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Materials Science in Additive Manufacturing Cellulose microfiber in ABS filament for 3D printing

relies on eight enabling technologies: internet of things, Plant cellulose is the most abundant polymer on
cloud computing, big data, advanced robotics, additive earth . It presents a rigid linear chain of glucose
[11]
manufacturing, digital manufacturing, digital security, and molecules and a morphological aspect of a flat ribbon.
systems integration . According to Redwood et al., there The repeating unit of cellulose is composed of two rings
[1]
are three main three-dimensional (3D) manufacturing of anhydrous glucose (C H O ) , in which the “n” varies
5
10
5 n
processes: (i) Formative manufacturing, which uses molds between 10,000 and 15,000 depending on the source of
to produce components; (ii) subtractive manufacturing, the material . The crystalline component of cellulose
[12]
which removes parts from a larger block to compose parts; has a microfiber structure that, when isolated, has
and (iii) additive manufacturing, in which components are been considered an important reinforcement material
formed by the successive deposition of specific materials . in polymeric matrices due to its potential to improve
[2]
Fused filament fabrication (FFF) 3D printing is an mechanical properties [13,14] .
additive manufacturing process included in the field of This present study addresses the production of
material extrusion. FFF allows the manufacture of pieces filaments for 3D printing, using pure ABS copolymer or
in multilayer systems, selectively depositing the molten ABS composite with cellulose microfibers as raw material.
material in a path predetermined through software . Mechanical properties of specimens extruded through
[3]
Conventionally, this technology has used thermoplastic FFF, assessed by traction, flexion, impact, and melt flow
polymers in filaments to form the final physical objects. In index tests, were characterized.
the FFF method, the filament is fused by the printer head
simultaneously while the extruder nozzle deposits the 2. Study objectives and justifications
desired 3D model layer by layer. The filament is melted and Increasing the use of wood residues has been proven
deposited under controlled temperature, ensuring adequate by recent studies to be a slightly effective measure in
polymer workability, and obtaining a cohesive piece [4,5] . reducing net carbon emissions into the atmosphere in
ABS is a copolymer composed of acrylonitrile the short to medium term [15-17] . On the other hand, the
butadiene styrene, with a styrene-acrylonitrile matrix increasingly greater use of waste in the production chain is
(SAN), spherical domains composed of polybutadiene a fundamental measure in the implementation of circular
rubber, and SAN sub-inclusions in the spherical economy policies [18,19] . Wood waste can be very voluminous
[6]
polybutadiene particles . According to Kulich et al., and, consequently, is a significant challenge to solid waste
the styrene monomer gives ABS good processability, management, which is reflected in a very significant
acrylonitrile rigidity, and thermal and chemical resistance, concern in the specialized scientific literature [20-27] .
while the butadiene makes the product more resilient at Brazil is a forestry country with 7.7 million hectares of
low temperatures . ABS has poor weather resistance and planted and natural forests, representing the second largest
[7]
is therefore recommended for indoor applications. In 3D area of forests in the world, surpassed only by Russia .
[28]
printing, ABS is indicated for obtaining parts with complex Brazil was also one of the ten largest producers of wood
geometries, and in some of these applications, better fiber in the world, ranked sixth in 2019. In 2020, Brazil
mechanical properties, rather than those presented by pure was the world’s largest exporter of cellulose, reaching more
ABS, are required, necessitating the combination of ABS than 16,000 tons .
[29]
with some type of reinforcement to adapt its performance. The E. grandis species is widely cultivated in Brazil [30,31] ,
It is noteworthy that ABS is a polymer incorporated with and its production is certified by the Forest Stewardship
fillers and additives .
[8]
Council (FSC). This species is widely used for reforestation
Eucalyptus grandis is one of the most important around the world [32-34] . Given the relevance of E. grandis
commercial species of eucalyptus, with over half a million and cellulose in the global context, as well as the huge
hectares of land planted with this species in tropical production of wood fibers in Brazil, we used wood derived
and subtropical areas on four continents. Despite being from this species in the present study to obtain crystalline
a species native to the east coast of Australia, massive cellulose microfibers, which were used in the ABS
planting programs have been carried out in the Republic of composite for 3D-printing filaments. The co-processing
South Africa and Brazil, and there are substantial plantings of cellulose in a progressively growing industry, using
in Angola, Argentina, India, Uruguay, Zaire, Zambia, technologies such as 3D printing, may facilitate the
and Zimbabwe . According to Meskimen and Francis, management of wood waste, if the material does not
[9]
E. grandis has been successfully tested for cellulose and fuel compromise the properties of the polymeric matrix, or if
production . E. grandis, as it is a natural renewable source it behaves as an additive. The possibility of co-processing
[10]
of cellulose, was used in this research to obtain microfibers. is evaluated by this work.

Volume 2 Issue 2 (2023) 2 https://doi.org/10.36922/msam.1000