• Archives of Pharmacal Research
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• 제9권2호
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• pp.63-73
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• 1986

The use of biodegradable polymetric materials as drug carriers is a relatively new dimension in polymeric drug delivery systems. A number of biodegradable or bioerodible polymers, such as poly(lactic/glycolic acid) copolymer, poly($\alpha$-amino acid), polyanhydride, and poly (ortho ester) are currently being investigated for this purpose. These polymers are useful for matrix and reservoir-type delivery devices. In addition, when chemical functional groups are introduced to the biodegradable polymer backdone, such as poly (N-(2-hydroxypropyl) methacrylamide), the therapeutic agent can be covalently bound directly or via spacer to the backbone polymer. These polymer/drug conjugates represent another new dimension in biodegradable polymeric drug delivery systems. In addition, examples of biodegradable polymeric durg delivery systems currently being investigated will be discussed for the purpose of demonstrarting the potential importance of this new field.

• Journal of Pharmaceutical Investigation
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• 제25권3호
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• pp.223-226
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• 1995

A new method to study water uptake into biodegradable polymer was developed. Polymer was gently mixed with the tritiated buffer and the radioactivity level of the polymer due to water uptake was measured by liquid scintillation counting. The rate of water uptake was estimated from the plot of the amount of water in the device as a function of time. The technique used in this study is particularly useful for estimating water uptake of biodegradable polymers which were difficult to study by other techniques such as weight gain used for hydrogel.

• Journal of Pharmaceutical Investigation
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• 제30권4호
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• pp.295-297
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• 2000

A new method to evaluate erosion of biodegradable polymer, polyanhydrides, was developed. The polymer devices were prepared with the melt-casting method and weight loss was accurately measured after agitating the devices in buffers (pH 1-9), and removing the device at selected time intervals and freeze-drying the device. The erosion rate was estimated from the plot of the weight loss(%) of device as a function of time. The freeze-drying technique used in this study is particularly useful for estimating the erosion rate of biodegradable polymer.

• 한국고분자학회지:고분자과학과기술
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• 제10권2호
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• pp.224-234
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• 1999

• 펄프종이기술
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• 제43권2호
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• pp.49-56
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• 2011

Mulching technique is used to control the temperature and moisture content of soil by covering the ground surface. Most kinds of mulching film are made of polyethylene which is non-biodegradable synthetic polymer. Utilizing these films has been one of the main sources in soil pollution. Thus residual films under the ground should be removed after a certain period of time. Therefore, an alternative mulching material made of biodegradable functional paper is considered instead of non-biodegradable films. The mulching sheet produced from paper basis has a functionality to be naturally degraded and then recycled to the bio-materials on soil. In this study, the paper based-mulching sheet coated with biodegradable polymer was specially produced using a laboratory bar coater. Coating colors prepared by dissolving PBS/PLA in chloroform were applied to kraft paper. The mechanical strength and aging properties of this mulching sheet were investigated. The burst strength of polymer-coated paper was decreased with the increase of the PBS ratio in PBS/PLA blends, and, in particular, 30/70 blending condition led to good stability in heat-aging atmosphere for 60 days.

• 펄프종이기술
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• 제45권2호
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• pp.13-20
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• 2013

In this study, two biodegradable polymer(PLA, PBS) emulsions were treated on agricultural packaging paper such as fruit bagging paper. Water-repellency, mechanical properties, and SEM image with thermal aging were measured on the emulsion treated fruit bagging paper. Biodegradable polymers(such as poly lactic acid, poly butylene succinate) emulsion treated fruit bagging paper had higher water-repellency and strength than other water-repellent(such as acrylic repellent, linseed oil and paraffin wax) treated fruit bagging paper. According to FE-SEM results of polymer emulsion coated fruit bagging paper, the colloidal particles of emulsion after thermal treatment (looks like being) were adhered to the fibers. Thus, using biodegradable polymer emulsion is expected to protect a fruit for a long time.

• 펄프종이기술
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• 제42권2호
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• pp.75-81
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• 2010

Characteristics of mixing biodegradable polymers and polymer impregnated paper for mulching mat for seedling were investigated. The mixed film of 70% PLA was most easily biodegradable. The surface of polymer films were changed to more rough due to enzymatic degradation of lipase. Tensile strength and breaking elongation of PLA mixed films were increased to the 0.04-0.31 kN/m and the 0.17-0.96%, respectively. With higher PLA contents, intensities of ester originated carboxyl group(about $1,748cm^{-1}$) were increased. Physical properties of prepared mulching mats were increased with PLA contents and stiffness of mulching mat was not so much changed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.374-375
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• 2006

The purpose of this paper is to investigate the propriety of biodegradable polymer pad in spite of exchanging from existing polyurethane pad used in CMP(Chemical Mechanical Planarization). Poli 400 of G&P Technology for CMP and Ellipsometer of Rudolph AutoEL-III for measurement were used in this experiment. From this experiment, it is proven that the biodegradable polymer pad is sufficiently suitable in CMP process. Therefore, it is expected that, by using the biodegrable pad CMP manufacturing process, and will be decreased. Especially, wafer scratch can be decreased.

• Korean Chemical Engineering Research
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• 제58권1호
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• pp.36-43
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• 2020

생분해성 금속인 마그네슘 합금 와이어를 이용하여 담관용 스텐트를 제작하였다. 생체 내에서 마그네슘 합금의 문제점인 빠른 분해 및 부식을 제어하기 위하여 마그네슘 합금 와이어를 생분해성 고분자인 polycaprolactone (PCL), poly(propylene carbonate) (PPC), poly(L-lactic acid) (PLLA), poly(D,L-lactide-co-glycolide) (PLGA) 등으로 코팅하였다. 표면분해가 이루어지는 고분자인 PPC의 경우는 전분해 거동을 보이는 다른 고분자들(PCL, PLLA, PLGA)에 비해 크랙이나 박리가 없어 가장 효율적으로 마그네슘 와이어의 분해 속도를 지연시켰다. 또한 생분해성 고분자 코팅이 마그네슘 합금 스텐트의 기계적 물성인 축 방향 힘에 미치는 영향에 대하여 조사하였다. 대부분의 생분해성 고분자(PCL, PLLA, PLGA)로 코팅된 스텐트는 코팅되지 않은 스텐트에 비해 축 방향의 힘이 증가하여 스텐트의 유연성을 감소시켰으나, PPC로 코팅된 스텐트는 코팅되지 않은 스텐트와 비슷한 축 방향의 힘을 나타내 스텐트의 유연성을 감소시키지 않았다. 이상의 결과로부터 PPC가 가장 효율적인 생분해성 고분자로 판단된다.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.179-179
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• 2006

PLGA/HA composite scaffold fabricated by GF/PL method showed enhanced mechanical property, hydrophilicity and osteoconductivity compared with the SC/PL scaffolds, and this enhancement was most likely due to a higher extent of exposure of HA particles to the scaffold surface. The biodegradable polymer/bioceramic composite scaffolds fabricated by the GF/PL method could enhance bone regeneration efficacy for the treatment of bone defects compared with conventional composite scaffolds.