Wyniki wyszukiwania - Biblioteka Nauki

1

Wybrane właściwości mieszanin niskotopliwych stopów metalicznych z polimerami termoplastycznymi.

100%

Włodarczyk E. , Gubański A. , Steller R.

Prace Naukowe Instytutu Podstaw Elektrotechniki i Elektrotechnologii Politechniki Wrocławskiej. Konferencje

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2006

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tom Vol. 44, nr 18

106-110

PL

Przeprowadzono badania wpływu składu na strukturę i właściwości kompozycji poliamidu 6 oraz polipropylenu, zawierających dodatek niskotopliwych stopów metali o temperaturze topnienia w zakresie 70-195 st C. Odpowiednie kompozycje sporządzono posługując się wtryskarką "Arburg 250-255 oraz mieszalnikiem typu "Brabender". Preparatyka pozyskiwanych próbek opierała się na metodach wtryskiwania i prasowania. Przeprowadzono badania właściwości elektrycznych tj.: spektroskopia dielektryczna, badania charakterystyk I-V. Ponadto zbadano właściwości cieplne oraz mechaniczne pozyskanych mieszanin. W wyniku badań stwierdzono, że dodatek niskotopliwych stopów metali w znaczący sposób zmienia charakterystykę elektryczną, cieplną i mechaniczną kompozycji.

EN

Effect of composition structure and some properties of blends based on polyamide and polypropylene matrix with low melting metal alloys was investigated. Compositions were prepared with injection moulding machine and "Brabender" type mixer. Test specimens were forming by injection moulding machine and hydraulic press. Electrical, thermal and mechanical properties of compositions were studied. It was found that blends based on polyamide and polypropylene matrix with low melting metal alloys as a fillers change significantly mechanical and thermal characteristic of compositions. Also electrical properties were changed but that effect demand further and widely studies.

2

Evaluation of the Interaction Among Microalgae Spirulina sp, Plastics Polyethylene Terephthalate and Polypropylene in Freshwater Environment

100%

Khoironi A. , Anggoro S. , Sudarno

Journal of Ecological Engineering

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2019

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tom Vol. 20, nr 6

161--173

EN

The annual plastic production in Indonesia has exceeded 4.6 million tons and accumulated in the aquatic system. Polyethylene terephthalate (PET) and Polypropylene (PP) are the most widely used plastics in manufacture of packaging, fibres, and drinking bottles, etc. The degradation of these plastics to micro sizes leads to environmental threats, especially when the micro plastics interact with fresh water microorganism such as microalgae. Therefore, the study on the interaction between micro plastics and microorganisms is really important. The aim of this study was to evaluate the impact of microplastics on the growth of microalgae Spirulina sp and also to evaluate the contribution of microalgae Spirulina sp to the plastic degradation. The interaction between microalgae and microplastics was evaluated in a 1 L glass bioreactor contained microalgae Spirulina sp and PP and PET microplastics with the size of 1 mm at various concentrations (150 mg/500 mL, 250/500 mL and 275 mg/500 mL) for 112 days. The results showed that the tensile strength of micro plastic PET decreased by 0.9939 MPa/day while PP decreased by 0.1977 MPa/day. The EDX analysis of microplastics showed that the decreasing carbon in PET (48.61%) was higher as compared to PP (36.7%). FTIR analysis of Spirulina sp cells showed that the CO2 evolution of cells imposed by PET microplastic was higher than imposed by PP. The growth rate of Spirulina sp applied by micro plastic was lower than the control and the increase of microplastic concentration significantly reduced the growth rate of algae by 75%. This research concluded that biodegradation has important role in the degradation process of plastic.

3

Chitosan immobilization to the polypropylene nonwoven after activation in atmospheric – pressure nitrogen plasma

100%

Černáková Ľ. , Černák M. , Tóth A. , Mikulášová M. , Tomašková M. , Kováčik D.

Open Chemistry

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2015

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tom 13

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nr 1

EN

Atmospheric-pressure air and nitrogen plasmas generated by surface dielectric barrier discharges have been used to incorporate new functionalities at the surface of polypropylene nonwoven fabric. The main goals were to activate the polymer surfaces for subsequent immobilization of chitosan from water solution without using any crosslinking and wetting agents. The samples were analyzed by diffuse reflectance infrared Fourier transform spectroscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. The nitrogen plasma treatment resulted in relatively high oxygen incorporation, about 9 atomic % mainly in aliphatic C=O type bonds and about 4 at.% of nitrogen incorporation in amine and other nitrogen functionalities. Chitosan was immobilized on the fabric fibers surfaces very homogeneously in amount of 2 - 5 g m-2. The chitosan coated samples exhibited a good laundering durability and strong antimicrobial activity against Bacillus subtilis and Escherichia coli.

4

Walnut shells as a filler for polymeric materials

100%

Dobrzyńska-Mizera M. , Knitter M. , Barczewski M.

Drewno : prace naukowe, doniesienia, komunikaty

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2019

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tom vol. 62, nr 203

153--168

EN

This work presents selected properties of polypropylene-based (PP) composites modified with an organic filler, namely walnut shells (NUT). Two series of composites were prepared via a twin-screw extrusion process, followed by injection molding. The first series, named PP/NUT, contained 10, 20 and 40 wt% of walnut shell powder, while the second, abbreviated PP/NUT/MAPP, apart from nut filler included polypropylene-graft-maleic anhydride (MAPP), which was intended to promote adhesion between the polymer and filler. The following measuring techniques were applied: differential scanning calorimetry, thermogravimetry, dynamic-mechanical thermal analysis, and scanning electron microscopy. The measurements showed the filler to have a significant influence on the properties of the PP/NUT composites in comparison with unmodified polypropylene. It was also shown that the addition of polypropylene-graft-maleic anhydride to the formulation enhanced interfacial bonding between the polymeric matrix and filler. Moreover, the introduction of organic filler to the polymeric matrix increased its stiffness without altering the crystallization kinetics of polypropylene.

5

Ocena właściwości polipropylenu (PP) pochodzącego z obudów akumulatorów ołowiowych

100%

Czarnecka-Komorowska D. , Janicki M.

Przetwórstwo Tworzyw

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2011

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tom [R.] 17, nr 5

299-301

PL

W artykule przedstawiono wyniki badań oceny właściwości mechanicznych i przetwórczych polipropylenu (PP) otrzymanego w wyniku recyklingu materiałowego obudów akumulatorowych. Analizie poddano cechy mechaniczne (statyczne rozciąganie, udarność, twardość) oraz cieplne (DSC, Vicat) i reologiczne dla polimeru pierwotnego i wtórnego (przemiału i regranulatu). Uzyskane wyniki wskazują, że materiały oparte na regranulatach (rPP) mogą być wykorzystywane do produkcji dobrej jakości wyrobów z tworzyw sztucznych w wielu zastosowaniach technicznych.

EN

This research work is concerned with the evaluation of the mechanical properties and thermal changes of polypropylene (PP) from used car battery case. The experiments included tensile tests, impact tests, thermal (DSC, Vicat), hardness and rheology testing. The results obtained show that resins based on regraunlates (rPP) can be used to produce good quality plastics in many, engineering applications.

6

Thermal stability of different nucleating additives used for poly(propylene)

100%

Frick A. , Lenża J.

Zeszyty Naukowe. Chemia / Politechnika Śląska

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2001

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tom z. 146

203-206

PL

W pracy tej przeprowadzono badanie stabilności i degradacji termicznej polipropylenu oraz zawartych w nim zarodków krystalizacji. Różnicową Kalorymetrię Skaningową wykorzystano do symulacji warunków realnego procesu. Wyniki świadczą, że metoda DSC pozwala szybko ocenić jakość badanego tworzywa polimerowego.

7

Plastics in new and end-of-life electrical and electronic equipment

100%

Machnicka-Hławiczka M. , Walczak K. , Rejman-Burzyńska A.

Prace Naukowe Instytutu Inżynierii Ochrony Środowiska Politechniki Wrocławskiej. Konferencje

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2006

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tom Vol. 81, nr 12

149-154

EN

Nowadays electrical and electronic (E&E) sector is highly innovative one and this is in part due to the fact that it is based on use of plastics. Thanks to their multipurpose characteristics which are perfectly suited to today's techniques, plastics are an ideal resource to produce highly functioning electronic products and are available to satisfy the wide range of quality requirements of the different applications. Plastics in E&E equipment can help save resources because they facilitate the ongoing reduction of energy consumption during the use phase. Important is also the fact that the price performance ratio of electrical and electronic equipment is getting better every day. As a result, a large quantity of plastics is used in E&E equipment manufacture and today it is about 8% of entire (total) plastics production.

PL

Omówiono rodzaje i właściwości tworzyw sztucznych stosowanych w urządzeniach elektrycznych i elektronicznych, zwrócono uwagę na dodatki opóźniające palenie i inne dodatki. zwłaszcza zawierające metale ciężkie. Przedyskutowano operacje związane z zagospodarowaniem odpadów WEEE. ze szczególnym uwzględnieniem demontażu oraz mielenia.

8

Recycling of polypropylene/wood flour composites

100%

Viksne A. , Rence L. , Rucina M.

Prace Naukowe Instytutu Inżynierii Ochrony Środowiska Politechniki Wrocławskiej. Konferencje

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2006

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tom Vol. 81, nr 12

31-35

EN

The use of the lignocellulosic materials as reinforcing fillers for polymeric matrices has increased importantly in last decades. Resulting composites are processed into various products (automobile parts, window frames, various construction materials etc.), which will have to be recycled after end of their useful life. The goal of this study was to investigate the behaviour of the wood flour/PP composites (WPC) during repeated processing cycles. How many mixing cycles will be possible without significant change of the mechanical properties of resulting material.

PL

Wykazano możliwość recyklingu kompozytów PP z mączką drzewną bez istotnego pogorszenia wytrzymałości mechanicznej. Po 2-3 cyklach zwiększa się nieco wytrzymałość na rozciąganie i udarność, natomiast po czwartym cyklu zmniejsza się chłonność wody. Zmiany przypisano lepszej dyspersji włókien w osnowie polimerowej oraz zwiększonej adhezji międzyfazowej będącej następstwem degradacji polipropylenu.

9

Examination of shredding process parameters and the properties of recyclate

100%

Głogowska K. , Rozpędowski J.

Advances in Science and Technology. Research Journal

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2016

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tom Vol. 10, nr 29

176--179

EN

Shredding is the component of the most important techniques of mechanical recycling of polymeric materials. It is often used as one of the main preparatory processes, associated with the constitution of composite materials. This means that it is a very important and current problem to be solved in terms of technology, design, and economy, as well as environmental protection. A preparation of composite material components by shredding depends specfically on the expected degree of fineness, appropriate size distribution and desired morphology of an elementary particle. The subject of this work concerns mechanical shredding of polymeric materials in various types of mills and agglomerators. The paper presents the tests for verifying the influence of size and shapes of openings in sieves made in the shredder on selected parameters and properties of the obtained recyclate. During the shredding process, the following parameters were analysed: electricity consumption, temperature inside the shredding chamber and the temperature of the obtained recyclate. Selected properties of the obtained recyclate, such as: geometric features of the recyclate dependent on the applied sieves, bulk density and the angle of natural repose were also determined. Mouldings with a gating system, made of polypropylene, were the subject of shredding.

10

Optimization of laser cutting conditions of polypropylene and polypropylene with talc

100%

Cienka A. E. , Ciecińska B.

Physics for Economy

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2021

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tom Vol. 4

5-15

EN

Laser cutting of materials requires the execution of processing tests and the selection of the most favourable variant from the point of view of the adopted criteria of process quality assessment. This paper presents the example of a preparatory process, which shows that cutting polypropylene and polypropylene with 5 mm thick talc is not an easy process of material handling. A CO2 laser was used and by varying the utilized power from the laser and the beam speed relative to the material, cuts of varying quality were obtained. Criteria were also proposed for the selection of the best processing variant. It was concluded that the addition of talc to polypropylene can be a factor facilitating laser cutting of this material.

11

The influence of the deposition time on morphological and optical properties of Cu x S films deposited on polypropylene substrate

100%

Pop A. E. , Popescu V. , Dinescu A. , Batin M. N.

Materials Science Poland

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2013

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tom Vol. 31, No. 3

318--324

EN

Copper sulfide (CuxS) films deposited on polypropylene substrate were obtained by chemical bath deposition (CBD) method. The influence of the deposition time on the morphology of CuxS films was studied by means of scanning electron microscopy. We have found that the average particles dimension increased from 37 to 49 nm with the increase of deposition time from 20 to 30 minutes. The study of optical properties of the copper sulfide films was carried out based on optical transmission spectra recorded in the 400 – 1000 nm wavelength range. The optical constants, such as refractive index, extinction coefficient and dielectric constant as well as electrical and optical conductivity of CuxS films were calculated. The obtained values are in accordance with the ones reported in the literature: We have shown that both, morphological and optical properties of CuxS films are strongly affected by the deposition time.

12

Wpływ naświetlania promieniowaniem UV i działania plazmy H2O2 na właściwości polisulfonu i polipropylenu

100%

Kowal J. , Czajkowska B. , Bulwan E.

Inżynieria Biomateriałów

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2004

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tom R. 7, nr 38-42

154-157

13

Effects of coupling agent on antioxidant properties and structure of PP/ cotton stalk lignin composites

100%

He M. , Musajian D. , Hasan G. , Hou, G. , Yimit M.

Polish Journal of Chemical Technology

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2020

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tom Vol. 22, nr 2

78--85

EN

In this paper, the effects of coupling agent and lignin extracted from waste cotton stalks in Xinjiang on thermaloxygen aging properties of polypropylene (PP) composites were studied. The melt index test and indoor thermal oxygen aging test was carried out on the samples treated with coupling agent. The mechanical properties, surface micromorphology, rheological properties and element composition of the materials before and after 30 days of aging were studied. The results showed that the titanate coupling agent was the best for improving the melt index and mechanical properties of PP/cotton stalk lignin composites. After the 30-day thermal oxygen aging test, the samples with 2% lignin had the best impact strength and retention rate of fracture elongation, reaching 68.9% and 77.3% respectively. The sample with 3% lignin content had the smoothen surface, no crack appeared. After aging, the increase of C=O was the least, and the crystal peak area decreased less.

14

Compatibilisation of PP/PA Blends

89%

Kristofic M. , Ujhelyiova A.

Fibres & Textiles in Eastern Europe

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2012

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tom Vol. 20, no. 4 (93)

30--36

EN

Blending polymers is widely used for the preparation of new materials. The disadvantage of this application is that the polymer components are usually not compatible and the preparation of blends with suitable (mainly processing and mechanical) properties is not satisfactory. The use of a third compound, called a compatibiliser, is an effective way to ameliorate the end-use properties of the blend. Compatibilisers based on grafted or block copolymers are often used. The present contribution deals with the compatibilisation of polypropylene/polyamide blends with compatibilisers based on grafted or block polyolefines.

PL

W przypadku kiedy polimery mające ulec zmieszaniu nie są kompatybilne stosuje się środki pomocnicze zwane kompatybilizatorami. Często stosuje się kompatybilizatory oparte na polimerach blokowych lub szczepionych. W artykule omówiono mieszanie polipropylenu z poliamidem z zastosowaniem szczepionych lub blokowych poliolefin.

15

Chemiczna modyfikacja polipropylenu przy użyciu żywic oligomerycznych

88%

Legocka I. , Bujnowska E. , Łukaszewska E. , Gałęski A. , Bartczak Z.

Prace Naukowe Instytutu Technologii Organicznej i Tworzyw Sztucznych Politechniki Wrocławskiej. Konferencje

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2001

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tom Vol. 50, nr 23

548-551

PL

Przedmiotem badań była modyfikacja izotaktycznego polipropylenu w celu zwiększenia jego wytrzymałości mechanicznej, szczególnie naprężenia na granicy plastyczności [delta]y oraz zwiększenia barierowości dla gazów. Chemiczną modyfikację PP prowadzono związkami oligomerycznymi o dobranym ciężarze cząsteczkowym i budowie chemicznej. Wprowadzone modyfikatory związane z łańcuchem PP częściowo rozpuszczone będą w fazie amorficznej i częściowo uwięzione w krystalitach polimeru.

EN

The modification of polypropylene with some oligomeric resins was been studied. The raw materials were activated by radiation method, using electron beam. The structural, thermal and mechanical propertiies of the obtained compositions were been measured.

16

Modyfikacja palności i właściwości antystatycznych polipropylenu

88%

Poźniak R. , Pasternak A. , Mróz J.

Prace Naukowe Instytutu Technologii Organicznej i Tworzyw Sztucznych Politechniki Wrocławskiej. Konferencje

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2001

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tom Vol. 50, nr 23

543-547

PL

Przedstawiono wyniki badań nad zmniejszeniem palności ortaz ograniczeniem elektryzacji statycznej polipropylenu. Zmniejszenie palności PP uzyskano przez dodatek bromowych antypirenów: FR 1206, FR 1025 oraz reoflam Fg-372. Stwierdzono że ich efektywność zależy od budowy chemicznej oraz od obecności tritlenku antymonu. Maksymalny efekt synergizmu uwidaczniał się przy stosunku wagowym antypirenu do Sb2O3 jak 2:1 i 3:1. Zastosowano zewnętrzną antystatyzację PP z dodatkami uniepalniającymi oraz nanoszenie antystatyków z roztworów wodnych, co pozwoliło zredukować elektryzacje polipropylenu do wartości uznanych za bezpieczne w warunkach zagrożenia pożarowego i wybuchowego.

EN

The flammability and antistatic properties of polypropylene composites have been investigated. Three types of the bromine compounds were used as flame retardants: FR 1206, FR 1025, and Reoflam FG-372. The synergist antimony oxide has been used to impart flame retardancy of polypropylene. Hexabromocyclodecane (FR 1206) as a flame retardans, PS-8 and PS-13 (quaternary ammonium methasulphate) as an external antistatic agents gave the best results.

17

Tensile mechanical properties in PP/SEBS/Microballon composites under impact loadings

88%

Mae H.

Journal of Achievements in Materials and Manufacturing Engineering

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2008

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tom Vol. 31, nr 2

341-347

EN

Purpose: The mechanical properties of the syntactic polymer foams at the intermediate and high strain rates were not understood comprehensively. Then, this study characterizes the tensile mechanical properties of the polymer syntactic composites at high strain rates. Design/methodology/approach: Eight kinds of syntactic foams and one neat PP/SEBS specimens are prepared at the same manufacturing process: 0, 2, 4, 8, 10, 20, 30, 40 and 50 volume percents of microballoons in the PP/SEBS blend matrix. Tensile tests are conducted at strain rates ranged from 0.3 to 100 s-1. Apparent elastic modulus, yield stress and rupture strain are measured and the effects of microballoons on the mechanical properties are studied. In addition, the experimental results are compared with analytical model for closed-cell foam and the effects of the density of the PP/SEBS/microballoon composite on both apparent elastic modulus and yield stress are discussed. Findings: The apparent elastic moduli of PP/SEBS/microballoon syntactic composites follow the Gibson-Ashby law at the nominal strain rate of 100 s-1. The yield stress of PP/SEBS/microballoon syntactic composites follow the simple rule of mixture at the relative densities larger than 0.9. The material ductility decreases drastically once the microballoons are blended in the matrix material. Research limitations/implications: The influence of the local strain rate caused by the heterogeneous microstructure on the mechanical properties is to be further explored. Practical implications: In the automobile applications, the thermoplastic polymer syntactic foams are believed to have many advantages because the usual commercial extruders or injection moulding machines are applicable for producing them, leading to the more light-weight polymeric components. Originality/value: The present study investigates the effects of the strain rate and density on the tensile mechanical properties comprehensively in the polymer syntactic foams.

18

Radiation effects in polypropylene/polystyrene blends as the model of aromatic protection effects

88%

Głuszewski W. , Zagórski Z. P.

Nukleonika

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2008

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tom Vol. 53, suppl. 1

21-24

EN

A technically useful composition containing polypropylene (PP) as a principal constituent, expected to be working or to be processed in ionizing radiation field, e.g. for sterilization, has to be protected from undesired radiolysis resulting in radiation damage. Usually, conventional additives are used which are generally effective, especially when containing aromatic groups. They can be sometimes unacceptable, e.g. in medical applications. Polystyrene (PS) has been investigated as a protective component, in analogy to the classical case of cyclohexane/benzene system. Mechanical mixing of both polymers showed to be of modest effect, but two other procedures, of soaking polypropylene powder with polystyrene dissolved in styrene, or soaking with styrene and gamma preirradiation with resulting grafting (G = 12000 effects/100 eV), resulted in the composition of improved resistance towards radiation. The energy transfer, which explains the effect, is extended at a distance of 8-12 mers of polypropylene. The investigations have been made by gas chromatography and diffuse light reflection spectrophotometry (DRS), after 10 MeV electron beam irradiations.

19

Effect of Composition on Melt Flow and Density of Polypropylene Copolymer/Kaolin Geo-Filler Composites

88%

Zulkifli Z. , Daud Y. M. , Zainal F. F. , Hashim M. F. A. , Aygörmez Y.

Archives of Metallurgy and Materials

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2023

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tom Vol. 68, iss. 1

369--373

EN

This study examined the effects rheological properties of different composition kaolin and kaolin geo-filler in polypropylene composites. Polypropylene composites with varying composition of kaolin geo-filler 0 wt%, 2 wt%, 4 wt%, 6 wt%, 8 wt%, and 10 wt% was prepared and compared with polypropylene composite with raw kaolin. Kaolin is an aluminosilicate based mineral filler was used to prepare geopolymer paste by combining with alkaline activator solution. The polypropylene composite was compounded using a twin-screw extruder and the melt flow index was determined by a constant weight pressure of 2.16 kg at 230°C in 10 min. Knowing the melt flow index is necessary to predict and control the process, the study has demonstrated that the composition of kaolin filler and kaolin geo-filler affects the melt flow, melt density and surface morphology at varies composition. Composites with kaolin geo-filler have demonstrated high melt flow index process and having better distribution and flow.

20

Technology of Utilization of Polypropylene Waste and Wastewater Sediments by Production of Building Blocks

88%

Levytska O. , Trus I. , Gomelya M. , Alekseyenko S.

Ecological Engineering & Environmental Technology

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2022

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tom Vol. 23, iss. 2

50--59

EN

Plastic waste and wastewater sediment stored on sludge lagoons are generated in almost every city in Ukraine. Their disposal is an urgent issue nowadays. The paper shows the ways of polypropylene utilization as one of the most widely used thermoplastics in everyday life, as well as the problem of formation and storage of wastewater sediments. The proposed technological scheme of complex processing of the resulted waste by production of building blocks is based on the property of polypropylene as a thermoplastic to soften and melt at above 160 °C, while exhibiting adhesive properties to a number of materials. For the implementation of technological solutions for manufacturing of construction products, the adhesion properties of polypropylene to wastewater sediments were substantiated, heating modes of the raw material mixture of wastewater sediments and polypropylene waste were specified, and the ratio of raw materials in the mixture for thermal treatment was determined. The samples of building blocks with a mass content of wastewater sediment from 5 to 95% (dry weight sediments) were made in the laboratory. In these samples, the polypropylene content was reduced from 95 to 5%, respectively. It was experimentally determined that for the samples of construction materials with a mass content of wastewater sediment 40–50% (dry weight), a uniform distribution of raw materials that would ensure their high strength, was observed. The comparison of the qualitative characteristics of the samples of building blocks with the regulatory requirements for construction products revealed that the experimental samples met the current requirements and were not inferior to the counterparts from traditional raw materials. However, the construction materials made from waste are recommended for application in building of industrial warehouses and storage facilities, non-food storage chambers, garages or other structures that do not provide permanent storage of food or living place for humans or animals.