Removable Silicone Films via Reversible Crosslinking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for removing inks and adhesives from plastic packaging for recycling often require toxic chemicals and high temperatures, which are unsuitable for certain substrate materials and pose environmental and health concerns, and existing removable polymer adhesives still rely on chemicals and high temperatures.
Innovation Solution
Reversibly crosslinkable compositions comprising entangled polysiloxane chains with pendant functional groups and inorganic oxide nanoparticles that form non-covalent bonds, allowing for the formation of a polymeric matrix that can be collapsed using mild conditions such as water and low temperatures, enabling the removal of the adhesive without harsh chemicals or high temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If toxic chemicals and high temperatures are used to remove inks and adhesives from plastic packaging, then removal effectiveness is improved, but health and environmental safety deteriorates
Solution Approach 1:
The invention changes the parameters of the removal process by using mild temperatures (below 100°C) and water-based solutions instead of high temperatures and toxic chemicals, achieving effective adhesive removal while eliminating harmful effects on health and environment
Solution Approach 2:
The invention converts the normally harmful effect of water (which can cause adhesive failure) into a beneficial removal mechanism by using controlled water exposure at mild temperatures to trigger reversible dissociation of the adhesive from the substrate
2Reliability
If high temperatures are used to remove adhesives, then removal effectiveness is improved, but substrate material integrity deteriorates
Solution Approach 1:
The invention changes the temperature parameter from high temperatures (typically >100°C) to mild temperatures (below 100°C), effectively removing adhesives while preserving the integrity of temperature-sensitive substrate materials
3Reliability
If expensive chemical components are used in removable materials and release liners, then adhesive performance is improved, but manufacturing cost increases
Solution Approach 1:
The invention enables the adhesive to self-release through controlled water exposure and mild heating, eliminating the need for expensive chemical release agents and complex release liner structures, thereby reducing manufacturing costs while maintaining adhesive performance
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 allows for the efficient and environmentally friendly removal of adhesives from substrates using mild conditions, reducing health and environmental risks while maintaining the mechanical properties of the crosslinked films, making the process suitable for various substrate materials.
Implementation Method 1
non-covalent bonds between the pendant functional groups and the inorganic oxide nanoparticles crosslink the entangled chains to form a polymeric matrix
Implementation Method 2
the non-covalent bonds dissociate and the polymeric matrix collapses in the presence of water and heat
Data Source
AI summary
Reversibly crosslinkable compositions are provided for forming removable crosslinked films. A reversibly crosslinkable composition may comprise entangled chains of a polysiloxane comprising pendant functional groups having formula —NH—(C═O)—X—COOH, wherein X is an alkyl group, an alkenyl group, or an aryl group; a plurality of inorganic oxide nanoparticles; and a solvent; wherein non-covalent bonds between the pendant functional groups and the inorganic oxide nanoparticles crosslink the entangled chains to form a polymeric matrix in the absence of the solvent, wherein the non-covalent bonds dissociate and the polymeric matrix collapses in the presence of water and heat.