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1

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.

2

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.

3

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.

4

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.

5

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.

6

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.

7

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.

8

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.

9

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.

10

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.

11

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.

12

Rigid polyurethane foam composites with nut shells

Leszczyńska Milena, Ryszkowska Joanna, Szczepkowski Leonard

Polimery

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2020

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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.

13

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.

14

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

Pawłowski Łukasz, Bartmański Michał, Zieliński Andrzej

Inżynieria Materiałowa

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2019

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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.

15

Temperature behaviour of ceramic biocomposites investigated via hot-stage microscopy

Pawlik Justyna, Cholewa-Kowalska Katarzyna

Engineering of Biomaterials

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2019

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Vol. 22, no. 150

22--28

EN

In this study, sol-gel bioactive glasses and β-TCP composites were investigated regarding their thermal behaviour, microstructure, and phase composition. Sol-gel bioactive glasses based on the CaO-SiO2 -P2O5 system of either a high SiO2 content (S2) or a high CaO content (A2) were mixed with the β-TCP at 25:75, 50:50 and 75:25 weight ratios. Basing on the HSM results, i.e. shrinkage curves, densification intervals and characteristic temperatures, the sintering temperatures of composites were indicated. Scanning electron microscopy and X-ray diffraction were used to determine the microstructure and phase composition of composites after sintering at selected temperatures, i.e. 1100°C and 1200°C. The SEM/EDX investigations proved the well-sintered and densified microstructure of the sintered composites. The chemistry of sol-gel bioactive glasses influenced both the thermal beha-viour and the phase composition of the composites. The dominant phases for A2-β-TCP materials were α-TCP, pseudowollastonite and β-TCP, while for S2-β-TCP – cristobalite, β-TCP, and α-TCP. However, the content of each phase varied, depending on the A2 or S2 content in the composite composition. Hot-stage microscopy provides useful information for selecting optimal sintering temperature in order to obtain well-sintered and strengthened material. Moreover, by a carefully selected combination of sol-gel bioactive glasses and β-TCP it is possible to obtain the materials with favorable phase composition with regard to biological activity.

16

Biopolietylen i biokompozyty na jego osnowie

Węgrzyn M., Rudnik E.

Przemysł Chemiczny

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2018

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T. 97, nr 8

1270--1275

PL

Podjęto tematykę polimerów z surowców bioodnawialnych oraz biokompozytów opartych na biopolietylenie. Podano definicje terminów biotworzywa, biopolimery oraz biokompozyty. Szczegółowo opisano biopolietylen i wpływ jego produkcji na środowisko naturalne poprzez ocenę LCA (life cycle assessment). Na podstawie dostępnej literatury zaprezentowano dotychczasowe badania biokompozytów opartych na osnowie z biopolietylenu i różnych dodatkach wzmacniających.

EN

A review, with 40 refs., of bio-based polymers and biobased composite materials (esp. biopolyethylen) in respect to their impact on the environment.

17

Crushing behavior of kenaf fiber/wooden stick reinforced epoxy hybrid "green”composite elliptical tubes

Alkateb M., Sapuan S. M., Leman Z., Jawaid M., Ishak M. R.

Polimery

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2018

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T. 63, nr 6

436--443

EN

In this paper, an investigation on crushing behavior of kenaf fiber/wooden stick reinforced epoxy hybrid composite elliptical tubes is presented. Kenaf fiber reinforced epoxy elliptical composite tubes, unsupported and supported by wooden sticks (4, 6 and 8), were fabricated using hand lay-up process. The crushing tests were performed at a constant speed of 20 mm/s to explore the potential effect of wooden sticks on the specific energy and mechanical behavior of kenaf fiber reinforced epoxy composite elliptical tubes. As a result of the study, it was found that the load carrying capacities of kenaf fiber reinforced epoxy composite tubes were gradually increased with the number of wooden sticks. Generally, the investigation showed that kenaf fiber reinforce depoxy composite elliptical tubes supported by wooden sticks demonstrated superior specific energy absorption and crashworthiness compared to the composite tubes unsupported. Further, the results also revealed that all specimens have failed in longitudinal failure modes. In this regard, an elliptical composite tube supported by 8 wooden sticks exhibited the best energy absorption capability.

PL

Przedstawiono wyniki badań odporności na zgniatanie eliptycznych rur wykonanych metodą laminowania ręcznego z hybrydowych kompozytów żywicy epoksydowej z włóknami kenafu, wzmacnianych 4, 6 lub 8 prętami drewnianymi. Testy zgniatania prowadzono przy stałej szybkości 20 mm/s, w celu oceny potencjalnego wpływu wzmacniających prętów drewnianych na energię właściwą oraz właściwości mechaniczne kompozytów. Stwierdzono, że zdolność do przenoszenia obciążeń przez rury kompozytowe zwiększała się ze wzrostem liczby prętów wzmacniających. Badania wykazały, że wzmocnienie prętami drewnianymi rur eliptycznych z kompozytów żywicy epoksydowej z włóknami kenafu wpływa na zwiększenie zdolności absorpcji energii oraz odporności na zderzenia. Wszystkie próbki ulegały zniszczeniu w kierunku wzdłużnym. Największą zdolność pochłaniania energii wykazywała rura kompozytowa wspierana przez 8 prętów drewnianych.

18

Modification of microcrystalline cellulose filler with succinic anhydride : effect of microwave and conventional heating

Szefer E., Leszczyńska A., Pielichowski K.

Composites Theory and Practice

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2018

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R. 18, nr 1

25--31

EN

In this work the microcrystalline cellulose (MCC) filler was chemically modified by esterification with succinic anhydride(SA) in order to improve the compatibility of MCC with the hydrophobic polymer matrix. The effect of the microwave irradiation and conventional heating on the chemical structure, particle morphology and thermal stability of the cellulosic filler was evaluated by FTIR/ATR, TGA and light microscopy. The extent of surface modification of microcrystalline cellulose gradually increased with an increasing reaction time up to 90 min, and the effect was significantly pronounced under microwave irradiation as compared to conventional heating. A decreasing decomposition temperature was observed for the samples modified with SA as compared to the reference sample as a result of introducing functional side groups into the cellulose backbone and developing the surface of the MCC powder. A decrease in MCC particle sizes was observed as a result of chemical modification, especially under microwave irradiation, indicating partial hydrolysis of the amorphous regions of cellulose in an acidic environment. Smaller particles can be more equally dispersed in a polymer matrix. Applying microwave irradiation enhanced the efficiency of surface modification and produced MCC with a wider range of surface properties. Microcrystalline cellulose with adjusted surface properties can be applied as a reinforcing filler for fully biodegradable ‘green’ composites.

PL

Przedstawiono wstępne badania nad chemiczną modyfikacją mikrokrystalicznej celulozy przez estryfikację bezwodnikiem bursztynowym w celu poprawy jej kompatybilności z hydrofobowymi osnowami kompozytów polimerowych. Określono wpływ prowadzenia syntezy w polu promieniowania mikrofalowego oraz w warunkach ogrzewania konwencjonalnego na strukturę chemiczną, rozmiary cząstek i stabilność termiczną napełniacza celulozowego, stosując metody FTIR/ATR, TGA oraz mikroskopię optyczną. Efektywność estryfikacji MCC bezwodnikiem bursztynowym rosła z czasem reakcji do 90 min i była wyraźnie większa w warunkach pola promieniowania mikrofalowego w porównaniu z ogrzewaniem konwencjonalnym. Obserwowano obniżenie temperatur degradacji modyfikowanej MCC w porównaniu z materiałem niemodyfikowanym na skutek wprowadzenia bocznych grup funkcyjnych w łańcuch celulozy i rozwinięcia powierzchni ziaren MCC. Zmniejszenie rozmiarów ziaren napełniacza na skutek modyfikacji chemicznej, szczególnie w warunkach ogrzewania mikrofalowego, wskazywało na zachodzenie częściowej hydrolizy obszarów amorficznych celulozy w kwaśnym środowisku reakcji. Mniejsze cząsteczki potencjalnie umożliwiają uzyskanie bardziej równomiernej dyspersji napełniacza w osnowie polimeru. Prowadzenie reakcji estryfikacji w warunkach pola mikrofalowego umożliwia uzyskanie napełniacza o większym stopniu zmodyfikowania powierzchni, a przez to wytwarzanie MCC o szerszym zakresie właściwości powierzchniowych i jej zastosowanie jako napełniacza wzmacniającego w całkowicie biodegradowalnych kompozytach polimerowych.

19

Biokompozyty chitozanu z nanometryczną celulozą modyfikowaną kwasem dikarboksylowym

Grząbka-Zasadzińska A., Borysiak S.

Przetwórstwo Tworzyw

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2017

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T. 23, Nr 4 (178)

332--338

PL

Nanometryczną celulozę o dwóch odmianach polimorficznych (CNC I i CNC II), otrzymaną przy użyciu enzymów pochodzących od szczepu bakteryjnego Ochrobactrum anthropi, poddano modyfikacji kwasem pimelinowym. Badania szerokokątowej dyfraktometrii rentgenowskiej (WAXS) oraz spektroskopii w podczerwieni z transformacją Fouriera (FTIR) pozwoliły potwierdzić efektywność odpowiednio konwersji polimorficznej oraz modyfikacji chemicznej materiałów celulozowych. Wszystkie uzyskane napełniacze wykorzystano do wytworzenia kompozytów z chitozanem, które następnie poddano badaniom mechanicznym. Na podstawie zarejestrowanych krzywych rozciągania wyznaczono parametry cech wytrzymałościowych. Otrzymane kompozyty charakteryzowały się bardzo dobrymi właściwościami mechanicznymi. Zawartość 1% zmodyfikowanej CNC I okazała się być najefektywniejsza pod kątem zwiększania wartości modułu Younga oraz naprężenia maksymalnego przy zerwaniu. Zastosowanie modyfikacji chemicznej napełniaczy celulozowych za pomocą kwasu pimelinowego okazało się skuteczne wyłącznie dla materiałów o odmianie polimorficznej celulozy I.

EN

Nanometric celluloses of two polymorphic forms (CNC I and CNC II), obtained using the enzymes coming from Ochrobactrum anthropi bacteria, were chemically modified with pimelic acid. Wide angle X-ray scattering (WAXS) and infrared spectroscopy (FTIR) methods were used to confirm, respectively, supermolecular and chemical structures of cellulosic materials. After characterization nanometric celluloses, both modified and unmodified, were used as fillers for chitosan matrix. The obtained chitosan/nanometric cellulose composites were subjected to tensile tests. Based on the resultant tensile curves, the mechanical parameters were calculated. All the tested composites were characterized with good mechanical properties. However, in terms of Young’s modulus and tensile strength enhancement, addition of 1% of modified CNC I turned out to be optimal. Chemical modification of nanometric cellulose with pimelic acid was found to be effective only for materials with polymorphic form of cellulose I.

20

Rigid polyurethane foam composites with vegetable filler for application in the cosmetics industry

Zieleniewska M., Szczepkowski L., Krzyżowska M., Leszczyński M., Ryszkowska J.

Polimery

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2016

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T. 61, nr 11-12

807--814

EN

This study was designed towards the development of rigid polyurethane foam (RPURF) composites for application in the cosmetics industry using ground hazelnut shell waste as filler. Additionally, the influence of the filler content on the structure of the composites, as well as on their physico-mechanical, thermal, and biological properties was investigated. The particle size distribution and chemical structure of the natural filler, was examined. The synthesized foams were analyzed using a variety of techniques such as infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). Furthermore, the apparent density, water absorption, dimensional stability, compressive strength, and resistance to aging of the materials were determined. Due to the proposed application, the toxicity analysis of the synthesized materials was essential. The conducted research resulted in the development of the composition and preparation procedure for the synthesis of rigid polyurethane foam biocomposites incorporating a high content of ground hazelnut shell as filler.

PL

Otrzymano kompozyty sztywnych pianek poliuretanowych (RPURF) z udziałem odpadowych łupin orzecha laskowego, odpowiednie do zastosowań w przemyśle kosmetycznym. Określono wpływ zawartości napełniacza na strukturę, właściwości fizykomechaniczne, termiczne oraz biologiczne wytworzonych materiałów. Przeanalizowano wymiary cząstek oraz budowę chemiczną napełniacza. Pianki RPURF scharakteryzowano za pomocą spektroskopii w podczerwieni (FT-IR), analizy termograwimetrycznej (TGA), różnicowej kalorymetrii skaningowej (DSC), skaningowej mikroskopii elektronowej (SEM). Ponadto określono gęstość pozorną kompozytów, ich chłonność wody, stabilność wymiarową, wytrzymałość na ściskanie oraz odporność na warunki starzeniowe. Ze względu na przewidywaną aplikację oceniono też toksyczność pianek. Na podstawie wyników badań opracowano skład oraz metodę wytwarzania biokompozytów sztywnych pianek poliuretanowych z dużym udziałem napełniacza pochodzenia naturalnego w postaci zmielonych łupin orzecha laskowego.