Page 14 - ScienceFocus (Issue 014)
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Printing. The word itself sounds anything polybutadiene. Then, styrene and acrylonitrile
are polymerized with polybutadiene. The resultant
but high-tech. Printing documents and/or photos polymer is very strong as it combines the strength
has been around for a long time. I? fairly certain and rigidity of acrylonitrile and styrene polymers
all of you have used a printer before, at some point with the toughness of polybutadiene rubber.
in your life. Sounds pretty boring, eh? But what ABS is also a very resistant polymer, being able
if I told you that what you could print would no to withstand acid and alkali attacks as well as
longer be limited to two dimensions? What if I told mechanical impacts. This, combined with the fact
you that one could print out objects of all kinds, in that ABS has a relatively high melting point, makes it
different shapes and sizes? Yes, you?e got it: I am a favorite material for 3D printers.
talking about 3D printing, a technology hailed as
revolutionary. Alternatively, you could use PL A plastic in
your household printer instead of ABS plastic.
The principle of 3D printing actually isn? as PLA stands for polylactic acid. Due to its name,
complex as you might think. Say you want to print people commonly mistake PLA for a polyacid,
a cube. All you have to do is print a regular 2D but it is actually a polyester. Since the lactic
square, repeat the process, then stack all the layers acid monomer contains both a carboxyl group
up together until it becomes a cube. Once you (COOH) and a hydroxyl group (OH), PLA is
have enough layers, you can have any shape you simply produced by polymerizing lactic acid via
want. Simple. And once you have a basic shape condensation. Lactic acid used for PLA production
mastered, you can start moving onto the more is usually extracted from sugarcanes or any starch
complex shapes, for example, a sphere, using containing substance. As it comes from plants,
the same method. Or a basin, with some hollow PLA is considered a bioplastic, and since the ester
internal parts. With 3D printing, almost all shapes bonds within the PLA chains can be broken down
can be visualized and crafted. This is achieved by enzymatically, it is also a biodegradable plastic,
simple mechanics: all you need is a platform that unlike most thermoplastics. In comparison, PLA is
can move in 3 axes: X, Y and Z, and a nozzle gun less resistant to mechanical stress than ABS, making
to extrude printing material. But the question now it more prone to warping during the 3D print
process; this is mostly due to its lower melting point.
is, precisely what kind of printing However, it does produce a smoother surface that
material do you use for those is harder for ABS to achieve. It is also able to print
in much finer detail than ABS. So it would be more
layers? Surely, regular ink from precise in molding the desired shape, making PLA
the age-old 2D printers another favorite for printing materials in 3D printers.
won? work? Guess not.
As of now, household 3D printing is mostly used
What are the materials that to create quick prototypes for assessing their form
could best fit the 3D printing and function. With the use of different printing
purposes? The answer for this materials, it also helps to rapidly manufacture
products on a large industrial scale, especially
lies in chemistry. One those that require customization. In medicine,
of most common artificial bones and joints have been 3D-printed
materials used in for use as prosthetics. Some companies have even
household 3D printers dared to use 3D printing to construct housing, be it
is acrylonitrile butadiene for long term use or for temporary refugee housing.
st y rene. Well, what exactly is it? Let? just use its
abbreviation: ABS plastic. You may have already To sum up, 3D printing is a unique technology,
encountered ABS before you?e read this article: an interdisciplinary force of chemistry and
Lego blocks are in fact ABS plastic. Unlike the mechanics. It? quite like using play-doh to mold
(ordinary) polymers you may have learnt in high whatever objects you wish, but in a fancier, more
school, ABS plastic is actually made out of not precise way. It truly encapsulates the concept of
one, but three monomers, namely 1,3-butadiene, bringing abstract ideas to the physical world.
styrene and acrylonitrile. As such, ABS is known
specifically as a terpolymer, with ?er??meaning
three. The terpolymer is made in a series of steps.
First, 1,3-butadiene itself is polymerized, forming
