Hydrogel Coating Adhesion to Polymeric Substrates
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing hydrogel compositions used in wound care often lack robust adhesion to polymeric substrates, leading to diminished adhesion when exposed to wound exudate, which can hinder their effectiveness in maintaining a suitable moisture balance for healing.
Innovation Solution
A method involving a polymeric substrate with an abstractable hydrogen atom, coated with a Type II photoinitiator and an aqueous composition containing hydrophilic monomers, water-swellable clay, and a water-soluble photoinitiator, followed by curing, to form a hydrogel coating covalently bonded to the substrate, ensuring durable attachment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If adhesive is used to attach hydrogel to polymeric substrate, then initial adhesion is achieved, but adhesion is lost when hydrogel absorbs water
Solution Approach 1:
The patent applies a silane coupling agent to the polymeric substrate before applying the hydrogel. This preliminary action creates covalent bonding sites on the substrate surface that will form permanent bonds with the hydrogel network, ensuring adhesion is maintained even when the hydrogel absorbs water and changes its physical state.
Solution Approach 2:
The silane coupling agent acts as an intermediary between the polymeric substrate and the hydrogel. It forms a chemical bridge that connects the substrate to the hydrogel network, providing a stable bonding interface that is not affected by the hydrogel's water absorption and swelling.
2Stability of the object's composition
If covalent crosslinking is used to maintain hydrogel shape, then structural stability is improved, but adhesion to substrate is reduced
Solution Approach 1:
The patent segments the bonding function into two distinct parts: covalent crosslinking within the hydrogel network for structural stability, and separate silane coupling at the substrate interface for adhesion. This segmentation allows each function to be optimized independently without compromising the other.
Solution Approach 2:
The patent applies different chemical properties to different regions: the bulk hydrogel contains crosslinking groups for shape stability, while the interface region contains silane coupling agents for adhesion. This local differentiation of chemical functionality resolves the contradiction between structural stability and adhesion.
3Ease of operation
If hydrogel absorbs wound exudate, then wound moisture management is improved, but adhesion to backing layer is diminished
Solution Approach 1:
The silane coupling agent is applied to the substrate before the hydrogel, creating a permanent chemical bond interface. This preliminary action ensures that adhesion is established before any water absorption occurs, so the hydrogel can freely absorb wound exudate without losing attachment to the backing layer.
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 solution provides a hydrogel coating with enhanced adhesion to polymeric substrates, maintaining attachment even after absorbing exudate, thus effectively managing wound moisture and promoting healing.
Implementation Method 1
coating the polymeric substrate with a Type II photoinitiator
Implementation Method 2
2-20 % wt water-swellable clay
Implementation Method 3
curing the aqueous coated substrate
Data Source
AI summary
Described herein is a hydrogel-containing multilayer article and methods of making, said hydrogel-containing multilayer article comprising: (i) a polymeric substrate comprising an abstractable atom; and (ii) a cured aqueous coating composition thereon wherein the coating composition comprises: (a) a hydrophilic monomer comprising a (meth)acrylamide, (meth)acrylate, and combinations thereof: (b) at least 2 wt% of a water-swellable clay; (c) a water-soluble type I photoinitiator; and (d) an acid or salt wherein a water insoluble type II photoinitiator is localized at the interface between the hydrogel coating and the polymeric substrate.