• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.351-351
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• 2006

The possible interactions between cyclodextrins and biodegradable polyesters were investigated. The hydrophobicity of cyclodextrin could be varied with the methyl substitution of host CD, and the possibility of IC formation and the types of interaction between respective CDs and polyesters were subsequently changed. Further, the effect of cyclodextrins on the morphological change of biodegradable polymer was shown to depend on the degree of IC formation between cyclodextrin and biodegradable polymer as well as on the type of interaction between respective CDs and polyesters. That is, the enhancement and/or the restriction of the crystallization of P(3HB) were observed by the incorporation of various kind of cyclodextrins with different cavity size and hydrophobicity.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 가을 학술발표회 논문집
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• pp.209-210
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• 2003

The durability and anti-microbial stability of plastics, which have been thought to be favorable characteristics, cause ecoloical problems due to non-degradation after disposal. For a possible solution of these ecological and environmental problems, the biodegradable polymers. especially aliphatic polyesters, have been widely investigated. Poly(tetramethylene succinate)(PTMS) is one of the most promising biodegradable polyesters. (omitted)

• 폴리머
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• 제29권3호
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• pp.314-319
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• 2005

촉매인 stannous octeate 존재 하에서 글리콜리드를 이관능성 개시제인 1,4-butanediol, 1,6-hexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol과 반응시켜 4가지 종류의 새로운 지방족 디올을 합성하였다. 이들 새로운 디올과 succinic acid, adipic acid, 혹은 suberic acid와 titanium(IV) isopropoxide 촉매하에서 170, 190, 또는 $220^{circ}C$에서 축합중합 시켜 분자구조가 규칙적으로 배열된 새로운 지방족 폴리에스테르와 무질서한 구조를 갖는 폴리에스테르를 각각 얻었다. 이들 지방족 폴리에스테르들의 유리전이온도($T_g$)는 -40에서 $30^{circ}C$ 사이였다. 또한 $170^{circ}C$에서 제조된 분자구조가 규칙적으로 배열된 폴리에스테르가 높은 온도에서 합성된 구조가 무질서한 폴리에스테르들보다 $T_g$가 $5-10^{circ}C$ 정도 높았다. 체외분해 실험 결과, 분자구조가 규칙적으로 배열된 폴리에스테르가 불규칙한 중합체보다 완충용액 속에서 가수분해속도가 느렸다.

• 공업화학
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• 제3권3호
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• pp.377-385
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• 1992

• Bulletin of the Korean Chemical Society
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• 제19권6호
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• pp.680-685
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• 1998

Two kinds of new aliphatic diols were synthesized by the ring-opening reaction of lactide and glycolide with 1,4-butanediol, a difunctional initiator, in the presence of stannous octoate. The resulting aliphatic diols were melt-polymerized with D-tartaric acid at 150 ℃ to produce new crosslinkable polyesters. They were reacted with hexamethylene diisocyanate in THF at 65 ℃ in a teflon mold for 24 h to prepare sequentially ordered crosslinked polyesters (BD/LT/GL/D-tartarate). Degradation of the prepared yellow crosslinked films was carried out in a buffer solution in order to examine the effect of time, pH, temperature and crosslinking degree on their degradation rate and mechanism. The rate of degradation increased with an increase in pH and temperature, but it decreased with increasing degree of crosslinkage incorporated into the crosslinked polyesters. We also found that the crosslinked polymers were converted into the acidic compounds such as lactic, glycolic, and D-tartaric acids during the degradation.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1997년도 춘계학술발표회 논문집
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• pp.328-332
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• 1997

Hot stretching focused on the improvement of properties of poly(L-lactic acid) fiber. Some aliphatic polyesters are biodegradable under microbial attack and the new unique applications are expected. Generally, these materials have a somewhat low melting temperature and low mechanical properties compared with the aromatic polyesters. In this study, melt-spinning of poly(L-lactic acid) was conducted. We investigated effects of the stretching and the molecular orientation of aliphatic polyester fibers on the change of fine-structure. Glass transition temperature, molecular orientation and crystallinity increased according to the increase of stretching ratio.

• 대한의용생체공학회:의공학회지
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• 제16권1호
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• pp.9-16
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• 1995

Biodegradable poly (I ,4-butanediol succinate) (PBS) was synthesized from 1,4-butanediol and succinic anhydride. The glass transition temperature of poly (I, 4-butanediol succinate) was revealed at $73^{\circ}C$. The crystallization and cold crystallization of the polymers were investigated as a function of holding time in melt state, cooling rate. reheating, and molecular weight. Chain scission and/or cmsslinking did not occur in the melt state at var.ious holding times. Slower scanning rate can allow more times for nucleation, rearrangement, and packing of the polymer chain, so the onset temperature of crystallization from the melt was increased. PBS crystallized from the melt was found to have spherulitic structure. The degradation behavior of PBS was studied under basic conditions and with microorganisms using the modified ASTM method. In the basic solution. PBS lost up to 85% of its mass within two days. Based upon visual observation, the crystalline structure of films composed of larger molecular weight polymers retained their crystallinity longer than similar structures in low molecular weight samples.

• 청정기술
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• 제8권4호
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• pp.223-228
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• 2002

다양한 화학구조를 포함하는 폴리에스테르를 분해성 수지인 셀룰로오스와 비분해성 수지인 PVC 및 PE를 기준물질로 한 controlled compost test와 soil burial test를 적용하여 생분해 거동을 살펴보았다. 이들 고분자의 화학구조가 유연한 지방족 사슬과 에스테르기를 가지고 있는 지방족 폴리에스테르는 가수분해 효소에 의해 분해되고, 방향족 고리를 포함하는 공중합 형태의 폴리에스테르는 상대적으로 낮은 생분해도를 보여주었다. 조절된 퇴비화 조건에서 셀룰로오스가 45일에 70.6%의 분해도를 보일 때, 합성된 poly(butylene adipate-co-succinate), poly(butylene succinate), poly(butylene adipate-co-succinate-co-terephthalate)는 각각 44.0%, 32.0%, 23.4%,의 생분해도를 보여주어 이들 고분자의 화학적 구조에 따라 생분해거동이 많은 영향을 받음을 확인하였다.

• 한국고분자학회지:고분자과학과기술
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• 제18권5호
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• pp.436-443
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• 2007

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.357-357
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• 2006

Many industrial sources of proteins can be used as raw materials to produce films, molded materials, and various hollow items either by "casting" techniques or by "thermoplastic processing". Combining proteins with natural fibbers, paper or biodegradable polyesters is very promising to form biodegradable composites witch take advantage of the barrier and mechanical properties of each component. Using nano-fillers to form nanocomposites has also been shown to be interesting to improve properties. Production, with low transformation cost, of protein based materials to form biodegradable materials with controlled functional properties for food uses, medical uses, packaging, agriculture, controlled release systems, etc. is discussed.