Papers by Keyword: Silk

Abstract: In this study, Chitosan-Xyloglucan encapsulated Titanium dioxide was prepared by in-situ method for coating Silk fabric. FT-IR XRD characterized the functional groups and formation of crystallization of composite film. SEM analysis showed the immobilization of composite film on the surface of silk fabric. The coated silk fabrics were stained with methylene blue, and the stain removal efficiency was evaluated. The results showed that the composite film was deposited onto the silk fabric. The functional groups showed peaks around 1635 to 1636 and 400 to 500 cm^-1 that indicate the presence of C=N groups of Chitosan-Xyloglucan and Ti-O groups of TiO₂ on the composite, respectively. The XRD results indicated that the TiO₂ prepared by the sol-gel method was an anatase crystalline structure. The mechanical properties showed the composite film was superior to the Chitosan-Xyloglucan, TiO₂, and uncoated silk fabric. Finally, the methylene blue degradation capability was investigated. The coated silk fabric has insignificantly removing methylene blue stain than the untreated silk fabric, but it is noticeably repellent to stain.

Abstract: In this study, a combined aroma finishing and pigment printing process was investigated in order to develop 1-step, all-in aroma finishing/pigment printing process for Thai silk. Lemongrass oil microcapsules, an aroma finishing agent, was applied on silk by screen printing process and the properties of the printed fabrics were examined. Pigment printing was also performed individually by screen printing and the colorimetric properties of the print were measured. Binder content affected the print properties of both aroma microcapsules and pigment on silk. An appropriate binder content was chosen at 20 g/100 g print paste. The 1-step, all-in aroma finishing/pigment printing process was performed by printing both lemongrass oil microcapsules and pigment simultaneously on silk fabrics. The process efficiency was determined in two different aspects i.e. aroma finishing effect and coloring effect. Aroma finishing effect of the 1-step, all-in process was examined in comparison with the individual microcapsule print results while the coloring effect was compared between the printed fabric from 1-step, all-in process and the individual pigment printing. The results showed that the 1-step, all-in process could provide comparable aroma finishing effect and pigment print quality to the separated finishing and pigment printing processes.

Abstract: Plasma technology provides an effective way to modify the surface of polymeric materials and thus improve the physicochemical properties of this material. This study was a preliminary study in exploring the application of plasma technology in the surface modification of silk fiber. Experimental results revealed that the dyeability of silk fabric with acid dye was improved after plasma treatment.

Abstract: Plasma technology is an effective way to modify the physicochemical properties of silk fabric. This study was a preliminary study to explore the dyeability of silk fabric with metal complex dyes after treated with plasma technology, which may improve the processability and broaden the application of silk fabric. This study investigated the optimal plasma treatment condition and evaluated treated silk fabric in terms of wettability, surface modification and dyeability. It was found that plasma treatment can enhance the wettability and dyeability of silk fabric via the formation of hydrophilic functional groups in the structure of silk fiber.

Abstract: The incorporation of protein based polymeric materials with calcium phosphate (CaP) coatings can provide excellent biological characteristics and biocompatibility with its bone-like protein-CaP composition. Calcium chloride-ethanol catalysed hydrolysis reaction and wet precipitation method was used to prepare silk solution and to precipitate brushite respectively to produce the brushite/silk composite powder. FTIR analyses showed that brushite absorption bands were prominent, overlapping the less intense N-H bands in silk. The most distinct absorptions from the silk were N-H bands. 1g of silk additive to the 300 ml of solution media resulted in arbitrary particle attachment onto brushite crystal surface; most of the brushite particles were covered by the silk β-sheets phase.

Abstract: Natural indigo dye was applied on silk fabric by using pad-batch and pad-dry techniques in the present of thiourea dioxide and sodium hydroxide. Alum (AlK(SO₄)₂), ferrous sulfate (FeSO₄), and stannous chloride (SnCl₂) were used as mordants. The colour of each dyed fabric was investigated in terms of the L*, a*, b* and K/S values. The effects of different dye concentrations with the use of applying padding techniques in the dyeing process was investigated. The colour fastness to washing, light, rubbing, water, and perspiration of dyed silk fabrics was performed according to the present ISO standard. Silk fabric was dyed by using a natural indigo colourant, applying one with metal mordant and one without giving the silk fabric a blue shade. However, a greenish blue shade was found as a dyeing result by adding a ferrous sulfate mordant. The fastness properties of washing, water, perspiration, and rubbing were very good level. However, a fair rating level was observed using a light fastness dyeing technique.

Abstract: Water adsorption in proteins is the crucial process of protein folding and structure stabilizing. Adsorption of water on proteins can be evaluated by near-infrared spectroscopy, a useful technique for observing combination frequency of a water molecule. In this work, albumin, lysozyme, and silk, were used as models for α-helix and β-pleated sheet proteins. Their NIR spectra during water adsorption process were measured by using an NIR spectrometer equipped with a transflectance accessory. Moreover, the quantitative adsorption of water was determined by gravimetric technique. The results indicate that, there are five different NIR absorptions arise from the OH combination frequencies of water adsorbed by albumin in the 5300-5100 cm^-1 region. But there are only four absorptions for lysozyme and silk. The OH combination frequencies arising from water molecules in albumin indicate that it acquires free water molecules (5280 cm^-1) and adsorbed water molecules through carbonyl-water interactions (5248 and 5160 cm^-1) and amino-water interactions (5200 and 5120 cm^-1). Interestingly, there is no indication for the presence of free water molecules in lysozyme and silk. Furthermore, the gravimetric results indicate that the rate of water adsorbed follows the order R_W.Alb<R_W.Lys<R_W.Sil and total mass of water adsorbed per gram solid follows the order W_Alb<W_Lys=W_Sil.

Abstract: The objective of this study is to provide a method which allows introduction of functional groups onto silk cocoon surface. Plasma irradiation is straight-forward, relatively noninvasive and requires minimal chemical reaction steps to alter surface hydrophilicity of polymeric materials. Introduction of oleic acid on pristine and air-zero irradiated silkworm (Bombyx mori) cocoons was carried out via acid-catalyzed esterification. The reaction was confirmed by ATR-FTIR spectroscopy. Functionalization of oleic acids onto silkworm cocoons favors hydrophilic surface. In addition to the acid-catalyzed esterification, amide hydrolysis takes place as a side reaction. This reaction leads to formation of hydrophilic carboxylic acids and amines. The change in hydrophilic functionalities leads to an increase in cocoon wettability as confirmed by contact angle measurements.

Abstract: Natural dye solution from longan leaves was applied to the simultaneous dyeing of silk fabric and using alum, copper sulfate, ferrous sulfate and stannous chloride as a mordanting agents. The dyeing properties and effects of simutaneous-mordanting on the hue, colour strength and colour value were revealed. The results show that The K/S values increased with an increase of metal mordant concentration. The mordant activity sequence was CuSO₄> FeSO₄> AlK(SO₄)₂ > SnCl₂. The obtained colour values show that silk fabrics dyed without mordant exhibited dark brown colour, while those mordanted with aluminum potassium sulfate (alum), stannous chloride and copper sulfate showed a variety of medium to dark brown shades. With ferrous sulfate, the colour shade was darker and duller. The colour fastness results showed good to very good level.

Abstract: In this research, the dyeing behavior of silk fabrics with lac was studied. The effect of different mordants concentration (potassium aluminium sulfate or alum, stannous chloride, ferrous sulfate and sodium chloride) with simultaneous mordanting procedures using pad-dry and pad-batch techniques on colour characteristics of the dyed samples was investigated. The colour fastness tests were washing and light of the dyed samples, the test results were determined according to the present ISO standard.The results show that silk fabric dyed without and with stannous chloride and sodium chloride mordant gave a shade of light pink, while those mordanted with aluminum potassium sulfate, had noticeably pink shade. The colour shade was light grey shades was obtained by adding ferrous sulfate mordant. The washing fastness property showed very poor level, while light fastness was fair level.