Hollow Particle Shell Composition for High Void Ratio Strength
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hollow resin particles produced by existing methods are prone to collapse under shear or pressure during mixing or molding processes, and they retain significant amounts of volatile compounds like non-reactive hydrocarbon solvents and unreacted monomers, which can cause ignition or smoke.
Innovation Solution
A method involving suspension polymerization using a mixture liquid containing a polymerizable monomer, a polar resin, a sparingly water-soluble inorganic metal salt as a dispersant, and an aqueous medium to form droplets with controlled distribution, followed by polymerization and solvent removal, results in hollow particles with a high void ratio and reduced collapse risk and volatile compound residues.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Weight of moving object
If the void ratio of hollow particles is increased, then weight reduction and heat insulation properties are improved, but the shell thickness is decreased and the hollow particles easily collapse
Solution Approach 1:
The patent changes the chemical composition parameters of the shell material by incorporating specific functional monomers (hydroxyl-group-containing monomers, carboxyl-group-containing monomers, or amino-group-containing monomers) into the polymer shell. This chemical modification enhances the intermolecular forces and structural integrity of the shell, allowing it to maintain sufficient thickness while providing high collapse resistance even at high void ratios (50-90%).
Solution Approach 2:
The patent creates a composite shell structure by copolymerizing multiple types of monomers including vinyl monomers, crosslinkable monomers, and functional monomers containing hydroxyl, carboxyl, or amino groups. This composite approach combines the structural framework provided by the vinyl monomer shell with the enhanced mechanical strength and intermolecular bonding provided by the functional monomers, resulting in a shell that can sustain high void ratios without collapsing.
2Productivity
If conventional polymerization methods are used, then production efficiency is maintained, but residual volatile compounds such as hydrocarbon solvents and unreacted monomers remain in the hollow particles
Solution Approach 1:
The patent employs a two-phase polymerization system where the polymerization reaction occurs in an organic phase (hydrocarbon solvent) while being initiated by a water-soluble polymerization initiator from the aqueous phase. This phase transition approach allows complete polymerization of monomers in the organic phase, converting them from harmful unreacted monomers to stable polymer structures, while the phase separation facilitates removal of residual solvents and byproducts.
Solution Approach 2:
The patent replaces conventional mechanical mixing and processing methods with a chemically-driven polymerization system. By using water-soluble polymerization initiators that decompose thermally to generate radicals, the system achieves complete monomer conversion and shell formation without requiring extensive mechanical processing that could leave residual solvents. The chemical reaction pathway ensures thorough consumption of volatile compounds.
3Weight of moving object
If the shell thickness is decreased to achieve high void ratio, then weight reduction is improved, but the hollow particles cannot withstand shear or pressure during biaxial kneading or injection molding
Solution Approach 1:
The patent modifies the chemical parameters of the shell material by incorporating functional monomers with hydroxyl, carboxyl, or amino groups. These functional groups form strong intermolecular hydrogen bonds and dipole-dipole interactions, significantly enhancing the mechanical strength and elasticity of the shell. This allows the shell to maintain adequate thickness while providing the necessary reliability to withstand shear stresses during biaxial kneading and pressure during injection molding.
Solution Approach 2:
The patent creates a composite shell structure through copolymerization of vinyl monomers with crosslinkable monomers and functional monomers. The crosslinkable monomers form a three-dimensional crosslinked network within the shell matrix, while the functional monomers contribute additional intermolecular bonding. This composite structure provides exceptional mechanical strength and elasticity, enabling thin-walled hollow particles to reliably withstand the demanding processing conditions of biaxial kneading and injection molding.
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 method produces hollow particles with enhanced strength and reduced volatile content, minimizing collapse and safety hazards during processing, while maintaining a high void ratio for improved optical and thermal properties.
Implementation Method 1
a mixture liquid containing a polymerizable monomer for shell, a polar resin, a hydrocarbon solvent, and a sparingly water-soluble inorganic metal salt as a dispersant, followed by polymerization
Implementation Method 2
a hydrocarbon solvent removal step comprising removing the hydrocarbon solvent included in the hollow particles obtained by the polymerization step
Data Source
AI summary
The method produces hollow particles which have a high void ratio, which can reduce the residual amount of a sparingly water-soluble solvent used in the production process, and which are less likely to collapse. The method for producing hollow particles which comprise a shell and a hollow portion and which have a void ratio of 50% or more and 90% or less, wherein a suspension treatment of a mixture liquid containing a polymerizable monomer for shell, a polar resin, a hydrocarbon solvent, a sparingly water-soluble inorganic metal salt as a dispersant, and an aqueous medium is carried out to prepare a suspension in which droplets of a monomer composition containing the polymerizable monomer for shell, the polar resin and the hydrocarbon solvent are dispersed in the aqueous medium; a polymerization reaction of the suspension is carried out; and the hydrocarbon solvent is removed from the obtained hollow particles.