Natural Fiber Reinforced Granulate Coating for Injection Molding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Plastics reinforced with natural fibers exhibit higher viscosity, requiring increased pressure and volume flow rates during injection molding, leading to mechanical stress and potential fiber degradation, and resulting in components with unpleasant odors.
Innovation Solution
A process involving heat treatment of fiber-reinforced thermoplastic granulate to convert the external layer to a liquid state, followed by application of a chemical foaming agent, which is activated above its reaction temperature to reduce viscosity and prevent fiber degradation, allowing for lower pressure injection molding without mechanical stress.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If natural fibers are used to reinforce plastics, then mechanical properties are improved, but viscosity increases requiring higher pressure and volume flow rates
Solution Approach 1:
The invention changes the physical-chemical parameters of the granulate by coating natural fibers with a plastic granulate layer, transforming the surface properties to reduce friction and viscosity during injection molding, thereby lowering the required pressure and volume flow rates
Solution Approach 2:
The invention creates a composite structure where natural fibers are coated with a plastic granulate layer, forming a core-shell composite that combines the mechanical benefits of natural fibers with the flow properties of plastic, resolving the contradiction between strength improvement and viscosity increase
2Productivity
If higher pressure and volume flow rates are applied to fill the mold cavity, then filling is achieved, but internal mechanical stresses and temperatures increase causing fiber degradation
Solution Approach 1:
The coating layer on natural fibers changes the rheological parameters of the composite material, enabling mold filling at lower pressures and temperatures, thus preventing fiber degradation while maintaining productivity
Solution Approach 2:
The plastic granulate coating acts as an intermediary layer between the natural fiber and the molten plastic matrix, facilitating easier flow and reducing the mechanical stress transmitted to the fibers during injection molding
3Ease of operation
If higher temperatures are applied during injection molding, then filling is improved, but fiber degradation occurs causing unpleasant odors
Solution Approach 1:
The invention modifies the thermal parameters by using a coating layer that allows processing at lower temperatures, preventing fiber degradation and unpleasant odors while maintaining adequate filling capability through reduced viscosity
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 process produces injection-molded components with improved mechanical properties and eliminates unpleasant odors, achieving higher quality components by reducing internal mechanical stresses and maintaining fiber integrity.
Implementation Method 1
a powder made of a chemical foaming agent is applied in at least some regions or portions to each heated granulate grain, where the heat treatment is carried out such that a temperature of the liquid external layer of the respective granulate grain is below a reaction temperature of the foaming agent
Data Source
AI summary
A system for production of a thermoplastic injection molding material granulate has at least one production unit for the production of a fiber reinforced plastic granulate from a thermoplastic granulate and natural fibers. to the system has at least one heat-treatment unit for the treatment of the fiber-reinforced plastic granulate providing heat such that an outer layer of each heated granulate grain of the fiber-reinforced plastic granulate is at least partially converted to a liquid physical state. The system has at least one applicator unit for applying a chemical foaming agent powder to at least some portions of each heated granulate grain, where the heat treatment unit is equipped to carry out the heat treatment such that a temperature of the molten outer layer of the respective granulate grain is below a reaction temperature of the foaming agent.