Page 8 - KVIS Book

ENG05A

DEVELOPMENT OF BIO-BASED COMPATIBILIZED PLA/NR

BLENDS AND DIY MINI-EXTRUDER FOR FABRICATION OF 3D
PRINTING FILAMENTS

Pattiya Pibulchinda
Kamnoetvidya Science Academy, Thailand
Supervisor: Sarun Nounjeen, Panuphong Pootawang, Min Medhisuwakul
Email: p.pibulchinda@gmail.com

3D printing is an innovative technique that is applicable to many fields. Biodegradable
polylactic acid (PLA) is widely used as filament in 3D printing but its properties, such as
its high brittleness, poor crystallization and cost, make it unsuitable for making
commercial products. Herein our project studies way to minimize the production cost
of 3D printing filament as well as ways to improve the toughness of PLA. We made “do
it yourself” (DIY) filaments containing PLA and natural rubber (NR) from PLA: NR blends
with 90:10, 85:15, and 80:20 weight compositions. In addition, compatibilized PLA/NR
blends were prepared. PLA/NR blends were extruded using the GreenHero Mini-
Extruder that has been designed and assembled by our team to produce filament (1.75
mm in diameter). From characterizations, SEM images show that the NR phase was
dispersed in PLA as an immiscible characteristic. Maleic anhydride (MA) was employed
to enhance the compatibility of NR in PLA matrix, which may improve toughness of the
PLA/NR filaments. For mechanical properties, the elongation at break of PLA90/NR10
filament showed the greatest improvement compared to neat PLA. The PLA/NR blend
filaments were then used in a fused deposition modeling (FDM) 3D printer to fabricate
prototype samples.