Innovative technologies in corrosion-resistant coatings development aimed at ship navigation equipment protection

Author(s):  
Oleh Bezbakh

The efficient use of some innovative technologies in adhesives with advanced operational characteristics development aimed at anti-corrosion properties increase of transport means has been substantiated in the paper under discussion. The above-mentioned technologies involving the use of some interaction-active ingredients forming the cross-linkable coatings composition, including some polymers, have provided their cohesion properties essential improvement. Epoxy diane oligomer ED-16 has been chosen as the main component for the matrix in the composite formation. The aliphatic resin DЕG-1 (GOST 10136-77) as a plasticizer has been added to the epoxy oligomer. The compound has been formed of the following concentration: epoxy resin ED-16: plasticizer DЕG -1 – 100: 40. The hardener of cold hardening polyethelenepolyamine PEPA (ТУ 6-05-241-202-78) has been used at the epoxy resin-based developed materials polymerization. Phthalic acid anhydride has been used as a modifier to improve the properties of epoxy composite materials. The modifier was added to the matrix in the following ratio: from 0,10 to 2,00 pts.wt. per 100 pts.wt. of epoxy oligomer ЕD-20. The molecular formula of the modifier is as follows: C8H4O3. Molar mass is 148,1 g/mol. Density is ρ = 1,52 г/см³. To form a composite material or a protective coating with some improved adhesive properties and inconsiderable residual stresses the phthalic acid anhydride as a modifier was found to be added to the epoxy matrix with the content q = 1,25 pts.wt. per 100 pts.wt. of the epoxy matrix (oligomer ЕD-20 + plasticizer DЕG -1). In this case, the adhesive strength of the coating is being increased from sа = 28,3 MPа to sа = 46,4 MPа, and residual stresses – from sз = 1,9 MPа to sз = 2,1 MPа. First of all, the improved properties of the modified materials were caused by the interaction of active carbonyl (С=О) groups of the modifier with nitrogen-containing (NH-) groups of the hardener. It has provided the increase of the composite cross-linking degree resulted in their both adhesive and cohesion properties improvement. Moreover, it was found that the modifier use in the compound with the content q = 1,0…1,5 00 pts.wt. per 100 00 pts.wt. of the matrix has provided the increase of the river water influenced coatings resistance from ρ = 12,1 Оm·cm2 до ρ = 21,2…22,4 Оm·cm2. Though, some further increase of the additive content in the coating has caused the deterioration of anti-corrosion characteristics of the materials. Thus, the conducted study has contributed to the determination of the most efficient content ratio of phthalic acid anhydride as a modifier to for the coatings of functional use.

Author(s):  
Danyl Zhytnyk

The use of a new method of operational life increase of the transport means parts due to the introduction of polymer-based modified materials has been substantiated in the paper under discussion. It is shown that the use of matrices based on epoxy diane oligomers is quite promising direction in protective coatings formation. Some active additives have been applied to improve the properties of epoxy matrices on preliminary stage of their formation. The use of maleinic anhydride modifier containing active to the interphase interaction functional groups is promising as well. Epoxy diane oligomer has been used as the main component for the matrix in the composite formation. The hardener polyethelenepolyamine has been used to link the epoxy compositions enabling to harden the materials at room temperature. The choice of maleinic anhydride as a modifier to improve thermal-physical properties of the developed materials has been substantiated. It has been found that to form a composite material or a protective coating with improved thermal-physical properties it is necessary to apply maleinic anhydride as a modifier in epoxy matrix in the following ratio: q = 0,5 pts.wt. per q = 100 pts.wt. of epoxy oligomer ЕД-20. In this case the material has been formed where, comparing with nonmodified matrix, the indices of glass transition temperature are being increased from Тс = 327 К tо Тс = 335 К, heat resistance (by Martenson) from Т = 341 К to Т = 362 К, and thermal coefficient of linear expansion in the range of temperatures ∆Т = 303…423 К is being decreased from α = 9,9 ×10-5 К-1 to α = 4,4 ×10-5 К-1. It has been proved that the maleinic anhydride content in the matrix with its small fraction (q = 0,5 pts.wt.) has activated the processes of interphase interaction in epoxy CM structure formation, resulted in the increase of number of both physical and chemical bonds per polymer volume unit. This process will involve the increase of gel fraction degree in CM, and, correspondingly, both the cohesion and thermal-physical properties of modified CM have been improved. The developed material under discussion could be efficiently used as a matrix in formation of protective coatings which are to be operated under high temperatures conditions and dynamic or static loadings.


2020 ◽  
Vol 1 (22) ◽  
pp. 163-174
Author(s):  
А. V. Buketov ◽  
Т. V. Chernyavska ◽  
T. I. Ivchenko ◽  
K. M. Klevtsov ◽  
I. P. Fesenko ◽  
...  

The significance of application of the polymer composite materials in current technologies has been proven, since they have been demonstrating high performance parameters, offering improved adhesion failure resistance, enhanced mechanical and thermophysical properties which as a consequence enables their application under both ambient and elevated temperatures. The purpose of the current work is to investigate the influence of the phthalimide modifier on the adhesive and physico-mechanical properties of epoxy composite materials and protective coatings based on them. The ED-20 epoxy diane oligomer has been taken as the main component for the binder in the formation of epoxy materials. Polyethylene polyamine hardener has been used for the crosslinking of epoxy compositions. Phthalimide has been taken as a modifier. The molecular formula of the modifier is: C8H5NO2. The molar mass of phthalimide is 147.13 g/mol. It has been proven that with the introduction of the phthalimide modifier in the amount of 2.0 pts.wt. into 100 pts.wt. of ED-20 epoxy oligomer, the material which offers the following properties is being built up: adhesive failure resistance at breaking off - 47.7 MPa, residual stresses - 1.1 MPa. Compared to the parent epoxy matrix, these properties demonstrate an improvement of the adhesive failure resistance at breaking off by 1.9 times, and in addition to the above, the residual stresses are being reduced by 1.3 times. The composite obtained may be reasonably taken in the form of a matrix when building up an adhesive layer for protective coatings. It has been experimentally proven that in order to build up the materials which would offer improved cohesive properties, it is necessary to use a composition of the following makeup: ED-20 epoxy oligomer (100 pts.wt.), polyethylene polyamine hardener (10 pts.wt.), phthalimide modifier (0.25 pts.wt.). Compared to the parent epoxy matrix, the formation of that kind of a material provides an improvement of the following indicators of physical and mechanical properties of composites: bending critical stresses - from 48.0 MPa to 62.1 MPa; impact value - from 7.4 kJ/m2 to 14.7 kJ/m2. Note that the elasticity coefficient of this material is being reduced compared to the parent epoxy matrix from 2.8 GPa to 2.2 GPa. The composite obtained may be reasonably taken in the form of a matrix when building up the surface layer for protective coatings.


2013 ◽  
Vol 20 (3) ◽  
pp. 203-208 ◽  
Author(s):  
Leandro J. Silva ◽  
Juan C. Campos Rubio ◽  
Túlio H. Panzera ◽  
Paulo H.R. Borges

AbstractThermoset polymers, especially epoxy resin, have been applied in several industrial applications in which high stiffness and adhesive strength are demanded. On the other hand, epoxy resin is rather brittle and has poor fracture toughness. For this reason, the addition of fibres/particles into thermoset polymer can be used to enhance strength and toughness for several structural applications. This work investigated the addition of silica microparticles and maleic anhydride (as a coupling agent between the phases) into epoxy resin, which will be used as the matrix phase of hybrid biocomposites. A full factorial design was conducted to evaluate the effect of silica microparticles and chemical additive into the epoxy matrix under compressive loadings. Apparent density was also evaluated. Experimental factors such as weight fraction of silica microparticles (0, 20, and 33.3 wt%) and weight fraction of maleic anhydride (0 and 2 wt%) were investigated. The statistical analysis revealed that the main factors ‘chemical additive’ and ‘silica addition’ significantly affected the compressive modulus of the composites.


2006 ◽  
Vol 312 ◽  
pp. 179-186
Author(s):  
Jang Kyo Kim ◽  
Naveed A. Siddiqui ◽  
Ricky S.C. Woo ◽  
Christopher K.Y. Leung ◽  
Arshad Munir

The fracture resistance and mechanical properties of carbon fiber reinforced composites (CFRPs) containing organoclay-filled epoxy resin are studied. The XRD analysis and TEM examination revealed well-dispersed organoclay in the epoxy matrix displaying a mixture of exfoliation and intercalation. There was a significant improvement in flexural modulus and a marginal reduction in flexural strength of epoxy matrix due to the incorporation of organoclay. The quasi-static fracture toughness of epoxy increased nearly 60% with the addition of 3wt% clay, but there was a 45% drop in impact fracture toughness with 1wt% clay. When CFRPs were fabricated with the clay-modified epoxy resin, both the flexural modulus and strength of the hybrid composites showed negligible changes due to a few wt% of organoclay in the matrix. The interlaminar crack growth stability and the corresponding mode I interlaminar fracture toughness of the hybrid composites with organoclay improved substantially compared to those with carbon fibres only. The hybrid composites typically presented rough matrix surface associated with pinning and crack tip bifurcation, whereas the composite made from neat epoxy showed a smooth river line structure which is characteristic of brittle epoxy. The correlation between the composite interlaminar fracture properties and the toughness of modified matrix is discussed.


Author(s):  
Georgel MIHU ◽  
Claudia Veronica UNGUREANU ◽  
Vasile BRIA ◽  
Marina BUNEA ◽  
Rodica CHIHAI PEȚU ◽  
...  

Epoxy resins have been presenting a lot of scientific and technical interests and organic modified epoxy resins have recently receiving a great deal of attention. For obtaining the composite materials with good mechanical proprieties, a large variety of organic modification agents were used. For this study gluten and gelatin had been used as modifying agents thinking that their dispersion inside the polymer could increase the polymer biocompatibility. Equal amounts of the proteins were milled together and the obtained compound was used to form 1 to 5% weight ratios organic agents modified epoxy materials. To highlight the effect of these proteins in epoxy matrix mechanical tests as three-point bending and compression were performed.


Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 411
Author(s):  
Izabela Miturska ◽  
Anna Rudawska ◽  
Miroslav Müller ◽  
Monika Hromasová

The proper process of preparing an adhesive composition has a significant impact on the degree of dispersion of the composition ingredients in the matrix, as well as on the degree of aeration of the resulting composition, which in turn directly affects the strength and functional properties of the obtained adhesive compositions. The paper presents the results of tensile strength tests and SEM microphotographs of the adhesive composition of Epidian 57 epoxy resin with Z-1 curing agent, which was modified using three fillers NanoBent ZR2 montmorillonite, CaCO3 calcium carbonate and CWZ-22 active carbon. For comparison purposes, samples made of unmodified composition were also tested. The compositions were prepared with the use of six mixing methods, with variable parameters such as type of mixer arm, deaeration and epoxy resin temperature. Then, three mixing speeds were applied: 460, 1170 and 2500 rpm. The analyses of the obtained results showed that the most effective tensile results were obtained in the case of mixing with the use of a dispersing disc mixer with preliminary heating of the epoxy resin to 50 °C and deaeration of the composition during mixing. The highest tensile strength of adhesive compositions was obtained at the highest mixing speed; however, the best repeatability of the results was observed at 1170 rpm mixing speed. Based on a comparison test of average values, it was observed that, in case of modified compositions, the values of average tensile strength obtained at mixing speeds at 1170 and 2500 rpm do not differ significantly with the assumed level of significance α = 0.05.


2020 ◽  
Vol 10 (3) ◽  
pp. 1159 ◽  
Author(s):  
Yingmei Xie ◽  
Hiroki Kurita ◽  
Ryugo Ishigami ◽  
Fumio Narita

Epoxy resins are a widely used common polymer due to their excellent mechanical properties. On the other hand, cellulose nanofiber (CNF) is one of the new generation of fibers, and recent test results show that CNF reinforced polymers have high mechanical properties. It has also been reported that an extremely low CNF addition increases the mechanical properties of the matrix resin. In this study, we prepared extremely-low CNF (~1 wt.%) reinforced epoxy resin matrix (epoxy-CNF) composites, and tried to understand the strengthening mechanism of the epoxy-CNF composite through the three-point flexural test, finite element analysis (FEA), and discussion based on organic chemistry. The flexural modulus and strength were significantly increased by the extremely low CNF addition (less than 0.2 wt.%), although the theories for short-fiber-reinforced composites cannot explain the strengthening mechanism of the epoxy-CNF composite. Hence, we propose the possibility that CNF behaves as an auxiliary agent to enhance the structure of the epoxy molecule, and not as a reinforcing fiber in the epoxy resin matrix.


2012 ◽  
Vol 510-511 ◽  
pp. 577-584 ◽  
Author(s):  
A. Quddos ◽  
Mohammad Bilal Khan ◽  
R.N. Khan ◽  
M.K.K. Ghauri

The impregnation of the fiber with a resin system, the polymeric matrix with the interface needs to be properly cured so that the dimensional stability of the matrix and the composite is ensured. A modified epoxy resin matrix was obtained with a reactive toughening agent and anhydride as a curing agent. The mechanical properties of the modified epoxy matrix and its fiber reinforced composites were investigated systematically. The polymeric matrix possessed many good properties, including high strength, high elongation at break, low viscosity, long pot life at room temperature, and good water resistance. The special attentions are given to the matrix due to its low out gassing, low water absorption and radiation resistance. In addition, the fiber-reinforced composites showed a high strength conversion ratio of the fiber and good fatigue resistance. The dynamic and static of the composite material were studied by thermo gravimetric analysis (TGA), Differential Scanning Calorimetry (DSC) and Scanning Electron Microscopy (SEM) with EDX. The influences of processing technique such as curing and proper mixing on the mechanical and interfacial properties were determined. The results demonstrated that the modified epoxy resin matrix is very suitable for applications in products fabricated with fiber-reinforced composites.


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