Silicate-Modified Epoxy Coating for Low VOC and Fast Curing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Coating compositions with high solvent content and low solids content face challenges in reducing volatile organic solvent emissions, particularly when applied and cured rapidly at ambient temperature, as they require low viscosity and long curing times to develop mechanical properties, which is impractical for large structures like ships and bridges.
Innovation Solution
A silicate-modified epoxy resin composition is developed, comprising a reaction product of tetra-alkoxyorthosilicate and epoxy resin with hydroxyl groups, achieving high solids content (>70 vol%) and low volatile organic content (<250 g/l), allowing for fast curing at ambient and sub-ambient temperatures without additional solvents, and extending pot life.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If coating compositions contain high solvent content to achieve low viscosity for rapid application, then ease of operation is improved, but volatile organic solvent emissions increase and solids content decreases
Solution Approach 1:
The invention changes the chemical composition parameters by incorporating silicate-modified epoxy resin with specific molecular weight and hydroxyl value ranges, replacing conventional polymer-solvent systems. This parameter change enables the coating to achieve both low viscosity (for ease of application) and high solids content (reducing VOC emissions) simultaneously, resolving the technical contradiction between ease of operation and harmful emissions
Solution Approach 2:
The invention uses a composite resin system combining silicate-modified epoxy resin with specific polymers and curing agents. This composite material approach allows the formulation to achieve contradictory properties: low viscosity for spray application while maintaining high solids content to reduce VOC, as the silicate-modified epoxy provides both flow properties and structural integrity without requiring high solvent levels
2Ease of operation
If coating compositions use low molecular weight polymers to achieve low viscosity, then ease of operation is improved, but curing time increases to develop mechanical properties
Solution Approach 1:
The invention optimizes the molecular weight parameter of the silicate-modified epoxy resin to a specific range (500-10,000) and hydroxyl value (20-100 mg KOH/g), creating a balance between viscosity and curing rate. This parameter optimization ensures low viscosity for easy application while maintaining sufficient reactivity for fast curing, resolving the contradiction between ease of operation and curing time
Solution Approach 2:
The silicate-modified epoxy resin acts as an intermediary component that mediates between the polymer and curing agent. Its specific chemical structure with silicate groups and hydroxyl functionalities facilitates rapid crosslinking reactions while maintaining low viscosity, enabling fast cure times without sacrificing application properties
3Productivity
If coating compositions are cured at ambient temperature for rapid deployment, then productivity is improved, but mechanical properties deteriorate with conventional formulations
Solution Approach 1:
The invention changes the chemical parameters of the epoxy resin system by using silicate-modified epoxy with specific molecular weight and hydroxyl value ranges, combined with appropriate curing agents. This parameter change enables the coating to cure rapidly at ambient temperature while developing satisfactory mechanical properties, resolving the contradiction between productivity and strength that plagues conventional low-temperature curing systems
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 silicate-modified epoxy resin composition achieves fast curing and high solids content, reducing the need for solvents and extending pot life, making it suitable for rapid application and curing on large structures while maintaining mechanical properties and adhesion.
Implementation Method 1
a silicate-modified epoxy resin obtainable by dealcoholisation condensation of a bisphenol epoxy resin - i.e. an aromatic epoxy resin - and a hydrolysable alkoxysilane
Implementation Method 2
the reaction product of a tetra-alkoxyorthosilicate or a partially condensed oligomer thereof and an epoxy resin containing hydroxyl groups
Data Source
AI summary
Coating composition comprising the reaction product of a tetra-alkoxyorthosilicate or a partially condensed oligomer thereof and an epoxy resin containing hydroxyl groups, said coating composition having a solids content of at least 70 vol% and/or a volatile organic content (VOC) not exceeding 250 g/l. This coating composition gives fast curing at ambient and sub-ambient temperatures and an extended pot life.