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1

PLA filament is not equal to PLA filament: Experimental studies of the influence of the type of pigment on the mechanical and thermal properties of poly(lactic acid) products

Iwko Jacek, Jaruga Tomasz, Trzaska Oliwia, Stachowiak Tomasz

Materials Science Poland

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2023

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Vol. 41, No. 1

177-190

EN

The correct manufacture of products using FDM printers is not an easy task, taking into account the value and repeatability of material properties. The properties of elements manufactured in this way depend on many factors, both technological and material. Poly(lactic acid) PLA is one of the most willingly used materials in additive techniques. It is sold in a very wide range of colours. This work was intended to answer the question of how the type of pigment affects the mechanical and thermal properties of products obtained from PLA. The correlation between the material properties and the structure of the material as well as the macroscopic structure of the product has also been investigated. The paper analyses the mechanical and thermal properties of products made of PLA filaments in 12 basic colours obtained from one supplier. Bending, impact strength, HDT and Vicat softening point tests were carried out. The percentage content of residues after calcination the samples was determined. Additional analysis (DSC) was performed to interpret the obtained tests results. They indicate that the mechanical properties differ significantly between different types of PLA with differences of up to 45%. Vicat softening point tests indicate differences of 5°C between the extreme values of these parameters. The DSC interpretive study did not clearly show the reasons for these differences in the properties of the filaments.

2

Research on low density polyethylene (LDPE), recycled by advanced thermal analysis (DSC, TG)

Siwczyk Bartosz, Schlafka Paweł, Sąsiadek Michał, Woźniak Waldemar

International Journal of Applied Mechanics and Engineering

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2023

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Vol. 28, no. 2

113--124

EN

This article presents the issue of recycling and maintaining the processing properties of materials made of plastics. For this purpose, samples from recycled, low-density, polyethylene were tested. The impact of the use of dyes and surface printing on the lifecycles of material and its quality was examined. For this purpose, an analysis was carried out using differential scanning calorimetry and thermos-gravimetry. It was found that the use of dyes may affect the quality of the material and increase the disposal costs of pre-used materials.

3

Thermal analysis of polymeric ionic liquids (using TGA and DSC techniques)

Adamczyk Magda, Masłowska-Lipowicz Iwona, Wyrębska Łucja

Technologia i Jakość Wyrobów

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2022

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R. 67

155--169

EN

The article presents an analysis of the structure stability of polymeric ionic liquids. Using DSC (Differential Scanning Calorimetry) and TGA (Thermogravimetric analysis) techniques, new polymeric ionic liquids containing polyhexamethylene biguanide (PHMB) groups as cations and aryl carboxylate groups as anions derived from benzoic and salicylic acids were studied. The DSC technique measures the heat absorbed or released by the sample during a programmed increase or decrease in temperature. On the other hand, using thermogravimetric measurement (TGA), the so-called thermogravimetric curve, which describes the dependence of the sample mass on temperature. The results obtained during the tests allowed to determine the enthalpy and glass transition temperatures for both samples.

PL

W artykule przedstawiono analizę stabilności struktury polimerycznych cieczy jonowych. Za pomocą technik DSC (Differential Scanning Calorimetry) oraz TGA (Thermogravimetric analysis) zbadano nowe polimeryczne ciecze jonowe zawierające grupy poliheksametylenobiguanidyny (PHMB), jako kationy oraz grupy arylokarboksylanowe, jako aniony pochodzące od kwasu benzoesowego i salicylowego. Technika DSC polega na pomiarze ciepła pochłanianego bądź wydzialnego przez próbkę podczas zaprogramowanego wzrostu lub zmniejszenia temperatury. Natomiast za pomocą pomiaru termograwimetrycznego (TGA) otrzymuje się tzw. krzywą termograwimetryczną, która opisuje zależność masy próbki od temperatury. Rezultaty uzyskane podczas badań pozwoliły na wyznaczenie entalpii oraz temperatur zeszklenia dla obu próbek.

4

Thermal studies of polymer waste and coal sludge

Kijo-Kleczkowska Agnieszka, Gnatowski Adam, Kwiatkowski Dariusz, Szumera Magdalena, Madej Dominika, Leśniak Magdalena, Otwinowski Henryk

Rynek Energii

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2022

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Nr 5

89--96

EN

Plastics are widely used in various industries and households, which has an impact on the condition of the natural environment in terms of waste. Today, the leading plastics’ disposal method is landfilling. It should be emphasized that the production of electricity in Poland is based mainly on hard coal and lignite, which is associated with the continuous production of various types of waste, including post-flotation coal waste (coal sludge). That is why rational waste management, recycling, proper disposal, use, and improvement of the existing and implementation of new technological solutions are crucial for environmental protection. This study undertakes cognitive research on the possibility of using PA6 polyamide waste, marked by high calorific value. Thermal analysis techniques (DSC-TG-QMS) were applied for this purpose. The study includes a comparison of the results of tests conducted for polyamide recyclate, coal sludge, and PA6 recyclate composite with a filler constituting 5% of coal sludge.

PL

W pracy podjęto badania poznawcze nad możliwością wykorzystania odpadów poliamidowych PA6, charakteryzujących się wysoką kalorycznością. Zastosowano w tym celu techniki analizy termicznej (DSC/QMS). W pracy porównano wyniki badań przeprowadzonych dla recyklatu poliamidowego, mułu węglowego i kompozytu z recyklatu PA6 z napełniaczem stanowiącym 5% mułu węglowego.

5

Identyfikacja właściwości termicznych materiałów fazowo zmiennych z dodatkiem wybranych nanomateriałów

Wołoszyn Jerzy

Przemysł Chemiczny

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2022

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T. 101, nr 11

1023--1026

PL

Główną wadą organicznych materiałów fazowo zmiennych, które są coraz częściej stosowane w magazynach energii termicznej, jest ich niska przewodność cieplna. Zmniejszenie oporu cieplnego po stronie medium magazynującego realizowane poprzez dodanie nanomateriałów to jeden ze sposobów na poprawę efektywności procesu wymiany ciepła. Przeprowadzono badania entalpii i temperatury przemiany fazowej, ciepła właściwego oraz czasu przemiany fazowej w trakcie topnienia i krzepnięcia komercyjnie dostępnego materiału fazowo zmiennego z dodatkiem dwóch rodzajów nanoproszków (a-Fe₂O₃ i a-Al₂O₃) o udziale masowym 0,8%, 6,5% oraz 13%. Nie stwierdzono znacznego obniżenia entalpii i temperatury przemiany fazowej dla każdej z przygotowanych próbek. Istotnym negatywnym efektem towarzyszącym przy wzroście udziału nanomateriału był znaczny wzrost czasu przemiany fazowej w trakcie topnienia.

EN

The enthalpy and phase transition temp., sp. heat and phase transition time were detd. during melting and solidification of com. available phase transition material and with the addn. of 2 types of nanopowders (a-Fe₂O₃, a-Al₂O₃) in the amt. of 0.8%, 6.5 % or 13%. No significant decrease in enthalpy and phase transition temp. was observed for each of the prepared samples. A significant neg. effect accompanying the increase in nanomaterial content was a significant extension of the phase transition time during melting.

6

Zastosowanie skaningowej kalorymetrii różnicowej (DSC) w odlewnictwie

Gracz Beata

Laboratorium - Przegląd Ogólnopolski

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2022

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nr specjalny

28--35

PL

Skaningowa kalorymetria różnicowa (DSC) umożliwia stosunkowo szybkie i łatwe badanie materiałów charakteryzujących się różnym stanem skupienia i konsystencją, co zapewnia szerokie spektrum zastosowań badawczych dla przemysłu odlewniczego.

7

The effect of kenaf loading on kenaf/ABS composites structure and thermal properties

Mashelmie S., Rabiatul Manisah M., Bahiyah Baba N., Mohd A.

Journal of Achievements in Materials and Manufacturing Engineering

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2022

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Vol. 111, nr 2

49--56

EN

Purpose: Many manufacturers have recently become interested in using fiber-reinforced polymer composites (FRPs) in structural applications. Synthetic fibres, such as carbon and glass fibres, have been commercialised internationally for decades, but they cause environmental issues because synthetic fibres are non-biodegradable and difficult to recycle once they have served their purpose, potentially polluting the environment. Thus, natural fibre composites like kenaf is a possible replacement for synthetic fibre due to their superior physical and mechanical properties. Kenaf appears to be the best candidate for replacing synthetic fibres in order to accomplish the goal of environmental preservation while also displaying excellent properties such as equivalent specific strength, low density, and renewable resources. Design/methodology/approach: The kenaf fiber was treated in KOH and added to ABS matrix to produce new composites at different loading (10, 15, 20 and 25 wt.%) by using Two Roll Mill machine. The influence of the fiber on the composites properties was evaluated. The produced material was subjected to SEM, MFI, TGA and DSC analysis. Findings: The incorporation of the treated kenaf fiber has an influence on the properties of kenaf/ABS composites. The addition of 10 wt.% kenaf was found to be the best loading with MFI value, initial degradation temperature and glass transition temperature at 0.8208 g/10 min, 322.63°C and 130°C respectively. The fiber was well dispersed in the matrix and shown good adhesion to the ABS. The addition of treated fiber contribute to a reduction in the MFI, improved the thermal stability of the composites and typical effects of Tg of the composite compare to pure ABS. Research limitations/implications: The results suggest the need to continue the study in order to further analyse higher kenaf loading and shed more light on the properties of the composites to improve understanding of kenaf/ABS composites. Originality/value: Obtained results are a solution to alternative of synthetic fibers, which may contribute to the sustainable development of composites materials industry through the utilization of kenaf fiber with ABS matrix.

8

Changes in Thermal Properties of Printouts Made of PETG and PLA Doped with Copper After Electrocorrosive Ageing Process

Redutko Joanna, Kalwik Aleksandra, Szarek Arkadiusz

Archives of Metallurgy and Materials

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2022

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Vol. 67, iss. 1

333--339

EN

The article presents the results of research on selected thermal, mechanical properties, as well as the microscopic structure of filaments and details made on a 3D printer in FDM technology. The materials used in the study were PETG (polyethylene terephthalate doped with glycol) and PLA (polylactide) doped with copper. As part of the study, Differential Scanning Calorimetry (DSC) was performed in order to determine the temperatures of phase transformations and changes in melting enthalpy values of filaments before the printing process and also elements made of them. The second part of the research was electrocorrosive ageing process of printouts, carried out in the Simulated Body Fluid solution in a device generating 0.3 A direct current, voltage with value 4.3 V for the entire duration of the test, which was 720 h. After this process DSC test was conducted again. The next stage of the research was Dynamic Mechanical Analysis (DMA) of printouts before and after electrocorrosive ageing process. This test was carried out to characterize the dynamic-mechanical properties as a function of frequency, temperature and time. Additionally, microscopic analyses of the surfaces of the tested printouts were performed in order to assess the changes after electrolysis.

9

Change of some parameters of UHMWPE depending on the usage

Sobociński Michał, Nabrdalik Marcin

Modelowanie Inżynierskie

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2021

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T. 42, nr 73

48--53

EN

Long-term storage in adverse conditions of polymer materials, initiates ageing process as it affects their useful properties. That process covers all physical and chemical conversions taking place in the structure and effects in conversion of parameters of the material. The subject of this paper was to emphasize changes in some chosen parameters of UHMWPE gained during tests conducted on friction nodes applied in endoprostheses. The frictional – wear tests have been proceeded on samples of UHMWPE paired with contra - samples made of CoCrMo and Ti6Al4V alloys. There have also been conducted Shore’s D hardness tests, as well as DSC analysis. DSC thermograms analysis shows, that the load used at friction – wear tests affected the crystallinity chase and thermal features of polyethylene.

PL

Długotrwałe przechowywanie materiałów polimerowych w niekorzystnych warunkach powoduje inicjowanie procesu starzenia. Proces ten w tym przypadku rozumiany jest jako całokształt przemian fizycznych i chemicznych zachodzących w ich strukturze, wpływających na zmianę właściwości tworzyw polimerowych. Celem pracy było wskazanie zmiany wybranych parametrów UHMWPE zebranych podczas badań prowadzonych nad skojarzeniami węzłów tarcia stosowanymi w endoprotezoplastyce. Badaniom tarciowo - zużyciowym poddano próbki wykonane z UHMWPE współpracujące z przeciwpróbkami wykonanymi ze stopu CoCrMo oraz Ti6Al4V. Przeprowadzono także badania twardości Shore'a D oraz analizę za pomocą różnicowej kalorymetrii skaningowej DSC.

10

Zastosowanie skaningowej kalorymetrii różnicowej (DSC) w odlewnictwie

Gracz Beata

Laboratorium - Przegląd Ogólnopolski

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2021

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nr 2

26--33

PL

Skaningowa kalorymetria różnicowa (DSC) jest jedną z najczęściej stosowanych laboratoryjnych technik analizy termicznej, znajdującą również zastosowanie przemysłowe. Celem niniejszego artykułu jest przedstawienie definicji, podstaw teoretycznych oraz możliwości zastosowania skaningowej kalorymetrii różnicowej w przemyśle odlewniczym. Zaprezentowano w nim wykorzystanie DSC w analizie różnic struktury fazowej odlewów ze stopu AI-Zn-Mg, wykonanych w technologii masy bentonitowej oraz odlewaniu kokilowym.

EN

Differential scanning calorimetry (DSC) is one of the most commonly used laboratory thermal analysis techniques, also finding industrial applications. The aim of this article is to present the definition, theoretical basis and the possibility of applying differential scanning calorimetry in the foundry industry. As an example of application, this article presents the results of the DSC analysis of AI-Zn-Mg alloy cast made in two different types of casting processes (sand mold and permanent mold).

11

Parafina LTP 53/35 jako potencjalny materiał magazynujący ciepło (PCM)

Ksionek Dariusz

Instal

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2021

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nr 11

20--24

PL

W artykule przedstawiono analizę możliwości wykorzystania parafiny LTP 53/35 produkowanej przez firmę Polwax pod kątem jej wykorzystania jako materiału magazynującego ciepło tzw. PCM. Badania wykonano przy użyciu różnicowej kalorymetrii skaningowej DSC, która jest powszechnie wykorzystywana w badaniach materiałów PCM. Potencjał do magazynowania ciepła parafiny określono na podstawie porównania jej z wodą, która jest powszechnie używana w magazynach zarówno ciepła jak i chłodu.

EN

The article contains an analysis of potential to heat storage of paraffin LTP 53/35 Polwax production. For this study one of the thermal analysis methods was used - Differential Scanning Calorimetry (DSC) which is frequently used to study phase change materials. The potential to heat accumulation of the investigated paraffin has been determined in comparison to heat storage potential of water, which is widely used in heat and cold storage.

12

Review of Methods for Testing the Compatibility of High Energy Mixed Components

Gołofit Tomasz, Zakościelny Bartosz, Maksimowski Paweł, Chmielarek Michał, Cieślak Katarzyna, Sałaciński Tomasz

Central European Journal of Energetic Materials

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2021

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Vol. 18, no. 4

512--528

EN

A review of methods for testing the compatibility of high energy mixed components is presented. The advantages, deficiencies as well as the limitations of particular research methods are described based on selected applications reported in the literature. The most frequently used techniques for testing compatibility are thermal methods, such as DSC, TG, VST, and HFC, in which the processes of decomposition of samples conditioned at elevated temperatures are analyzed. Examples of non-thermal methods for testing compatibility, such as DFT, FTIR or XRD are reported in the literature as well. Incompatibility may lead to thermal detonation, which can occur even at low degrees of conversion. For this reason, the authors focused specifically on the limitations of methods for determining compatibility at high degrees of conversion. The methods allowing testing of compatibility based on an analysis for the initial decomposition stage are recommended.

13

Granulation Of Porous Materials with Phase Change Material (PCM)

Bien Tomasz

Budownictwo i Architektura

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2021

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Vol. 20, no 3

135--144

EN

The paper describes the research on the method of production of granulated phase-change materials (PCM) used in construction industry for the accumulation of thermal energy. As mineral materials for the granules preparation zeolite from fly ash Na-P1 and natural diatomite dust were used which were impregnated with paraffinic filtration waste and granulated using a combined granulation method. Obtained granules were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), nitrogen adsorption/desorption isotherm, and differential scanning calorimetry (DSC). Mechanical strength of the materials was determined in a “drop strength” test. Performed analyses revealed that mineral composition and micromorphology of the diatomite and zeolite granules were varied, with zeolite granules having higher mechanical strength.

14

Electrical and thermal properties of anthrone

Kania Sylwester, Kuliński Janusz, Sikorski Dominik

Scientific Bulletin. Physics / Lodz University of Technology

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2020

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Vol. 41

43--51

EN

Electrical and thermal properties of anthrone Quantum-chemical density functional theorem (DFT) calculations indicate that the value of the reorganization energy indicates the possibility of efficient hole capture by the anthrone molecule during transport process of charge carriers. Differential scanning calorimetry (DSC) studies indicate the temperature stability of anthrone molecules above the melting point up to 164°C. The glass transition is determined at 153.7°C and melting point at 157.05°C.

PL

Obliczenia funkcjonału kwantowo-chemicznego (DFT) wskazują, że wartość energii reorganizacji wskazuje na możliwość efektywnego wychwytywania dziur przez cząsteczkę antronu podczas transportu nośników ładunku. Badania metodą różnicowej kalorymetrii skaningowej (DSC) wskazują na stabilność temperaturową cząsteczek antronu powyżej temperatury topnienia do 164°C. Temperaturę zeszklenia określono jako Tg = 153,7°C, a temperaturę topnienia jako Tc = 157,05°C.

15

Właściwości mechaniczne i skład chemiczny uszczelek gumowych

Ambrisko Lubomir, Marasova Daniela, Knapcikova Lucia, Saderova Janka, Cehlar Michal, Khouri Samer

Przemysł Chemiczny

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2020

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T. 99, nr 4

598--601

PL

Badano dwa materiały gumowe przeznaczone do użytku jako uszczelki w zaworach przystosowanych do wysokich temperatur. Właściwości mechaniczne (wytrzymałość, elastyczność, twardość i odporność na ścieranie) badanych materiałów określono dla nowych uszczelek. Skład chemiczny uszczelek określono metodą różnicowej kalorymetrii skaningowej DSC (differential scanning calorimetry). Analiza próbek potwierdziła różnice w składzie badanych uszczelek, co znalazło odzwierciedlenie w ich odmiennych właściwościach mechanicznych.

EN

Two rubber materials intended for valve gaskets operated at high temp. were studied for mech. properties (strength, elasticity, hardness, and abrasion resistance) and by differential scanning calorimetry to det. chem. compn. of the rubber materials. One of the rubber contained ethylene, propylene and vinyl acetate units and the another one ethylene, propylene and butadiene units.

16

Chemical and thermal characteristics of soluble polysaccharides from fruit pericarps of the Algerian Argania spinosa

Hachem Kadda, Boudraa Kamel Eddine, Kaid-Harchea Meriem

Polish Journal of Chemical Technology

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2020

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Vol. 22, nr 4

17--21

EN

Soluble polysaccharides were isolated from fruit pericarps of the Algerian Argania spinosa. The cell wall fraction was subjected to sequential extractions with H2O (2 × 2 h at 100oC), EDTA (1%, 6 h at 80oC) and KOH (1 and 4 M, 14 h at 25oC) . The structures of the obtained polysaccharide fractions were characterized using gas chromatography (GC), infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). The presence of arabinose, galactose and rhamnose in the pectin fractions suggests the presence of rhamnogalacturonan, while the abundance of xylose in the hemicellulosic fractions indicates the presence of xylan. The DSC data revealed the endothermal behavior of all the soluble polysaccharides and only two thermal transitions, the glass transition (Tg) and the fusion transition (Tf) have been recorded.

17

Synthesis and characterization of one-component, moisture curing polyurethane adhesive based on Rokopol® D2002

Wadas Jadwiga, Oliwa Rafał, Pilch-Pitera Barbara, Byczyński Łukasz, Heneczkowski Maciej, Florjańczyk Zbigniew, Plichta Andrzej, Rokicki Gabriel

Polimery

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2020

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T. 65, nr 7-8

568--571

EN

One-part, moisture curing polyurethane (PUR) adhesives based on poly(oxypropylene)diol Rokopol® and 4,4’-diphenylmethylene diisocyanate (MDI) modified with di-isononyl phthalate and a number of inorganic fillers and additives such as carbon black, thixotropic agent, dispersants and dibutyltin dilaurate as curing catalyst were developed. Adhesive curing was followed using dynamic oscillation rheometry and effect of some components on viscoelastic properties of curing materials was discussed. The cured materials were characterized by means of differential scanning calorimetry (DSC) and water contact angle measurements. The adhesive performance of obtained materials in bonding aluminum was evaluated by tensile shear bond strength tests.

PL

Opracowano jednoskładnikowe kleje na osnowie diizocyjanianu 4,4’-metylenodifenylu (MDI) i polioksypropylenodiolu z środkami pomocniczymi (ftalanem diizononylu jako plastyfikatorem, napełniaczami: talkiem, haloizytem, modyfikowanym bentonitem; dyspergatorami, sadzą pigmentową i katalizatorem utwardzania – dilaurynianem dibutylocyny). Proces sieciowania analizowano za pomocą reometru z dynamiczną oscylacją. Metodą różnicowej kalorymetrii skaningowej wyznaczano temperaturę zeszklenia, ponadto określano kąt zwilżania i właściwości adhezyjne otrzymanych materiałów przeznaczonych do łączenia spoin Al/Al.

18

Thermal analysis of matrix composite reinforced with Al2O3 particles

Włodarczyk-Fligier A., Polok-Rubiniec M., Konieczny J.

Journal of Achievements in Materials and Manufacturing Engineering

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2020

|

Vol. 100, nr 1

5--11

EN

Purpose: The aim of this paper is to present a modern manufacturing method of production and compare the thermal, mechanical, properties of composite materials with aluminium alloy matrix reinforced by Al2O3 particles. Design/methodology/approach: The material for investigation was manufactured by the method of powder metallurgy (consolidation, pressing, hot concurrent extrusion of powder mixtures of aluminium EN AW-AlCu4Mg1 (A) and ceramic particles Al2O3). The amount of the added powder was in the range of 5 mass.%, 10 mass.% and 15 mass.%. Findings: The received results concerning the enhancement of hardness, which show the possibility of obtaining the MMC composite materials with required microstructure, influencing the properties of the new elaborated composite materials components. Concerning the thermal properties, especially the linear thermal expansion coefficient was measured, as well as the dilatometric change of the sample length was analysed. Practical implications: Concerning practical implications it can be stated that the tested composite materials can be applied among others in the transportation industry, but it requires additional research. Originality/value: The received results show the possibility of obtaining new composite materials with controlled and required microstructure with possible practical implications.

19

On the Mechanism of Thermal Decomposition of 1,1-Diamino-2,2-dinitroethene (FOX-7) and its Cyclic Derivatives

Krisyuk Boris E., Zakharov Viktor V., Chukanov Nikita V.

Central European Journal of Energetic Materials

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2020

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Vol. 17, no. 1

20--30

EN

The thermal decomposition of 1,1-diamino-2,2-dinitroethene (I) and its cyclic derivatives 2-(dinitromethylene)-1,3-diazacyclopentane (II), 2-(dinitromethylene)-1,3-diazacyclohexane (III) and 2-(dinitromethylene)-1,3-diazacycloheptane (IV) was investigated by quantum chemistry methods (PBE/cc-pVDZ), as well as DSC and TG. According to both the theoretical and experimental data, the thermal stability of compounds I-IV increases in the sequence IV < I ≈ III < II.

20

Study of the Properties and Cells Growth on Antibacterial Electrospun Polycaprolactone/Cefuroxime Scaffolds

Mijovic Budimir, Zdraveva Emilija, Bajsić Emi Govorčin, Slivac Igor, Dekaris Iva, Grgurić Tamara Holjevac, Ferri Tea Zubin

Autex Research Journal

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2020

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Vol. 20, no. 3

312--318

EN

Electrospun materials are good candidates for the design of tissue regeneration scaffolds as they can simulate the natural surroundings of tissue cells. The study proposes electrospun polycaprolactone (PCL)/cefuroxime (CFU) scaffolds for human cell culture and investigates the influence of the antibiotic content on scaffold morphology, thermal and mechanical properties. The increase in the CFU concentration resulted in the reduction of fiber diameter and number of deformations. It also influenced the reduction of scaffold thermal enthalpies and improved scaffold break strength. With regard to cell growth, the scaffolds showed precedence in greater colonization of the HeLa cells. Finally, these scaffolds showed compatibility with standard human cell lines, and thus they can be used for the repair of damaged tissues.