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1

Thermal Comfort Properties of Bamboo/Silk Fabrics

Geethanjali T., Prakash C., Ramesh Babu V., Jebastin Rajwin A.

Fibres & Textiles in Eastern Europe

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2021

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Vol. 29, no. 2 (146)

36--40

EN

The thermal resistance of fabrics containing silk showed a higher value in comparison with lyocell-rich blends. The water vapour permeability, absorbency and wickability of lyocell and lyocell-rich blends were found to be superior as compared to 100% silk fabrics. With respect to aesthetic comfort properties, the drape of the lyocell rich fabrics was good in comparison with 100% silk fabrics.

PL

W badaniu stwierdzono, że tkaniny zawierające jedwab mają wyższą wartość oporu cieplnego w porównaniu z mieszankami bogatymi w Lyocell. Stwierdzono również, że przepuszczalność pary wodnej, nasiąkliwość i podatność na skręcanie Lyocell i mieszanek bogatych w Lyocell były lepsze w porównaniu ze 100% tkaninami jedwabnymi. Pod względem komfortu estetycznego, tkanin bogatych w Lyocell wypadły lepiej, w porównaniu z tkaninami 100% jedwabnymi.

2

Synthesis of Conductive Cocoon Silk Composites

Kaitsuka Y., Goto H.

Fibres & Textiles in Eastern Europe

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2017

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Vol. 25, no. 1 (121)

17--23

EN

Herein we report on the preparation of polyaniline (PANI) composite using a cocoon by in situ chemical oxidative polymerisation. The composites thus prepared were characterised by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), infrared (IR), and electron spin resonance (ESR) spectroscopy. We confirmed the PANI/cocoon composite and subsequent carbonisation allowed the formation of micro-sized wafer-shaped carbon. The polymerisation reaction occurs in a chiral reaction field of the silk surface, which can be referred to as bio-interface polymerisation.

PL

W artykule opisano przygotowanie polianilinowych (PANI) kompozytów przy zastosowaniu kokonów i przeprowadzeniu in situ chemicznej utleniającej polimeryzacji. Wytworzone kompozyty zostały scharakteryzowane za pomocą skaningowego mikroskopu elektronowego (SEM), analizy termograwimetrycznej (TGA), spektrofotometrii w podczerwieni (IR) oraz elektronowego rezonansu spinowego (ESR). Potwierdzono, że otrzymane kompozyty, a następnie ich karbonizacja umożliwiły powstawanie mikroskopijnej wielkości płytek węglowych.

3

Fabrication of Electrical Conductivity and Reinforced Electrospun Silk Nanofibers with MWNTs

Zuo L., Zhang F., Gao B., Zuo B.

Fibres & Textiles in Eastern Europe

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2017

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Vol. 25, no. 3 (123)

40--44

EN

Electrospinning is an effective technique for fabricating submicron to nanoscale fibers from synthetic polymer as well as natural proteins. In this study, multiwalled carbon nanotubes (MWNTs) were embedded via electrospinning by adding MWNTs into the spinning dope, and found to be well aligned along the fiber axis in the silk fibroin nanofibers. The morphology and microstructure of the electrospun nanofibers were characterised using a field emission scanning electron microscope (FESEM) and Transmission electron microscopy (TEM). X-ray diffraction (XRD) and TG-DTA were used to study the crystal structure of the silk/MWNTs composite nanofibres, carried out to alter the strength, toughness and electrical conductivity of silk nanofibers by adding a small amount of MWNTs. The electrospun random silk mats with 1% MWNTs had a Young’s modulus, ultimate tensile strength and strain of 107.46 ± 9.15MPa, 9.94 ± 1.2MPa and 9.25 ± 1.5%, respectively, and electrical conductivity increased to 1.2×10-4S/cm. The silk/MWNTs composite nanofibres could potentially be applied in nerve repair materials owing to their excellent mechanical properties and electrical conductivity.

PL

Za pomocą elektroprzędzenia wytworzono jedwabne nanowłókna z dodatkiem nanorurek węglowych. Zbadano wpływ nanorurek węglowych na morfologię, strukturę, właściwości mechaniczne i przewodność elektryczną j nanowłókien. Morfologię i mikrostrukturę otrzymanych nanowłókien scharakteryzowano za pomocą skaningowego mikroskopu elektronowego (FESEM) i transmisyjnej mikroskopii elektronowej (TEM). Wyniki badań rentgenowskich i cieplnych wykazały, że dodanie nanorurek nie wywierało istotnego wpływu na strukturę nanowłókien w porównaniu do niemodyfikowanych nanowłókien fibroinowych. Poprzez dodanie nanorurek uzyskano polepszenie właściwości mechanicznych, została również polepszona przewodność elektryczna nanowłókien. Na podstawie otrzymanych wyników stwierdzono, że jedwabne nanowłókna z dodatkiem nanorurek węglowych mogą być stosowane w materiałach do naprawy nerwów dzięki ich doskonałym właściwościom mechanicznym i przewodności elektrycznej.

4

Structure and Physical and Chemical Properties of Fibres from the Fifth Larval Instar of Caddis-Flies of the Species Hydropsyche angustipennis

Tszydel M., Sztajnowski S., Michalak M., Wrzosek H., Kowalska S., Krucińska I., Lipp-Symonowicz B.

Fibres & Textiles in Eastern Europe

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2009

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Vol. 17, no. 6 (77)

7--12

EN

Caddis-flies (Trichoptera) belong to insects closely related to butterflies and, like the latter, have a gift for spinning silky floss. It is an especially attractive ability for modern science as it is looking for new natural materials applicable in human life. The aim of our study was to compare the properties of trichopteran silky floss with those of raw silk and fibres from a cobweb. Knowledge of the chemical composition and structure of these fibres, along with their microand macroscopic features and morphological properties, will allow to assess the usefulness of this material. It is most likely that the product from the silk glands of caddis-flies could be applied in medicine. The material of our investigations came from one of the Trichoptera species Hydropsyche angustipennis. Fibres were taken from live advanced/matured larvae (in the 5th larval instar). The larvae were raised separately in a plastic box, without food and with a systematic water exchange in order to eliminate the influence of contamination by trichopteran excrement. Fibres of the caddis-flies investigated were elements of their web and the lining of the pupal shelter, while the raw silk came from a Bombyx mori cocoon and the spider’s silk from a Tegenaria domestica cobweb. The investigations included identification of the material and the density of the caddis-fly fibres. Additionally, the structure of these fibres was examined by means of IR absorption spectroscopy, and the FTIR method made it possible to confirm the presence or absence of functional groups in the silky floss of various groups of invertebrates. Observations with the use of scanning electron microscopy (SEM) revealed the spatial structure and crosssectional shape of the fibres under investigation.

PL

Chruściki (Trichoptera) są owadami posiadającymi zdolność do produkcji oprzędu w fazie larwalnej, cenną umiejętność zwłaszcza dla współczesnej nauki, która poszukuje materiałów pochodzenia naturalnego. Celem pracy było porównanie właściwości wydzieliny gruczołów przędnych chruścików z jedwabiem klasycznym i pajęczym. Do badań użyto włókien chruścikowych pochodzących z sieci łownych oraz wyściółki domku poczwarkowego (puparium), natomiast jedwab naturalny pochodził z kokonów poczwarkowych jedwabnika Bombyx mori a pajęczyna od pająka Tegenaria domestica. Badania obejmowały rozpoznanie rodzaju tworzywa włókna, wyznaczenie gęstości włókien chruścikowych; dodatkowo przeprowadzono badania budowy chemicznej włókien techniką spektroskopii absorbcyjnej w podczerwieni. Metoda FTIR pozwoliła na porównanie obecności/braku podstawowych grup funkcyjnych znajdujących się w składzie chemicznym oprzędu różnych grup bezkręgowców. Badania z zastosowaniem elektronowej mikroskopii skaningowej SEM pokazały natomiast strukturę przestrzenną włókien oraz kształt przekroju poprzecznego.

5

Electrokinetic Study of Water Hardness during Acid Dyeing with Silk

Kan C. W.

Fibres & Textiles in Eastern Europe

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2008

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Vol. 16, no. 3 (68)

99--101

EN

In this paper, the effect of water hardness, expressed in CaCO3, on the dyeing of silk with acid dye under acid, alkaline and isoelectric point dyeing conditions was studied using the zeta potential method. Under acidic conditions and in the presence of calcium ion, the positive zeta potential of silk was found to decrease with a reduction in dye adsorption. Such a phenomenon might be due to the presence of cation which increased the dyeing potential barrier at the interface between fibre and dye solution. This would result in a higher resistance of dye anions passing through the interface. Under alkaline conditions the zeta potential of silk was negative and resulted in a strong potential barrier against the dye anions. The presence of calcium ions would result in a decrease in the absolute value of the zeta potential of silk fibre, with an overall increase in dye absorption. At the isoelectric point, the zeta potential of the silk fibre was found to be near zero, and the dye adsorption was not influenced by the cations. These results showed that calcium ions could have a strong electrolytic effect on dyeing, even at very low concentrations.

PL

Badano wpływ twardości wody, wyrażonej w CaCO3, na barwienie jedwabiu barwnikami kwasowymi w obecności kwasu i zasady oraz izoelektryczny punkt barwienia używając metody potencjałów. W środowisku kwaśnym i w obecności jonów wapnia, dodatni potencjał zeta jedwabiu spadał wraz z redukcją barwnika. Zjawisko to może mieć związek z obecnością kationów, które zwiększają próg energetyczny reakcji na granicy faz między włóknem a roztworem barwnika. To może powodować wyższą rezystancję dla anionów barwnika przechodzących przez granicę faz. W środowisku alkalicznym potencjał zeta jedwabiu był ujemny i powodował wysoki próg energetyczny w stosunku do anionów barwnika. Obecność jonów wapnia może powodować spadek całkowitej wartości potencjału zeta włókien jedwabiu, w ogólnym wzroście w poborze barwnika. W punkcie izoelektrycznym potencjał zeta włókien jedwabiu znajduje się blisko zera, a kationy nie mają wpływu na absorpcję barwnika. Wyniki te pokazują, że jony wapnia mogą mieć istotny elektrokinetyczny wpływ na barwienie, nawet w małym stężeniu.

6

Extraction of natural dyes from african marigold flower (Tagetes erecta L.) for textile coloration

Jothi D.

Autex Research Journal

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2008

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Vol. 8, no. 2

49--53

EN

African marigold [Tagetes erecta L.], a major source of carotenoids and Lutin, is grown as a cut flower and a garden flower, in addition to being grown for its medicinal values. Marigold flowers [Tagetes], which are yellow to orange red in colour, are a rich source of lutein, a carotenoid pigment. Nowadays, Lutein is becoming an increasingly popular active ingredient used in the Food Industry and Textile coloration. This pigment has acquired greater significance because of its excellent colour value. Although marigold flower extract has been used in veterinary feeds, the potential use of marigold as a natural textile colorant has not been exploited to its full extent. This is due to the lack of information on its safety, stability, and compatibility in textile coloration. In this study, an experiment was conducted to study the use of an extract isolated from marigold as a natural dye. The dye potential of the extract was evaluated by dyeing, using the flower, in 100 % cotton and silk fabrics under normal dyeing conditions. Studies of the dyeability, wash fastness, light fastness, and colour hue were undertaken. The, L,a and 'b' of materials dyed using the extract were studied with the use of Computer Colour Matching software. The surface colour was not affected by washing, and the quality of the flower was maintained even washing at 60o C for 30 minutes. Studies have indicated that the change of some of the colors have been noticed after washing with soap. Most of the metal salts exhibited the highest K/S values, due to their ability to form coordination complexes with the dye molecules. These findings reveal that the extract of Marigold flower can be used for coloration of !00 % cotton, silk, and wool fabrics. This article deals with the chemistry, processing, and stability of the pigment and its applications in textile coloration.

7

Effect of water hardness on acid dyeing with silk

Kan C. W.

Autex Research Journal

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2008

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Vol. 8, no. 2

54--56

EN

In this paper, the effect of water hardness, expressed in CaCO3 equivalent, on the dyeing of silk with acid dye under acid, alkaline and isoelectric point dyeing conditions was studied by the zeta potential method. Under acid conditions and in the presence of the calcium ion, the positive zeta potential of silk was found to decrease with a reduction in the dye adsorption. Such a phenomenon might be due to the presence of cation, which increases the dyeing potential barrier at the interface between the fibre and dye solution. This would result in a higher resistance of dye anions passing through the interface. Under alkaline conditions, the zeta potential on silk was negative and resulted in a strong potential barrier for the dye anions. The presence of the calcium ion would result in a decrease in the absolute value of zeta potential of silk fibre, with an overall increase in dye absorption. Under the isoelectric point, the zeta potential of silk fibre was found to be near zero and dye adsorption was not influenced by the cations. These results demonstrate that the calcium ion could produce a strong electrolytic effect on dyeing, even under very low concentrations.

8

The tensile behaviour of spider silk

Van Nimmen E., Gellynck K., Van Langenhove L.

Autex Research Journal

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2005

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Vol. 5, no. 3

120--126

EN

Spider silk has attracted the interest of several researchers in recent years because it displays a unique combination of high tensile strength, high breaking strain and an ultra-low weight. Hitherto, the focus has always been on dragline and viscid silk, whereas research on spider cocoon silk is limited. In order to explain the structure-property relationship of spider silk, the stress-strain behaviour of cocoon and dragline silk is compared in this study. It is shown that both fibres have completely different stress-strain behaviours.In addition, the influence of the testing speed is investigated. For cocoon silk, lower testing speeds result in lower strength, stiffness and higher post-modulus. When the stress-strain curve is simulated by an extended Maxwell model, as testing speed increases, the level of the hardening region is higher, the yield region moves to higher strains and the hardening region in the stress-strain curve becomes more horizontal. However, a speed of 20 mm/min can be considered as a saturation point where the effect of the speed decreases. The influence of the testing speed on dragline silk is clearly less pronounced than for cocoon silk. However, a more detailed study of the stress-strain curves of dragline revealed different possible shapes for the stress-strain behaviour of dragline silk.

9

Study of property & structural variants of mulberry and tasar silk filaments

Das S., Chattopadhyay R., Gulrajani M. L., Sen K.

Autex Research Journal

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2005

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Vol. 5, no. 2

81--86

EN

The tensile behaviour of fully degummed filaments of two commercial varieties of silk produced in India, namely mulberry (Bombyx mori) and tasar (Antheraea mylitta), has been investigated in dry and wet state. The tensile properties were correlated with the structures and morphologies of these two varieties of silk. The tenacity and elongation at break of these silks were not significantly different in dry and wet state; however, a slight reduction in initial modulus was noticed in wet state. The stress-strain behaviour of mulberry silk filament was different from that of tasar in that it demonstrated a characteristic yield point, lower modulus and elongation at break twice as high as that of mulberry. The characteristic stress-strain behaviour of theses two varieties of silk was correlated with density, birefringence, orientation index, sonic modulus and amino-acid composition. Poor orientation and less order in tasar are related to the higher percent of bulky groups present in fibroin.

10

Studies on structure and properties of nephila-spider silk dragline

Rengasamy R. S., Jassal M., Rameshkumar C.

Autex Research Journal

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2005

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Vol. 5, no. 1

30--39

EN

Spider dragline silk is an extremely strong biopolymer and has unique combination of desirable mechanical properties. In the present paper dragline of Golden Nephila spider was studied for dimensional, structural, physical and tensile properties. The test results established significant variability in diameter and denier of dragline filaments. The filaments possessed nearly circular cross-section and were found to be sensitive to moisture. The draglines exhibited super contraction in water. It has high strength and large elongation to break (45.9 cN/tex and 38.7 %, respectively). X-ray crystallinity of 17.5 % was obtained. The fibres were also subjected to thermo- mechanical and dynamic mechanical analysis.

11

Nić pajęcza - własności wytrzymałościowe, próby syntezy

Wójtowicz W.

Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska

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2004

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z. 24

231-238

PL

Praca opisuje sposób wytwarzania przez pająka jego mci, jej skład chemiczny oraz własności wytrzymałościowe. Przedstawione są metody produkowania syntetycznego jedwabiu pająka, porównanie własności mechanicznych z nicią naturalną a także zastosowanie w medycynie.

EN

The paper describes the way of treads formation by spiders, their chemical composition and strength properties. The methods of synthetic spider silk manufactured, comparison with natural thread, as well as their application in medicine are presented, too.

12

Preparation of natural silk waste solutions by high frequency heating

Nabieva I., Sadriddinov B., Khasanova M., Alimova K., Klemola K., Pearson J.

Autex Research Journal

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2004

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Vol. 4, no. 3

143--146

EN

Natural silk waste is an important by-product of the silk industry in Uzbekistan. Solutions to the problem of natural silk waste have been used to improve the properties of the locally produced polyacrylonitrile fibre. Nitron, and the effectiveness of this dissolution process, are very important to the textile industry in Uzbekistan. Previous methods used to dissolve natural silk waste have been time-consuming and relatively inefficient. This paper describes a new method for dissolving natural silk waste, using a high-frequency electromagnetic field.

13

Biomimetic manufacturing of customised novel fibre proteins for specialised applications

Teulé F., Aubé C., Ellison M., Abbott A.

Autex Research Journal

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2003

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Vol. 3, no. 4

160--165

EN

Using spider silk and collagen as a model, we have investigated the role that various protein primary structural components play in fibre production. Spidroins, spider dragline silk protein components, are essentially characterised by an amino-acid repeat containing a glycine-rich motif (amorphous) followed by an alanine-rich motif (crystalline, putatively responsible for fibre strength). We have tested the importance of alanine runs in these proteins and the role of this motif in the mechanical properties of the resulting fibre. To test the importance of alanine-rich motifs in the spidroin-1 proteins, we engineered three types of spidroin-1-like genes containing sequence encoding for different amounts of alanine repeats in the protein (normal, low, and no alanine residues). We also have engineered three copolymer collagen-spidroin-1 genes using each of the three spidroin-1 synthetic genes. These copolymers were mimicked on the existing natural block collagen-silk-like protein copolymer found in the byssus thread of marine mussels. All of these constructs were introduced in yeast (Pichia pastoris) for protein production. We are currently purifying each of the recombinant proteins for structural analysis (CD-spectroscopy).

14

O pewnych wadach strukturalnych jedwabiu powodujących błędy tkaniny

Słodowy J.

Przegląd Włókienniczy + Technik Włókienniczy

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2000

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nr 5

20-23

PL

Niniejszym podjęta została próba wykazania, że równopostaciowy jedwab po przejściu przez barierę cierną może w pewnych warunkach utracić swą równomierność struktury, a to staje się przyczyną groźnej wady strukturalnej tkaniny.