Corrosion Protection Performance of Organic Offshore Coating Systems at −60 °C Temperature Shock

2016 ◽  
Vol 138 (6) ◽  
Author(s):  
A. W. Momber ◽  
M. Irmer ◽  
N. Glück ◽  
P. Plagemann
Keyword(s):  
Corrosion Protection ◽  
Loss Modulus ◽  
Accelerated Aging ◽  
Mechanical Analysis ◽  
Organic Coating ◽  
Temperature Sensitive ◽  
Sensitive Coating ◽  
Protection Capability ◽  
High Storage ◽  
Very High

Six organic coating systems were investigated according to their corrosion protection performance under simulated Arctic offshore conditions. The investigations involved accelerated aging, coating adhesion measurements, and dynamic mechanical analysis (DMA). The test conditions were adapted to Arctic offshore conditions, which mainly covered temperature shocks between −20 and −60 °C, chloride exposure, dry–wet cycles, and ultraviolet (UV) radiation. Corrosion protection capability dropped for all coatings if temperature decreased from −20 °C to −60 °C. Two types of coatings could be classified according to their response to the corrosive load: temperature-sensitive coatings and insensitive coatings. Adhesive effects (interface between coating system and substrate) were found to be marginal only at low temperatures and did not affect the response of the coatings to the corrosive load. Cohesive effects (mechanical properties of free polymer films) could be identified in terms of a very high storage modulus and changes in the loss modulus for a temperature-sensitive coating at −60 °C.

Accuracy in locating glass transitions: aging and gamma sterilization of vulcanized thermoplastic elastomers

e-Polymers ◽  
2009 ◽  
Vol 9 (1) ◽  
Author(s):  
Witold Brostow ◽  
Sameer Deshpande ◽  
Dorota Pietkiewicz ◽  
Steven R. Wisner
Keyword(s):  
Loss Modulus ◽  
Accelerated Aging ◽  
Mechanical Analysis ◽  
Thermoplastic Elastomers ◽  
Rapid Decrease ◽  
Practical Reasons ◽  
Glass Transitions ◽  
Γ Irradiation ◽  
Tan Δ

AbstractWe have studied nine thermoplastic vulcanizate elastomers (TPVs) in four series: as made, after accelerated aging, after γ irradiation, after both irradiation and aging. The materials exhibit two glass transitions, one seen in crosslinked regions and the other in un-crosslinked amorphous regions. Three techniques of determination of glass transitions have been used and the results compared, all three based on dynamic mechanical analysis (DMA): as a peak in the loss modulus E’’; as a peak in tan δ; and as the midpoint of the rapid decrease in the storage modulus E’. We recommend the last method for both fundamental and practical reasons.

EIS study of the corrosion behavior of an organic coating applied on Algerian oil tanker

2020 ◽  
Vol 117 (6) ◽  
pp. 610
Author(s):  
Nadia Hammouda ◽  
Kamel Belmokre
Keyword(s):  
Corrosion Protection ◽  
Electrochemical Impedance ◽  
Paint Film ◽  
Organic Coating ◽  
Diffusion Resistance ◽  
Double Layer Capacitance ◽  
Carbon Steel Surface ◽  
Chloride Environment ◽  
Oil Tanker ◽  
Epoxy Paint

Organic coatings are widely employed in the corrosion protection of most metal surfaces, particularly steel. They provide a barrier against corrosive species present in the environment, due to their high resistance to oxygen, water and ions transport. This study focuses on the evaluation of corrosion protection performance of epoxy paint on the carbon steel surface in chloride environment (3% NaCl) by Electrochemical Impedance Spectroscopy (EIS). The electrochemical behavior of painted surface was estimated by EIS parameters that contained paint film resistance, paint film capacitance and double layer capacitance. On the basis of calculation using EIS spectrums it was observed that pore resistance (Rpore) decreased with the appearance of doubled layer capacitance (Cdl) due to the electrolyte penetration through the film. This was further confirmed by the decrease of diffusion resistance (Rd) which was also the indicator of the deterioration of paint film protectiveness. Microscopic analyses have shown that oxidation dominates the corroded surfaces.

Development of low temperature curing, 120°C, durable, corrosion protection powder coatings for temperature sensitive substrates

2005 ◽  
Vol 2 (8) ◽  
pp. 661-668 ◽  
Author(s):  
Glen Merfeld ◽  
Steve Mordhorst ◽  
Rainer Koeniger ◽  
A. Ersin Acar ◽  
Chris Molaison ◽  
...  
Keyword(s):  
Low Temperature ◽  
Corrosion Protection ◽  
Temperature Sensitive ◽  
Powder Coatings

Dynamic Mechanical Analysis of Bio-Based and Synthetic Petroleum Based Polymer Foams with Powder Type Organic Filler at Prolonged Ultra-Violet Exposure

2020 ◽  
Vol 01 (01) ◽  
Author(s):  
M A Zulhakimie ◽  
◽  
Anika Zafiah M. Rus ◽  
N S S Sulong ◽  
A Syah Z A ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Epoxy Polymer ◽  
Loss Modulus ◽  
Ultra Violet ◽  
Mechanical Analysis ◽  
Uv Exposure ◽  
Polymer Foams ◽  
Polymer Foam ◽  
Powder Filler ◽  
Tan Δ

Wood powder filler applied to the bio-based and epoxy polymer foams has the potential to reinforce the polymer foam structure. The 'Meranti' wood filler type was used as the filler in this analysis. In order to observe the pore size of each sample when exposed to different hours of UV exposure using optical microscopy (OM), this study was made.This analysis was conducted to compare the mechanical properties of each sample with different filler ratios of 0 wt%, 5 wt%, 10 wt%, 15wt% and 20 wt% at different UV exposure hours, which is 0 hour to 6000 hours with a 2000 hour rapid increase. Using the DMA Q800 TA unit, the mechanical properties were studied. In order to obtain the product of their mechanical properties, samples having a scale of 40 x 10 x 5 mm were clamped into the machine. The results will show the value of tan δ, loss modulus and storage modulus from the DMA test.The tan δ value shows that the high tanδvalue will be produced by the higher ratio filler. In contrast to bio-based polymer foams, epoxy polymer foams with powder fillers have the highest tan δ value. It shows that the higher filler ratio can be reported with the lower tan δ value. As the filler ratio filler in the polymer foams increased, the consequence of storage and loss modulus was found to increase. The greater the modulus of loss and the modulus of storage, the lower the temperature. As energy is lost as heat during UV irradiation exposure, bio-based polymer foams with a high powder filler ratio can dissipate more energy.

scholarly journals Dynamic Mechanical Properties of Hybrid Layered Silicates/Kaolin Geopolymer Filler in Epoxy Composites

2017 ◽  
Vol 54 (3) ◽  
pp. 543-545 ◽  
Author(s):  
Yusrina Mat Daud ◽  
Kamarudin Hussin ◽  
Azlin Fazlina Osman ◽  
Che Mohd Ruzaidi Ghazali ◽  
Mohd Mustafa Al Bakri Abdullah ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
High Speed ◽  
Hybrid Composites ◽  
Loss Modulus ◽  
Dynamic Mechanical Properties ◽  
Mechanical Analysis ◽  
Layered Silicates ◽  
Epoxy Composites ◽  
Damping Factor ◽  
Dynamic Mechanical

Preparation epoxy based hybrid composites were involved kaolin geopolymer filler, organo-montmorillonite at 3phr by using high speed mechanical stirrer. A mechanical behaviour of neat epoxy, epoxy/organo-montmorillonite and its hybrid composites containing 1-8phr kaolin geopolymer filler was studied upon cyclic deformation (three-point flexion mode) as the temperature is varies. The analysis was determined by dynamic mechanical analysis (DMA) at frequency of 1.0Hz. The results then expressed in storage modulus (E�), loss modulus (E�) and damping factor (tan d) as function of temperature from 40 oC to 130oC. Overall results indicated that E�, E�� and Tg increased considerably by incorporating optimum 1phr kaolin geopolymer in epoxy organo-montmorillonite hybrid composites.

scholarly journals Dynamo-mechanical analysis of rubbers with mineral fillers in comparison with fillers widely used in the tire industry

2021 ◽  
pp. 05-13
Author(s):  
Oleg K. Garishin ◽  
◽  
Anton Y. Beliaev ◽  
Keyword(s):  
Experimental Testing ◽  
Loss Modulus ◽  
Mechanical Analysis ◽  
Operating Conditions ◽  
Styrene Butadiene Rubber ◽  
Structural Level ◽  
Butadiene Rubber ◽  
Tire Industry ◽  
Mineral Fillers ◽  
Styrene Butadiene

The work is devoted to the study of nanocomposites based on synthetic (styrene-butadiene) rubber with different fillers not previously used. The issue of using composites with alternative fillers is being investigated. The results of experimental testing and analysis of thermo-visco-elastic behav-ior of styrene-butadiene rubbers filled by various mineral particles of micro and nanosize, as well as pyrolysis products of organic food waste, are presented. The filled elastomers discussed in this work are mainly used in the tire industry to improve the performance of tires. All samples were tested on a dynamo-mechanical analyzer (DMA). Temperature and frequency dependences of the dynamic modulus and loss modulus are plotted for each of the composites. The frequency charac-teristics corresponded to the real range of rotation speeds of the car wheel, and the temperature var-ied from –50 to +50ºC. A comparative analysis of the results obtained was carried out. The struc-tural mechanisms of the filler are not investigated. It is assumed that the principles of operation of the investigated fillers at the structural level are similar to those described in many works for clas-sical fillers. Based on the test results a conclusion about the preferable operating conditions for the considered materials was made.

Gene transfer: DNA microinjection compared with DNA transfection with a very high efficiency

1982 ◽  
Vol 2 (9) ◽  
pp. 1145-1154
Author(s):  
Y M Shen ◽  
R R Hirschhorn ◽  
W E Mercer ◽  
E Surmacz ◽  
Y Tsutsui ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Line ◽  
Thymidine Kinase ◽  
Mammalian Cells ◽  
High Efficiency ◽  
Transient Gene Expression ◽  
Simian Virus 40 ◽  
Temperature Sensitive ◽  
Enzymatic Function ◽  
Very High

We have developed a procedure that gives a very high efficiency of transfection in mammalian cells with low-molecular-weight DNA (approximately 10(4) base pairs). The procedure uses cells in suspension that are shocked with polyethylene glycol 4 h after replating. We compared this transfection technique to the standard technique involving manual microinjection of DNA into the nuclei of mammalian cells, using recombinant plasmids containing the simian virus 40 A gene or the herpes simplex virus thymidine kinase gene or both. The efficiency of transfection depends on a number of variables, the most important of which is the difference in transfectability of different cell lines. In our laboratory, the cell line that had the highest efficiency of transfection was tk-ts13, which is derived from baby hamster kidney cells that are deficient in thymidine kinase and temperature sensitive for growth. Under the appropriate conditions, as many as 70% of these cells can be transfected so that transient gene expression can be detected. With the manual microinjection technique, gene expression is independent of the cell line used and occurs faster than after transfection. The results suggest that the critical stage in transfection is the delivery of DNA molecules to the nucleus. Our experiments also indicate that an enzymatic function, in our case, thymidine kinase activity, gives a higher percentage of positive transfectants than when proteins are visualized only by indirect immunofluorescence. The transfection procedure described in this paper is simple and reproducible and, although less efficient than microinjection, ought to be useful in phenotypic and genotypic studies in which transfer of genes to a large number of cells is desirable.

A kinetic model for magnetostriction of a ferrogel with physical networking

2021 ◽  
Vol 379 (2205) ◽  
pp. 20200315 ◽  
Author(s):  
A. P. Safronov ◽  
A. Yu. Zubarev ◽  
E. A. Mikhnevich ◽  
E. V. Rusinova
Keyword(s):  
Magnetic Particles ◽  
Guar Gum ◽  
Loss Modulus ◽  
Liquid Droplet ◽  
Mechanical Analysis ◽  
Strontium Hexaferrite ◽  
Theme Issue ◽  
Natural Polysaccharide ◽  
Order Of Magnitude ◽  
Kinetics Of

Kinetics of magnetostriction of ferrogel with physical networking based on natural polysaccharide guar gum with embedded strontium hexaferrite magnetic particles were studied in the uniform magnetic field 420 mT. An ellipsoidal sample was elongated by 37% along the applied field and contracted by 15% in the transverse direction, while its volume was kept constant. The characteristic time of magnetostriction was 440 s. Dynamic mechanical analysis in an oscillatory mode showed that the deformation of ferrogel is mostly elastic rather than viscous. Its storage modulus was almost constant in a frequency range of 0.1–100 Hz and by at least an order of magnitude larger than the loss modulus. Meanwhile, a developed theoretical model based on the elasto-viscous behaviour of the ferrogel failed to estimate correctly the experimental value of its magnetostriction. Calculated values of the elongation of ferrogel in the field were several orders of magnitude lower than those observed in the experiment for the ferrogel with physical networking. Consistency between the experiment and the theory was achieved using the alternative consideration based on the deformation of a liquid droplet of ferrofluid. The applicability of such an approach was discussed concerning structural relaxation properties of the ferrogel with physical networking. This article is part of the theme issue ‘Transport phenomena in complex systems (part 1)’.

scholarly journals Physical and Mechanical Properties of Ammonia-Treated Black Locust Wood

Polymers ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 377 ◽  
Author(s):  
Mariana Domnica Stanciu ◽  
Daniela Sova ◽  
Adriana Savin ◽  
Nicolae Ilias ◽  
Galina A. Gorbacheva
Keyword(s):  
Mechanical Properties ◽  
Black Locust ◽  
Loss Modulus ◽  
Colour Change ◽  
Treated Wood ◽  
Physical And Mechanical Properties ◽  
Mechanical Analysis ◽  
Modulus Of Rupture ◽  
Elastic Behaviour ◽  
Control Samples

Because of the uneven colour of black locust wood, different technologies are used to change the colour, the bestknown being chemical and thermal treatments. Some of them affect the mechanical properties of wood, such as elasticity modulus, strength, durability. This study aims to compare the physical and mechanical properties of black locust wood control samples and treated wood samples with ammonia hydroxide, in terms of density profile, colour values (CIE L*, a*, b*), mechanical properties of samples subjected to static bending, viscous-elastic properties (storage modulus (E’), loss modulus (E”) and damping (tanδ)). Two types of ammonia-fuming treatment were applied on samples: first treatment T1-5% concentration of ammonia hydroxide for 30 days; second treatment T2-10% concentration for 60 days. The results highlighted the following aspects: the overall colour change in the case of the second treatment is 27% in comparison with 7% recorded for the control samples; the lightness and yellowness values are the most affected by the second ammonia treatment of black locust wood. The density increased with almost 20% due to ammonium fuming (10% concentration/60 days); in case of static bending, the elastic modulus (MOE) tends to decrease with increasing the exposure time to ammonium, but the modulus of rupture (MOR) increases with almost 17% and the breaking force increases too, with almost 41%. In the case of dynamic mechanical analysis, the temperature leads to different viscous-elastic behaviour of each type of samples.

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