Developing Practical Applications of Phosphonic Acid Skanda Amarnath, Matthew Chalkley, Rachel Chen, Reena Clements, Kevin Gu, Gawain Lau, Stephen Leh, Sarvagna Patel, Mark Vander Schaaf, Phyllis Schlafly, Smith Shah Advisor: Michael Avaltroni Assistant: Jennifer Cowell

Octadecylphosphonic Acid (OPA) Bonds easily to many surfaces 1 Bonds easily to many surfaces 1 Creates a durable hydrophobic layer that adheres to hydrophilic surfaces Creates a durable hydrophobic layer that adheres to hydrophilic surfaces Bonds chemically rather than physically Bonds chemically rather than physically 1 Maege I, Jaehne E, Henke A, Adler H.-JP, Bram C, Jung C, Stratmann M Self-assembling adhesion promoters for corrosion resistant metal polymer interfaces. Progress in Organic Coatings. 34: 1-12.

The Structure of OPA Schreiber F. Dec Structure and growth of self-assembling monolayers. Progress in Surface Science [cited 16 July 2008] 65: &_user=799667&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C &_version=1&_urlVersion=0&_u serid=799667&md5=274b633832f0a166f28f2213b36a4ad5 Diprotic acid Both protons are acidic Octadecyl alkyl group increases hydrophobicity

Oxide Surfaces O MM O M µ-oxo Group Hydroxyl Group OH M M M

Octadecylphosphonic Acid Bonding to an Oxide Layer Schreiber F. Dec Structure and growth of self-assembling monolayers. Progress in Surface Science [cited 16 July 2008] 65: &_user=799667&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C &_version=1&_urlVersion=0&_userid=799667&md5=274b633832f0 a166f28f2213b36a4ad5

Purpose To investigate the effectiveness of OPA in: To investigate the effectiveness of OPA in: Repelling water and residue buildup 3 Repelling water and residue buildup 3 Contact Angle, Surface Adhesion Contact Angle, Surface Adhesion Irreversible attaching to a surface 4 Irreversible attaching to a surface 4 Attenuated Total Reflectance Attenuated Total Reflectance Resisting corrosion Resisting corrosion Electrochemical Cell, Salinity, Acidity 3 Freedman LD, Doak GO The Preparation and Properties of Phosphonic Acid. University of North Carolina Press. 4 Schreiber F. Dec Structure and growth of self-assembling monolayers. Progress in Surface Science [cited 16 July 2008] 65: Available from: search&_sort=d&view=c&_acct=C &_version=1&_urlVersion=0&_userid=799667&md5=274b633832f0a166f28f2213b36a4ad5

Hypothesis An OPA coating will repel unwanted materials and act as a barrier to corrosion An OPA coating will repel unwanted materials and act as a barrier to corrosion

Methods and Materials Three materials were considered: Three materials were considered: Glass Glass Copper Copper Stainless Steel (Grade 316L) Stainless Steel (Grade 316L) They were coated using a “spray and spread” method 5 They were coated using a “spray and spread” method 5 Exposed to solutions of varying pHs, as well as material-specific situations Exposed to solutions of varying pHs, as well as material-specific situations 5 Appicella T, et al Phosphonic Acid: A Zero-Energy Approach to Teflon Replacement. New Jersey Governor’s School of the Sciences. [cited 17 July 2008]..

WD-40 ® Used for comparison Used for comparison Cleaner/lubricant/protectant Cleaner/lubricant/protectant Aerosol Aerosol Greasy Greasy Not permanent – physical bond Not permanent – physical bond

Contact Angle Tests A goniometer measures the hydrophobicity of a surface A goniometer measures the hydrophobicity of a surface Greater angles imply that the surface has greater hydrophobicity Greater angles imply that the surface has greater hydrophobicity θ θ

Average Contact angle(degrees) (Results after 7 days) Effectiveness of Stainless Steel Coatings

Average Contact angle (degrees)(degrees) (Results after 7 days) Effectiveness of Copper Coatings

Test Results for Acids Qualitative data based on appearance Qualitative data based on appearance Corrosion scaled from 0 to 5, with 0 being no corrosion and 5 being most corroded Corrosion scaled from 0 to 5, with 0 being no corrosion and 5 being most corroded ControlOPAWD-40 pH pH 3420 pH pH 4500 pH 7000

Salinity Test OPA-coated steel was placed in a saline solution, simulating average salt content of ocean’s surface OPA-coated steel was placed in a saline solution, simulating average salt content of ocean’s surface Simulates steel-hulled ship in ocean Simulates steel-hulled ship in ocean

Salinity Test Results

ASTM Test for Surface Adhesion “Sharpie Test” “Sharpie Test” Sharpie markers were used to simulate residue buildup Sharpie markers were used to simulate residue buildup Glass and copper samples with different coatings were marked and wiped Glass and copper samples with different coatings were marked and wiped

Sharpie Test Results - Glass Sharpie on slides before Sharpie on slides before wiping

Sharpie Test Results - Glass Sharpie on slides after wiping

Sharpie Test Results - Glass Sharpie on slides with ethanol treatment after wiping

Sharpie Test Results - Copper Sharpie on copper before wiping with dry paper towel

Sharpie on copper after wiping with paper towel Sharpie Test Results - Copper

Electrochemical Cells Cu V Zn Zn 2+, Cl - Cu 2+, SO 4 2- NH 4 + NO 3 -

Electrochemical potential (V) Resulting Voltages

Attenuated Total Reflectance (ATR) Test An ATR test analyzes the chemical composition of a surface An ATR test analyzes the chemical composition of a surface Measures amount of OPA on surface Measures amount of OPA on surface PerkinElmer, Inc. “FT-IR Spectroscopy: Attenuated Total Reflectance (ATR).” [cited 22 July 2008].. Surface

ATR Test Results Copper, OPA coated, pH

Conclusion OPA will be a suitable replacement for current coating OPA will be a suitable replacement for current coating

Conclusion - Results Corrosion Resistance Electrochemical cells Salinity Acid Durability ATR Hydrophobicity Contact Angle Adhesion Resistance Sharpie Test

Conclusion – Further Tests Polar/Non-Polar Wash Polar/Non-Polar Wash Confirm results in acid/contact angle Confirm results in acid/contact angle Longer Duration Tests Longer Duration Tests Simulate consumer conditions Simulate consumer conditions

Acknowledgements Dr. Michael Avaltroni Jennifer Cowell NJGSS 2008 Staff: Dr. David Miyamoto, Dr. Steven Surace, Dr. Paul Quinn, Myrna Papier, professors, and counselors

Special Thanks to… The many alumni and parents who donated, especially Laura and John Overdeck Schering-Plough Foundation Novartis The Dorr Foundation The Jennifer A. Chalsty Foundation The Edward W. & Stella C. Van Houten Memorial Fund The Jewish Communal Fund

Questions?