Mechanical Reticulation of Closed-Cell Foams With Needle Arrays
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing chemical and thermal methods for reticulating polymeric-based closed cell foams are inefficient in controlling the amount of reticulation, making them unsuitable for biomedical applications.
Innovation Solution
A mechanical reticulation system using a device with a needle array and a shaker to oscillate needles into the foam, allowing controlled puncturing of membranes to regulate the amount of reticulation, preserving the structural integrity of the struts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If chemical etching is used to reticulate polymeric-based closed cell foams, then the membranes between pores are dissolved, but the control over the amount of reticulation is poor
Solution Approach 1:
The patent replaces chemical etching with a mechanical reticulation system consisting of a needle array and vibratory shaker. The mechanical needles physically puncture the foam membranes under vibration, providing precise control over reticulation extent while maintaining process simplicity. This substitution of chemical method with mechanical method resolves the contradiction between control precision and ease of manufacture.
Solution Approach 2:
The patent controls the reticulation process by adjusting parameters such as vibration amplitude, frequency, and needle penetration depth. By changing these physical parameters, precise control over the amount of reticulation is achieved, directly addressing the lack of control in chemical etching methods.
2Manufacturing precision
If thermal reticulation is used to burn the membranes, then the membranes are removed, but the structural integrity of the struts may be compromised
Solution Approach 1:
The patent replaces thermal reticulation with a mechanical needle-based system. The mechanical needles selectively puncture membranes without applying the high temperatures that could compromise strut integrity. This mechanical approach provides precise control over membrane removal while preserving the structural strength of the foam struts.
Solution Approach 2:
The needle array provides localized mechanical action that selectively targets membranes while leaving struts intact. The local mechanical puncturing action allows precise control over which membranes are removed without affecting the overall structural integrity of the foam framework.
3Manufacturing precision
If existing reticulation methods are used, then membranes are removed, but the shape memory behavior and mechanical properties are not preserved
Solution Approach 1:
The patent replaces chemical and thermal methods with a mechanical needle-based system that preserves the polymeric material's properties. The mechanical puncturing action removes membranes without introducing chemicals or heat that could alter the shape memory behavior, thereby maintaining both control precision and material reliability.
Solution Approach 2:
The mechanical reticulation system allows the foam material to retain its inherent shape memory properties by using a physical process that does not interfere with the polymer's molecular structure. The needles simply create physical openings without chemically or thermally modifying the material, enabling the foam to self-maintain its shape memory behavior.
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 mechanical method enables precise control over the reticulation process, maintaining the shape memory behavior and mechanical properties of the foam, suitable for biomedical applications such as vascular occlusion devices.
Implementation Method 1
a shaker, capable of receiving a sample of a polymeric-based closed cell foam, the array configured so that the plurality of needles puncture membranes of the sample of the polymeric-based closed cell foam in at least one axis due, at least in part, to an oscillation of the shaker
Implementation Method 2
the plurality of needles puncture membranes of the sample of the polymeric-based closed cell foam in at least one axis due, at least in part, to an oscillation of the shaker and a motion of the plurality of needles of the array into the sample of the polymeric-based closed cell foam
Data Source
AI summary
Polymeric based closed cell foams, such as shape memory polymer foams, contain bubbles. Making these bubbles continuous is called reticulation. Disclosed are embodiments of a device and method to controllably reticulate polymer-based closed cell foams by puncturing the membranes of these polymer-based closed cell foams.