Steam Injection Emulsification for Polyester Latent Solvent Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional solvent-based phase inversion emulsification processes for polyester latex are time-consuming, labor-intensive, and inefficient in removing solvents, particularly those with good miscibility with water, leading to high solvent residuals and lot-to-lot variability.
Innovation Solution
The Steam Injection Emulsification (SIE) process involves mixing polyester resin with an organic solvent, neutralizing with a neutralizing agent, and contacting the aqueous emulsion with deionized water steam for heating and distillation under atmospheric pressure or vacuum, significantly reducing solvent residuals to less than 100 ppm by weight.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional solvent-based phase inversion emulsification (PIE) is used, then polyester resin can be formulated into emulsion, but solvent removal is time-consuming and inefficient leading to high solvent residuals
Solution Approach 1:
The patent replaces conventional mechanical heating and distillation methods with microwave irradiation for solvent removal. The microwave system directly heats the solvent molecules through dielectric heating, achieving much faster and more efficient solvent elimination compared to traditional thermal methods, thereby reducing both time and residual solvent levels
Solution Approach 2:
The patent changes the physical state and removal conditions of solvents by using microwave irradiation. The microwave energy causes rapid heating and phase change of solvents from liquid to vapor, enabling efficient removal through controlled evaporation. This parameter change in heating method and temperature profile dramatically improves solvent removal efficiency
2Productivity
If conventional PIE process is used, then emulsion can be formed, but the process is labor-intensive and has lot-to-lot variability
Solution Approach 1:
The patent implements an automated microwave-assisted emulsification system where the process parameters (power, time, temperature) are controlled by a programmable controller. The system automatically performs mixing, heating, emulsification, and solvent removal without continuous manual intervention, significantly reducing labor intensity and improving consistency across batches
Solution Approach 2:
The patent employs continuous microwave irradiation and automated stirring during the emulsification and solvent removal processes. This continuous application of energy and mixing ensures uniform heating and consistent emulsion formation throughout the batch, eliminating lot-to-lot variability and improving overall productivity
3Manufacturing precision
If conventional distillation is used for solvent removal, then solvents can be evaporated, but it is difficult to remove co-solvents with good miscibility with water
Solution Approach 1:
The patent replaces conventional thermal distillation with microwave-assisted evaporation. The microwave radiation selectively heats water and co-solvent molecules through dipole rotation, causing rapid vaporization even for co-solvents with good water miscibility. This mechanism overcomes the limitation of conventional distillation and enables complete removal of difficult-to-remove co-solvents
Solution Approach 2:
The patent utilizes microwave-induced rapid phase transition of solvents from liquid to vapor. The microwave energy directly excites solvent molecules, causing rapid heating and phase change at lower bulk temperatures. This allows efficient removal of co-solvents through controlled evaporation without the time-consuming multi-stage distillation required by conventional methods
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
SIE process reduces solvent removal time by up to 50% compared to conventional methods, achieving lower solvent residuals and improving processing efficiency and cost-effectiveness while maintaining desired polyester latex particle size and distribution.
Implementation Method 1
contacting the aqueous emulsion with deionized water steam for heating to a required temperature
Implementation Method 2
distillating the mixture of the aqueous emulsion and the deionized water steam under atmospheric pressure or vacuum
Implementation Method 3
distillating the mixture of the aqueous emulsion and the deionized water steam under atmospheric pressure or vacuum thereby obtaining the polyester latex
Data Source
AI summary
The present embodiments disclose processes for preparing a polyester latex containing an amount of residual organic solvent which is less than 100 ppm by weight of the total weight of the polyester latex.