Layered Foamed Polymeric Materials With Gradient Density
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for creating layered foamed materials with uniform density and morphology gradients are complex, laborious, and often result in discontinuities at layer interfaces, limiting their industrial applicability and design flexibility.
Innovation Solution
A process involving variable conditions over time during the solubilization of foaming agents in polymers, using pressure, gas composition, and temperature variations to create non-uniform agent profiles, which upon foaming, generate multi-layer structures with gradual density and morphology variations without interface discontinuities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If constant pressure and temperature conditions are used during solubilisation, then uniform foamed structure is obtained, but design flexibility and functional performance are limited
Solution Approach 1:
The patent applies dynamics by transitioning from static (constant) to dynamic (variable) solubilisation conditions. The pressure and temperature are varied over time during the solubilisation process, creating non-uniform concentration profiles of the foaming agent that result in layered foamed structures with different densities and morphologies. This dynamic approach enables design flexibility while maintaining a single-step process.
Solution Approach 2:
The patent implements parameter changes by systematically varying pressure and temperature parameters during solubilisation. By changing these physical parameters over time, the concentration distribution of the foaming agent is controlled, enabling the creation of multi-layer structures with tailored properties without increasing overall process complexity.
2Reliability
If multiple separate foamed layers are assembled to create gradient structures, then functional performance is improved, but manufacturing complexity and interface discontinuities increase
Solution Approach 1:
The patent merges multiple foamed layers into a single continuous structure by controlling the solubilisation process in situ. Instead of assembling separate layers, the variable pressure-temperature conditions create concentration gradients that result in seamless layered structures with gradual transitions, eliminating interface discontinuities and simplifying manufacturing.
Solution Approach 2:
The patent applies preliminary action by establishing the concentration gradient during the solubilisation step before foaming occurs. The non-uniform distribution of the foaming agent is created in advance through variable solubilisation conditions, ensuring that the subsequent foaming process naturally produces the desired layered structure without requiring post-processing assembly.
3Productivity
If pre-foamed beads are stored for extended periods, then production flexibility is improved, but foaming agent loss via diffusion increases
Solution Approach 1:
The patent applies local quality by creating a dense outer layer through variable solubilisation conditions that concentrate the foaming agent at the surfaces. This dense layer acts as a barrier that locally prevents diffusion, while the inner regions maintain their foaming capability. This spatially differentiated structure reduces overall foaming agent loss during storage.
Solution Approach 2:
The patent implements beforehand cushioning by creating a protective dense layer during the initial solubilisation process. This layer serves as a pre-established barrier that cushions against subsequent foaming agent diffusion during storage, preserving the beads' integrity and reducing losses over time.
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 process allows for the production of foamed polymers with specific, varying morphologies and densities across multiple layers, enhancing design flexibility and avoiding the use of composite materials, thus enabling the creation of complex, anisotropic structures with improved structural and functional properties.
Implementation Method 1
a step of solubilisation of at least one foaming agent in a polymer is carried out with a pressure profile of said at least one foaming agent that is variable over time
Implementation Method 2
the most remote portions (with respect to the free surfaces in contact with the foaming agent under pressure) of the samples to be foamed contain a lower concentration of the foaming agent with respect to the portions adjacent to said surfaces
Implementation Method 3
a step of foaming of the polymer is carried out... upon foaming, generate non-uniform profiles of the concentrations of the physical foaming agents in the polymer, which... generate correspondingly non-uniform morphologies and densities
Data Source
Figure 1A~1B
Figure 2A~2B
Figure 2C~3A
AI summary
The present invention concerns layered foamed polymeric materials lacking discontinuities at the interface between the layers and a preparation process thereof comprising the following steps: - providing a foamable polymeric material; - solubilising said one or more foaming agents in the foamable polymeric material under pressure and at a temperature greater than 20°C; and - releasing the pressure instantaneously; where the solubilisation step is carried out with a pressure profile of said one or more foaming agents that is variable over time.