Regenerated ETPU Foamed Particles Viscosity Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Waste Expanded Thermoplastic Polyurethane (ETPU) materials that have aged or been discarded for a long time often have deteriorated physical properties, making direct recycling challenging, and the resulting regenerated products' properties can vary significantly from batch to batch, complicating quality control.
Innovation Solution
A method involving the selection and sorting of waste ETPU materials, followed by remelting, pelletizing, and foaming, with the addition of TPU prepolymer to achieve specific viscosity ranges, and subsequent microwave bonding to form regenerated foamed and molded bodies.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If waste ETPU materials are directly recycled by melting, then recycling process is simple, but physical properties deteriorate and quality control becomes difficult
Solution Approach 1:
The patent applies parameter changes by controlling the viscosity of regenerated TPU particles within a specific range (1,000 to 9,000 poise at 170°C) through the addition of TPU prepolymer. This viscosity control ensures consistent foaming behavior and product quality, resolving the quality control issues while maintaining a relatively simple recycling process.
Solution Approach 2:
The patent introduces TPU prepolymer as an intermediary substance to modify the recycled TPU particles. The prepolymer acts as a mediator that improves the viscosity and processability of aged waste ETPU materials, enabling consistent quality regeneration without significantly complicating the manufacturing process.
2Quantity of substance
If aged waste ETPU materials are used, then recycling cost is reduced, but physical properties deteriorate significantly
Solution Approach 1:
The patent changes the chemical parameter of the recycled material by adding TPU prepolymer, which restores the viscosity and physical properties of aged waste ETPU materials. This allows the use of aged materials (increasing quantity utilization) while maintaining reliable physical properties through viscosity control in the 1,000 to 9,000 poise range.
Solution Approach 2:
The patent converts the harmful effect of aging (deteriorated physical properties) into a manageable parameter by adding prepolymer. The aging process is no longer a disqualifying factor but becomes a variable that can be compensated for through controlled prepolymer addition, turning a disadvantage into an acceptable input material range.
3Manufacturing precision
If TPU prepolymer is added to control viscosity, then product quality consistency improves, but manufacturing complexity increases
Solution Approach 1:
The patent uses parameter changes (viscosity control through prepolymer addition) to achieve consistent product quality. The complexity is managed by establishing a clear viscosity target range (1,000 to 9,000 poise at 170°C) and adjusting prepolymer content accordingly, making the process controllable despite the added step.
4Reliability
If waste ETPU materials are sorted and selected, then regeneration success rate increases, but processing time increases
Solution Approach 1:
The patent applies preliminary action by sorting and selecting waste ETPU materials before the regeneration process. This preliminary classification ensures that only suitable materials enter the recycling process, increasing success rates while allowing the subsequent manufacturing steps to proceed efficiently without rework from failed batches.
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 allows for the successful regeneration of foamed and molded bodies with consistent properties, overcoming the issues of property deterioration and batch variability in recycled ETPU materials, enabling the production of high-quality recycled products.
Implementation Method 1
bonding the regenerated foamed particles through microwaves to form the regenerated foamed and molded body
Data Source
AI summary
Regenerated foamed particles, and a regenerated foamed and molded body made from same. The regenerated foamed particles are made by melting and foaming regenerated TPU particles. The regenerated TPU particles are formed by melting and pelletizing a recycled composition which contains 100 parts by weight of scraps of a waste ETPU molded body and 0 to 20 parts by weight of a TPU prepolymer. The regenerated TPU particles have a viscosity of 1,000 to 9,000 poises measured at 170° C. according to the JISK7311 method.