Micro-crosslinked Thermoplastic Polyurethane Extrusion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for extruding modified thermoplastic polyurethanes face challenges such as high chemical crosslinking leading to gel formation or extruder blocking, limiting the production of cost-effective, high-speed elastic thermoplastic polyurethane materials with improved tensile strength and elongation.
Innovation Solution
The development of micro-crosslinked thermoplastic polyurethanes using a polyurethane backbone and a crosslinker comprising a functional polyolefin, which allows for extrudability without gelation, enhancing tensile strength and elongation while maintaining melt processability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If high degree of chemical crosslinking is imparted through modification, then tensile strength and elongation are improved, but gelling or blocking of the extruder occurs during high speed extrusion processes
Solution Approach 1:
The patent changes the crosslinking degree parameter from high to low (micro-crosslinking), transforming the material properties to achieve both improved strength and maintain extrudability. This parameter change resolves the contradiction by finding an optimal intermediate state that satisfies both requirements.
Solution Approach 2:
The patent applies partial crosslinking (micro-crosslinking) rather than complete or excessive crosslinking. This partial action provides sufficient strength improvement while avoiding the gelation and extruder blocking that result from excessive crosslinking.
2Productivity
If high speed extrusion process is used, then productivity is improved, but gel formation or extruder blocking occurs due to chemical crosslinking
Solution Approach 1:
The patent changes the crosslinking degree parameter to enable high speed extrusion without gel formation. The micro-crosslinked structure maintains process stability at high extrusion speeds by preventing the gelation that would otherwise occur.
3Stability of the object's composition
If thermoset polyurethane is used to achieve excellent elasticity, then elastic properties are improved, but melt processability is lost due to chemically crosslinked nature
Solution Approach 1:
The patent changes the crosslinking degree from complete (thermoset) to micro-crosslinking (thermoplastic), enabling both excellent elasticity and melt processability. This parameter transformation allows the material to be extruded while maintaining superior elastic 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
The micro-crosslinked thermoplastic polyurethanes exhibit significantly improved tensile strength and elongation, making them suitable for various consumer products, including elastic articles, without the issues of gelation during extrusion, thus addressing the limitations of existing technologies.
Implementation Method 1
The polymer including a polyurethane backbone, specifically the polyurethane linkage of the polyurethane backbone, reacts with the crosslinker including a functional polyolefin during the method step of extruding the mixture
Data Source
AI summary
Described herein are modified thermoplastic polyurethanes, methods of reactively extruding the modified thermoplastic polyurethanes, and methods of using the modified thermoplastic polyurethanes. The modified thermoplastic polyurethanes are micro-crosslinked through reaction with a functional polyolefin, have significantly improved tensile strength and elongation compared to unmodified thermoplastic polyurethanes, and may be extruded.