• 한국잠사곤충학회지
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• 제43권1호
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• pp.41-48
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• 2001

The purification, dissolution and powdering of stained waste silk obtained from weaving and dyeing process were studied for the surface modification of textile fabric and plastic materials. The whiteness of stained waste silk could be improved through degumming and bleaching with sodium hydrosulfite. The water-soluble fibroin solution can be obtained by dissoving the degummed waste silk in a boiling solution of 50% calcium chloride for 60 minutes. The salts and heavy metals contained in fibroin solution were removed by electric dialysis, wool fiber filtration and gel filtration chromatography. The fibroin powder was prepared by using a fine grinder after the alkali treatment for weakening the silk fiber. The fine fibroin powder of particle size around 30 ㎛ was obtained with a ultra fine-mill, while it was finer below 10 ㎛ with a ball-mill. The dissolved or powdered silk was applied to the surface of fabric with addition of the binder (a urethane resin). The moisture content of polyester and nylon fabrics treated with the silk solution was improved due to hygroscopic property of silk. The fine fibroin powder mixed with the binder ws coated on the surface of synthetic film by use of the air pressed sprayer. It was revealed that the hygroscopicity as well as the softness of fibroin powder coated film was much improved. Therefore, it is thought that the fine silk fibroin powder is applicable as an coating agent for the surface modification of plastic and synthetic leather.

• International Journal of Industrial Entomology and Biomaterials
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• 제20권2호
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• pp.99-105
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• 2010

In this paper, the regenerated silk fibroins were dissolved in LiBr aqueous solution with different dissolution temperature and time, and the effects of the dissolution condition on the regeneration yield, molecular weight, wet spinnability, and electrospinnability of regenerated silk fibroin were investigated. The regeneration yield, molecular weight distribution, and wet spinnability of regenerated silk fibroin were nearly affected by the dissolution temperature and time. However, the electrospinning performance of silk fibroin was influenced by the dissolution condition implying the electrospinning of silk fibroin is more sensitive process than the wet spinning in the range tested in this study. While $25^{\circ}C$ of dissolution temperature resulted in a good electrospinnability of regenerated silk fibroin, the electrospinnability was slightly deteriorated when silk fibroin was dissolved at $60^{\circ}C$ for 6 hours. Also, though the fiber diameters of electrospun silk fibroin produced by the dissolution at $25^{\circ}C$ for 6 hours and 24 hours were 443 and 451 nm, respectively, that at $60^{\circ}C$ for 5 min was reduced to 411 nm. The fiber diameter was more decreased to 393 nm when the dissolution time increased up to 6 hours at $60^{\circ}C$.

• Fibers and Polymers
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• 제2권2호
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• pp.58-63
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• 2001

Silk fibroin (SF) was dissolved in calcium chloride/ethanol/water mixture(1/2/8 in mole ratio) at $70^{\circ}C$ for 4h. The dissolved silk fibroin was regenerated by casting the dialyzed solution into films. The films were treated with 50% aqueous solution of methanol for different times, and their antithrombogenicity was evaluated by in vivo tests. In vivo blood tests were made by a method of peripheral vein indwelling suture. It was found that the silk fibroin had a good antithrombogenicity and an absorbability even though the polymer showed foreign body reaction. Finally, the blood compatibilty of silk fibroin films which were subjected to structural change by the methoanl treatment, was examined in connection with their interfacial surface energy, and a correlation between these properties was found to be present.

• 한국잠사곤충학회지
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• 제45권2호
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• pp.121-125
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• 2003

Dissolution of Antheraea pernyi silk fiber was carried out in a zinc nitrate 6 hydrate (Zn(NO$_3$)$_2$ㆍ6$H_2O$) solution with various dissolving conditions. The solubility was significantly dependent on the concentration of zinc nitrate, dissolving temperature and time. Regenerated A. pernyi silk fibroin powder was obtained through dialysis process to remove chaotropic salt. FTIR and X-ray diffractometer showed that the conformation of regenerated A. pernyi silk powder was sheet structure.

• 한국잠사곤충학회지
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• 제18권1호
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• pp.21-26
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• 1976

각종 고치의 견층부위별 fibroin 효소분해율의 차이 및 견사물성과의 관계를 구명코자 시험하여 다음과 같은 결과를 얻었다. 1. 각종 고치의 견층부위별 fibroin 효소분해율은 외층에서 내층으로 갈수록 높았다. 2. 이상용견의 견층부위별 fibroin 분해율은 정상견에 비하여 높았으며 옥견＞박피견＞사용견＞정견 순위를 보이었다. 3. 원종인 잠111과 잠112의 fibroin 분해율 및 sericin 함유량은 교유종인 잠 111$\times$잠112보다 높았다. 4. 인공사료육잠견의 견층부위별 fibroin의 분해율은 외층보다 내층으로 갈수록 증가되었으며 sericin 함양은 외층에서 내층으로 갈수록 감소되었으나 최내층에서 약간 증가되는 경향을 보이었다. 5. 견층부위별 연편사의 절단강력은 외층에서 내층으로 갈수록 감소되는 경향이었고 이상용견의 절단강역은 정견에 비하여 저하되었다. 6. 견층부위별 fibroin 분해율과 견사의 절단강력과는 부의 상관(${\gamma}$=－0.8)이 인정되고 그 회귀방정식은 y= －0.29x＋5.07 이었다.

• International Journal of Industrial Entomology and Biomaterials
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• 제21권1호
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• pp.145-150
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• 2010

The regenerated silk fibroin with various molecular weights (MW) was prepared by different dissolution condition and the effect of coagulant on the wet spinnability of the various MW silk fibroin solutions dissolved in formic acid was investigated by the observation of wet spun filament in coagulant and the measurement of maximum draw ratio. The observation on the wet spun filament in coagulation bath revealed that good fibers without bead were formed in a high MW and a very high MW silk fibroin samples. In contrast, beads were observed in the silk fibroin sample with medium MW. The maximum draw ratio of wet spun silk fibroin filament decreased with MW reduction. The decrease of maximum draw ratio in isopropanol, acetone, DMF and THF was remarkably higher than that in methanol and ethanol, indicating that the coagulant type strongly influenced the wet spinnability. The two simple evaluation methods used in this study showed complementary information for wet spinnability: (a) The observation of filament in coagulant was effective to check a continuous fiber formation and a bead formation, and (b) the maximum draw ratio measurement was useful to examine the post drawing ability related to molecular orientation.

• 한국잠사곤충학회지
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• 제42권2호
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• pp.109-113
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• 2000

The preparation of skin care gauze could be make to mixing separated cellulose from waste milk pack and degummed silk fibroin fiber. Also, its wound covering and anti-bacterial activity were investigated in order to find out the enhancement of their functionality. By the 30% silk fibroin fiber including skin care gauze, the anti-bacterial activity values of Staphylococcus strain are much 4 times higher than of 0∼10% silk fibroin fiber including skin care gauze. The average yield of cellulose from waste milk pack was obtained 50-60%, and their morphologies, physical properties, modulus and biodegradation ratios are studies, respectively.

• 한국잠사곤충학회지
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• 제39권1호
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• pp.73-78
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• 1997

분자량 약 7000의 Fcp는 효소분해역반응을 이용하는 것에 의해 분자량 약 17000과 약 24000까지 고분자량화된 PIFcp가 얻어졌다. 또, 효소분해의 역반응에 의해 고분자량화되는 것은 일부의 Fcp이며 Silk II형결정으로부터 Silk I형결정으로 전이하는 것은 대부분의 Fcp에서 나타났다. 이 PIFcp는 X선회절과 시차열분석(DTA)의 결과로부터 어느정도 안정한 Silk I형의 결정구조를 가지는 것이 확인되었다.

• 한국염색가공학회지
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• 제6권3호
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• pp.60-66
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• 1994

With the view of studying on the dual adsorption mechanism of acid dyes in connection with the structural difference of silk fibroin, silk fiber and silk fibroin memberane were used for equilibrium dyeing at $60^{\circ}C$, $70^{\circ}C$, $80^{\circ}C$ and pH 3.2, pH 5.0. The dyes used were C.I.Acid Orange 7 and C.I.Acid Red 88 introduced aromatic hydrocabon into Acid Orange 7. From the adsorption isotherm experiment, the total uptake of dyes can be described by Langmuir sorption and Nernst partition. Nernst partition. Nernst partition coefficient $K_1$ decrease of crystalline regions and orientation. The saturation value S of Acid Red 88 were large than total amino group contents and it was attributed it hydrophobic bond. On the other hand, the standard afficity and enthalpy were increased with the in crease of hydrophobic part of dyes. Both $k_1$ and $K_2$ were decreased with the increase of pH, but $k_2$ were more effected than $K_1$.

• International Journal of Industrial Entomology and Biomaterials
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• 제45권2호
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• pp.70-77
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• 2022

Wet-spun regenerated silk fibroin (RSF) fibers have been extensively studied owing to their 1) useful properties as biomaterials, including good blood compatibility and cyto-compatibility; 2) the various methods available to control the structural characteristics and morphology of the fiber, and 3) the possibility of fabricating blended fibers and new material-embedded fibers. In this study, silk nanofibrils prepared using a new method were embedded in RSF to fabricate wet-spun silk nanofibril/RSF composite fibers. Up to 2% addition of silk nanofibril, the silk nanofibril/RSF dope solution showed slight shear thinning, and the G' and G" of the dope solution were similar. However, above 3% silk nanofibril content, the viscosity of the dope solution significantly increased. In addition, shear thinning was remarkably evident, and the G' of the dope solution was much higher than the G", indicating a very elastic state. As the silk nanofibril content was increased, the wet-spun silk nanofibril/RSF composite fiber became uneven, with a rough surface, and more beaded fibers were produced. Scanning electron microscopy observations revealed that the beaded fibers were attributed to the inhomogeneous dispersion and presence of agglomerates of the silk nanofibrils. As the silk nanofibril content and RSF concentration increased, the maximum draw ratio decreased, indicating the deterioration of the wet spinnability and post-drawing performance of silk nanofibril/RSF.