The Tool Desk
Outbyte PC Repair FREERepair Windows errors before they cause bigger problemsFix Now →Outbyte Driver Updater FREEFix the driver behind crashes, sound loss and screen glitchesFind Drivers →iTechGuides is reader-supported. When you buy through links on our site, we may earn an affiliate commission. As an Amazon Associate I earn from qualifying purchases. Learn more
Phase Separation Micro Molding (PSμM) uses a patterned mold and a phase-separating polymer solution to make thin microfluidic films whose walls can be dense, porous beneath a dense skin, or porous throughout. The method’s key advantage is that pore structure and channel pattern can be formed together; the trade-off is that the result depends on the polymer chemistry and processing conditions, and porosity is limited by mechanical stability.
What is Phase Separation Micro Molding?
PSμM is a replication technique for forming thin polymer films with microchannel patterns and controllable porosity. In the 2005 study by J. de Jong, B. Ankoné, R. G. H. Lammertink, and M. Wessling at the University of Twente, researchers cast a polymer solution onto a microstructured mold, then immersed it in a non-solvent bath. Exchange between solvent and non-solvent induced phase separation and caused the polymer to precipitate into a patterned film. Slight shrinkage helped release the film from the mold. The authors sealed films to a transparent cover slip and also demonstrated stacked multilayer assemblies. The original study appeared in Lab on a Chip in 2005.
The study used PMMA and ABS copolymer as examples, with N-methyl-2-pyrrolidone or acetone as solvents and water or ethanol as non-solvents. Silicon wafers served as microstructured molds. These are materials in that historical experiment, not a current recipe, procurement recommendation, or safety protocol.
Quick wins for a faster PC:
Repair Windows errors before they cause bigger problemsFix Now →Scan for outdated or missing drivers - takes under a minuteDriver Scan →Clear out junk files and repair common Windows errorsFree Scan →How does phase separation create pores?
A polymer solution begins as a homogeneous mixture. It can be driven into a supersaturated state by evaporating solvent, changing temperature, or introducing a non-solvent. In nonsolvent-induced phase separation, the non-solvent mixes with the solvent but not with the polymer. As the liquids exchange, the solution separates into polymer-rich and polymer-lean regions. The polymer-rich phase gels and solidifies, while the polymer-lean regions become pores.
#1 Best Overall
- Standard matched fittings, perfect fit most common PDMS microfluidic chips set.
- Stable sealing performance, Practical integrated design, meet daily microscale fluid testing needs.
- Do not push samples into the chip manually. Under normal use, keep pressure ≤ 2 bar and maximum flow rate ≤ 2 ml/min. Exceeding these parameters will cause permanent damage to the chip.
In PSμM, the resulting structure depends on the polymer/solvent/non-solvent system, temperature, casting thickness, and pretreatment before immersion. Pretreatment can include partial solvent evaporation or exposure to non-solvent vapor. Changing these conditions can produce several different wall structures rather than one fixed type.
What pore structures can PSμM make?
| Structure | What it means | Transport implication |
|---|---|---|
| Dense film | No porous structure is formed in the film. | Does not provide the open-pore pathways of a porous wall. |
| Porous body with a dense skin | A porous substructure lies beneath a nonporous surface layer. | The dense skin can support gas or vapor transport and related operations while acting as a barrier to bulk flow. |
| Fully porous film | Pores extend through the film rather than being covered by a dense skin. | Can permit broader mass transport through the channel wall. |
The 2005 paper describes pore sizes from zero to several microns and notes that mechanical stability, not the process alone, limits the maximum achievable porosity. The size and openness of pores therefore have to be considered alongside the strength the film must retain.
Rank #2
- Replacement accessory kit for microfluidic chips includes PTFE tubing, blunt needles, needle tips, syringes and syringe filters in one package
- PTFE tubing 0.7 meter, ID 0.5mm, OD 1.0mm, fits standard 22G microfluidic fittings and 0.7mm chip inlet and outlet ports
- Six 22G stainless steel blunt needles and three needle tips connect syringes to tubing with luer-lock fittings for secure fluid delivery
- Three 2mL luer-lock syringes and three 0.22 micrometer PES syringe filters for sample loading and filtration before chip injection
- Works with LabCore Materials microfluidic chips and other standard PDMS or glass microfluidic devices for research use only
What did the 2005 study demonstrate?
The proof of concept was fast CO₂ transport through channel walls in a porous multilayer chip. The authors also reported enhanced gas permeation when chip thickness was reduced and porosity was incorporated, comparing porous films with dense films made from the same material and with PDMS. Those are laboratory results from the study’s particular materials and conditions, not a general performance guarantee for every PSμM device.
The article’s experimental setup included channel widths of 100 μm and mold rim heights of 50 μm. It also discusses process features down to 150 nm. These are specifications from the reported experiment and process discussion, not general performance statistics or a promise that every mold and material combination will reproduce those dimensions.
Rank #3
- Standard matched fittings, perfect fit most common PDMS microfluidic chips set.
- Stable sealing performance, Practical integrated design, meet daily microscale fluid testing needs.
- Do not push samples into the chip manually. Under normal use, keep pressure ≤ 2 bar and maximum flow rate ≤ 2 ml/min. Exceeding these parameters will cause permanent damage to the chip.
What can porous microfluidic walls be used for?
A porous wall can provide a controlled path for transport between a microchannel and its surroundings, or between channels in an assembly. The original authors proposed applications including:
- Gas–liquid or liquid–liquid contacting
- Membrane emulsification
- Separation or concentration of solutes, particles, or cells
- Degassing and pervaporation
- Concentration by evaporation
These are proposed uses, not all demonstrated outcomes. The specific demonstration was CO₂ transport through porous channel walls. Fully porous films are suited to broader mass transport, while a porous structure with a dense skin is described for gas and vapor transport and related operations. The needed morphology depends on what should cross the wall and what should remain contained.
Rank #4
- Double herringbone microchannel design enhances passive fluid mixing efficiency under laminar flow conditions, supporting stable and repeatable laboratory experiments.
- PDMS microfluidic chip features high optical transparency and flexible sealing performance, making it suitable for microscopy observation and laboratory research.
- Compatible with syringe pumps, laboratory tubing systems and common microfluidic accessories for fluid handling, chip testing and experimental development.
- Suitable for microfluidic research, liposome preparation, nanoparticle studies, laboratory demonstrations and academic research applications.
Why does mold geometry matter?
“Tunable” does not mean a recipe will produce the same surface pores on every pattern. A 2020 Polymer Journal study on micropatterned polyethersulfone (PES) membranes found that the patterned substrate significantly changed surface porosity and could lead to macrovoids under conditions that behaved differently on a flat substrate. The researchers used vapor-induced phase separation before nonsolvent-induced phase separation to prevent macrovoid formation, then adjusted casting-solution composition to obtain open pores. The PES study shows why mold geometry and the sequence of processing steps must be considered when targeting a particular surface morphology.
What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
How does PSμM compare with other chip fabrication approaches?
PSμM’s distinctive feature is combining pattern replication with control over porosity in a thin film. The 2005 authors presented it as an alternative to approaches such as etching and hot embossing, but the evidence described is a laboratory proof of concept, not a broad head-to-head evaluation across materials, device designs, or production settings.
Best Value
- The Fast Chip SMD Removal Kit is a quick and inexpensive way to remove SMD components from a PCB without a hot air station using only your soldering iron.
- Removes QFP's, PLCC's, SOIC's, and chip components under 300 degrees Fahrenheit
- Enough material to remove 8-10 SMD'S
- The Kit Contains: 2.7 ft. Fast Chip Removal Alloy - 1 2cc tube of SRA TF5000 No Clean Rework Paste Flux and complete Instructions for SMD Removal and Cleanup
- Lead Free
For a device decision, the relevant question is not simply which fabrication method is best. It is whether the chosen process can deliver the required channel pattern and wall structure while retaining enough mechanical stability. Gas permeation, selectivity, film thickness, flexibility, material compatibility, and the desired transport operation all matter. The study’s comparison with dense films and PDMS concerns gas permeation under its experimental conditions; it does not establish PSμM as a universal replacement for either option.
What could multilayer chips make possible?
The authors suggested stacking films with different morphologies to combine multiple operations in one assembly. They also identified disposable chips and scale-out as possibilities. Those are proposed directions, not evidence of industrial-scale production or established commercial and clinical readiness.
Quick Recap
Sources
- J. de Jong et al., “New replication technique for the fabrication of thin polymeric microfluidic devices with tunable porosity,” Lab on a Chip, first published 28 September 2005: https://doi.org/10.1039/B510261K.
- Bea Perks, “Phase separation produces porous chips,” Chemistry World, 9 November 2005: https://www.chemistryworld.com/news/phase-separation-produces-porous-chips/3001641.article.
- Yida Liu et al., “Fine-tuning of the surface porosity of micropatterned polyethersulfone membranes prepared by phase separation micromolding,” Polymer Journal, volume 52, pages 397–403 (2020): https://doi.org/10.1038/s41428-019-0265-6.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
Recommended Free Tools
