Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
6.6
5.0
Journals
Polymers
Special Issues
Polymer Micro/Nanofabrication and Manufacturing
share announcement

Polymer Micro/Nanofabrication and Manufacturing

A special issue of Polymers (ISSN 2073-4360). This special issue belongs to the section "Polymer Processing and Engineering".

Deadline for manuscript submissions: closed (28 May 2022) | Viewed by 41100

Special Issue Editor

Prof. Dr. Yi-Je Juang

E-Mail Website1 Website2
Guest Editor
Department of Chemical Engineering, National Cheng Kung University, Tainan 717005, Taiwan
Interests: micro/nanofabrication; polymer microembossing; microfluidics; BioMEMS
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

In the field of microfabrication, the utilization of polymers as the substrate material has compelling advantages over other materials owing to their versatile properties, such as low protein adsorption, biocompatibility, surface functionality/modification, mechanical strength, chemical resistance, and low electrical and thermal conductivities. Moreover, the mass production capability of polymeric materials makes it possible to manufacture low-cost products such that they become affordable for one-time use, which is necessary in clinical diagnostics and many biomedical applications. The global market size for emerging gadgets like microfluidic devices and BioMEMS is estimated to be around $15 billion by 2025, wherein the polymer segment accounts for a significant share. Therefore, the aim of this Special Issue is to collect ongoing scientific research on and developments in polymer microfabrication and manufacturing for its potential application in every field of interest. Research as well as review articles are welcome.

Prof. Dr. Yi-Je Juang
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Polymers is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • microfabrication
  • polymer
  • elastomer
  • micro-embossing
  • imprinting
  • micro-injection molding
  • resin transfer molding
  • roll-to-roll
  • roll-to-plate
  • mold making
  • numerical simulation
  • modeling
  • rheological properties of polymers
  • novel technique
  • manufacturing

Related Special Issue

Published Papers (16 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Editorial

Jump to: Research, Review

2 pages, 168 KiB  
Editorial
Polymer Micro/Nanofabrication and Manufacturing
by Yi-Je Juang
Polymers 2023, 15(6), 1350; https://doi.org/10.3390/polym15061350 - 8 Mar 2023
Cited by 1 | Viewed by 1080
Abstract
Polymer microfabrication/nanofabrication and manufacturing are processes that involve the creation of small-scale structures using various polymeric materials [...] Full article
(This article belongs to the Special Issue Polymer Micro/Nanofabrication and Manufacturing)

Research

Jump to: Editorial, Review

20 pages, 6814 KiB  
Article
An Effective Shrinkage Control Method for Tooth Profile Accuracy Improvement of Micro-Injection-Molded Small-Module Plastic Gears
by Wangqing Wu, Xiansong He, Binbin Li and Zhiying Shan
Polymers 2022, 14(15), 3114; https://doi.org/10.3390/polym14153114 - 30 Jul 2022
Cited by 8 | Viewed by 2058
Abstract
An effective method to control the non-linear shrinkage of micro-injection molded small-module plastic gears by combining multi-objective optimization with Moldflow simulation is proposed. The accuracy of the simulation model was verified in a micro-injection molding experiment using reference process parameters. The maximum shrinkage [...] Read more.
An effective method to control the non-linear shrinkage of micro-injection molded small-module plastic gears by combining multi-objective optimization with Moldflow simulation is proposed. The accuracy of the simulation model was verified in a micro-injection molding experiment using reference process parameters. The maximum shrinkage (Y1), volume shrinkage (Y2), addendum diameter shrinkage (Y3), and root circle diameter shrinkage (Y4) were utilized as optimization objectives to characterize the non-linear shrinkage of the studied gear. An analysis of the relationship between key process parameters and the optimization objectives was undertaken using a second-order response surface model (RSM-Quadratic). Finally, multi-objective optimization was carried out using the non-dominated sorting genetic algorithm-II (NSGA-II). The error rates for the key shrinkage dimensions were all below 2%. The simulation results showed that the gear shrinkage variables, Y1, Y2, Y3, and Y4, were reduced by 5.60%, 8.23%, 11.71%, and 11.39%, respectively. Moreover, the tooth profile inclination deviation (fHαT), the profile deviation (ffαT), and the total tooth profile deviation (FαT) were reduced by 47.57%, 23.43%, and 49.96%, respectively. Consequently, the proposed method has considerable potential for application in the high-precision and high-efficiency manufacture of small-module plastic gears. Full article
(This article belongs to the Special Issue Polymer Micro/Nanofabrication and Manufacturing)
►▼ Show Figures

Graphical abstract

12 pages, 5659 KiB  
Article
Numerical Simulation on the Acoustic Streaming Driven Mixing in Ultrasonic Plasticizing of Thermoplastic Polymers
by Wangqing Wu, Yang Zou, Guomeng Wei and Bingyan Jiang
Polymers 2022, 14(6), 1073; https://doi.org/10.3390/polym14061073 - 8 Mar 2022
Cited by 3 | Viewed by 1387
Abstract
The acoustic melt stream velocity field, total force, and trajectory of fluorescent particles in the plasticizing chamber were analyzed using finite element simulation to investigate the acoustic streaming and mixing characteristics in ultrasonic plasticization micro-injection molding (UPMIM). The fluorescence intensity of ultrasonic plasticized [...] Read more.
The acoustic melt stream velocity field, total force, and trajectory of fluorescent particles in the plasticizing chamber were analyzed using finite element simulation to investigate the acoustic streaming and mixing characteristics in ultrasonic plasticization micro-injection molding (UPMIM). The fluorescence intensity of ultrasonic plasticized samples containing thermoplastic polymer powders and fluorescent particles was used to determine the correlation between UPMIM process parameters and melt mixing characteristics. The results confirm that the acoustic streaming driven mixing occurs in ultrasonic plasticization and could provide similar shear stirring performance as the screw in traditional extrusion/injection molding. It was found that ultrasonic vibrations can cause several melt vortices to develop in the plasticizing chamber, with the melt rotating around the center of the vortex. With increasing ultrasonic amplitude, the melt stream velocity was shown to increase while retaining the trace, which could be altered by modulating other parameters. The fluorescent particles are subjected to a two-order-of-magnitude stronger Stokes drag force than the acoustic radiation force. The average fluorescence intensity was found to be adversely related to the distance from the sonotrodes’ end surface, and fluorescence particles were more equally distributed at higher parameter levels. Full article
(This article belongs to the Special Issue Polymer Micro/Nanofabrication and Manufacturing)
►▼ Show Figures

Figure 1

11 pages, 6669 KiB  
Article
Advanced Manufacturing in the Fabrication of a Lifelike Brain Glioblastoma Simulator for the Training of Neurosurgeons
by Pin-Chuan Chen, Yu-Wen Yang, Jang-Chun Lin and Wei-Hsiu Liu
Polymers 2022, 14(6), 1072; https://doi.org/10.3390/polym14061072 - 8 Mar 2022
Cited by 2 | Viewed by 1793
Abstract
Neurosurgeons require considerable expertise and practical experience to deal with the critical situations commonly encountered in complex surgical operations such as cerebral cancer; however, trainees in neurosurgery seldom have the opportunity to develop these skills in the operating room. Physical simulators can give [...] Read more.
Neurosurgeons require considerable expertise and practical experience to deal with the critical situations commonly encountered in complex surgical operations such as cerebral cancer; however, trainees in neurosurgery seldom have the opportunity to develop these skills in the operating room. Physical simulators can give trainees the experience they require. In this study, we adopted advanced molding and replication techniques in the fabrication of a physical simulator for use in practicing the removal of cerebral tumors. Our combination of additive manufacturing and molding technology with elastic material casting made it possible to create a simulator that realistically mimics the skull, brain stem, soft brain lobes, and cerebral cancer with cerebral tumors located precisely where they are likely to appear. Multiple and systematic experiments were conducted to prove that the elastic material used herein was appropriated for building professional medical physical simulator. One neurosurgical trainee reported that under the guidance of a senior neurosurgeon, the physical simulator helped to elucidate the overall process of cerebral cancer removal and provided a realistic impression of the tactile feelings involved in craniotomy. The trainee also learned how to make decisions when facing the infiltration of a cerebral tumor into normal brain lobes. Our results demonstrate the efficacy of the proposed physical simulator in preparing trainees for the rigors involved in performing highly delicate surgical operations. Full article
(This article belongs to the Special Issue Polymer Micro/Nanofabrication and Manufacturing)
►▼ Show Figures

Graphical abstract

11 pages, 3761 KiB  
Article
Fabrication of Paper-Based Microfluidics by Spray on Printed Paper
by Yi-Je Juang and Shu-Kai Hsu
Polymers 2022, 14(3), 639; https://doi.org/10.3390/polym14030639 - 8 Feb 2022
Cited by 6 | Viewed by 2231
Abstract
Since the monumental work conducted by Whitesides et al. in 2007, research and development of paper-based microfluidics has been widely carried out, with its applications ranging from chemical and biological detection and analysis, to environmental monitoring and food-safety inspection. Paper-based microfluidics possesses several [...] Read more.
Since the monumental work conducted by Whitesides et al. in 2007, research and development of paper-based microfluidics has been widely carried out, with its applications ranging from chemical and biological detection and analysis, to environmental monitoring and food-safety inspection. Paper-based microfluidics possesses several competitive advantages over other substrate materials, such as being simple, inexpensive, power-free for fluid transport, lightweight, biodegradable, biocompatible, good for colorimetric tests, flammable for easy disposal of used paper-based diagnostic devices by incineration, and being chemically modifiable. Myriad methods have been demonstrated to fabricate paper-based microfluidics, such as solid wax printing, cutting, photolithography, microembossing, etc. In this study, fabrication of paper-based microfluidics was demonstrated by spray on the printed paper. Different from the normally used filter papers, printing paper, which is much more accessible and cheaper, was utilized as the substrate material. The toner was intended to serve as the mask and the patterned hydrophobic barrier was formed after spray and heating. The processing parameters such as toner coverage on the printing paper, properties of the hydrophobic spray, surface properties of the paper, and curing temperature and time were systematically investigated. It was found that, after repetitive printing four times, the toner was able to prevent the hydrophobic spray (the mixture of PDMS and ethyl acetate) from wicking through the printing paper. The overall processing time for fabrication of paper-based microfluidic chips was less than 10 min and the technique is potentially scalable. Glucose detection was conducted using the microfluidic paper-based analytical devices (µPADs) as fabricated and a linear relationship was obtained between 1 and 10 mM. Full article
(This article belongs to the Special Issue Polymer Micro/Nanofabrication and Manufacturing)
►▼ Show Figures

Graphical abstract

10 pages, 3376 KiB  
Article
Using Stereolithographic Printing to Manufacture Monolithic Microfluidic Devices with an Extremely High Aspect Ratio
by Pin-Chuan Chen, Po-Tsang Chen and Tuan Ngoc Anh Vo
Polymers 2021, 13(21), 3750; https://doi.org/10.3390/polym13213750 - 29 Oct 2021
Cited by 2 | Viewed by 1659
Abstract
Stereolithographic printing (SL) is widely used to create mini/microfluidic devices; however, the formation of microchannels smaller than 500 μm with good inner surface quality is still challenging due to the printing resolution of current commercial printers and the z-overcure error and scalloping phenomena. [...] Read more.
Stereolithographic printing (SL) is widely used to create mini/microfluidic devices; however, the formation of microchannels smaller than 500 μm with good inner surface quality is still challenging due to the printing resolution of current commercial printers and the z-overcure error and scalloping phenomena. In the current study, we used SL printing to create microchannels with the aim of achieving a high degree of dimensional precision and a high-quality microchannel inner surface. Extensive experiments were performed and our results revealed the following: (1) the SL printing of microchannels can be implemented in three steps including channel layer printing, an oxygen inhibition process, and roof layer printing; (2) printing thickness should be reduced to minimize the scalloping phenomenon, which significantly improves dimensional accuracy and the quality of inner microchannel surfaces; (3) the inclusion of an oxygen inhibition step is a critical and efficient approach to suppressing the z-overcure error in order to eliminate the formation of in-channel obstructions; (4) microchannels with an extremely high aspect ratio of 40:1 (4000 μm in height and 100 μm in width) can be successfully manufactured within one hour by following the three-step printing process. Full article
(This article belongs to the Special Issue Polymer Micro/Nanofabrication and Manufacturing)
►▼ Show Figures

Graphical abstract

12 pages, 2653 KiB  
Article
Mechanical and Compositional Implications of Gallium Ion Milling on Epoxy Resin
by Raz Samira, Atzmon Vakahi, Rami Eliasy, Dov Sherman and Noa Lachman
Polymers 2021, 13(16), 2640; https://doi.org/10.3390/polym13162640 - 8 Aug 2021
Cited by 6 | Viewed by 2516
Abstract
Focused Ion Beam (FIB) is one of the most common methods for nanodevice fabrication. However, its implications on mechanical properties of polymers have only been speculated. In the current study, we demonstrated flexural bending of FIB-milled epoxy nanobeam, examined in situ under a [...] Read more.
Focused Ion Beam (FIB) is one of the most common methods for nanodevice fabrication. However, its implications on mechanical properties of polymers have only been speculated. In the current study, we demonstrated flexural bending of FIB-milled epoxy nanobeam, examined in situ under a transmission electron microscope (TEM). Controllable displacement was applied, while real-time TEM videos were gathered to produce morphological data. EDS and EELS were used to characterize the compositions of the resultant structure, and a computational model was used, together with the quantitative results of the in situ bending, to mechanically characterize the effect of Ga+ ions irradiation. The damaged layer was measured at 30 nm, with high content of gallium (40%). Examination of the fracture revealed crack propagation within the elastic region and rapid crack growth up to fracture, attesting to enhanced brittleness. Importantly, the nanoscale epoxy exhibited a robust increase in flexural strength, associated with chemical tempering and ion-induced peening effects, stiffening the outer surface. Young’s modulus of the stiffened layer was calculated via the finite element analysis (FEA) simulation, according to the measurement of 30 nm thickness in the STEM and resulted in a modulus range of 30–100 GPa. The current findings, now established in direct measurements, pave the way to improved applications of polymers in nanoscale devices to include soft materials, such as polymer-based composites and biological samples. Full article
(This article belongs to the Special Issue Polymer Micro/Nanofabrication and Manufacturing)
►▼ Show Figures

Graphical abstract

16 pages, 7396 KiB  
Article
Experimental Investigation of the Rapid Fabrication of Micron and Submicron Structures on Polymers Utilizing Ultrasonic Assisted Embossing
by Yongyong Zhu, Sebastian Bengsch, Lei Zheng, Yangyang Long, Bernhard Wilhelm Roth, Marc Christopher Wurz, Jens Twiefel and Jörg Wallaschek
Polymers 2021, 13(15), 2417; https://doi.org/10.3390/polym13152417 - 23 Jul 2021
Cited by 4 | Viewed by 1909
Abstract
Small-scale optical components with micron or submicron features have grown in popularity in recent years. High-quality, high-efficient, and cost-effective processing approaches for polymer optics mass production are an urgent need. In this study, ultrasonic vibration will be introduced in embossing. The major advantage [...] Read more.
Small-scale optical components with micron or submicron features have grown in popularity in recent years. High-quality, high-efficient, and cost-effective processing approaches for polymer optics mass production are an urgent need. In this study, ultrasonic vibration will be introduced in embossing. The major advantage is that the required energy can be provided for process times ranging from a few hundred milliseconds to a few seconds, and that the process energy is provided at exactly the required location so that the structures in the surrounding area are not affected. Due to the strong correlation between electrical impedance and the temperature of the material, a novel impedance-based control strategy has been utilized for precisely controlling ultrasonic vibration during the embossing process. The investigation used two types of stamps with grating line widths of 4 µm and 500 nm, respectively. As a result, an embossing time of less than a few seconds was accomplished and a uniform embossed surface with an average fill rate of more than 75% could be achieved. Full article
(This article belongs to the Special Issue Polymer Micro/Nanofabrication and Manufacturing)
►▼ Show Figures

Graphical abstract

9 pages, 7288 KiB  
Article
Fabrication of Oblique Submicron-Scale Structures Using Synchrotron Hard X-ray Lithography
by Kanghyun Kim, Kyungjin Park, Hyoryung Nam, Geon Hwee Kim, Seong Kyung Hong, Suhyeon Kim, Hyeonsu Woo, Seungbin Yoon, Jong Hyun Kim and Geunbae Lim
Polymers 2021, 13(7), 1045; https://doi.org/10.3390/polym13071045 - 26 Mar 2021
Cited by 3 | Viewed by 2073
Abstract
Oblique submicron-scale structures are used in various aspects of research, such as the directional characteristics of dry adhesives and wettability. Although deposition, etching, and lithography techniques are applied to fabricate oblique submicron-scale structures, these approaches have the problem of the controllability or throughput [...] Read more.
Oblique submicron-scale structures are used in various aspects of research, such as the directional characteristics of dry adhesives and wettability. Although deposition, etching, and lithography techniques are applied to fabricate oblique submicron-scale structures, these approaches have the problem of the controllability or throughput of the structures. Here, we propose a simple X-ray-lithography method, which can control the oblique angle of submicron-scale structures with areas on the centimeter scale. An X-ray mask was fabricated by gold film deposition on slanted structures. Using this mask, oblique ZEP520A photoresist structures with slopes of 20° and 10° and widths of 510 nm and 345 nm were fabricated by oblique X-ray exposure, and the possibility of polydimethylsiloxane (PDMS) molding was also confirmed. In addition, through double exposure with submicron- and micron-scale X-ray masks, dotted-line patterns were produced as an example of multiscale patterning. Full article
(This article belongs to the Special Issue Polymer Micro/Nanofabrication and Manufacturing)
►▼ Show Figures

Graphical abstract

17 pages, 2860 KiB  
Article
Cationic Cellulose Nanocrystals-Based Nanocomposite Hydrogels: Achieving 3D Printable Capacitive Sensors with High Transparency and Mechanical Strength
by Po-Cheng Lai and Sheng-Sheng Yu
Polymers 2021, 13(5), 688; https://doi.org/10.3390/polym13050688 - 25 Feb 2021
Cited by 32 | Viewed by 4198
Abstract
Hydrogel ionotronics are intriguing soft materials that have been applied in wearable electronics and artificial muscles. These applications often require the hydrogels to be tough, transparent, and 3D printable. Renewable materials like cellulose nanocrystals (CNCs) with tunable surface chemistry provide a means to [...] Read more.
Hydrogel ionotronics are intriguing soft materials that have been applied in wearable electronics and artificial muscles. These applications often require the hydrogels to be tough, transparent, and 3D printable. Renewable materials like cellulose nanocrystals (CNCs) with tunable surface chemistry provide a means to prepare tough nanocomposite hydrogels. Here, we designed ink for 3D printable sensors with cationic cellulose nanocrystals (CCNCs) and zwitterionic hydrogels. CCNCs were first dispersed in an aqueous solution of monomers to prepare the ink with a reversible physical network. Subsequent photopolymerization and the introduction of Al3+ ion led to strong hydrogels with multiple physical cross-links. When compared to the hydrogels using conventional CNCs, CCNCs formed a stronger physical network in water that greatly reduced the concentration of nanocrystals needed for reinforcing and 3D printing. In addition, the low concentration of nanofillers enhanced the transparency of the hydrogels for wearable electronics. We then assembled the CCNC-reinforced nanocomposite hydrogels with stretchable dielectrics into capacitive sensors for the monitoring of various human activities. 3D printing further enabled a facile design of tactile sensors with enhanced sensitivity. By harnessing the surface chemistry of the nanocrystals, our nanocomposite hydrogels simultaneously achieved good mechanical strength, high transparency, and 3D printability. Full article
(This article belongs to the Special Issue Polymer Micro/Nanofabrication and Manufacturing)
►▼ Show Figures

Graphical abstract

9 pages, 2904 KiB  
Communication
Micromechanical Punching: A Versatile Method for Non-Spherical Microparticle Fabrication
by Ritika Singh Petersen, Anja Boisen and Stephan Sylvest Keller
Polymers 2021, 13(1), 83; https://doi.org/10.3390/polym13010083 - 28 Dec 2020
Cited by 10 | Viewed by 2982
Abstract
Microparticles are ubiquitous in applications ranging from electronics and drug delivery to cosmetics and food. Conventionally, non-spherical microparticles in various materials with specific shapes, sizes, and physicochemical properties have been fabricated using cleanroom-free lithography techniques such as soft lithography and its high-resolution version [...] Read more.
Microparticles are ubiquitous in applications ranging from electronics and drug delivery to cosmetics and food. Conventionally, non-spherical microparticles in various materials with specific shapes, sizes, and physicochemical properties have been fabricated using cleanroom-free lithography techniques such as soft lithography and its high-resolution version particle replication in non-wetting template (PRINT). These methods process the particle material in its liquid/semi-liquid state by deformable molds, limiting the materials from which the particles and the molds can be fabricated. In this study, the microparticle material is exploited as a sheet placed on a deformable substrate, punched by a robust mold. Drawing inspiration from the macro-manufacturing technique of punching metallic sheets, Micromechanical Punching (MMP) is a high-throughput technique for fabrication of non-spherical microparticles. MMP allows production of microparticles from prepatterned, porous, and fibrous films, constituting thermoplastics and thermosetting polymers. As an illustration of application of MMP in drug delivery, flat, microdisk-shaped Furosemide embedded poly(lactic-co-glycolic acid) microparticles are fabricated and Furosemide release is observed. Thus, it is shown in the paper that Micromechanical punching has potential to make micro/nanofabrication more accessible to the research and industrial communities active in applications that require engineered particles. Full article
(This article belongs to the Special Issue Polymer Micro/Nanofabrication and Manufacturing)
►▼ Show Figures

Graphical abstract

9 pages, 2794 KiB  
Article
Electrostatic Self-Assembly of Composite Nanofiber Yarn
by Wei-Chih Wang, Yen-Tse Cheng and Benjamin Estroff
Polymers 2021, 13(1), 12; https://doi.org/10.3390/polym13010012 - 22 Dec 2020
Cited by 27 | Viewed by 3558
Abstract
Electrospinning polymer fibers is a well-understood process primarily resulting in random mats or single strands. More recent systems and methods have produced nanofiber yarns (NFY) for ease of use in textiles. This paper presents a method of NFY manufacture using a simplified dry [...] Read more.
Electrospinning polymer fibers is a well-understood process primarily resulting in random mats or single strands. More recent systems and methods have produced nanofiber yarns (NFY) for ease of use in textiles. This paper presents a method of NFY manufacture using a simplified dry electrospinning system to produce self-assembling functional NFY capable of conducting electrical charge. The polymer is a mixture of cellulose nanocrystals (CNC), polyvinyl acrylate (PVA) and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS). When treated with ethylene glycol (EG) to enhance conductivity, fibers touching the collector plate align to the applied electrostatic field and grow by twisting additional nanofiber polymers injected by the jet into the NFY bundle. The longer the electrospinning continues, the longer and more uniformly twisted the NFY becomes. This process has the added benefit of reducing the electric field required for NFY production from >2.43 kV cm−1 to 1.875 kV cm−1. Full article
(This article belongs to the Special Issue Polymer Micro/Nanofabrication and Manufacturing)
►▼ Show Figures

Graphical abstract

14 pages, 6659 KiB  
Article
Engineering Additive Manufacturing and Molding Techniques to Create Lifelike Willis’ Circle Simulators with Aneurysms for Training Neurosurgeons
by Pin-Chuan Chen, Jang-Chun Lin, Chung-Hsuan Chiang, Yi-Chin Chen, Jia-En Chen and Wei-Hsiu Liu
Polymers 2020, 12(12), 2901; https://doi.org/10.3390/polym12122901 - 3 Dec 2020
Cited by 9 | Viewed by 2472
Abstract
Neurosurgeons require considerable expertise and practical experience in dealing with the critical situations commonly encountered during difficult surgeries; however, neurosurgical trainees seldom have the opportunity to develop these skills in the operating room. Therefore, physical simulators are used to give trainees the experience [...] Read more.
Neurosurgeons require considerable expertise and practical experience in dealing with the critical situations commonly encountered during difficult surgeries; however, neurosurgical trainees seldom have the opportunity to develop these skills in the operating room. Therefore, physical simulators are used to give trainees the experience they require. In this study, we created a physical simulator to assist in training neurosurgeons in aneurysm clipping and the handling of emergency situations during surgery. Our combination of additive manufacturing with molding technology, elastic material casting, and ultrasonication-assisted dissolution made it possible to create a simulator that realistically mimics the brain stem, soft brain lobes, cerebral arteries, and a hollow transparent Circle of Willis, in which the thickness of vascular walls can be controlled and aneurysms can be fabricated in locations where they are likely to appear. The proposed fabrication process also made it possible to limit the error in overall vascular wall thickness to just 2–5%, while achieving a Young’s Modulus closely matching the characteristics of blood vessels (~5%). One neurosurgical trainee reported that the physical simulator helped to elucidate the overall process of aneurysm clipping and provided a realistic impression of the tactile feelings involved in this delicate operation. The trainee also experienced shock and dismay at the appearance of leakage, which could not immediately be arrested using the clip. Overall, these results demonstrate the efficacy of the proposed physical simulator in preparing trainees for the rigors involved in performing highly delicate neurological surgical operations. Full article
(This article belongs to the Special Issue Polymer Micro/Nanofabrication and Manufacturing)
►▼ Show Figures

Graphical abstract

15 pages, 5203 KiB  
Article
Polymer Microchannel and Micromold Surface Polishing for Rapid, Low-Quantity Polydimethylsiloxane and Thermoplastic Microfluidic Device Fabrication
by Chia-Wen Tsao and Zheng-Kun Wu
Polymers 2020, 12(11), 2574; https://doi.org/10.3390/polym12112574 - 2 Nov 2020
Cited by 5 | Viewed by 3436
Abstract
Polymer-based micromolding has been proposed as an alternative to SU-8 micromolding for microfluidic chip fabrication. However, surface defects such as milling marks may result in rough microchannels and micromolds, limiting microfluidic device performance. Therefore, we use chemical and mechanical methods for polishing polymer [...] Read more.
Polymer-based micromolding has been proposed as an alternative to SU-8 micromolding for microfluidic chip fabrication. However, surface defects such as milling marks may result in rough microchannels and micromolds, limiting microfluidic device performance. Therefore, we use chemical and mechanical methods for polishing polymer microchannels and micromolds. In addition, we evaluated their performance in terms of removing the machining (milling) marks on polymer microchannel and micromold surfaces. For chemical polishing, we use solvent evaporation to polish the sample surfaces. For mechanical polishing, wool felt polishing bits with an abrasive agent were employed to polish the sample surfaces. Chemical polishing reduced surface roughness from 0.38 μm (0 min, after milling) to 0.13 μm after 6 min of evaporation time. Mechanical polishing reduced surface roughness from 0.38 to 0.165 μm (optimal pressing length: 0.3 mm). As polishing causes abrasion, we evaluated sample geometry loss after polishing. Mechanically and chemically polished micromolds had optimal micromold distortion percentages of 1.01% ± 0.76% and 1.10% ± 0.80%, respectively. Compared to chemical polishing, mechanical polishing could better maintain the geometric integrity since it is locally polished by computer numerical control (CNC) miller. Using these surface polishing methods with optimized parameters, polymer micromolds and microchannels can be rapidly produced for polydimethylsiloxane (PDMS) casting and thermoplastic hot embossing. In addition, low-quantity (15 times) polymer microchannel replication is demonstrated in this paper. Full article
(This article belongs to the Special Issue Polymer Micro/Nanofabrication and Manufacturing)
►▼ Show Figures

Graphical abstract

10 pages, 2481 KiB  
Article
One-Step Hot Microembossing for Fabrication of Paper-Based Microfluidic Chips in 10 Seconds
by Yi-Je Juang, Yu Wang and Shu-Kai Hsu
Polymers 2020, 12(11), 2493; https://doi.org/10.3390/polym12112493 - 27 Oct 2020
Cited by 6 | Viewed by 2042
Abstract
In recent years, microfluidic paper-based analytical devices (µPADs) have been developed because they are simple, inexpensive and power-free for low-cost chemical, biological and environmental detection. Moreover, paper is lightweight; easy to stack, store and transport; biodegradable; biocompatible; good for colorimetric tests; flammable for [...] Read more.
In recent years, microfluidic paper-based analytical devices (µPADs) have been developed because they are simple, inexpensive and power-free for low-cost chemical, biological and environmental detection. Moreover, paper is lightweight; easy to stack, store and transport; biodegradable; biocompatible; good for colorimetric tests; flammable for easy disposal of used paper-based diagnostic devices by incineration; and can be chemically modified. Different methods have been demonstrated to fabricate µPADs such as solid wax printing, craft cutting, photolithography, etc. In this study, one-step hot microembossing was proposed and demonstrated to fabricate µPADs. The processing parameters like embossing temperature, pressure and time were systematically investigated. It was found that, at 55 °C embossing temperature, the embossing pressure ranging from 10 to 14 MPa could be applied and the embossing time was only 5 s. This led to the overall processing time for fabrication of µPADs within 10 s. Glucose detection was conducted using the µPADs as fabricated, and a linear relationship was obtained between 5 and 50 mM. Full article
(This article belongs to the Special Issue Polymer Micro/Nanofabrication and Manufacturing)
►▼ Show Figures

Graphical abstract

Review

Jump to: Editorial, Research

18 pages, 2944 KiB  
Review
Fabrication of Polymer Microfluidics: An Overview
by Yi-Je Juang and Yu-Jui Chiu
Polymers 2022, 14(10), 2028; https://doi.org/10.3390/polym14102028 - 16 May 2022
Cited by 18 | Viewed by 3956
Abstract
Microfluidic platform technology has presented a new strategy to detect and analyze analytes and biological entities thanks to its reduced dimensions, which results in lower reagent consumption, fast reaction, multiplex, simplified procedure, and high portability. In addition, various forces, such as hydrodynamic force, [...] Read more.
Microfluidic platform technology has presented a new strategy to detect and analyze analytes and biological entities thanks to its reduced dimensions, which results in lower reagent consumption, fast reaction, multiplex, simplified procedure, and high portability. In addition, various forces, such as hydrodynamic force, electrokinetic force, and acoustic force, become available to manipulate particles to be focused and aligned, sorted, trapped, patterned, etc. To fabricate microfluidic chips, silicon was the first to be used as a substrate material because its processing is highly correlated to semiconductor fabrication techniques. Nevertheless, other materials, such as glass, polymers, ceramics, and metals, were also adopted during the emergence of microfluidics. Among numerous applications of microfluidics, where repeated short-time monitoring and one-time usage at an affordable price is required, polymer microfluidics has stood out to fulfill demand by making good use of its variety in material properties and processing techniques. In this paper, the primary fabrication techniques for polymer microfluidics were reviewed and classified into two categories, e.g., mold-based and non-mold-based approaches. For the mold-based approaches, micro-embossing, micro-injection molding, and casting were discussed. As for the non-mold-based approaches, CNC micromachining, laser micromachining, and 3D printing were discussed. This review provides researchers and the general audience with an overview of the fabrication techniques of polymer microfluidic devices, which could serve as a reference when one embarks on studies in this field and deals with polymer microfluidics. Full article
(This article belongs to the Special Issue Polymer Micro/Nanofabrication and Manufacturing)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-16
Back to TopTop