WOOD THE POTENTIAL RESOURCE OF COMPLEX USE OF LIGNIN

The aim of the work is to investigate the use of existing wood waste, the most effective method of obtaining lignin and to create composite material made from renewable natural resources. The work looked at the current wider use of wood resources - construction, energy and chemical processing. The current waste from the use of wood - lignin is investigated. And the complex and rational use of this waste without waste. Experimentally, lignin was obtained with two methods, alkali and acid, from different Latvian tree species. Experimentally obtained composite samples with different compositions - alkali / acid lignin (binder) and leafy tree ash / chips (filler). Also, composite materials are considered at different proportions, where the percentage of both binders and fillers changes. Experimental samples were pressed at different temperatures.

Download Full-text

The Influence of Composite Polymeric Materials Topology Over the Shearing Modulus Using Virtual Instruments

Materiale Plastice ◽

10.37358/mp.18.4.5067 ◽

2018 ◽

Vol 55 (4) ◽

pp. 524-530

Author(s):

Marinela Marinescu ◽

Larisa Butu ◽

Claudia Borda ◽

Delicia Arsene ◽

Mihai Butu

Keyword(s):

Composite Material ◽

Composite Materials ◽

Virtual Instrument ◽

Mechanical Characteristics ◽

Polymeric Materials ◽

Mechanical Impedance ◽

Impedance Analysis ◽

Cross Linking ◽

Labview Software ◽

Different Temperatures

This study presents research regarding the calculation of the mechanical characteristics of composite polymeric materials. By using LabVIEW� software a virtual instrument was created used for monitoring in real time the process of cross-linking the composite polymeric materials. The experiments were realized based on composite materials containing epoxy/fiberglass resin of different topologies. By means of the virtual instrument and of a sensor created based on the mechanical impedance analysis, implanted in the composite material, it was determined the G shearing module of the composite material at different temperatures.

Download Full-text

Solution properties of polyaniline/carbon particle composites

Journal of Polymer Engineering ◽

10.1515/polyeng-2015-0091 ◽

2016 ◽

Vol 36 (3) ◽

pp. 299-307

Author(s):

Huseyin Zengin ◽

Erdal Bayir ◽

Gulay Zengin

Keyword(s):

Molecular Weight ◽

Composite Material ◽

Composite Materials ◽

In Situ Polymerization ◽

Carbon Particle ◽

Conductive Polymer ◽

Ionic Conductivities ◽

Solution Properties ◽

Different Temperatures

Abstract This study reports on the synthesis of polymer polyaniline, a conductive polymer by nature, and the preparation of polyaniline/carbon particle (PANI/CP) composites by in situ polymerization. The solution properties and conductivities in solution of synthesized PANI and PANI/CP materials were analyzed. The viscosity of PANI and PANI/CP composite materials in N-methylpyrrolidinone (NMP) solvent at different temperatures was measured to examine their behavior in solution. Initially, the viscosity-molecular weight of PANI polymer was measured and calculated to be 78,521. The viscosities of PANI and PANI/CP composite materials decreased as the temperature increased. However, the viscosities of PANI/CP composite materials increased as the percent CP content in the composites increased. The ionic conductivities and pH changes in NMP solvent, measured at different concentrations of PANI and PANI/CP composite materials, and prepared in different ratios, were measured to investigate their behavior in solution. The ionic conductivities of PANI/CP composite materials increased as the percent CP content in the composites increased. Changes in the pH of PANI/CP composite materials decreased as the percent CP content in the composites increased. The conductivity of PANI/10% CP composite material in solution was greater than that of neat PANI polymer in solution; this indicated that CPs in PANI/10% CP composite materials made important positive contributions to the conductivities.

Download Full-text

Hydrogen Storage Properties of Magnesium Based Nanostructured/Amorphous Composite Materials

MRS Proceedings ◽

10.1557/proc-801-bb1.5 ◽

2003 ◽

Vol 801 ◽

Cited By ~ 1

Author(s):

Ming Au

Keyword(s):

Composite Material ◽

Composite Materials ◽

Hydrogen Storage ◽

Mechanical Alloying ◽

Particle Morphology ◽

New Materials ◽

Nanostructured Composite ◽

Different Temperatures ◽

The Stability ◽

Kinetics Of

ABSTRACTIn this work, nanostructured composite materials Mg-Ni, Mg-Ni-La, Mg-Ni-Ce and Mg-LaNi5 have been synthesized using the mechanical alloying process. The new materials produced have been investigated by X-ray diffraction (XRD), TEM, SEM and EDS for their phase compositions, crystal structure, grain size, particle morphology and the distribution of the catalyst elements. Hydrogen storage capacities and the hydriding-dehydriding kinetics of the new materials have been measured at different temperatures using a Sieverts apparatus. The results show that amorphous/nanostructured composite material Mg50%-Ni50% absorbs 5.89wt% within five minutes and desorbs 4.46% hydrogen within 50 minutes at 250°C respectively. Adding 5% La into Mg-Ni composite materials reduces the starting temperature of hydrogen absorption and desorption from 200°C to 25°C which suggests the formation of unstable hydrides. The composite material Mg80%-LaNi5 20% absorbs 1.96% hydrogen and releases 1.75 wt% hydrogen at 25°C. It is observed that mechanical alloying accelerates the hydrogenation kinetics of the magnesium based materials at low temperature, but a high temperature must be provided to release the absorbed hydrogen from the hydrided magnesium based materials. It is believed the dehydriding temperature is largely controlled by the thermodynamic configuration of magnesium hydride. Doping Mg-Ni nano/amorphous composite materials with lanthanum reduces the hydriding and dehydriding temperature. Although the stability of MgH2 can not be easily reduced by ball milling alone, the results suggest the thermodynamic properties of Mg-Ni nano/amorphous composite materials can be alternated by additives such as La or other effective elements. Further investigation toward understanding the mechanism of additives will be rewarded.

Download Full-text

Low-temperature tension properties of glass-epoxy composite materials

Acta periodica technologica ◽

10.2298/apt0536123p ◽

2005 ◽

pp. 123-134

Author(s):

Slavisa Putic ◽

Marina Stamenovic ◽

Branislav Bajceta ◽

Predrag Stajcic ◽

Srdjan Bosnjak

Keyword(s):

Tensile Strength ◽

Composite Material ◽

Composite Materials ◽

Room Temperature ◽

Epoxy Composite ◽

Epoxy Composites ◽

Tension Properties ◽

Different Temperatures ◽

Stereo Microscope

The aim of this paper was to present the determination of tensile strength Rm and modulus of elasticity Et of glass-epoxy composites at two different temperatures (at room temperature t=20?C, and at t =?50?C). Standard mechanical testing was carried out on glass woven-epoxy composite material with different structures (two specific weights of reinforcement, 210 g/m2 and 550 g/m2) and orientations (0?/90? and ?45?). Micromechanical analysis of failure was performed on a stereo microscope and SEM in order to determine real models and mechanisms of crack.

Download Full-text

Ecological Enlightenment: System Approach

Bibliotekovedenie [Library and Information Science (Russia)] ◽

10.25281/0869-608x-2013-0-4-112-116 ◽

2013 ◽

pp. 112-116

Author(s):

Galina I. Kukatova

Keyword(s):

Environmental Education ◽

Natural Resources ◽

System Approach ◽

Ecological Knowledge ◽

Rational Use

The article is devoted to the problems of protection and rational use of natural resources of the Bryansk region, the environmental education of the population and propaganda of ecological knowledge and the activities of the regional libraries in this area.

Download Full-text

Study of the Composite Materials Optimal Structure Containing a Hollow Aluminum and Silica Microsphere Dependence on Humidity

Micro and Nanosystems ◽

10.2174/1876402912999201109204218 ◽

2020 ◽

Vol 12 ◽

Author(s):

Alexandra Atyaksheva ◽

Yermek Sarsikeyev ◽

Anastasia Atyaksheva ◽

Olga Galtseva ◽

Alexander Rogachev

Keyword(s):

Composite Material ◽

Composite Materials ◽

Strength Function ◽

Theory And Practice ◽

Optimal Structure ◽

Optimal Size ◽

Structure And Properties ◽

Power Functions ◽

Silica Microsphere ◽

Heat Engineering

Aims:: The main goals of this research are exploration of energy-efficient building materials when replacing natural materials with industrial waste and development of the theory and practice of obtaining light and ultra-light gravel materials based on mineral binders and waste dump ash and slag mixtures of hydraulic removal. Background.: Experimental data on the conditions of formation of gravel materials containing hollow aluminum and silica microsphere with opportunity of receipt of optimum structure and properties depending on humidity with the using of various binders are presented in this article. This article dwells on the scientific study of opportunity physical-mechanical properties of composite materials optimization are considered. Objective.: Composite material contains hollow aluminum and silica microsphere. Method.: The study is based on the application of the method of separation of power and heat engineering functions. The method is based on the use of the factor structure optimality, which takes into account the primary and secondary stress fields of the structural gravel material. This indicates the possibility of obtaining gravel material with the most uniform distribution of nano - and microparticles in the gravel material and the formation of stable matrices with minimization of stress concentrations. Experiments show that the thickness of the cement shell, which performs power functions, is directly related to the size of the raw granules. At the same time, the thickness of the cement crust, regardless of the type of binder, with increasing moisture content has a higher rate of formation for granules of larger diameter. Results.: The conditions for the formation of gravel composite materials containing a hollow aluminosilicate microsphere are studied. The optimal structure and properties of the gravel composite material were obtained. The dependence of the strength function on humidity and the type of binder has been investigated. The optimal size and shape of binary form of gravel material containing a hollow aluminosilicate microsphere with a minimum thickness of a cement shell and a maximum strength function was obtained. Conclusion.: Received structure allows to separate power and heat engineering functions in material and to minimize the content of the excited environment centers.

Download Full-text

Hierarchical ZSM-22/PHTS composite material and its hydro-isomerization performance in hydro-upgrading of gasoline

Catalysis Science & Technology ◽

10.1039/d1cy00400j ◽

2021 ◽

Author(s):

Jiyuan Fan ◽

Chengkun Xiao ◽

Jinlin Mei ◽

Cong Liu ◽

Aijun Duan ◽

...

Keyword(s):

Composite Material ◽

Composite Materials ◽

Impregnation Method ◽

Molar Ratios

CoMo series catalysts based on ZSM-22/PHTS (ZP) composite materials with different SiO2/Al2O3 molar ratios were prepared via the impregnation method. The properties of the ZP material and the corresponding catalysts...

Download Full-text

Acoustic Emission and K-S Metric Entropy as Methods for Determining Mechanical Properties of Composite Materials

Sensors ◽

10.3390/s21010145 ◽

2020 ◽

Vol 21 (1) ◽

pp. 145

Author(s):

Lesław Kyzioł ◽

Katarzyna Panasiuk ◽

Grzegorz Hajdukiewicz ◽

Krzysztof Dudzik

Keyword(s):

Mechanical Properties ◽

Acoustic Emission ◽

Composite Material ◽

Composite Materials ◽

Testing Machine ◽

Measurement Data ◽

Entropy Method ◽

Displacement Sensor ◽

Metric Entropy ◽

Plastic Phase

Due to the unique properties of polymer composites, these materials are used in many industries, including shipbuilding (hulls of boats, yachts, motorboats, cutters, ship and cooling doors, pontoons and floats, torpedo tubes and missiles, protective shields, antenna masts, radar shields, and antennas, etc.). Modern measurement methods and tools allow to determine the properties of the composite material, already during its design. The article presents the use of the method of acoustic emission and Kolmogorov-Sinai (K-S) metric entropy to determine the mechanical properties of composites. The tested materials were polyester-glass laminate without additives and with a 10% content of polyester-glass waste. The changes taking place in the composite material during loading were visualized using a piezoelectric sensor used in the acoustic emission method. Thanks to the analysis of the RMS parameter (root mean square of the acoustic emission signal), it is possible to determine the range of stresses at which significant changes occur in the material in terms of its use as a construction material. In the K-S entropy method, an important measuring tool is the extensometer, namely the displacement sensor built into it. The results obtained during the static tensile test with the use of an extensometer allow them to be used to calculate the K-S metric entropy. Many materials, including composite materials, do not have a yield point. In principle, there are no methods for determining the transition of a material from elastic to plastic phase. The authors showed that, with the use of a modern testing machine and very high-quality instrumentation to record measurement data using the Kolmogorov-Sinai (K-S) metric entropy method and the acoustic emission (AE) method, it is possible to determine the material transition from elastic to plastic phase. Determining the yield strength of composite materials is extremely important information when designing a structure.

Download Full-text

Development of Detailed FE Numerical Models for Assessing the Replacement of Metal with Composite Materials Applied to an Executive Aircraft Wing

Aerospace ◽

10.3390/aerospace8070178 ◽

2021 ◽

Vol 8 (7) ◽

pp. 178

Author(s):

Valerio Acanfora ◽

Roberto Petillo ◽

Salvatore Incognito ◽

Gerardo Mario Mirra ◽

Aniello Riccio

Keyword(s):

Composite Material ◽

Composite Materials ◽

Numerical Model ◽

Numerical Models ◽

Structural Performance ◽

Aircraft Wing ◽

Resin Infusion ◽

Effectiveness Analysis ◽

Liquid Resin Infusion ◽

Process Constraints

This work provides a feasibility and effectiveness analysis, through numerical investigation, of metal replacement of primary components with composite material for an executive aircraft wing. In particular, benefits and disadvantages of replacing metal, usually adopted to manufacture this structural component, with composite material are explored. To accomplish this task, a detailed FEM numerical model of the composite aircraft wing was deployed by taking into account process constraints related to Liquid Resin Infusion, which was selected as the preferred manufacturing technique to fabricate the wing. We obtained a geometric and material layup definition for the CFRP components of the wing, which demonstrated that the replacement of the metal elements with composite materials did not affect the structural performance and can guarantee a substantial advantage for the structure in terms of weight reduction when compared to the equivalent metallic configuration, even for existing executive wing configurations.

Download Full-text

Impact of Prolonged Exposure of Eleven Years to Hot Seawater on the Degradation of a Thermoset Composite

Polymers ◽

10.3390/polym13132154 ◽

2021 ◽

Vol 13 (13) ◽

pp. 2154

Author(s):

Amir Hussain Idrisi ◽

Abdel-Hamid I. Mourad ◽

Muhammad M. Sherif

Keyword(s):

Exposure Time ◽

Prolonged Exposure ◽

Mechanical Performance ◽

Matrix Cracking ◽

Pull Out ◽

Strength Based ◽

Different Temperatures ◽

River Line ◽

Composite Samples

This paper presents a long-term experimental investigation of E-glass/epoxy composites’ durability exposed to seawater at different temperatures. The thermoset composite samples were exposed to 23 °C, 45 °C and 65 °C seawater for a prolonged exposure time of 11 years. The mechanical performance as a function of exposure time was evaluated and a strength-based technique was used to assess the durability of the composites. The experimental results revealed that the tensile strength of E-glass/epoxy composite was reduced by 8.2%, 29.7%, and 54.4% after immersion in seawater for 11 years at 23 °C, 45 °C, and 65 °C, respectively. The prolonged immersion in seawater resulted in the plasticization and swelling in the composite. This accelerated the rate of debonding between the fibers and matrix. The failure analysis was conducted to investigate the failure mode of the samples. SEM micrographs illustrated a correlation between the fiber/matrix debonding, potholing, fiber pull-out, river line marks and matrix cracking with deterioration in the tensile characteristics of the thermoset composite.

Download Full-text