PLA
PLA (polylactic acid) is made from biological materials which can be corn starch
or sugar cane, which makes it biodegradable. Like other corn or sugar-based
materials, it is slowly broken down by many common bacteria. However, it will
last a long time under normal conditions, so you have to e.g. do not throw it
in the compost pile.
It melts at 180-220 ° C, depending
on what other materials are added. PLA begins to deform at temperatures above
60 ° C, it is not water or chemical resistant. PLA has a strong layer bonding,
but the material itself is brittle and less elastic.
There is a wide range of PLA
mixtures, containing wood, (plastic added to fibers), metal, luminescent
(plastic added to phosphorescent pigment). There are variants of PLA that make
it both less crispy and more heat tolerant. Some varieties require that you
harden them in an oven, to achieve the desired strength. However, this allows
the workpiece to shrink slightly, which can be important to take into account
if it is a functional part where tolerances are important.
When printed with PLA, it emits a
sweet scent. Unlike ABS, it does not emit toxic fumes, so a cabinet is not
necessary. In general, PLA is less temperamental and requires a lower
temperature to print with than e.g. ABS and does not need a heated print bed.
PLA
is generally easier to print with than e.g. ABS or PETG, but finishing is more
cumbersome.