Prepreg Welding Strength via Thermoplastic Resin Layer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for joining fiber-reinforced composite materials with thermosetting and thermoplastic resins face challenges such as prolonged production processes, inadequate joining strength, especially in high temperature and high humidity environments, and insufficient interlaminar fractural toughness.
Innovation Solution
A prepreg comprising reinforcing fibers embedded in a thermosetting resin with a crystalline or amorphous thermoplastic resin having a high glass transition temperature, applied on the surface or between layers, allowing for improved welding and integration with other members, enhancing tensile shear joining strength and fatigue resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If mechanical joining methods (bolts, rivets, screws) are used to integrate fiber-reinforced composite materials, then the joining strength is improved, but the production process is prolonged and production cost is increased due to preliminary processing such as drilling
Solution Approach 1:
The patent combines thermosetting resin and thermoplastic resin in a single prepreg structure, allowing simultaneous achievement of strong bonding and welding capability. The thermosetting resin provides adhesive bonding strength while the thermoplastic resin enables welding, eliminating the need for separate mechanical joining processes and preliminary drilling operations.
Solution Approach 2:
The patent utilizes the phase change properties of the thermoplastic resin (melting and solidification) to enable welding. By controlling temperature parameters, the thermoplastic resin transitions between solid and molten states, allowing for efficient welding operations that are both fast and strong, unlike mechanical joining which requires multiple discrete steps.
2Ease of manufacture
If adhesive joining method is used to integrate fiber-reinforced composite materials, then the production process is simplified, but the production process is prolonged due to bonding preparation, coating, and curing processes, and sufficient reliability in bonding strength cannot be obtained
Solution Approach 1:
The patent exploits the phase transition of thermoplastic resin from solid to molten state during welding. This phase change enables rapid joining without the prolonged curing process required for adhesives. The thermoplastic resin melts during welding and solidifies to form a strong joint, eliminating the need for separate bonding preparation, coating, and curing steps.
3Productivity
If thermoplastic resin is used as matrix for fiber-reinforced composite materials, then welding method can be applied to shorten joining time, but heat resistance and chemical resistance are insufficient compared to thermosetting resin composites
Solution Approach 1:
The patent creates a composite resin system combining thermosetting resin and thermoplastic resin within the same prepreg structure. The thermosetting resin matrix provides excellent heat resistance and chemical resistance, while the thermoplastic resin components enable welding capability. This composite approach allows simultaneous achievement of short joining time through welding and high reliability through the thermosetting resin's resistance properties.
4Ease of manufacture
If conventional prepreg structure with uniform resin distribution is used, then manufacturing is simplified, but interlaminar fractural toughness is insufficient
Solution Approach 1:
The patent implements non-uniform distribution of thermoplastic resin within the prepreg structure, with higher concentrations at the surfaces and between layers. This local quality enhancement provides improved interlaminar fractural toughness and surface properties for welding, while maintaining manufacturing simplicity through a systematic resin distribution pattern rather than complex multi-step processes.
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 solution enables efficient joining and integration of composite materials with excellent mechanical properties at room temperature and in high temperature and high humidity environments, reducing production time and costs while maintaining structural integrity.
Implementation Method 1
a crystalline thermoplastic resin having a glass transition temperature of 100° C. or higher or an amorphous thermoplastic resin having a glass transition temperature of 180° C. or higher
Implementation Method 2
a thermosetting resin or a thermoplastic resin is used as a matrix
Data Source
AI summary
The present invention aims at providing a prepreg for producing a laminate suitable as a structural material, and a laminate, which have excellent tensile shear joining strength, fatigue joining strength, and interlaminar fractural toughness values, and can be firmly integrated with another structural member by welding. The present invention is a prepreg including the following structural components [A], [B], and [C], wherein [C] is present on a surface of the prepreg, [C] is a crystalline thermoplastic resin having a glass transition temperature of 100° C. or higher or an amorphous thermoplastic resin having a glass transition temperature of 180° C. or higher, and the reinforcing fibers [A] are present which are included in a resin area including [B] and a resin area including [C] across an interface between the two resin areas: [A] reinforcing fibers; [B] a thermosetting resin; and [C] a thermoplastic resin.