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1

Comparative study on the impact transition behaviour of PPS reinforces with 40% VF Glass

Kadhim Rand Fadhil, Jassim Noor Alhuda Sabah, Abdulhasan Maryam Jawad

Diagnostyka

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2023

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Vol. 24, No. 3

art. no. 2023314

EN

Composite materials, in most cases polymers reinforced with fibers, are these days utilized in numerous applications such as aerospace applications in which lightweight, high strength, high specific modulus and low temperature resistance are critical issues. As these materials have possible applications in different designing areas, a lot of work has been put into enhancing their performance. This study's aim was to study the impact transition behavior of PPS and its composite under different ranges of temperatures by investigating their thermal, mechanical and structural characteristics. PPS and its composite reinforced with 40% vf (volume fraction) glass fibers are employed in this study. The impact transition behavior of PPS and 40%Vf glass fibers composite were investigated by analyzing the mechanical properties: impact, tensile, bending and, hardness at the following temperature ranges: 23°C, -26°C, and -78°C. A particular refrigerator and dry ice were used to achieve the extremely low temperatures (-26 C and -78 C, respectively). The results showed that the addition of 40% glass fibers improved the impact transition behavior of 40%GF PPS composite with temperature decreasing. Which with decreasing in temperature from 23˚C to -78˚C, the impact strength of PPS decreased by fifty five percent while it increased by twenty three percent for 40%GF PPS composite.

2

Mechanical and thermal properties of cotton-bamboo fabric/glass fiber epoxy composites

Chandrasekaran Kailasam, Shanmugam Periyasamy, Senthilkumar Palanisamy

Polimery

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2022

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Vol. 67, nr 11-12

567--574

EN

Five-layer epoxy composites consisting of two outer layers made of glass fiber and three inner layers of cotton-bamboo fabric were obtained by compression molding. The influence of cotton-bamboo fabric/glass fiber content (35, 40, 45 and 50 wt%) and the order of stacking laminate layers on the mechanical properties (tensile, flexural, compressive, impact strength), thermal properties (TGA) and structure (FTIR, SEM) of the composites was investigated. The best mechanical and thermal properties were obtained with the content of 45 wt% cotton-bamboo fabric/glass fiber.

PL

Metodą prasowania tłocznego otrzymano pięciowarstwowe kompozyty epoksydowe składające się z dwóch warstw zewnętrznych wykonanych z włókna szklanego oraz trzech wewnętrznych z tkaniny bawełniano-bambusowej. Zbadano wpływ zawartości włókna szklanego (35, 40, 45 i 50% mas) oraz kolejności układania warstw laminatu na właściwości mechaniczne (wytrzymałość na rozciąganie, zginanie i ściskanie oraz udarność), termiczne (TGA) oraz strukturę (FTIR, SEM) kompozytów. Najlepsze właściwości mechaniczne i termiczne uzyskano przy zawartości 45% mas. włókna szklanego.

3

Influence of chemical foaming on the structure and selected properties of glass fiber reinforced PA6

Konczal Natalia, Nowinka Bartosz, Bieliński Marek

Polimery

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2022

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Vol. 67, nr 10

475--482

EN

The effect of the chemical foaming on the structure (SEM) and selected properties of glass fi ber (30, 60 wt%) reinforced polyamide 6 (PA 6) was investigated. Density, tensile properties and Charpy impact strength were determined. Hydrocerol ITP 825 was used as a blowing agent in the amount of 2 wt%. The size of the pores and the foaming degree depended on the distance from the injection point. The smallest pore size (64 μm) was observed for 60 wt% glass fiber reinforced PA6.

PL

Zbadano wpływ procesu spieniania chemicznego na strukturę (SEM) oraz wybrane właściwości poliamidu 6 wzmocnionego włóknem szklanym (30, 60 % mas.). Oznaczono gęstość, właściwości mechaniczne przy rozciąganiu i udarność Charpy’ego. Jako porofor stosowano Hydrocerol ITP 825 w ilości 2% mas. Wielkość porów i stopień spieniania zależały od odległości od punku wtryskiwania. Najmniejszą wielkość porów (64 μm) stwierdzono w przypadku poliamidu zawierającego 60% mas. włókna szklanego.

4

Zbrojenie kompozytowe z włókien szklanych - potencjalne źródło problemów inżynierskich

Błyszko Jarosław

Inżynieria i Budownictwo

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2022

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R. 78, nr 3-4

128--131

PL

W artykule omówiono zastosowanie prętów kompozytowych z włókna szklanego jako alternatywnego sposobu zbrojenia elementów zginanych. Przedstawiono koncepcję zbrojenia minimalnego wyliczanego na podstawie układu sił w przekroju zginanym, a następnie porównano z wynikami badań. Wykazano, że w przypadku zbrojenia GFRP opieranie się jedynie na zależnościach statycznych może prowadzić do zaniżenia nośności.

EN

This paper presents the use of fiberglass composite bars as an alternative reinforcement method for flexural elements. The concept of the minimal reinforcement calculated from the balance of forces in the element is presented and then compared with test results. It is shown that when calculating the minimum degree of GFRP reinforcement, basing only on static relationships can result in too low a load capacity.

5

Investigation of glass fiber influence on mechanical characteristics of natural fiber reinforced poliester composites : an experimental and numerical approach

Mohapatra Deepak Kumar, Deo Chitta Ranjan, Mishra Punyapriya

Composites Theory and Practice

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2022

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R. 22, nr 3

123--129

EN

In the past few decades, natural fiber reinforced polymeric composites have gained significant importance for various structural applications in different sectors like the automotive, aerospace, sports and building construction industries. However, hybridizations make the composite more versatile in term of strength, weight and its processing for many engineering applications. In the current study, a polyester resin matrix was reinforced with two different natural fibers, namely kenaf and palmyra palm leaf stalk (PPLS) and hybridized with glass fiber. Four layers of two different fiber mats, kenaf/glass and PPLS/glass with different stacking sequences were employed to fabricated laminates by the hand lay-up technique. In this case, an attempt was made using the numerical approach to investigate the influence of glass fiber on the mechanical characteristics of the laminates. To substantiate the results of the numerical approach, experiments were conducted. Enhancement of both the tensile and flexural strength was observed due to hybridization of both the kenaf and PPLS fiber with glass fiber. The tensile and flexural strength improved by 68.91 and 37.63% respectively when the kenaf fiber was hybridized with glass fiber. Similarly, enhancement of 54.42% of the tensile strength and 15.92% of the flexural strength were noticed when the PPLS fiber was hybridized with glass fiber. Through the use of ANSYS software, finite element analysis (FEA) was employed as a simulation method to examine the tensile and flexural strength. The numerical findings were found to be quite close to the experimental results, with a variation of less than 3%.

6

Bending Failure Behavior of the Glass Fiber Reinforced Composite I-Beams Formed by a Novel Bending Pultrusion Processing Technique

Zhu Lvtao, Cao Shengbin, Zhang Xiaofeng, Li Lei

Autex Research Journal

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2022

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Vol. 22, no. 2

172--176

EN

The glass fiber reinforced resin matrix composite I-beams were designed and formed via a type of novel bending pultrusion processing technique, and the three-point bending tests were carried out to analyze the mechanical bending performances. The obtained results show that the main failure mode of the composite I-beam under the bending load is the upper structure (top flange) cracks along the length direction of the fibers, and the cracks simultaneously propagate downwards in the vertical direction. The bifurcated cracks can be found at the junction area between the top flange and web. In addition, the main bending failure mechanism of the composite I-beam includes the matrix cracking, propagation of cracks, and final fracture failure. In particular, noting that when the crack reaches the I-shaped neck position, the lateral bifurcation occurs, and the resulting secondary cracks further extend in two directions, which leads to the serious damage between the top flange and web, and the ultimate fracture failure occurs.

7

Measurement and evaluation of delamination factors and thrust force generation during drilling of multiwall carbon nanotube (MWCNT) modified polymer laminates

Kumar Kuldeep, Verma Rajesh Kumar

Archive of Mechanical Engineering

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2022

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LXIX, nr 2

269--300

EN

In recent years, manufacturing industries have demanded high-performance materials for structural components development due to their reduced weight, improved strength, corrosion, and moisture resistance. The outstanding performance of polymer nano-composites substitutes the use of conventional composites materials. This study is concerned with the machining of MWCNT and glass fiber-modified epoxy com posites prepared by a cost-effective hand layup procedure. The investigations were carried out to estimate the generation of the thrust force (Th) and delamination factors at entry (DFentry) and exit (DFexit) side during the drilling of fiber composites. The effect of varying constraints on the machining indices was explored for obtaining an adequate quality of hole created in the epoxy nano-composites. The outcome shows that the feed rate (F) is the most critical factor influencing delamination at both entry and exit side, and the second one is the thrust force followed by wt.% of MWCNT. The statistical study shows that optimal combination of S (1650 Level-2), F (165 Level-2), and 2 wt.% of MWCNT (Level-2) can be used to minimize DFentry, DFexit, and Th. The drilling-induced damages were studied by means of a high-resolution microscopy test. The results reveal that the supplement of MWCNT substantially increases the machining efficiency of the developed nano-composites.

8

Thermal gravimetric analysis of glass fiber reinforced composite for understanding the impact of copper oxide in relation to titanium oxide filler particles

Alam Shahinoor, Chowdhury Mohammad Asaduzzaman

Composites Theory and Practice

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2021

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R. 21, nr 1-2

12--21

EN

In this work, the composite samples required to investigate their thermal properties were fabricated employing the conventional hand lay-up technique, followed by a light compression molding process. A fixed weight of plain woven glass fiber and epoxy with four different types of fillers as calcium carbonate (CaCO3), aluminum oxide (Al2O3), magnesium oxide (MgO) and titanium oxide (TiO2) or copper oxide (CuO) of different weights (5, 10 and 15 g) were studied. According to thermal gravimetric analysis (TGA), it was observed that the melting point (Tm) and glass-transition temperature (Tg) are affected by the presence of CuO and TiO2, which indicate the degree of composite crystallinity established by the stronger interfacial interaction by the CuO than that of the TiO2 particles and the amorphous region of the chain. These studies were supported by examination of the surface morphology of the composites by means of scanning electron microscopy (SEM).

9

Analysis of Basis Weight Uniformity Indexes for the Evaluation of Fiber Injection Molded Nonwoven Preforms

Moll Patrick, Wang Shaofan, Coutandin Sven, Fleischer Jürgen

Autex Research Journal

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2021

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Vol. 21, no. 3

341--351

EN

Fiber injection molding is an innovative approach for the manufacturing of nonwoven preforms but products currently lack a homogeneous fiber distribution. Based on a mold-integrated monitoring system, the uniformity of the manufactured preforms will be investigated. As no universally accepted definition or method for measuring uniformity is accepted yet, this article aims to find a suitable uniformity index for evaluating fiber injection molded nonwovens. Based on a literature review, different methods are implemented and used to analyze simulated images with given distribution properties, as well as images of real nonwovens. This study showed that quadrant-based methods are suitable for evaluating the basis weight uniformity. It has been found that the indexes are influenced by the number of quadrants. Changes in sample size do not affect the indexes when keeping the quadrant number constant. The quadrants-based calculation of the coefficient of variation showed the best suitability as it shows good robustness and steady index for varying degrees of fiber distribution.

10

Durability performance of fibrous high-performance cementitious composites under sulfuric acid attack

Mermerdaş Kasım, Ipek Süleyman, Anwer Ahmed Motesem, Ekmen Şevin, Özen Mustafa

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 4

203--222

EN

The high-strength concrete having a better compressive strength demeanor can be manufactured by the addition of the fibers which eliminates the inherent weakness, the brittle failure due to lack of tensile strength. In this study, an experimental study covering the enhancement of the mechanical characteristics and the investigation of the performance against the aggressive acid attack of high-performance cementitious composites (HPCC). For this, steel and glass types of fiber were employed in the manufacturing of HPCC, as either single or hybrid at various levels. The HPCC mixtures were designed at a constant water-to-cementitious ratio of 0.25. Portland cement and microsilica were employed in the manufacturing as cementitious material whereas the aggregate was the mix of river and quartz sands. 14 HPCC mixtures were designed and the flowability, unit weight, compressive and flexural strengths, sorptivity index, ultrasonic pulse velocity were tested at various ages. Besides, the loss in the strength, mass, and dimension of HPCC mixtures was also measured after exposure of the mixtures 1- and 2-month aggressive sulfuric acid (H2SO4). Additionally, the experimental results were statistically evaluated through general linear model ANOVA. Based on the results, the highest compressive strength values were observed in the HPCC mixture manufactured with steel fiber. The lowest losses in both flexural and compressive strengths were observed in the mixtures produced with microsilica. Steel fiber addition increased the compressive strength not only after applying the normal curing regime but also after exposing the sulfuric acid. Both flexural and compressive strength of HPCC mixtures were influenced by fiber type and volume fraction. The addition of glass fiber decreased compressive strength.

11

Phenol-formaldehyde resin composites filled with modified phlogopite reinforced with hybrid glass and basalt fiber meshes used as grinding wheels

Oleksy Mariusz, Oliwa Rafał, Bulanda Katarzyna, Szałajko Robert, Budzik Grzegorz, Skrzypczak Izabela

Polimery

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2020

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T. 65, nr 11-12

833--837

EN

The research on obtaining composites based on phenol-formaldehyde resin (PFR) with modified phlogopite quaternary ammonium salt (QAS) reinforced with hybrid glass and basalt fiber was carried out. The influence of the reinforcement structure (glass mesh weave) and the type of fiber on the performance properties of the obtained composites were assessed, especially in terms of their use a grinding wheels reinforced with modified hybrid glass and basalt fiber meshes. Based on the obtained research results, it was found that composites reinforced with a glass fiber layer mesh with a matrix of phenol-formaldehyde resin filled with modified phlogopite are characterized by higher mechanical strength, abrasion resistance and dynamic strength of the disk compared to unmodified composites.

PL

Przeprowadzono badania nad otrzymaniem kompozytów na osnowie żywicy fenolowo-formaldehydowej (PFR) z flogopitem zmodyfikowanym czwartorzędową solą amoniową (QAS) wzmacnianych hybrydowymi siatkami z włókna szklanego i bazaltowego. Oceniono wpływ struktury wzmocnienia (splotu siatki szklanej) oraz rodzaju włókna na właściwości użytkowe otrzymanych kompozytów, zwłaszcza w kontekście ich zastosowania w charakterze ściernic. Na podstawie uzyskanych wyników badań stwierdzono, że kompozyty wzmocnione siatką warstwową z włókna szklanego z osnową żywicy fenolowo-formaldehydowej napełnionej zmodyfikowanym flogopitem charakteryzują się większą wytrzymałością mechaniczną, odpornością na ścieranie oraz wytrzymałością dynamiczną tarczy niż kompozyty niemodyfikowane.

12

Influence of fiber reinforcement towards the physical characteristics of low density polyethylene laminated composites

Ravichandran S., Raj A. Daniel, Visvanath P. Balaji, Mohammad Faruq, Al-Lohedan Hamad A., Sagadevan Suresh

Polimery

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2020

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T. 65, nr 6

449--457

EN

In recent years, the increased interest in the design and fabrication of lightweight polymer composites with various combinations and stoichiometry is due to their enhancement of electrical, mechanical, thermal, and biological properties compared to the properties of conventional materials. With that view, the present study deals with the effects of low density polyethylene composites (LDPE) reinforced with epoxy resin, glass fiber, carbon fiber, and Kevlar towards the mechanical, thermal, and water absorption properties. The mechanical studies showed that the LDPE composite reinforced carbon fiber has the best tensile properties compared to other composites and this can be mostly due to the proper bonding and associated interaction between the polymeric matrix and the bidirectional layer of the fibers. Also, the carbon fiber reinforced composite has superior properties of impart energy compared to the other composites and the non-reinforced ones and this is attributed to the crystalline nature of carbon fiber. Further studies of the thermal properties indicated that the retention of thermal stability for all the fiber-reinforced polymer composites, while the water absorption revealed a considerable increase in the weight of Kevlar fiber-reinforced composite. From the overall analysis, the enhanced properties of LDPE matrix reinforced fibers are linked to the morphological changes that occurred and are directly affected by the nature of the fiber.

PL

Zwiększone w ostatnich latach zainteresowanie projektowaniem i wytwarzaniem lekkich kompozytów polimerowych wynika z ich lepszych właściwości elektrycznych, mechanicznych, termicznych i biologicznych w porównaniu z cechami materiałów konwencjonalnych. Zbadano wpływ rodzaju wzmocnienia (włókno szklane, włókno węglowe i włókno Kevlar) na właściwości mechaniczne, termiczne i absorpcję wody laminatowych kompozytów polietylenu małej gęstości (LDPE) z żywicą epoksydową. Stwierdzono, że kompozyt LDPE z włóknem węglowym, w porównaniu z innymi kompozytami, wykazuje najlepszą wytrzymałość na rozciąganie, co może wynikać głównie z interakcji polimerowej osnowy z dwukierunkową warstwą włókien. Ponadto kompozyt ten ma większą zdolność przenoszenia energii niż pozostałe badane kompozyty, co można przypisać krystalicznej budowie włókna węglowego. Badania właściwości termicznych wykazały stabilność termiczną wszystkich kompozytów polimerowych wzmocnionych włóknami oraz znaczną absorpcję wody kompozytu wzmocnionego włóknem Kevlar.

13

Seismic strengthening of nonductile bridge piers using low-cost glass fiber polymers

Rodsin K., Hussain Q., Joyklad P., Nawaz A., Fazliani H.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2020

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Vol. 68, nr 6

1457--1470

EN

Several recent earthquakes have indicated that the design and construction of bridges based on former seismic design provisions are susceptible to fatal collapse triggered by the failure of reinforced concrete columns. This paper incorporates an experimental investigation into the seismic response of nonductile bridge piers strengthened with low-cost glass fiber reinforced polymers (LC-GFRP). Three full-scale bridge piers were tested under lateral cyclic loading. A control bridge pier was tested in the as-built condition and the other two bridge piers were experimentally tested after strengthening them with LC-GFRP jacketing. The LC-GFRP strengthening was performed using two different configurations. The control bridge pier showed poor seismic response with the progress of significant cracks at very low drift levels. Test results indicated the efficiency of the tested strengthening configurations to improve the performance of the strengthened bridge piers including crack pattern, yield, and ultimate cyclic load capacities, ductility ratio, dissipated energy capacity, initial stiffness degradation, and fracture mode.

14

Research on impact of reducing energy consumption of processing on thermal and mechanical properties of polyacetal composites with glass fibers, by lowering process temperature

Kwiatkowski Dariusz, Gnatowski Adam, Kijo-Kleczkowska Agnieszka, Otwinowski Henryk

Rynek Energii

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2019

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Nr 5

80--84

EN

The production of polyacetal composites is justified by the numerous advantages of the methods of their production, the possibility of mixing during processing, extended possibilities of their use and operating conditions. Changing the temperature of the processing entails a change in the thermal and mechanical properties of these materials. Anticipation of changes in properties due to lower energy consumption of process by lowering the processing temperature plays a big role in the composition planning as well as in the preparation of polymer composites. The article discusses the results of investigations on the impact of filler in the form of glass fiber and processing temperature on selected properties of polyacetal composites with a content of 10 and 30% glass fiber. The tests included mechanical properties and thermal analysis. Mechanical properties such as tensile strength, hardness and impact resistance were determined. The degree of crystallinity was investigated by DSC and the melting range of the crystalline phase was determined. The tests were carried out for polyacetal named Tarnoform and two composites on its matrix, with 10 and 30% glass fiber content. The effect of lowering the mold temperature on the tested properties of both polyacetal and composites with the addition of glass fiber was determined. Changes in the tensile strength, hardness and impact strength values of the tested materials for the samples under varying temperature conditions of the process were observed. In the conducted tests, changes in mechanical properties were registered. for composites formed at a lower temperature of the mold for both polyacetals and composites with the addition of fiberglass. The character of the changes in the value of the tested properties is similar for the composites produced with the temperature of the mold. The influence of mold temperature decrease on the degree of crystallinity of polyacetal was observed, and to a lesser extent for composites. The effect of lowering the processing temperature on the melting range of the crystalline phase of the polymer was determined, the narrowing of the crystalline phase melting range in the case of polyacetal was observed, at reducing of the mold temperature, and small constriction for the composites.

PL

Wytwarzanie kompozytów poliacetalu jest uzasadnione licznymi zaletami metod ich wytwarzania, możliwości przeprowadzenia mieszania podczas przetwórstwa, rozszerzonymi możliwościami ich wykorzystania i warunkami eksploatacji. Zmiana parametrów temperaturowych procesu przetwórstwa pociąga za sobą zmianę właściwości termicznych i mechanicznych tych materiałów. Przewidywanie zmian właściwości na skutek obniżenia energochłonności procesu poprzez obniżenie temperatury przetwórstwa odgrywa dużą rolę w planowaniu składu jak również w sporządzaniu kompozytów polimerowych. W artykule omówiono wyniki badań wpływu napełniacza w postaci włókna szklanego oraz temperatury przetwórstwa na wybrane właściwości kompozytów poliacetalu o zawartości 10 i 30% włókna szklanego. Badania obejmowały właściwości mechaniczne oraz analizę termiczną. Wyznaczono takie właściwości mechaniczne jak: wytrzymałość na rozciąganie, twardość i udarność. Zbadano stopień krystaliczności metodą DSC oraz określono zakres temperatury topnienia fazy krystalicznej. Określono wpływ obniżenia temperatury formy na badane właściwości zarówno poliacetalu jak i kompozytów z dodatkiem włókna szklanego. Zaobserwowano zmiany wartości wytrzymałości na rozciąganie, twardości i udarności badanych materiałów dla próbek przy zmiennych warunkach temperaturowych procesu. W przeprowadzonych badaniach zarejestrowano zmiany właściwości mechanicznych. dla kompozytów wytworzonych przy niższej temperaturze formy zarówno dla poliacetalu jak i kompozytów z dodatkiem włókna szklanego. Charakter zmian wartości badanych właściwości jest podobny dla wytworzonych kompozytów przy zmiennej temperaturze formy. Zarejestrowano wpływ zmniejszenia temperatury formy na stopień krystaliczności poliacetalu, a w mniejszym stopniu dla kompozytów. Określono wpływ obniżenia temperatury przetwórstwa na zakres topnienia fazy krystalicznej polimeru, przy czym zarejestrowano zwężenie zakresu topnienia fazy krystalicznej w przypadku poliacetalu przy zmniejszeniu temperatury formy, a niewielkie zwężenie dla kompozytów.

15

Mechanical properties of sugar palm yarn/woven glass fiber reinforced unsaturated polyester composites: effect of fiber loadings and alkaline treatment

Mohd Nurazzi N., Khalina A., Sapuan S. M., Ilyas R. A.

Polimery

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2019

|

T. 64, nr 10

665--675

EN

In this paper, hybrid sugar palm yarn and glass fiber reinforced unsaturated polyester composites were investigated in relation to the effects of fiber loadings and alkaline treatment on the composite mechanical properties, such as tensile, flexural, impact and compression strength. The composites were fabricated at a weight ratio of matrix to reinforcement of 70 : 30 and 60 : 40, respectively, while the ratio of sugar palm yarn fiber to glass fiber was selected at 70 : 30, 60 : 40 and 50 : 50, respectively. The results revealed that the mechanical properties of the hybrid composites were increased with an increase of glass fiber loading for both 30 wt % and 40 wt % reinforcement content. The alkaline treatment of the sugar palm fibers have advantageous effect on the hybrid composite performance. The overall results indicated that the developed hybrid composites can be used as an alternative material for glass fiber reinforced polymer composites for various structural applications.

PL

Zbadano wpływ zawartości włókien i ich obróbki alkalicznej na właściwości mechaniczne wzmacnianych włóknem szklanym kompozytów nienasyconej żywicy poliestrowej z włóknami palmy cukrowej. Oceniano wytrzymałość kompozytów na rozciąganie, zginanie, uderzenie i ściskanie. Wytworzone kompozyty zawierały 30 oraz 40% mas. włókien, przy stosunku masowym włókien palmy cukrowej do włókien szklanych 70/30, 60/40 i 50/50. Stwierdzono, że wytrzymałość mechaniczna kompozytów hybrydowych zwiększa się ze wzrostem zawartości włókna szklanego, a obróbka alkaliczna włókien palmy cukrowej wywiera korzystny wpływ na właściwości zawierających ją kompozytów hybrydowych. Uzyskane wyniki wskazują, że opracowane kompozyty hybrydowe mogą być stosowane jako materiał alternatywny dla kompozytów polimerowych wzmacnianych jedynie włóknem szklanym.

16

Fire resistant glass fabric-epoxy composites with reduced smoke emission

Oliwa Rafał, Oleksy Mariusz, Oliwa Joanna, Węgier Aleksandra, Krauze Sławomir, Kowalski Maciej

Polimery

|

2019

|

T. 64, nr 4

290--293

EN

In this article a preparation method of epoxy resin/glass fabric composites with reduced flammability and smoke emission was presented. For this purpose the two groups of powder-epoxy compositions containing: (1) melamine polyphosphate (MPP) and aluminum diethyl phosphinate (AlDPi); (2) ammonium polyphosphate (APP) and dipentaerythritol (DPE) were used as matrices in six-ply glass fabric reinforced composites. The flame retardants content was 25 wt %. In addition, the 10–15 wt % of zinc borate (ZB) as a smoke reducing agent was added to each compositions. The flame resistant and smoke emission of prepared laminates designed for application in public transport components were evaluated. It was found that with the increase of zinc borate content, the emission of fumes decreased. The lowest maximum of specific optical density (Dsmax = 312.2), specific optical density in the first 4 minutes of the test [Ds(4) = 304.1] and cumulative specific optical densities in the first 4 minutes of the test (VOF4 = 707.6 min) have been achieved for composite containing 10 wt % of MPP, 15 wt % of AlDPi and 15 wt % of ZB. Furthermore, this composite was characterized by V0 class by UL94 test, limiting oxygen index LOI = 36.8 % and maximum average rate of heat emission MAHRE = 80 kW/m2.

PL

Na osnowie z proszkowej żywicy epoksydowej otrzymywano kompozyty wzmocnione tkaniną szklaną, charakteryzujące się zwiększoną odpornością na płomień oraz zmniejszoną emisją dymów. Przygotowano dwie grupy kompozycji epoksydowych: (1) polifosforanu melaminy (MPP) idietylofosfinianu glinu (AlDPi); (2) polifosforanu amonu (APP) i dipentaerytrytu (DPE), które wykorzystano jako osnowy w sześciowarstwowych kompozytach wzmocnionych tkaniną szklaną. Zawartość uniepalniaczy wynosiła 25 %mas. W celu zmniejszenia intensywności wydzielania dymów do kompozycji wprowadzano też 10–15 % mas. boranu cynku (ZB). Wyniki badań potwierdziły, że wraz ze zwiększaniem zawartości boranu cynku zmniejsza się emisja dymów zbadanych materiałów. Najmniejsze wartości: maksymalnej właściwej gęstości optycznej (Dsmax = 312,2), właściwej gęstości optycznej po 4 minutach badania [Ds(4) = 304,1] oraz łącznej wartości właściwych gęstości optycznych w pierwszych 4 minutach badania (VOF4 = 707,6 min) wykazywał kompozyt wytworzony z 10 % mas. MPP, 15 % mas. AlDPi oraz 15 % mas. ZB. Kompozyt ten charakteryzował się klasą palności V0 wg testu palności UL94, indeksem tlenowym LOI = 36,8 % oraz maksymalną średnią szybkością emisji ciepła MAHRE = 80kW/m².

17

Examinations of structure and properties of polymer composite with glass fiber

Caban Renata

Composites Theory and Practice

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2019

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R. 19, nr 4

150--156

EN

The article discusses the results of research on the structure and mechanical properties of polypropylene composites with glass fiber. The samples for the examinations were made using a Krauss-Maffei (KM65 - 160C1) screw injection molding machine. The investigations encompassed composites with a polypropylene matrix which contained 30 and 50% glass fiber (GF). Part of the material was processed by heat treatment in the form of annealing. The crystal structure of the samples was analyzed on a wide-angle X-ray diffractometer - Seifert 3003 T-T. In most of the obtained diffraction patterns a few strong diffraction reflexes can be seen. They were identified as reflections derived from polypropylene polymorphs: α (monoclinic), β (hexagonal) and from the smectic phase of polypropylene. Dynamic mechanical analysis (DMA) tests were performed on a DMA 242 Netzsch instrument under the mode of a 3-point bending clamp with an oscillatory frequency of 3.0 Hz. The transition to the glassy state is the most evident for polypropylene. In the case of polypropylene composites, the transition to the glassy state is less evident. The largest tendency of the storage modulus value as a function of temperature to decrease was noted for polypropylene and the smallest for the polypropylene composite with a 50% glass fiber content. Higher values of storage modulus E′ were noted after annealing. For all the samples, glass transition temperature Tg decreases after annealing. Investigations of the mechanical properties of the studied composites were also performed: tensile strength testing, Young's modulus, hardness and impact test. In each case the addition of glass fiber caused an increase in mechanical properties. More over, it can be noted that the values of the mechanical properties of PP/GF composites after annealing are higher than those of PP/GF composites before annealing. Both the Vicat softening temperature as well as heat deflection temperature are higher for the samples after annealing. SEM micrographs show the mechanism of breakage of the glass fibers and damage of the matrix material. During observation of the fractures, no significant fiber pullout from the polymer matrix was noted. This demonstrates the good adhesion of the glass fiber to the matrix.

PL

Omówiono wyniki badań struktury i właściwości mechanicznych kompozytu polipropylenu z włóknem szklanym. Próbki do badań wykonano na wtryskarce ślimakowej Krauss - Maffei (KM65 - 160C1). Badaniom poddano kompozyty na osnowie polipropylenu, które zawierały 30 i 50% włókna szklanego. Część materiału poddano obróbce cieplnej polegającej na wygrzewaniu. Strukturę krystaliczną próbek analizowano na dyfraktometrze rentgenowskim Seifert 3003 T-T. Na większości otrzymanych dyfraktogramach można zaobserwować kilka silnych refleksów dyfrakcyjnych. Zidentyfikowano je jako refleksy pochodzące od odmian polimorficznych polipropylenu: α (jednoskośna), β (heksagonalna) oraz fazy smektycznej polipropylenu. Dynamiczne właściwości mechaniczne kompozytów na osnowie polipropylenu badano na aparacie do badań dynamicznych DMA 242 firmy Netzsch. Przejście w stan szklisty jest najbardziej widoczne dla polipropylenu. W przypadku kompozytów polipropylenu przejście w stan szklisty jest mniej widoczne. Największą tendencję obniżenia wartości modułu zachowawczego w funkcji temperatury odnotowano w przypadku polipropylenu, a najmniejszą w przypadku kompozytu polipropylenu zawierającego 50% włókna szklanego. Po wygrzewaniu zauważono wyższe wartości modułu zachowawczego. Dla wszystkich próbek zarejestrowano obniżenie wartości temperatury zeszklenia Tg po wygrzewaniu. Wykonano również bada-nia właściwości mechanicznych: wytrzymałość na rozciąganie, moduł Younga, twardość i udarność. W każdym przypadku wraz ze wzrostem zawartości włókna szklanego w kompozycie wzrastają własności mechaniczne. Ponadto, wygrzewanie prowadzi do uzyskania korzystniejszych właściwości mechanicznych badanych kompozytów. Zarówno temperatura mięknienia wg Vicata, jak i wartości temperatury pod obciążeniem (HDT) są wyższe dla próbek po wygrzewaniu. Mikrofotografie SEM przedstawiają mechanizm uszkodzenia włókien szklanych oraz materiału osnowy. Podczas obserwacji przełomów nie zauważono znaczącego wyciągania włókien z polimerowej osnowy. Świadczy to o dobrej adhezji włókien szklanych z polimerową osnową.

18

Chitosan Modified Corn Starch and Its Application as a Glass Fibre Sizing Agent

Wang Y., Li J., Li H., Wang X., Lei H., Huo J.

Fibres & Textiles in Eastern Europe

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2017

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Vol. 25, no. 3 (123)

112--120

EN

Chitosan-modified corn starch was prepared and then applied as a glass fiber sizing agent. The effect of the chitosan on starch-based emulsion, film and sized glass fiber was studied. When 5 % of the chitosan was added, the overall performance of the modified film-forming agent was optimal. The viscosity, surface tension and zeta potential of the sizing agent were 44.99 mPa·s, 51.29 mN·m-1 and 4.5 mV, respectively. The modified sizing agent could easily spread over the surface of glass fibre, and conglutinated to the glass surface firmly. The tensile strength and stiffness of modified-starch glass fiber reached 0.43 N·tex-1 and 4.96 cm. Glass fiber with good overall performance was obtained.

PL

W pracy przygotowano skrobię kukurydzianą modyfikowaną chitozanem, a następnie zastosowano ją jako środek klejący włókien szklanych. Określono lepkość, napięcie powierzchniowe i potencjał zeta środka klejącego. Zmierzono wytrzymałość na rozciąganie i sztywność zmodyfikowanego włókna szklanego. Stwierdzono, że modyfikacja skrobi chitozanem powoduje poprawienie jej właściwości jako środka klejącego. Modyfikacja zwiększyła przyczepność skrobi do włókien i poprawiła ich właściwości mechaniczne.

19

Polylactide-based composites reinforced with biodegradable glass fibers

Markiewicz G., Dąbrowski J. R., Kochanowicz M., Żmojda J., Jałbrzykowski M.

Engineering of Biomaterials

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2017

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Vol. 20, no. 143 spec. iss.

24

EN

This paper presents the method of obtaining biodegradable glass fibers and the results of strength tests of polylactide based composites reinforced with obtained fibers. Polylactide (PLA) is a biodegradable plastic used in both industry and medicine. In medical applications its use is limited due to low mechanical properties. One of the methods to improve the strength parameters is the development of composite materials based on PLA with fibrous fillers. In this work as a matrix, the NatureWorks 4043D polylactide was used. For the reinforcement, the continuous, biodegradable glass fiber was used. These fibers were obtained by direct pulling out of the preform. Their composition is based on the composition of the biodegradable 45S5 glass, but the contents of calcium oxide (CaO) and sodium oxide (Na2O) have been changed. Also the potassium oxide (K2O) was added. Composite samples were obtained by flooding the fibers with polylactide dissolved in dichloromethane. Strength tests were carried out using the Zwick/Roell Z010 strength machine. The tensile strength values for composites ranged from slightly less than 11 MPa to almost 20 MPa. For PLA samples it ranged from about 14 MPa to slightly less than 18 MPa. The highest values of tensile strength were obtained by composite samples. Initial studies show that it is possible to improve the tensile strength of PLA samples by incorporating biodegradable glass fibers into their structure.

20

Thermal Aging of Unsaturated Polyester Composite Reinforced with E-Glass Nonwoven Mat

Hossain M., Elahi A. H. M. F., Afrin S., Mahmud I., Cho H. M., Khan M. A.

Autex Research Journal

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2017

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Vol. 17, no. 4

313--318

EN

An experiment was carried out using glass fiber (GF) as reinforcing materials with unsaturated polyester matrix to fabricate composite by hand layup technique. Four layers of GF were impregnated by polyester resin and pressed under a load of 5 kg for 20 hours. The prepared composite samples were treated by prolonged exposure to heat for 1 hour at 60-150°C and compared with untreated GF-polyester composite. Different mechanical test of the fabricated composite were investigated. The experiment depicted significant improvement in the mechanical properties of the fabricated composite resulted from the heat treatment. The maximum tensile strength of 200.6 MPa is found for 90°C heat-treated sample. The mechanical properties of the composite do seem to be very affected negatively above 100°C. Water uptake of the composite was carried out and thermal stability of the composite was investigated by thermogravimetric analysis, and it was found that the composite is stable up to 600°C. Fourier transform infrared spectroscopy shows the characteristic bond in the composite. Finally, the excellent elevated heat resistant capacity of glass-fiber-reinforced polymeric composite shows the suitability of its application to heat exposure areas such as kitchen furniture materials, marine, and electric board.