Wyniki wyszukiwania - BazTech

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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.

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Epoksydacja związków allilowych nadtlenkiem wodoru w obecności katalizatorów tytanowo-silikalitowych

Wróblewska A.

Prace Naukowe Politechniki Szczecińskiej. Instytut Technologii Chemicznej Organicznej

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2008

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Nr 608 (5)

5-116

EN

The results for epoxidation of allylic compounds: allyl alcohol, methallyl alcohol, methallyl chloride, 2-buten-1-ol and 1-buten-3-ol with 30% hydrogen peroxide were presented. The epoxidations were performed over earlier obtained titanium silicalite catalysts: microporous (TS-1, TS-2 and Ti-Beta) and mesoporous (Ti-MCM-41 and Ti-MCM-48). There were applied two methods of epoxidation: at increased pressure (autogenic pressure) in autoclave and at atmospheric pressure in glass reactor. At the beginning for each compound there were performed preliminary investigations. It was done by experimental investigations of the influence of each independent factor (parameter) on the course of the process at constant values remaining independent factors. The influence of the following technological parameters was investigated: temperature, the molar ratio allylic compound/hydrogen peroxide, methanol concentration (solvent), catalyst concentration and the reaction time. On the basis of these investigations the best technological parameters of epoxidation for each allylic compound not only at autogenic, but also at atmospheric pressure were established. These results were generalized and the general dependences for epoxidation of allylic compounds over titanium silicalite catalysts were presented. Than the correction of preliminary established ranges of process parameters for selected allylic compounds was made and next there were performed for them the optimizations with help of mathematical method of experimental planning (rotatable-uniform design). The established optimal parameters were close to the best parameters obtained in preliminary investigations, but the best parameters of the process usually allowed to carry out the process in milder conditions at the same or close values functions describing the process. The comparison between the methods at atmospheric pressure and autogenic pressure showed a lot of similarities in course of both processes - the similarity in values not only the best parameters but also the functions describing the process. Although the pressure method allowed to perform the process in broader range of temperature and pressure, the method at atmospheric pressure was chosen as the best. The method needs lower capital spending connected with performing of the process. At the end of this work there was proposed the simplified technological scheme of epoxides production, it took also into consideration the stage of products separation and regeneration of catalyst.

3

Properties and manufacturingof steel-C/epoxy fiber-metal laminates

Dymacek P., Klement J.

Research Bulletin / Warsaw University of Technology, Institute of Aeronautics and Applied Mechanics

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2001

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nr 11

47-52

EN

The processes of manufacturing and testing of basic mechanical and fatigue properties of Fiber Metal Laminates (FML) based on the steel-C/epoxide that have been performed at the Institute of Aerospace Engineering this year are described in the paper The concept of FML is briefly explained and potential applications and possible modifications to improve the properties of the laminate are discussed.

4

Adhezja elastomerów do włókien. Część 2. Zastosowanie promotorów adhezji z grupami epoksydowymi w celu zwiększenia przyczepności gumy do kordów

Marasek T., Ślusarski L., Zaborski M., Parasiewicz W.

Elastomery

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2000

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T. 4, nr 1

15-22

PL

Zbadano wpływ promotorów adhezji z grupami epitlenkowymi na przyczepność kordów poliestrowych i poliamidowych do typowej mieszanki gumowej stosowanej w technologii opon. Mieszankę zmodyfikowano epoksydowanym kauczukiem naturalnym lub żywicą epoksydową. Stosowano różne utwardzacze lub zespoły utwardzaczy (poliamid, zasada Mannicha, fosforyn trifenylowy, rezorcyna). W celu porównania kordy impregnowano również kąpielą RFL. Stwierdzono korzystny wpływ promotorów, szczególnie kauczuku naturalnego epoksydowanego, na adhezję kordów do gumy. Wzrost siły, przy której nastąpiło wyrwanie nitki kordowej z paska gumowego w przypadku kordu poliestrowego wynosił maksymalnie 68%, a po impregnacji tego kordu kąpielą RFL 112%. Jednak modyfikacja mieszanki gumowej jest zabiegiem znacznie prostszym niż impregnacja kordów kąpielą RFL.

EN

An effect of promoters with epoxy groups on adhesion of polyester and polyamide cords to the typical rubber mix applied in the tyre technology, has been studied. The mix was modified with epoxidized natural rubber or epoxy resin. Different hardeners (polyaminoamide, Mannich base, triphenylphosphite, resorcinol) were used. For purpose of comparison cords were also impregnated with RFL bath. A positive effect of the promoters, particularly of the epoxidized natural rubber on adhesion of cords to the vulcanizates. An increase of a pulling force in the 'H' test, in the case of polyester cord reached maximal 68%, after impregnation with RFL bath it was possible to obtain an increase of the pulling force ranging 112%. However a modification of a rubber mix is much simpler operation in comparison to the impregnation of cords with RFL bath.