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1

Strength Analysis Aspects of Psyllium/Thermoplastic Starch Films under Impact Loading Conditions

Beer-Lech Karolina, Kołodziej Paweł, Skic Anna, Branco Ricardo

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no 2

385--393

EN

Tensile test under quasi-static loads conditions is usually used to determine the mechanical strength of thermoplastic starch films. This kind of test does not fully illustrate the load conditions for packaging films, which, under the conditions of use, are succumb to dynamic loads. Thus, the aim of the study was to present the possibilities of using a patented soft tissues measurement testing station to analyze the mechanical strength of thermoplastic starch (TPS) films under impact loading conditions. Two groups of film specimens containing the addition of psyllium husks (TPS/PH) and psyllium flour (TPS/PF) were used for the measurements. The casting method was applied, and glycerol was used as a plasticizer. Microstructure of the specimen surface was analyzed by stereoscopic microscopy. Specimens with the addition of psyllium flour had a more uniform microstructure. The maximum breaking forces obtained during impact tests for these films were 5 times higher than specimens containing psyllium seed husk. The same behaviour was found with respect to stresses with average values of 48.6 MPa for TPS/PF and 20.2 MPa for TPS/PH. Moreover, research confirms usefulness of patented soft tissues measurement testing station to analyse the mechanical strength of thermoplastic starch films.

2

Research on deposition of silver nanoparticles at the cellulose/NaNO3 electrolyte interface

Janusz Władysław, Kowalska Klaudia, Skwarek Ewa

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 4

art. no. 173554

EN

Currently the research on silver nanoparticles is of great demand owing to their antibacterial properties. One of the possibilities is the study of the silver deposition on the cellulose fibers, and more specifically of the silver nanoparticles and cellulose particles. The research was aimed at obtaining silver nanostructures by reducing ions with formaldehyde and then stabilizing them with the Pluronic solution. A suspension system containing cellulose fibers and silver nanoparticles was prepared in the basic electrolyte NaNO3. There were analyzed the following makes: pH of solutions, grain distribution and zeta potential ζ. Ag nanoparticles are largely applied in medicine, pharmacy, cosmetology and textile industry. Great interest in the nanostructures allows for developing knowledge about them, and thus creating the possibility of further improvement of their properties for subsequent applications.

3

Flax pomace as a substitute for wood raw material in lignocellulosic composite technology

Lipska Karolina, Goławski Sebastisn

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2023

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No. 123

86--95

EN

Flax pomace as a substitute for wood raw material in lignocellulosic composite technology. In the present study, composites made from flax seed pomace and PE, PP, PLA and modified starch were subjected quality parameter tests. Density, modulus of rapture (MOR), and modulus of elasticity (MOE) were examined, as well as water absorption and swelling to thickness after 2h and 24 h soaking in water, wettability and surface roughness. Addition of flax to different polymers caused significant changes of parameters but the level of influence of the addition varied between polymers. Although the characteristics of the produced biocomposites have been shown to be in general inferior to pure polymers, efforts should be made to improve these characteristics. Agri-food waste products can be a valuable raw material for the production of new type of biomaterials.

PL

Wytłoki lniane jako substytut surowca drzewnego w technologii kompozytów lingocelulozowych. Kompozyty wykonane z wytłoków z nasion lnu oraz HDPE, PP, PLA i skrobi poddano testom parametrów jakościowych. Zbadano gęstość, wytrzymałość na zginanie i moduł sprężystości, a także nasiąkliwość, zwilżalność i chropowatość powierzchni. Dodatek lnu do różnych polimerów spowodował znaczące zmiany parametrów, ale poziom wpływu dodatku różnił się między polimerami. Chociaż wykazano, że parametry jakościowe wytworzonych biokompozytów są niższe od czystych polimerów, należy podjąć wysiłki w celu poprawy tych właściwości. Produkty uboczne z przetwórstwa rolno-spożywczego mogą być cennym surowcem do produkcji nowych przyjaznych dla środowiska materiałów.

4

Corn pomace as a substitute for wood raw material in lignocellulosic composite technology

Lipska Karolina, Ufnowski Paweł

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2023

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No. 123

109--117

EN

Corn pomace as a substitute for wood raw material in lignocellulosic composite technology. Composites made from polymers PE, PP, PLA and modified starch with addition of corn pomace were produced and subjected quality parameters test. There were examined such parameters as: density, static bending strenght and modulus of elasticity and also water absorption and thickness swelling after 2 h and 24 h soaking in water, wettability and surface roughness. In general, the addition of corn pomace to polymers caused changes of parameters and through comparing parameters of different composites and control samples it was possible to indicate corn composite variants that occurs to have similar properties to pure polymer samples. Waste products should be seriously considered as a valuable substitute of wood raw material, but characteristics of composites should be improved through further research.

PL

Wytłoki kukurydziane jako substytut surowca drzewnego w technologii kompozytów lingocelulozowych. Wytworzono kompozyty z polimerów HDPE, PP, PLA oraz skrobi modyfikowanej z dodatkiem wytłoków ziaren kukurydzianych i poddano je badaniom parametrów jakościowych. Zbadano takie parametry jak: gęstość, wytrzymałość na zginanie statyczne i moduł sprężystości, a także spęcznienie na grubość oraz nasiąkliwość po 2 i 24 godzinach moczenia w wodzie, zwilżalność i chropowatość powierzchni. Dodatek wytłoków kukurydzianych do polimerów spowodował zmiany parametrów, a poprzez porównanie parametrów różnych kompozytów i próbek kontrolnych możliwe było wskazanie wariantów kompozytów zawierających wytłoki kukurydziane, które mają podobne właściwości do próbek czystego polimeru. Pozostałości produkcyjne przemysłu rolno-spożywczego powinny być brane pod uwagę jako wartościowy substytut surowca drzewnego, jednak parametry ich wytwarzania powinny być zoptymalizowane czemu służyć będą dalsze badania.

5

The influence of accelerated aging on selected mechanical properties of polypropylene with organic fillers

Szymiczek Małgorzata, Chomiak Monika, Chmielnicki Błażej, Sarraj Sara, Gołuch Paulina

Polimery

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2022

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Vol. 67, nr 7-8

308--316

EN

The aging effect in water atthe temperature of 100±2°C on selected mechanical properties of polypropylene with organic fillers (hemp chaff, a mixture of oak, birch and maple leaves) was investigated. A significant influence of the aging process on the impact strength and elongation at break was observed. The degradation processes were also visible on the surface of the samples.

PL

Zbadano wpływ starzenia w wodzie w temperaturze 100±2°C na wybrane właściwości mechaniczne polipropylenu z napełniaczami organicznymi (plewy konopne, mieszanina liści dębu, brzozy i klonu). Stwierdzono istotny wpływ procesu starzenia na udarność i wydłużenie względne przy zerwaniu. Procesy degradacji widoczne były również na powierzchni próbek.

6

Green hybrid polyethylene composites for biomedical application

Kufel Anna, Kuciel Stanisław

Inżynieria Materiałowa

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2022

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Vol. 43, nr 4

5--9

EN

The aim of the research was to study green polyethylene hybrid composites reinforced with natural fillers. In our study the green high-density polyethylene produced from sugarcane-based ethanol was used as a matrix. The basalt fibers, corncob granules, coffee, hazelnut shells and tuff were added to the matrix. The influence of the temperature on the mechanical properties were investigated. Scanning electron microscopy was used to assess the quality of adhesion of the natural fillers to the polymer matrix.

PL

Celem badań było wytworzenie hybrydowych kompozytów na osnowie zielonego polietylenu wzmocnionych naturalnymi napełniaczami. Polietylen o dużej gęstości wyprodukowany z trzciny cukrowej został użyty jako matryca polimerowa. Do matrycy dodawano włókna bazaltowe, śrutę kukurydzianą, kawę, łupiny orzechów laskowych i tuf. Zbadano wpływ temperatury na właściwości mechaniczne. Skaningowy mikroskop elektronowy został użyty, aby ocenić jakość adhezji naturalnych napełniaczy do polimerowej osnowy.

7

Mechanical Properties of Polylactide Matrix Composite Reinforced with Long Maize Stalk Fibers

Łączny Daniel, Macko Marek, Moraczewski Krzysztof

Advances in Science and Technology. Research Journal

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2022

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Vol. 16, no 1

104--112

EN

The aim of presented study was to investigate the effect of using long rotation maize stalk fibers as filler on the mechanical and thermomechanical properties of an injection molded biocomposite with a polylactide matrix using different fiber percentages. To evaluate the effect of maize stalk particle reinforcement on the PLA matrix, the mechanical properties of the biocomposites including tensile strength, tensile modulus, relative strain at maximum stress, strain at break, stress at break and Charpy unnotched impact strength were determined. From a mechanical point of view, the best fiber content was at 15% as it caused the least reduction in strain at break, stress at break, and strain at maximum stress relative to the polylactide matrix.

8

Characterization of the Structural and Physical Properties of the Thermoplastic Starch Film with Kaolinite and Beeswax Addition

Beer-Lech Karolina, Skic Anna, Skic Kamil, Stropek Zbigniew

Advances in Science and Technology. Research Journal

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2022

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Vol. 16, no 5

312--323

EN

The aim of the study was to investigate the influence of kaolinite (KA) and beeswax (BW) addition on the structural and physical properties of thermoplastic starch (TPS) films. The casting method was applied and glycerol was used as a plasticizer. Microstructure analyzes were made by a stereoscopic and a scanning electron microscope. Tensile tests were carried out under static load conditions at three different deformation velocities of V=0.0001, 0.001, and 0.01 m/s. The studies of surfaces characteristic were performed using water contact angle and water vapor isotherm measurements. The most homogeneous structure of the surface with higher mean values of failure stress and elasticity modulus was observed for thermoplastic starch films with kaolinite addition. The significant reduction in dynamics changes of water contact angle (10%) of BW films in the time 0-20s as well as tensile strength decrease was noted (compared to pure TPS films). The research results suggest the validity of using BW and KA to improve the barrier and mechanical properties of TPS films. Further research should focus on to improve the starch-beeswax-kaolinite combination and increase the homogeneity of the structure of films in order to upswing their simultaneous impact on barrier and mechanical properties.

9

Epoksydowane oleje roślinne : zastosowanie w nowoczesnych materiałach polimerowych

Janus Ewa, Musik Marlena, Wilpiszewska Katarzyna, Sałaciński Łukasz, Milchert Eugeniusz

Wiadomości Chemiczne

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2021

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[Z] 75, 9-10

1395--1411

EN

The growing, global concern for the natural environment contributes to the intensive research on at least partial replacing of petroleum-based raw materials with bio-renewable resources on an industrial scale. The chemical composition and oligomeric nature of plant oils make them a promising bio-renewable base for development of new polymer materials. The conversion of plant oils and fats to epoxidized plant oils (EO) and polyols are the processes intensively studied. Epoxides based on soybean oil, i.e. one of the most easily available vegetable oils, have a high potential for polymeric materials preparation. In addition, linseed and castor oils are of great importance in this area as well. This article presents the latest achievements in the production of novel polymer materials based on epoxidized vegetable oils and their derivatives. The importance and application of EO for polymer materials should be considered multidirectional. Epoxidized plant oils are the platform chemicals for polyethers, polyesters, polyurethanes and polyhydroxyurethanes, but also can act as modifiers for natural and synthetic polymers. Polymers based on epoxidized vegetable oils in combination with filler – including more and more popular natural fibers, allow to obtain biocomposites. Applying bioresin and natural reinforcement reduces the carbon footprint. Moreover, such materials may exhibit competitive properties against petrochemical polymer products and meet the requirements of the automotive, packaging, furniture, and construction industries. Additionally, obtaining materials showing functional properties, including shape memory and self-healing ability is also possible.

10

3D Ornamentowane zdefiniowane struktury krzemionkowe otrzymane przez okrzemki

Brzozowska Weronika, Wojtczak Izabela, Sprynskyy Myroslav, Buszewski Bogusław

Przemysł Chemiczny

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2021

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T. 100, nr 3

263--267

PL

Zaprezentowano zwięzłą charakterystykę okrzemek z podaniem możliwości ich aplikacji w różnych gałęziach przemysłu.

EN

A review, with 54 refs., of propertions and methods for prod. of SiO₂ structures under lab. and pilot plant conditions.

11

Biocomposites based on a balsa wood core containing intermediate layers made of coconut and sisal

Szatkowski Piotr, Chłopek Jan

Drewno : prace naukowe, doniesienia, komunikaty

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2021

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vol. 64, nr 207

87--100

EN

Sandwich-type composite materials of various geometries were obtained, in which the inner layer was a laminate of glass fabric, and the core consisted of natural materials: balsa wood, coconut and sisal fibres. The materials were tested to determine the type of cracking process under static and dynamic stress conditions (impact strength). The best results were obtained for hybrid balsa/glass fabric composites with a spacer made of sisal mat. This type of system allows a controlled cracking process, which is a consequence of a different stress distribution. The research shows that the combination of different materials in a single composite, depending on their volume fraction, density and layering geometry, opens the way for use in technical constructions, especially where high specific strength is required. The work contains valuable results of research on sandwich materials, their behaviour under load, their modification, and their impact on the transfer of dynamic and static stresses. For the first time, a composition was tested containing a balsa tree core with transient elastic layers made of natural cellulose fibres.

12

Experimental investigations on mechanical properties of walnut shell and pine needle ASH polylactic ACID biocomposites

Chaturvedi Adarsh, Ranakoti Lalit, Kumar Rakesh Pawan, Kumar Mishra Niraj

Composites Theory and Practice

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2021

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R. 21, nr 3

114--120

EN

Biocomposites consisting of polylactic acid reinforced with 2 to 8 wt.% walnut shell and pine needle ash fillers were fabricated by the microwave heating technique. The mechanical properties such as tensile strength, flexural strength, impact strength, Vickers hardness, and sliding wear behavior of the produced biocomposites were examined. The tensile strength declined by 11.62% with a reinforcement of 8 wt.% pine needle ash (PNA) in the PLA matrix as compared to the neat PLA matrix. The flexural strength also dropped by 3.09% with the reinforcement of 8 wt.% PNA in the PLA matrix compared to the neat PLA. It was found that the impact energy was enhanced by 77.27 and 66.67% with the reinforcement of 8 wt.% PNA and WN fillers in the PLA matrix, respectively. The Vickers hardness also improved by 14.54 and 10.35% with the reinforcement of 8 wt.% PNA and WN fillers in the PLA matrix, respectively. In addition, the weight loss due to sliding wear was improved by 95.86 and 94.52% with the reinforcement of 8 wt.% WN and PNA fillers in the PLA matrix as compared to the neat PLA matrix, respectively. The drilling forces (thrust force and torque) were additionally recorded during the drilling process of the PNA and WN filled PLA based biocomposites.

13

The composting of PLA/HNT biodegradable composites as an eco-approach to the sustainability

Czarnecka-Komorowska Dorota, Bryll Katarzyna, Kostecka Ewelina, Tomasik Malgorzata, Piesowicz Elżbieta, Gawdzińska Katarzyna

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2021

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Vol. 69, nr 2

art. no. e136720

EN

The article presents the results of the research related to the decomposition of polylactic acid (PLA)/halloysite nanotube (HNTs) biocomposites into a simple organic form. After manufacturing the nanocomposites, the evaluation of the composting process simulation was conducted using the biodegradation method. First, the selected properties of PLA/HNTs biocomposites, such as density, water absorption, and impact strength were tested. Next, the impact of the composting process on the behavior of PLA/HNTs composites was investigated from 30 to 90 days. Finally, the loss of mass of the composites, hardness, and the structural changes of biocomposites under the composting conditions before and after the composting were evaluated using SEM microscopy. The results showed that the PLA modified by HNT particles has biodegradation-friendly properties and therein is fully suitable for organic recycling. Due to this, in the coming years, it may contribute to the replacement of non-biodegradability polymers, i.e. polyolefins and polyesters, and reduction of plastic packaging wastes.

14

The Optimization of PHBV-hemp Fiber Biocomposite Manufacturing Process on the Selected Example

Frącz Wiesław Jan, Janowski Grzegorz, Bąk Łukasz

Advances in Science and Technology. Research Journal

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2021

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Vol. 15, no 2

127--137

EN

In this work, a modern biocomposite on the base of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) matrix commonly known as PHBV was produced in the extrusion process, containing 30% by weight of hemp fibers. The use of the above-mentioned filler allowed to reduce the producing costs of the composite material compared to pure PHBV, improving, among others, some mechanical properties of products made of this biocomposite while maintaining full biodegradation. The obtained biocomposite can be successfully used for the production of injection molded products, but its processing properties are not yet fully known and consequently it is difficult to obtain the optimal performance properties of the products. As part of this study, the process of optimization of the production process of products from the PHBV-hemp fiber biocomposite was carried out on the example of samples intended for testing in the uniaxial tensile test. By using orthogonal planes, widely used in optimization process, the required number of injection molding tests was reduced. Input data values were determined by the factorial planning method that is commonly used in designing experiments. The calculations were carried out in the Minitab 18 software. Six controlling factors were used in the analyzes, each of which was subject to changes on three levels. When selecting the range of controlling factors, it was initially assumed that for all assumed levels of variability it must be possible to fill the mold cavity completely. The orthogonal plan of the L27 type was used in the research. For the purposes of the method, an orthogonal table was built containing 27 combinations of parameters subject to optimization. Optimization was undertaken for two main criteria: shrinkage of the ,,dog-bone” samples (primary and secondary volumetric shrinkage), mechanical properties (Young's modulus, tensile strength, elongation at break). By means of Taguchi method, a significant improvement of some product mechanical properties made of biocomposite was noted and the effective reduction of the processing shrinkage was observed.

15

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

|

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.

16

Thermally stable biopolymer composites based on poly(3-hydroxybutyrate) modified with linear aliphatic polyurethanes– preparation and properties

Zarzyka Iwona, Czerniecka-Kubicka Anna, Hęclik Karol, Dobrowolski Lucjan, Pyda Marek, Leś Karolina, Walczak Małgorzata, Białkowska Anita, Bakar Mohamed

Acta of Bioengineering and Biomechanics

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2021

|

Vol. 23, no. 2

91--105

EN

Purpose: Poly(3-hydroxybutyrate) (P3HB) is a biopolymer, but storing products from P3HB causes the deterioration of their properties leading to their brittleness. P3HB has also low thermal stability. Its melting point almost equals its degradation temperature. To obtain biodegradable and biocompatible materials characterized by higher thermal stability and better strength parameters than the unfilled P3HB, composites with the addition of polyurethanes were produced. Methods: The morphology, thermal, and mechanical property parameters of the biocomposites were examined using scanning electron microscopy, thermogravimetric analysis, standard differential scanning calorimetry, and typical strength machines. Results: Aliphatic polyurethanes, obtained by the reaction of 1,6-hexamethylene diisocyanate and polyethylene glycols, were used as modifiers. To check the influence of the glycol molar mass on the properties of the biocomposites, glycols with a molecular weight of 400 and 1000 g/mol were used. New biocomposites based on P3HB were produced with 5, 10, 15, and 20 wt. % content of polyurethane by direct mixing using a twin-screw extruder. The following property parameters of the prepared biocomposites were tested: degradation temperature, glass transition temperature, tensile strength, impact strength, and Brinell hardness. Conclusions: Improvement of the processing property parameters of P3HB-biocomposites with the addition of aliphatic polyurethanes was achieved by increasing the degradation temperature in relation to the degradation temperature of the unfilled P3HB by over 30 C. The performance property parameters have also been improved by reducing the brittleness compared to the P3HB, as evidenced by the increase in impact strength and the decrease in hardness with an increase in the amount of polyurethane obtained by the reaction of 1,6-hexamethylene diisocyanate and polyethylene glycol with a molecular weight of 400 g/mol (PU400) as modifier.

17

Biokompozyty polimerowe na bazie polilaktydu i włókien celulozowych

Fabijański Mariusz

Przemysł Chemiczny

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2020

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T. 99, nr 6

923--926

PL

Badano proces wtrysku PLA z różnymi zawartościami włókien celulozowych (dwa typy) w otwartej formie wtryskowej z gniazdem w kształcie spirali Archimedesa. Oznaczono właściwości mechaniczne poszczególnych kompozytów. Stwierdzono, że proces ten nie stwarza problemów technologicznych. Właściwości mechaniczne ulegają pogorszeniu, jednak nie dyskwalifikuje to badanych materiałów do zastosowań, w których wyrób nie jest mocno obciążony mechaniczne.

EN

Two types of cellulose fibers (10-40% by mass) were mixed with polylactide by an open-ended spiral-shaped injection molding. Tensile strength, impact strength and hardness of the composites were detd. The addn. of cellulose fibers resulted in deterioration of all mech. properties of polylactide but the composites can be used in some applications where any high mech. strength of the product is required.

18

Rigid polyurethane foam composites with nut shells

Leszczyńska Milena, Ryszkowska Joanna, Szczepkowski Leonard

Polimery

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2020

|

T. 65, nr 10

728--737

EN

Composites of rigid polyurethane foams were manufactured using ground peanut, hazelnut, walnut and pistachio shells. The aim of this study was the development of environmentally-friendly materials as well as investigation of the influence of the chemical structure, size and morphology of the filler particles on the processing parameters of the developed foams as well as their structure and physico-mechanical and thermal properties. The used fillers were precisely characterised, the viscosity of the polyol premixes have been examined and the characteristic times of the foaming processes have been investigated. The developed materials were studied using the differential scanning calorimetry, thermogravimetry, scanning electron microscopy, infrared spectroscopy and by determination of their apparent density, friability, water absorption and dimensional stability. The presented research results indicate that the agro-food industry waste could be a valuable source of raw materials for the production of rigid polyurethane foam composites.

PL

Kompozyty sztywnych pianek poliuretanowych wytwarzano z zastosowaniem rozdrobnionych łupin orzechów: ziemnych, włoskich, laskowych oraz pistacjowych. Celem pracy było otrzymanie materiałów przyjaznych dla środowiska oraz określenie wpływu budowy chemicznej, wymiarów cząstek i morfologii napełniaczy roślinnych na parametry przetwórcze mieszanek oraz na strukturę i właściwości fizyko-mechaniczne i termiczne wytworzonych pianek. Szczegółowo scharakteryzowano zastosowane napełniacze, określono lepkość przedmieszek poliolowych oraz czasy charakterystyczne dla procesu spieniania. Analizy wytworzonych materiałów dokonano z zastosowaniem różnicowej kalorymetrii skaningowej, termograwimetrii, skaningowej mikroskopii elektronowej, spektroskopii w podczerwieni, a także na podstawie wyznaczonej gęstości pozornej, kruchości, chłonności wody i stabilności wymiarowej. Przedstawione wyniki badań wskazują na duże możliwości wykorzystania odpadów przemysłu rolno-spożywczego do wytwarzania kompozytów sztywnych pianek poliuretanowych.

19

Synthesis and characterization of polymer biocomposites with lignin

Goliszek Marta, Podkościelna Beata

Physicochemical Problems of Mineral Processing

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2019

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Vol. 55, iss. 6

1375--1381

EN

A new method of synthesis of polymer biocomposites with lignin using the photopolymerization method has been proposed. Bisphenol A glycerolate (1 glycerol/phenol) diacrylate (BAGDA) was used as a main monomer and 2-ethylhexyl acrylate (EHA) as a reactive diluent. Lignin (L) was applied as an eco-filler. The influence of the increasing lignin content (0; 2.5; 5; 10; 20% w/w) on the properties of the obtained biocomposites was investigated. The chemical structure of biomaterials was investigated by the attenuated total reflectance Fourier transform infrared spectroscopy (ATR/FT-IR) method while the thermal properties were studied by the differential scanning calorimetry (DSC) and thermogravimetric analysis (TG/DTG). Their hardness was measured by the Shore D method. Incorporation of the biopolymer into the structure of polymer composites could be a promising alternative to synthetic materials and would contribute to better lignin utilization. The results of the study are of practical importance in prospective applications of biocomposites with lignin.

20

pH-dependent composite coatings for controlled drug delivery system — Review

Pawłowski Łukasz, Bartmański Michał, Zieliński Andrzej

Inżynieria Materiałowa

|

2019

|

Vol. 40, nr 3

62--67

EN

Nowadays in case of long-term implants, the most common postoperative complications are bacterial infections, which in consequence may provoke loosening of the implants in the primary phase of stabilization. Bacterial infections are currently the most frequent cause of revision surgery of the implants such as hip joint endoprosthesis, knee joint endoprosthesis and dental implants. In order to provide the local and long-term antibacterial cover in the tissues surrounding the implant, research is performed on materials that are carriers of drugs, which release active substances only in the case of the pH change in the system during inflammation. In consequence, biomaterials ensure antibacterial protection for a long time, not only in short post-operative period. An example of such materials are biopolymers. Biopolymers sensitive to change in pH value of the environment of live tissue that surround the implants can be used as an independent implants or as the coatings on the implants. In this case in the polymer`s matrix is dispersed often used drugs such as doxorubicin, gentamicin, vancomycin and cefuroxime. Drugs are released from this biomaterial according to three main mechanisms: diffusion, swelling and material degradation. This review paper presents the mechanism of bacterial interaction with implant surface and biofilm formation, and mechanism of drugs release from the biological active substance. Therefore, the natural and synthetic polymer materials sensitive to the lower value of pH such as chitosan, Eudragit E 100, Poly (L-histidine) and Poly (4-vinyl pyridine) are described.

PL

W artykule omówiono problem zakażeń bakteryjnych związanych z wszczepieniem biomateriału do organizmu człowieka oraz sposoby ograniczania rozwoju tych zakażeń za pomocą kontrolowanych systemów dostarczania leków, bazując na obszernym przeglądzie najnowszej literatury naukowej.