Thiol-Modified Epoxy Steel Pipe Coating
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing coating methods for steel pipes face issues with slow curing rates, inferior durability and impact resistance, and sensitivity to humidity, while also generating dust and having low adhesion and airtightness due to the use of inorganic materials, polyurethane, or polyurea coatings.
Innovation Solution
An eco-friendly adhesive coating agent composition utilizing a thiol-modified epoxy intermediate, which combines with polyoxypropyleneamine, a cross-linking agent, inorganic filler, pigment, and additives in the main material, and a rubber-modified epoxy resin, polyol, and additives in the curing agent, to achieve fast-curing and high adhesion properties, even under low temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If epoxy resin is used alone for coating steel pipes, then adhesion properties and mechanical strength are improved, but curing rate becomes slow and heat treatment is required
Solution Approach 1:
The patent combines epoxy resin with polyisocyanate and polyol to create a composite coating system that integrates the advantages of multiple materials. The epoxy resin provides adhesion and mechanical strength, while the polyisocyanate-polyol system contributes to faster curing and flexibility, resolving the contradiction between strength and curing rate.
Solution Approach 2:
The invention uses a composite material system consisting of epoxy resin, polyisocyanate, and polyol in specific ratios. This composite approach allows the coating to exhibit both the high adhesion of epoxy resin and the fast-curing properties of polyurethane/polyurea systems, eliminating the need for heat treatment while maintaining superior bonding.
2Strength
If polyurethane is used for coating steel pipes, then adhesion is improved, but curing rate becomes slow and sensitivity to humidity increases causing bubbles
Solution Approach 1:
The patent modifies the chemical composition parameters by using polyisocyanate with specific NCO content (20-40%) and controlling the ratio of polyisocyanate to polyol (1:1 to 2:1). These parameter adjustments optimize the curing rate while maintaining adhesion, preventing bubble formation by controlling the reaction kinetics and moisture sensitivity.
3Reliability
If polyurea is used for coating steel pipes, then stability to humidity is improved, but curing rate becomes too fast causing inferior airtightness and adhesion
Solution Approach 1:
The patent uses polyisocyanate in a controlled excess relative to polyol (ratio of 1:1 to 2:1), which allows the coating to achieve good adhesion and airtightness while maintaining humidity stability. The controlled excess ensures complete reaction with moisture for crosslinking while preventing overly rapid curing that would compromise quality.
4Strength
If inorganic materials are used in coating composition, then mechanical properties are improved, but dust is generated during application under high temperature and high pressure
Solution Approach 1:
The patent employs a flexible polymer matrix (epoxy resin combined with polyisocyanate and polyol) that can encapsulate and bind inorganic fillers effectively. This flexible binding mechanism reduces dust generation during application by preventing filler particle detachment, while still providing enhanced mechanical properties through the inorganic reinforcement.
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
The composition exhibits excellent adhesion and fast-curing properties, improving mechanical strength and durability, and is suitable for steel pipe coatings without generating harmful substances or compromising airtightness.
Implementation Method 1
epoxy resins may be used in combination with a curing agent, such as polyamine or polyamide, rather than being used alone to form a cured coating film by crosslinking
Implementation Method 2
An eco-friendly adhesive coating agent composition utilizing a thiol-modified epoxy intermediate, which combines with polyoxypropyleneamine, a cross-linking agent, inorganic filler, pigment, and additives in the main material, and a rubber-modified epoxy resin, polyol, and additives in the curing agent, to achieve fast-curing and high adhesion properties
Data Source
AI summary
Disclosed is an eco-friendly adhesive coating agent composition having high adhesion properties and fast-curing properties by using a thiol-modified epoxy intermediate. The composition includes: a main material including 25 to 40 parts by weight of polyoxypropyleneamine, 20 to 30 parts by weight of a cross-linking agent, 10 to 30 parts by weight of the thiol-modified epoxy intermediate, 10 to 20 parts by weight of an inorganic filler, 5 to 10 parts by weight of a pigment, and 2 to 5 parts by weight of an additive; and a curing agent including 60 to 80 parts by weight of a rubber-modified epoxy resin, 20 to 40 parts by weight of a polyol, 10 to 30 parts by weight of the thiol-modified epoxy intermediate, and 4 to 10 parts by weight of an additive, with respect to 100 parts by weight of an isocyanate mixture.