• Polymer(Korea)
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• v.31 no.3
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• pp.233-238
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• 2007

The purpose of the study is to apply composites of poly (glycolic acid) (PGA) with [poly(R) 3-hydroxybutyrate] (P3HB) or poly (butylenes succinate- co-L-lactate) (PBSL) as medical resorbable composite materials with the complement of hydrolysis rate of each component. As a result, it was confirmed that the PBSL/PGA and P3HB/PGA composite fiber were hydrolyzed in phosphate buffer solution. Also, it has been revealed that the degradation of PBSL/PGA are accelerated due to PGA producing glycolic acid which can act as a catalyst. In addition, the hydrolysis of PBSL/PGA was found to be accelerated by the presence of lipase PS. When the PBSL/PGA composite fiber was placed in the air, not much hydrolysis has proceeded. Also, it was confirmed that the P3HB/PGA composite fiber maintained proper tensile strength in the air. Therefore, these complex fibers can be adapted to use as environmentally suitable, medically absorbable composite materials.

• Journal of Digital Convergence
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• v.17 no.11
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• pp.467-474
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• 2019

Key areas of digital contents, the games and animation industries are increasingly expanding. Therefore, training of a specialized workforce is required in accordance with these enterprises' growing demand. Education in the field of games and animation lies in cultivating talents with creative thinking, collaboration, and problem-solving skills. Thus, this paper aims to propose a PBSL teaching model for creative convergent talent through game and animation projects. The study will focus on the characteristics of creative convergence talents, project teaching, and related job competencies for game and animation education. Based on literature research, a 'Project Based Self Learning' instructional model is presented, in which creative thinking and collaboration competencies are explained in a way they can be performed by the learner. As a case study, D University's class was applied with PBSL. A survey showed that the autonomy aspects were higher than the creativity and convergence attitudes, indicating that the students improved their autonomy and motivation. However, the team composition needs further supplementation.

• Polymer(Korea)
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• v.31 no.3
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• pp.228-232
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• 2007

This purpose of this study is to enhance the hydrolysis of poly (butylene succinate-co-L-lactate) (PBSL) and poly [(R) -3-hydroxybutylate] (PHB), to develop materials with advanced medical absorbability and environmental suitability. The first method involves increasing the bioabsorbability of poly (glycolic acid) (PGA) in the core of the fibrous complex, while the second method involves making a complex fiber containing PBSL and PHB in the outer layer for improving environmental degradability Improvement in the hydrolysis of PBSL and PHB due to glycolic acid occurs by hydrolytic behavior of PGA. The drawing supporting the resulting PBSL/PGA fiber was executed at $65^{\circ}C$, where the orientation is well arranged in crystal form. Obtaining a PHB/PGA complex fiber in the proper crystal orientation at $50^{\circ}C$ was not possible since the arranged crystal orientation was only identified in drawings from temperatures above $50^{\circ}C$. Also, it is necessary to execute a smooth surface to achieve an on-line drawing since unevenness occurs in the fibrous surface from an in-line drawing.

• Korean Journal of Poultry Science
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• v.28 no.2
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• pp.91-98
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• 2001

Three experiments were conducted to investigate the Pine Bark Spent Liquor (PBSL) inclusion, prepared by alkaline sulfite-anthraquinone cooking, on Pellet durability index (PDI) of practical diets and performance of broiler chicks and laying hens. Fourteen treatments with four replications were assigned for PDI test in Experiment 1. Control, 10% Wheat(W10), 20% Wheat(W20), 0.25, 0.50, 1.00, 2.00 and 3.00% PBSL, 0.1, 0.2% commercial pellet binder A(CPB A) or B(CPB B), W10 plus 0.1% CPB A or B were used for PDI test. PDI was measured by PDI tester (Oriental Motors, Japan). The control diet was based on corn and soybean meal with no wheat or pellet binders inclusion. The PDI of the PBSL or other commercial pellet binder treatments were significantly higher than control groups(P<0.05). It was shown 95.9, 95.9, 95.8, and 95.7 in W10, 0.5% PBSL, 0.2% CPB A or B treatments, respectively. Thus, those treatments were applied to Experiments 2 and 3. In experiment 2, 200 male broiler chicks (Cobb$\times$Cobb) were allocated to the control, W10, PBSL 0.5%, 0.2% CPB A and B with four replications. Starter diets contained 3,169, 3,149 kcal/kg ME and 21% CP, and finisher diets were fed at the level of 3,192, 3,172 kcal/kg ME and 19W% CP. Weight gain, feed intake, feed conversion ratio (FCR) were weekly measured for 5 wk and the number of intestinal anaerobes were examined at the end of experiment. The weight gain of chicks fed PBSL was not significantly greater than control groups, but was significant different compared to that of W10 or 0.2% CPB A treatments (P<0.05). FCR of chicks treated with PBSL or other pellet binders tended to improve compared to that of control.

• Macromolecular Research
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• v.16 no.7
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• pp.651-658
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• 2008

Poly(butylene succiate) (PBS), poly(butylene succinate-co-L-lactate) (PBSL), and poly(butylene succinate-co-6-hydroxycaproate) (PBSCL) polymers were degraded by lipase $PS^{(R)}$, and the enzymatic degradation mechanism of PBS was analyzed in detail. The enzymatic degradation of PBS gave 4-hydroxybutyl succinate (4HBS) as the main product. An exo-type hydrolysis mechanism was proposed based on this observation. The terminal chain of PBS had conformational similarity to ordinary tri- and diglycerides and could be incorporated as a substrate in the active site of this lipase. The surface adsorption of the lipase was much larger on PBS and its copolymer films than on the other polyester films because the lipase adhered quite strongly to the polymer terminal through a specific adsorption mechanism. Kinetic analysis showed that the total number of surface adsorption points per unit area of PBSL and PBSCL copolymers was larger than that of the PBS homopolymer.