Polyfunctional Bridging Molecules for Corrosion Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current coating processes for metallic substrates rely on inorganic compounds like phosphates and chromates, which raise environmental concerns, and require acidic conditions, while seeking to enhance the binding of organic coating resins to substrates at neutral or alkaline pH.
Innovation Solution
The use of polyfunctional bridging molecules that react with resin functional groups to form products like Michael additions, enamines, hydrazones, reductive amination products, or amides, allowing direct binding to metallic substrates without pre-treatments, utilizing chelating groups such as carboxylates, thiols, and silanes to chelate metals, and incorporating group IVB and VB elements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If inorganic compounds like phosphates and chromates are used for pre-treatment, then corrosion resistance and binding are improved, but environmental harm increases
Solution Approach 1:
The invention extracts and removes the harmful inorganic components (phosphates and chromates) from the pre-treatment process, replacing them with environmentally benign organic compounds that achieve the same protective function without the environmental harm
Solution Approach 2:
The invention changes the chemical composition parameters from inorganic phosphates and chromates to organic compounds containing functional groups like carboxylic acids, hydroxyls, and amines, fundamentally altering the chemical nature of the pre-treatment while maintaining its protective function
2Reliability
If acidic conditions are used for pre-treatment, then binding of coating resin to substrate is improved, but process complexity and environmental impact increase
Solution Approach 1:
Instead of using acidic conditions to achieve binding, the invention inverts the approach by using neutral or alkaline conditions with organic compounds that form protective films through different chemical mechanisms, eliminating the need for acidic environments
Solution Approach 2:
The invention introduces organic compounds as intermediary substances that mediate between the substrate and coating resin, forming a protective film that facilitates binding without requiring acidic conditions, thus simplifying the overall process
3Reliability
If multiple pre-treatment steps are used, then coating binding is improved, but manufacturing time and process complexity increase
Solution Approach 1:
The invention merges multiple separate pre-treatment steps into a single integrated organic compound treatment process, where one application achieves what previously required sequential phosphate treatment, chromate conversion, and other steps, thereby reducing total process time
Solution Approach 2:
The organic compounds used in the invention possess multiple functions within a single substance: they clean the substrate, form a protective film, and promote coating adhesion, eliminating the need for separate specialized treatments for each function
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach eliminates the need for pre-treatments like phosphating, provides effective corrosion protection comparable to chrome-based coatings, and enhances the binding of organic coating resins to metallic substrates at neutral or alkaline pH, offering a more environmentally friendly and versatile coating process.
Implementation Method 1
at least a portion of said second functional groups have reacted with at least a portion of said first functional groups to form one of a Michael addition product, an enamine, a hydrazone, a reductive amination product, or an amide thereby binding at least a portion of said polyfunctional bridging molecules to said resin
Implementation Method 2
reaction products of a polymeric resin having a plurality of first functional groups with a plurality of polyfunctional bridging molecules
Implementation Method 3
said third functional group is selected from the group consisting of a carboxylate function, a thiol function, a silane function, a phenolate function, an acetoacetonate function, an imine function, a phosphate function, a phosphonate function and mixtures thereof, wherein said third functional group can chelate to a metal substrate
Data Source
Figure 1
AI summary
Disclosed is a method for providing an anti -corrosion protective coating to a metal substrate that uses a coating composition comprising a resin and a polyfunctional bridging molecule to both bind to the resin and to chelate the bound polymeric resin directly to the metal substrate. One category of polyfunctional bridging molecules preferably includes at least one amine function to bind to a resin and at least one carboxylate, thiol, silane, phenolate, acetoacetonate, imine, phosphate, or phosphonate function to chelate to a metal substrate. It is theorized that the amine function can bind to certain pendent chains in coating resins through a Michael addition reaction while the carboxylate, thiol, silane, phenolate, acetoacetonate, imine, phosphate, or phosphonate functions chelate to the metal substrate. These polyfunctional bridging molecules provide an organic binding of the resin to the metal substrates.