Fiber Sizing Composition for Radiation-Cured Composite Adhesion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Composite materials made with resins polymerized by light or ionizing radiation exhibit insufficient adhesion between reinforcing fibers and the organic matrix, leading to inferior transverse mechanical properties compared to thermally polymerized resins, despite existing surface treatments and sizing agents.
Innovation Solution
A sizing composition for reinforcing fibers comprising an epoxidized polybutadiene prepolymer, a crosslinking agent with thiol functions, and a tertiary amine catalyst is applied to enhance adhesion by forming a homogeneous elastomeric film that initiates polymerization and forms covalent bonds with the matrix, improving the fiber-matrix interface.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If conventional surface treatments (chemical oxidation, plasma, electrolysis) are applied to reinforcing fibers, then fiber adhesion to thermally polymerized resin matrices is improved, but adhesion to light-radiation or ionizing radiation polymerized matrices remains insufficient
Solution Approach 1:
The invention changes the chemical parameters of the fiber surface by introducing specific functional groups (carboxyl, hydroxyl, amine) through controlled oxidation and grafting treatments. These parameter changes enable the fiber surface to be compatible with both thermal and radiation-induced polymerization processes, resolving the contradiction between optimizing for thermal polymerization and maintaining versatility with radiation polymerization
Solution Approach 2:
The invention creates a composite surface structure on the fibers by combining multiple functional groups and coating layers with distinct properties. This composite surface architecture provides both the chemical reactivity needed for thermal polymerization and the radical-generating capability for radiation polymerization, achieving broad adaptability across different polymerization methods
2Strength
If complex polymer sizing agents are deposited on fiber surfaces to improve resin compatibility and impregnation, then fiber-matrix bonding is enhanced, but transverse mechanical properties remain mediocre due to insufficient chemical reactivity with radiation-polymerized matrices
Solution Approach 1:
The invention extracts and isolates the essential functional groups (carboxyl, hydroxyl, amine) from complex polymer sizing agents, using these simple functional groups as the primary active components for achieving both resin compatibility and chemical reactivity with radiation-polymerized matrices, thereby reducing complexity while maintaining effectiveness
Solution Approach 2:
The functional groups on the fiber surface act as intermediaries that mediate between the fiber and the resin matrix. These intermediary groups can participate in both thermal polymerization reactions and radiation-induced radical reactions, providing a universal interface that simplifies the overall system while achieving strong bonding and improved transverse mechanical properties
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 solution significantly increases the adhesion between reinforcing fibers and the organic matrix, enhancing the transverse mechanical properties of composite materials, particularly when the matrix is polymerized by chain transfer mechanism.
Implementation Method 1
improve the adhesion of these fibers with respect to an organic matrix forming with them a part of a composite material and resulting from chain transfer polymerization of a curable resin
Implementation Method 2
a catalyst comprising at least one tertiary amine function
Data Source
Figure 1A~1B
Figure 2A~2C
Figure 3
AI summary
The invention relates to a sizing composition for reinforcing fibres, which makes it possible to improve the adhesion of these fibres with respect to an organic matrix that forms, with them, a part made of a composite material and that results from the chain transfer polymerization of a curable resin, and also to applications of this composition. The sizing composition comprises a polybutadiene prepolymer comprising at least two epoxide functions, a crosslinking agent comprising at least two reactive functions, at least one of which is a thiol function, and a catalyst comprising at least one tertiary amine function. Fields of use: aeronautical, aerospace, railway, naval and motor vehicle industries, for example for the production of structural, engine, passenger compartment or body work parts; arms industry, for example for the production of parts incorporated into the composition of missiles or missile launch tubes; sports and leisure goods industry, for example for the production of goods intended for water sports and board sports.