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This page was created as part of the 2017 Aalto University course L3999 3D Printing of Open Source Hardware for Science.It's open edit now, so feel free to improve it.Read more...

This is a literature review for a study on the chemical resistance of 3D printable polymers. This literature review is initially targeted at liquid chemicals which can "attack" 3D printed polymers. In the future gas and plasma attack can be studied but for now it is out of the scope of this lit review.

Introduction

Our target is to find out what FFF (fused filament fabrication) 3D printing filaments tolerate the harsh chemicals that we use in semiconductor processing and other cleanroom processes. FFF was chosen as the preferred 3D printing method thanks to its versatility, cost-effectivity and relative ease. 3D printing filaments are made from plastics by using additives (plasticizers and colorants), and the vendors rarely or ever provide the information on them to the customer. Therefore, it is not guaranteed that if a certain polymer tolerates, for example, HCl, 3D printed objects made from the same polymer could be used to make custom labware. Further on, we do not know if the printing (thermoplastic extrusion) itself changes the chemical properties of the materials.

Polypropylene (PP) is a 3D printable polymer that can tolerate many chemicals, and the authors of articles listed below have made reaction vessels and microfluidics applications from it. But are we limited to PP? In this we need to search for clues in chemical compatibility charts, also found below.

We will experiment on 3D printing filaments and 3D printed objects by testing them in different chemicals and observing if they swell or dissolve.

Sources

Journal Articles

Integrated 3D-printed reactionware for chemical synthesis and analysis

Mark D. Symes, Philip J. Kitson, Jun Yan, Craig J. Richmond, Geoffrey J. T. Cooper, Richard W. Bowman, Turlif Vilbrandt & Leroy Cronin, Nature Chemistry 4, 349–354 (2012), doi:10.1038/nchem.1313

• Reactionware for inorganic and organic synthesis
• Reactionware: combines reaction vessel combined with reagents, catalysts, or control of shape to produce a desired result
• Printed-in: catalysts and in-situ characterization
• Modifying the geometry changes the outcome of the reaction
• Robocasting of acetoxysilicone polymer (Loctite 5366): does not require heat, the material hardens quickly.
• The properties of the material modified by e.g. mixing in conductive carbon black
• Reusable reactionware, cleaved reactor could be glued shut again with the same material after cutting it open

Configurable 3D-Printed millifluidic and microfluidic ‘lab on a chip’ reactionware devices

Philip J. Kitson, Mali H. Rosnes, Victor Sans, Vincenza Dragone and Leroy Cronin, Lab Chip, 2012, 12, 3267–3271. DOI: 10.1039/c2lc40761b

• Millifluidic devices, made using PP (FFF, 3DTouch printer)
• Properties of PP: robust, flexible, chemically inert, low cost
• Three different millifluidic devices were made and demonstrated
• Containers for solid materials were filled during printing and the printing was continued, which sealed the containers
• Time and cost-effective method compared to traditional methods, single device takes only hours to build
• Future interest: solvent compatibility

Continuous parallel ESI-MS analysis of reactions carried out in a bespoke 3D printed device

Jennifer S. Mathieson, Mali H. Rosnes, Victor Sans, Philip J. Kitson and Leroy Cronin, Beilstein J. Nanotechnol. 2013, 4, 285–291. doi:10.3762/bjnano.4.31

• 3D printed tailored deviced linked to a mass spectrometer
• 3DTouch printer used to print thermoplastic PP
• PP: low cost, robust, flexible, chemically inert
• Screw fittings made from PEEK (harder than PP), provides a tighter seal

Combining 3D printing and liquid handling to produce user-friendly reactionware for chemical synthesis and purification

Philip J. Kitson , Mark D. Symes , Vincenza Dragone and Leroy Cronin, Chem. Sci., 2013, 4, 3099-3103. DOI: 10.1039/C3SC51253C

• Reactionware for a multi-step reaction was made, step control by rotating the device and letting gravity do the work -> need for pumps eliminated
• Approaches from earlier articles combined: vessel was printed from PP, liquid-handling robot was used to functionalize the vessel
• PP: melting point approx. 160°C, maximum working temperature 150°C
• PP impermeable to hexane and diethly ether vapors, pressure build-up might need to be mitigated

Evaluation of 3D Printing and Its Potential Impact on Biotechnology and the Chemical Sciences

Bethany C. Gross, Jayda L. Erkal, Sarah Y. Lockwood, Chengpeng Chen, and Dana M. Spence, Anal. Chem., 2014, 86 (7), pp 3240–3253, DOI: 10.1021/ac403397r

• Common FDM/FFF materials: PC, ABS, PS, nylon, metals/ceramics
• Many polymeric materials absorb small organic molecules, can also absorb organic or aqueous solvents. This can results in swelling of the bulk material

3D Printed High-Throughput Hydrothermal Reactionware for Discovery, Optimization, and Scale-Up

Philip J. Kitson, Ross J. Marshall, Deliang Long, Ross S. Forgan, and Leroy Cronin, Angew. Chem. Int. Ed. 2014, 53, 12723 –12728 . DOI: 10.1002/anie.201402654

• Sealed monolithic reaction vessels from PP for hydrothermal synthesis. Array reactor, which allowed multiple experiments during one heating step.
• Considerable savings achieved with 3D printed vessels compared to commercial alternatives
• Another advantage: quick prototyping and ease of tailoring cheaply
• FDM/FFF of PP
• PP starts to soften at 150°C, some reactors burst in the heating due to pressure build-up. Reactors were safe for aqueous/DMF solutions over 72 hours at 140°C.

3D printed microfluidic devices with integrated versatile and reusable electrodes

Jayda L. Erkal, Asmira Selimovic , Bethany C. Gross, Sarah Y. Lockwood, Eric L. Walton, Stephen McNamara, R. Scott Martin, and Dana M. Spence, Lab Chip, 2014, 14, 2023-2032. DOI: 10.1039/C4LC00171K

• 3D printed devices, used in electrochemical detection. Printed using Objet Connex 350, material VeroClear (acrylate-based polymer).
• Many electrode materials integrated in these devices for applications in e.g. detecting neurotransmitters, NO.
• CADs and 3D printing: custom parts fitted into commercial equipment, rapid troubleshooting, easy to share designs with others.

3D printing of versatile reactionware for chemical synthesis

Philip J. Kitson, Stefan Glatzel, Wei Chen, Chang-Gen Lin, Yu-Fei Song,and Leroy Cronin, Nat. Protocols, 2016, 11 (5), 920-936

• Describes the steps for making 3D printed reactionware
• Open-source type development driving the growth of 3D printing
• Advantages of 3D printing in chemistry: topology, geometry and composition of reactors precisely controlled
• The versatility of 3DP materials is an advantage, but all of their applications impossible to describe in a single document
• Extrusion-based methods (FFF/FDM) popular and economical, PLA and ABS most common materials
• FDM applied in making fluidic reactors, but for the most part research focused on 3D printable materials, post-treatments, and batteries and LEDs
• Limitations: epoxy- and acrylate-based materials used in SL not resistant organic solvents or extreme pHs. Similar problems for PLA and ABS.
• FFF/FDM of nylon and PP more promising for chemical applications
• Perfluorinated polymers difficult to print (small temperature window) and toxic.
• Conventional FFF/FDM materials suitable for biological labware (water solutions, mild pH)
• Choosing a material: inert to the desired chemistry. The author's choice: PP. Easy to print, good resolution and chemically inert.
• PP attacked by very strong oxidizers, also by heated solvents (toluene)
• Different grades of PP require different print settings (different melt profiles and flow)

Chemical resistance charts

• Rosemount analytical huge chart, resistance as a function of temperature
• Curbell Plastics
• Thermo Scientific Nalgene Products, Cornell University Sevier lab
• Ensinger Plastics
• Sirmax

Books

• Schreirs, J. Modern fluoropolymers. Scheirs, J., Ed (1997): 32.
• Moiseev, Yu V., and Gennadiĭ Efremovich Zaikov. Chemical resistance of polymers in aggressive media. Springer Science & Business Media, 1987.
• Seymour R.B., Carraher C.E. (1984) Chemical Resistance of Polymers. In: Structure—Property Relationships in Polymers. Springer, Boston, MA.

3D printing materials and their chemical properties

ABS (Acrylonitrile butadiene styrene)

One of the most used 3D printing filaments. Various vendors and available in multiple colors. Potentially more resistant to water and other chemicals than PLA.

According to Curbell plastics, resistant to following chemicals:

• Acetic acid 5%
• Acetic acid 10%
• Ammonia solution 10%
• Ethanol 96%
• HCl 2%
• HCl 36%
• H2O2 30%
• H3PO4 10%
• H3PO4 concentrated
• H2SO4 2%
• H2O cold
• H2O warm

Limited resistance to:

• HF 40%
• IPA

Not resistant to:

• Acetic acid concentrated
• Acetone
• HNO3 2% (NOTE: Ensinger chart mentions that Tecaran ABS is resistant to this)
• H2SO4 98%

ASA (Acrylonitrile styrene acrylate)

Acrylonitrile styrene acrylate, structurally similar to ABS but with improved UV resistivity and mechanical properties. Slightly hygroscopic.

Co-polyesters

Commercial 3D printing filaments: Inova Co-Polyester, ColorFabb nGen. No mentions of chemical properties, not advertised as a chemically resistant material.

FEP (Fluorinated ethylene propylene)

Should be in the sweet spot of fluoropolymers. Low enough melting point to be printable but chemically very durable. According to some data should be resistant to nearly all room temperature liquid chemicals used in clean rooms.

Nylon

Taulman Alloy 910 is apparently Nylon-based. Is advertised as chemically resistant, but presumable absorbs a lot water.

According to Curbell plastics, Nylon 6 is resistant to following chemicals:

• Acetic acid 5%
• Ammonia solution 10%
• Ethanol 96%
• IPA
• H2O cold

Limited resistance to:

• Acetone
• H2O warm

Not resistant to:

• Acetic acid concentrated
• Acetic acid 10%
• HCl 2%
• HCl 36%
• HF 40%
• H2O2 30%
• HNO3 2%
• H3PO4 10%
• H3PO4 concentrated
• H2SO4 2%
• H2SO4 98%

PC (Polycarbonate)

According to Curbell plastics, resistant to following chemicals:

• Acetic acid 5%
• Acetic acid 10%
• HCl 2%
• HCl 36%
• HNO3 2%
• H3PO4 10%
• H3PO4 concentrated
• H2SO4 2%
• H2O cold
• H2O2 30% (according to Ensinger table)

Limited resistance to:

• Ethanol 96%
• HF 40%
• IPA
• H2O warm

Not resistant to:

• Acetic acid concentrated
• Acetone
• Ammonia solution 10%
• H2SO4 98%

PEI (Polyetherimide)

Ultem(R) is a commercial name for a family of PEI products.

According to Curbell plastics and Ensinger, Ultem(R) is resistant to following chemicals:

• Acetic acid 5%
• Acetic acid 10%
• Ethanol 96%
• HCl 2%
• HCl 36%
• IPA
• HNO3 2%
• H3PO4 10%
• H2SO4 2%
• H2O cold

Limited resistance to:

• H2O2 30%

Not resistant to:

• Acetic acid concentrated
• Acetone
• Ammonia solution 10%
• HF 40%
• H2SO4 98%

Other:

• Conflicting information in the charts for H2O warm
• No data available for H3PO4 concentrated

PETG (Polyethylene terephthalate modified with glycol)

PET is used in plastic bottles and food packaging, while PETG (Polyethylene terephthalate modified with glycol) is used in 3D printing. Glass transition temperature 88°C, less brittle than PET.

PETT (Polyethylene coTrimethylene Terephthalate)

Another variant to PET, transparent. Taulman T-glase is made of PETT.

PLA (Polylactic acid)

One of the most used 3D printing filaments. Various vendors and available in multiple colors. Biodegradable, potentially not very resistant to chemicals.

PP (Polypropylene)

Resistant to various laboratory chemicals. Quite resistant to acids and bases. Widely used in clean rooms. Is susceptible to oxidation for example peroxides, as it is just a hydrocarbon. 3D printed polypropylene demonstrated in various chemical applications by Kitson et al.

According to Curbell plastics, resistant to following chemicals:

• Acetic acid 5%
• Acetic acid 10%
• Acetic acid concentrated
• Acetone
• Ammonia solution 10%
• Ethanol 96%
• HCl 2%
• HCl 36%
• HF 40%
• H2O2 30%
• IPA
• HNO3 2%
• H3PO4 10% (according to Ensinger table
• H3PO4 concentrated
• H2SO4 2%
• H2SO4 98%
• H2O cold
• H2O warm

Limited resistance to:

• Acetic acid concentrated (according to Ensinger table
• H2O warm (according to Ensinger table

Not resistant to: -

Searches

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