염을 도입하여 합성한 수용성 키토산 유도체인 N-(2-하이드록시)프로필-3-트리메틸 키토산 클로라이드 (HTCC)를 수용액 상태로 하여 용액 블렌딩하고 이를 캐스팅하여 PVA/HTCC 블렌드 필름을 제조한 후 두 고분자 사이의 혼화성과 블렌드 필름의 특성을 FT-IR, DSC, DMA 및 TGA를 사용하여 검토하였다. HTCC 함량을 50%까지 변화시킨 본 연구의 혼합 범위에서 블렌드 필름들은 모두 투명한 상태를 나타내었으며, T$_{g}$와 T$_{m}$ 이 하나로 나타나 두 고분자 사이에 혼화성이 있음을 확인하였다. 또, HTCC의 우수한 항미생물성 때문에 HTCC가 1%만 포함되더라도 블렌드 필름은 우수한 항미생물성을 나타내었다.

• Fibers and Polymers
• /
• 제6권2호
• /
• pp.174-179
• /
• 2005

The present paper studies the effect of chitosan, cationic starch and polyvinyl alcohol (PVA) as sizing agents to enhance surface properties of kenaf paper. The polymers were incorporated into the sheets by spray application. The results clearly showed that the addition of chitosan to a sheet formed from beaten fibers had excellent improvement in surface properties, compared to the effect of other additives. Sizing quality of cationic starch fairly matched with the sizing quality of chitosan, however, it was able to reduce the water absorption potential of paper more than chitosan at a same concentration. In most other properties, particularly the most important property for printing papers, surface smoothness, chitosan-sized papers are superior to the paper sized with cationic starch or PVA.

• 폴리머
• /
• 제28권3호
• /
• pp.253-262
• /
• 2004

독성이 없고 생분해성과 생체적합성을 가지는 폴리(비닐 알코올)/키토산 블렌드 필름들은 용액상태로 캐스팅 하여 제조하였다. 블렌드 필름들의 물리화학적 특성들의 변화는 여러 가지의 분석방법을 통해 조사하였다. 항균특성의 고찰에서 키토산이 10 wt% 이상 함유된 모든 블렌드 필름의 정균율은 99.9%로 우수하게 나타났다. 수분율은 키토산의 함량이 증가함에 따라 증가하나 팽윤도는 감소하였다. 키토산 함량이 15 wt% 내에서는 블렌드 필름의 용융온도와 결정화온도가 키토산의 함량에 따라 증가하였다. 또한, 키토산이 10, 15 wt% 함유된 블렌드 필름들은 용융온도가 각각 229와 228$^{\circ}C$로 순수 PVA보다 높은 값을 나타내었다. 그러나 키토산 함량이 20 wt% 이상일 경우 용융온도는 감소하였다. 블렌드 필름의 역학적 특성들은 습윤상태 및 건조상태 모두 키토산 함량이 증가함에 따라 증가한다 키토산 함량이 15 wt% 내에서 높은 인장강도를 나타낸다.

• 한국섬유공학회:학술대회논문집
• /
• 한국섬유공학회 2003년도 봄 학술발표회 논문집
• /
• pp.321-322
• /
• 2003

Poly(vinyl alcohol) (PVA) is a polymeric biomaterial that obtained by the saponification of poly(vinyl acetate) (PVAc). It has a nontoxic and water-soluble synthetic polymer, and has excellent biodegradability, biocompatibility, ability of film forming, and hydrophilic property, which is widely used in biochemical and biomedical applications.$\^$1)/ Chitosan is one of a few natural cationic polysaccharides that can be obtaiend by alkaline deacetylation of chitin which is the second most abundant polymeric material in the earth.$\^$2)/ (omitted)