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1

Designing a Three-Dimensional Woven Fabric Structure as an Element of a Baby Stroller

Bethalihem Samuel T., Barburski Marcin, Lemmi Tsegaye Sh.

Autex Research Journal

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2022

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Vol. 22, no. 2

148--154

EN

A baby stroller allows the transportation of a child over long or short distances. The materials used to produce the stroller make it heavy for users, which creates difficulties when lifting the stroller. The goal of this project was to design and fabricate a three-dimensional (3D) fabric structure that can be used as part of a stroller seat to improve its mechanical and physical properties. The idea of implementing a woven 3D system allows the development of an egg-shaped or shell-like structure as part of a stroller seat. The combination of double-woven material and honeycomb polypropylene (as the reinforcing material) was used to create a 3D composite structure. Single and double layers of polypropylene honeycomb sandwiched within layers of linen flax fabric were used to prepare the composite samples. Subsequently, tests on mechanical and physical properties, such as density, flexural strength, and tensile strength, were carried out. Analysis of the results showed that the composite with one layer of honeycomb has half the density of polyvinyl chloride.

2

Development and mechanical characterization of polylactide green composites reinforced with natural fibers

Mazur Wiktoria, Mazur Kamila E., Kuciel Stanisław

Inżynieria Materiałowa

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2021

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Vol. 42, nr 2-3

33--38

EN

An attempt was made to modify compostable polymer composites based on polylactide (PLA). Composites based on PLA with the addition of coconut fibers, wood fibers, flax fibers and corn particles were produced, and their weight friction was 15%. The composites prepared by means of injection molding were subjected to mechanical characteristics (tensile, bending and impact strength). Due to the intended use (elements of small orthoses) of the produced materials, composites were subjected to hydrolytic degradation in physiological saline solution at 38°C. The test results showed that the addition of natural fillers will positively affect the stiffness of the produced composites, with a slight decrease in tensile strength. The highest values were obtained for composites with the addition of wood fibers, where the improvement of Young’s modulus was approx. 50%, while the decrease in tensile strength was only 8% compare to unmodified PLA. Additionally, a decrease in mechanical properties was observed after 42 days of incubation in water. The lowest decrease in the properties obtained during the flexural tests was characteristic of unmodified PLA, while the highest decrease was observed in composites with bamboo fiber. The research objective constructed in this way confirms the validity of the using biobased fillers. The produced composites not only have high mechanical properties, but are also an excellent alternative to petrochemical polymer composites, the recycling of which is burdensome for the human natural environment.

PL

Podjęto próbę modyfikacji kompostowalnych kompozytów polimerowych na osnowie polilaktydu (PLA). Wytworzone zostały kompozyty na bazie PLA z dodatkiem włókien kokosowych, mączki drzewnej, włókien lnianych oraz cząstek kukurydzy, a ich udział wagowy wynosił 15%. Tak przygotowane kompozyty za pomocą formowania wtryskowego zostały poddane charakterystyce mechanicznej (rozciąganie, zginanie oraz udarność). Ze względu na przewidziane zastosowanie (elementy małych ortez) wytworzonych materiałów zostały one poddane hydrolitycznej degradacji w roztworze soli fizjologicznej w temperaturze 38°C. Wyniki badań pokazały, że dodatek naturalnych napełniaczy pozytywnie wpłynął na sztywność wytworzonych kompozytów, przy równoczesnym nieznacznym spadku wytrzymałości na rozciąganie. Najwyższe wartości uzyskano dla kompozytów z dodatkiem mączki drzewnej, gdzie poprawa modułu Younga wynosiła ok. 50%, a spadek wytrzymałości na rozciąganie wynosił tylko 8% w porównaniu z niemodyfikowanym PLA. Dodatkowo zaobserwowano pogorszenie właściwości mechanicznych po 42 dniach inkubacji w wodzie. Najmniejsze różnice we właściwościach otrzymanych podczas próby zginania zaobserwowano dla niemodyfikowanego PLA, a największe dla kompozytów z włóknem bambusowym. Tak skonstruowany cel badań potwierdza słuszność stosowania biopochodnych napełniaczy. Wytworzone kompozyty nie tylko posiadają bardzo dobre właściwości mechaniczne, ale również są doskonałą alternatywą dla petrochemicznych kompozytów polimerów, których recykling obciąża naturalne środowisko człowieka.

3

Analysis of Mechanical Properties of Unidirectional Flax Roving and Sateen Weave Woven Fabric-Reinforced Composites

Lemmi Tsegaye Sh., Barburski Marcin, Samuel Bethalihem

Autex Research Journal

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2021

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Vol. 21, no. 2

218--223

EN

Natural fiber-reinforced composites are getting more attention from researchers and manufacturing companies to replace metals and synthetic materials that have dominated the manufacturing industries. In this study, the mechanical properties of unidirectional (UD) flax roving-reinforced composites and woven fabric-reinforced composites were investigated. Three different composites were prepared from flax rovings, which have the same linear density and epoxy resin matrix, with different reinforcement and composite preparation methods. The samples were subjected to experimental tests of flexural rigidity and tensile strength in a parallel and perpendicular direction to fiber orientation. The test results showed that flexural rigidity and tensile strength of flax fiber-reinforced composites are highly dependent on the direction of fiber orientation. The results also reveal that in a parallel direction to fiber orientation, UD composites have higher flexural rigidity and tensile strength than woven fabric-reinforced composite.

4

Effect of Abiotic Degradation on the Colorimetric Analysis, Mechanical Properties and Morphology of PLA Composites with Linen Fibers

Tor-Świątek Aneta, Garbacz Tomasz

Advances in Science and Technology. Research Journal

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2021

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Vol. 15, no 1

99--109

EN

The manufacturing of composites from biomaterials enables the production of environmentand user-friendly biodegradable products. The matrix of such composite materials is made of biopolymers such as PLA or PGA, while the reinforcement is usually made of natural fibers. Such composites have unique physical and mechanical properties as well as distinctive, eye-catching performance and aesthetic characteristics such as texture, color or roughness. This paper presents the results of colorimetric examination of polymer-linen biocomposite materials under abiotic degradation. The colorimetric examination was made based on a CIELAB model determining the values of lightness, color saturation, chromatic colors and total color difference. The SEM morphology of the specimen surface fracture was also examined. The obtained results show a significant effect of abiotic degradation on the tested parameters.

5

Effect of flax fibers addition on the mechanical properties and biodegradability of biocomposites based on thermoplastic starch

Borowski Gabriel, Klepka Tomasz, Pawłowska Małgorzata, Lavagnolo Maria Cristina, Oniszczuk Tomasz, Wójtowicz Agnieszka, Combrzyński Maciej

Archives of Environmental Protection

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2020

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Vol. 46, no. 2

74--82

EN

The research was intended to develop a biocomposite as an alternative biodegradable material, for the production of, e.g., disposable utensils. The author’s tested thermoplastic maize starch, both without additives and with the addition of crumbled flax fiber in the share of 10, 20 and 30 wt%. The plasticizer added was technical glycerin and the samples were produced by a single-screw extruder. The mechanical strength tests were performed, including the impact tensile test and three-point bending flexural test. Afterwards, the samples were tested for biodegradability under anaerobic conditions. The methane fermentation process was carried in a laboratory bioreactor under thermophilic conditions with constant mixing of the batch. All samples proved to be highly susceptible to biodegradation during the experiment, regardless of the flax fiber share. The biogas potential was about 600 ml·g-1, and the methane concentration in biogas ranged from 66.8 to 69.6%. It was found, that the biocomposites can be almost completely utilized in bioreactors during the biodegradation process. The energy recovery in the decomposition process with the generation of significant amount of methane constitutes an additional benefit.

6

Nanostructural Biochemical Modification Of Flax Fiber In The Processes Of Its Preparation For Spinning

Koksharov S., Aleeva S., Lepilova O.

Autex Research Journal

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2015

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Vol. 15, no. 3

215--225

EN

The elaborated principles of nanoengineering of linen textile materials implement the techniques of spatially localized effects of protein catalysts on polymeric cellulose companions with selective splitting of impurity compounds without damaging technologically necessary nano-sized formations of binders in the fiber structure. The ranges of optimal values of the residual content in flax fiber prepared for spinning are identified on the basis of the analysis of the successive stages of enzymatic and peroxide treatments contribution to the breakdown of polymers and the differentiation of the influence of impurities on the yarn technological properties. The recommended level of residual pectin, lignin and hemicellulose (wt. %) is: after enzymatic treatment P1 = 1,0±0,1; L1 = 3,9±0,3; Hc1 = 11,0±1,0; after peroxide bleaching P2 = 0,4±0,05; L2 = 2,3±0,3; Hc2 = 7,5±0,5. The required level of fiber structural modification at the stage of preparing roving for spinning can be achieved through use of protein catalysts whose globule size is 50...100 nm. The use of enzymes with these dimensional characteristics helps to ensure breaking of polymer adhesives on the surface of incrusts and in the areas of intercellular formations, which hinder fiber crushing, without damaging nano-sized binding fractions. The implementation of this method contributes to a significant improvement in the uniformity of structural and physical and mechanical properties of flax yarn. Increase in yarn fineness and strength properties of semi-finished products, as well as improvement of deformation properties and reduction of yarn breakages during the spinning processes are achieved.

7

Polyamides from renewable sources as matrices of short fiber reinforced biocomposites

Kuciel S., Koźniar P., Liber-Kneć A.

Polimery

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2012

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T. 57, nr 9

627-634

EN

At present, in production of commercially available biopolyamides, castor oil is used as one of raw materials. In this paper possibilities of processing biocomposites based on biopolyamide (commercially delivered by Chinese company Suzhou Hipro Polymers) filled with 10 or 20 wt. % of glass, carbon or flax fibers were presented. Tensile properties (tensile strength, modulus of elasticity and elongation at break) of the composites in their conditioned state and afterwater soaking were discussed. As the results showed, a strong effect of reinforcement was obtained for all of the composites. The composites with glass and flax fibers have a great elongation and impact resistance. To evaluate fatigue stress of tested materials, simplified shortened Lehr’s method was used. The results of this work can be used in the designing process of structural materials with varying stiffness and ability to dissipate energy depending on the expectations of the recipient.

PL

W pracy zaprezentowano aktualne możliwości wytwarzania i modyfikacji poliamidów z surowców odnawialnych. Na przykładzie poliamidu otrzymywanego z oleju rycynowego i produkowanego na skalę przemysłową (Hiprolon 211) przedstawiono wyniki badań kompozytów z dodatkiem 10 lub 20 % mas. włókien — szklanych, węglowych lub lnianych. Porównano podstawowe właściwości wytrzymałościowe czystego biopoliamidu i jego kompozytów o różnym stopniu napełnienia (rys. 2—4). Wprowadzenie włókien we wszystkich przypadkach dało wyraźny efekt wzmocnienia. Wyznaczono wartości gęstości, temperatury mięknienia Vicata, udarności określanej metodą Charpy'ego z karbem (tabela 1), a także chłonności wody po 1, 7 i 30 dniach moczenia. Zbadano również zmiany właściwości wytrzymałościowych po 30-dniowej inkubacji w wodzie (rys. 6 i 7) czystego biopoliamidu i kompozytów z dodatkiem 10 % mas. napełniaczy. Techniką SEM wykonano fotografie powierzchni przełomów po rozciąganiu wytworzonych kompozytów. Widoczne są na nich charakterystyczne cechy struktury i morfologia różnych włókien (rys. 3). Przedstawiono rezultaty badań dynamicznych kompozytów, a w szczególności poziomy sił wymuszających, średnie wydłużenie oraz energie dyssypacji odpowiadających narastającym ilościom pętli mechanicznej histerezy (tabela 2, rys. 9). Porównano pętle histerezy kompozytów z włóknami szklanymi, węglowymi i lnianymi (rys. 8). Wyniki przedstawionych badań wykazały, że istnieją duże możliwości projektowania właściwości wytrzymałościowych kompozytów na osnowie długołańcuchowych biopoliamidów, ponieważ właściwości te zależą od rodzaju oraz ilości wprowadzanych włókien.

8

Sztywne pianki poliuretanowe modyfikowane surowcami odnawialnymi

Prociak A., Michałowski S.

Czasopismo Techniczne. Mechanika

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2009

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R. 106, z. 1-M

249-253

PL

Badano wpływ surowców odnawialnych w postaci poliolu z oleju rzepakowego i włókna lnianego na wybrane właściwości sztywnych pianek poliuretanowych. Otrzymano materiały porowate o gęstości pozornej w zakresie 30-40 kg/m3 i anizotropowej strukturze komórkowej. Dokonano oceny wpływu napełniacza włóknistego na przebieg procesu spieniania, strukturę komórkową oraz właściwości mechaniczne i termoizolacyjne otrzymanych materiałów porowatych. Stwierdzono możliwość zwiększenia surowców biodegradowalnych w recepturach pianek sztywnych bez pogorszenia ich właściwości fizyko-mechanicznych.

EN

Influence of renewable raw materials as rapeseed oil-based polyol and flax fibers on selected properties of rigid polyurethane foams was investigated. Cellular materials with apparent density 30-40 kg/m3 and anisotropic cell structure were prepared. The influence of fiber filler on foaming process, cell structure, mechanical and heat insulating properties of the porous materials was estimated. Possibility of increasing biodegradable raw materials in formulation of rigid foams was found without worsening their physical-mechanical properties.