Accelerated test methods for evaluation of WB coating system comprising of epoxy primer and polyurethane top coat


Journal: Vol.10, No.2, Spring 2017 - Article 4   Pages :  93 Until 104



Article Code:
PCCC-2016-12-18-349

Authors:
A. K. Malviya: Asian Paints Ltd. - Research & Technology Center Thane-Belapur Road
S.P. Tambe: Asian Paints Ltd - Research & Technology Center Thane-Belapur Road


Article's abstract:

In corrosion protection study, it is important to develop economically attractive test method for mitigation of corrosion damage of coated structure. Faster predication of protective behavior of any coating is a big challenge for the coating industries. In present work, in-house waterborne anticorrosive coating system was selected for study. The corrosion protection of coating evaluated as per ISO12944-C3-High which includes salt spray ISO 9227, 480h and quick condensation test ISO6270, 240h. The exposure period was extended up to 1000 h for further monitoring of deterioration of selected coating system. In view of early predication of coating performance, different accelerated test exposure condition were designed in laboratory, such as; thermal aging in distilled water 50°C and 80°C, chemical immersion H2SO4 and NaOH, wet-dry cycle and thermal cycling. The corrosion protection properties of coating exposed to ISO 12944-C3-High environment was compared against the lab designed test method using electrochemical impedance spectroscopy EIS technique. The deterioration rate of coating was measured by evaluating polarization resistance Rp, water uptake w and break point frequency Fb. The coated specimens after exposure were also evaluated for loss of adhesion strength. Results showed that thermal aging in distilled water at 80°C is the most severe exposure condition as coating system loses its protective behavior in relatively short period.


Keywords:
Accelerated corrosion, Break point frequency, Crrosion, Electrochemical impedance spectroscopy, Epoxy, Waterborne coating.

References:
1. E.Almeida, D.Santos , J.Uruchurtu , Corrosion performance of waterborne coatings for structural steel,Prog.Org.Coat. ,37 (1999),131-140 2. G. Clamen,T. Ferrari, Z.Fu, , A.Hejl, G.Larson , L.Procopio, W. Rosano, A.Sheppard, A. Swartz, Protection of metal with a novel waterborne acrylic/urethane hybrid technology, Prog. Org.Coat.,72 (2011),144-151 3. M.Bethencourt, FJ. Botana,MJ. Cano, RM. Osuna, M. Marcos, Degradation mechanism of an acrylic water-based paint applied to steels, Prog. Org.Coat., 47 (2003),164-168 4. LJ.Procopio, GR. Larson, WJ. Rosano, Low-VOC Waterborne Coatings for Use in Industrial Maintenance Painting, JCT Coating Technol.,4 (2) (2007) ,50-59 5. T.Szauer,A.Brandt,Impedance measurement on zinc rich paints, JOCCA., 1 (1984), 13-17 6. M.Kendig, J.Scully, Basic Aspects of Electrochemical Impedance Application for the Life Prediction, Corros., 46 (1990), 22-29 7. SK.Singh, SP. Tambe, VS. Raja ,D. Kumar,Thermally sprayable polyethylene coatings for marine environment, Prog. Org. Coat., 60 (2007),186-193 8. D.Loveday, P. Peterson,B. Rodgers , Evaluation of Organic Coatings with Electrochemical Impedance Spectroscopy-Part 3: Protocols for Testing Coatings with EIS, JCT Coat. Tech. (2005),22-27 9. KN.Allahar, BR. Hinderliter, GP. Bierwagen, DE.Tallman, SG.Croll, Cyclic wet drying of an epoxy coating using an ionic liquid, Prog. Org. Coat., 62 (2008) 87-95 10. G.Bierwagen, D.Tallman, J.Li, L. He, C. Jeffcoate, EIS studies of Coated metals in accelerated exposure, Progress In Org. Coat. ,46 (2003),149-158 11. A.Miszczyk, T.Schauer, Electrochemical approach to evaluate the interlayer adhesion of organic coatings,Prog. Org. Coat., 52 (2005) ,298-305 12. S.Brunner, P. Richner, U. Müller,O. Guseva, Accelerated weathering device for service life prediction of organic coating,Polymer Testing, 24 (1) (2005) ,25-31 13. G.Bierwagen, D.Tallman, J.Li, L. He, C. Jeffcoate, EIS studies of Coated metals in accelerated exposure, Progress In Org. Coat. ,46 (2003),149-158 14. KN.Allahar, BR. Hinderliter, GP. Bierwagen, DE.Tallman, SG.Croll, Cyclic wet drying of an epoxy coating using an ionic liquid, Prog. Org. Coat., 62 (2008) 87-95 15. ZW.Wicks, Organic Coatings-Science


Article's file
Page view: 1056
Article's download quantity : 14


Article System Login
Introduction

Manager-in-Chief:
Prof. Zahra Ranjbar
Editor-in-Chief:
Dr. Farahnaz Nourmohammadian
Assistant Editor:
Dr. Mozhgan Hosseinnezhad
ISSN:
2008-2134
ISSN (online):
2383-1790
Publisher:
Institute for Color Science and Technology (ICST)

Quick Access
Publications
E-Vote
What is your opinion about the manuscript subscription system of PCCC website?
Excellent
Good
Fair
Poor
Website Statistics
Page view:1,057
Online Visitors:69