Hybrid Yarn Coating for PVC Fiber Reinforcement
Solution Overview
Problem
Existing methods for reinforcing PVC profiles with fibers, such as glass fibers, face challenges including poor adhesion between fibers and the PVC matrix, high machine wear, and significant reduction in fiber length due to shear forces, leading to suboptimal mechanical performance and increased costs.
Innovation Solution
The use of a hybrid yarn containing reinforcing fibers and a plastic material with high binding affinity to PVC, such as polyester, which is preheated to melt and then coated with PVC, creating a strong bond and protecting the fibers during the extrusion process, thereby reducing fiber shortening and machine wear.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If dry reinforcing fibers are directly processed with PVC, then fiber reinforcement is achieved, but machine wear increases significantly
Solution Approach 1:
The patent introduces a plastic material (such as polyester) as an intermediary substance that coats the reinforcing fibers before they are incorporated into the PVC matrix. This intermediary layer reduces direct contact and friction between the dry fibers and machine components, thereby significantly reducing machine wear while maintaining the reinforcement effect.
2Strength
If dry reinforcing fibers are directly processed with PVC, then fiber reinforcement is achieved, but fiber length is significantly reduced due to shear forces
Solution Approach 1:
The plastic material coating acts as a protective intermediary layer around the reinforcing fibers during processing. This layer cushions the fibers against direct shear forces generated during mixing and extrusion, preserving fiber length and preventing excessive comminution that would otherwise occur with direct fiber-PVC contact.
Solution Approach 2:
The reinforcing fibers are pre-coated with plastic material before being incorporated into the PVC matrix. This preliminary coating action prepares the fibers for subsequent processing by providing protection against shear forces, ensuring they maintain their length and reinforcement effectiveness throughout the extrusion process.
3Strength
If dry reinforcing fibers are directly processed with PVC, then fiber reinforcement is achieved, but adhesion between fibers and PVC matrix is poor
Solution Approach 1:
The plastic material coating serves as a chemical and physical intermediary between the reinforcing fibers and the PVC matrix. It provides functional groups and surface properties that enhance bonding compatibility, creating strong interfacial adhesion between the otherwise incompatible fiber-PVC interface and improving overall composite reliability.
4Reliability
If hybrid yarn with plastic material coating is used, then fiber protection and adhesion are improved, but processing complexity increases
Solution Approach 1:
The hybrid yarn is pre-manufactured with the plastic material coating already applied to the reinforcing fibers. This preliminary preparation consolidates multiple steps (fiber coating, yarn formation) into a single ready-to-use material, simplifying the overall processing procedure while maintaining the adhesion and protection benefits.
Solution Approach 2:
The invention uses a composite hybrid yarn structure combining reinforcing fibers and plastic material in a predetermined configuration. This composite approach integrates multiple functions (reinforcement, adhesion promotion, fiber protection) into a single material component, reducing the need for separate processing steps and apparatus.
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 results in PVC profiles with enhanced mechanical performance, reduced fiber shortening, and lower machine wear, while maintaining a strong bond between fibers and the PVC matrix, enabling the production of cost-effective, high-performance PVC long-fiber thermoplastics.
Implementation Method 1
a plastic material with high binding affinity to PVC, such as polyester, which is preheated to melt and then coated with PVC
Implementation Method 2
The plastic material, which on the one hand has a high binding affinity to PVC and on the other hand also adheres well to the reinforcing fibers
Data Source
Figure 1a~1c
Figure 2a~2d
Figure 3
AI summary
The invention relates to a method for producing a PVC long fibre thermoplastic, in which initially at least one hybrid yarn (3) containing reinforcement fibers (1) as well as plastic material (2) is produced. Said plastic material (2) is selected in such a way that it has a high binding affinity with PVC and in which the hybrid yarn (3) is covered with PVC, preferably in the way of an extrusion method and based on the high binding affinity of the plastic material (2) is internally connected to the PVC covering (6).