UV-curable silicone materials with tuneable mechanical properties for 3D printing

The recognition of nanocellulose has been prominent in recent years as prospect materials, yet the ineffectiveness of nanocellulose to disperse in an organic solvent has restricted its utilization, especially as a reinforcement in polymer nanocomposite. In this study, cellulose has been isolated and defibrillated as cellulose nanofibrils (CNF) from oil palm empty fruit bunch (EFB) fibers. Subsequently, to enhance its compatibility with UV-curable polyurethane (PU)-based resin, the surface hydrophilicity of CNF has been tailored with polyethylene glycol (PEG), as well as reduced graphene oxide (rGO). The dispersibility of reinforced modified CNF in UV-curable PU was examined through the transmittance interruption of resin, chemical, and mechanical properties of the composite printed using the stereolithographic technique. Evidently, the enhanced compatibility of modified CNF and UV-curable PU was shown to improve the tensile strength and hardness of the composites by 37% and 129%, respectively.

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Polymerizable Choline- and Imidazolium-Based Ionic Liquids Reinforced with Bacterial Cellulose for 3D-Printing

Polymers ◽

10.3390/polym13183044 ◽

2021 ◽

Vol 13 (18) ◽

pp. 3044

Author(s):

Michael A. Smirnov ◽

Veronika S. Fedotova ◽

Maria P. Sokolova ◽

Alexandra L. Nikolaeva ◽

Vladimir Yu. Elokhovsky ◽

...

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Acrylic Acid ◽

Bacterial Cellulose ◽

Choline Chloride ◽

Cellulose Nanofibers ◽

Uv Curable ◽

Shear Rates ◽

Novel Approach ◽

Ion Gels

In this work, a novel approach is demonstrated for 3D-printing of bacterial cellulose (BC) reinforced UV-curable ion gels using two-component solvents based on 1-butyl-3-methylimidazolium chloride or choline chloride combined with acrylic acid. Preservation of cellulose’s crystalline and nanofibrous structure is demonstrated using wide-angle X-ray diffraction (WAXD) and atomic force microscopy (AFM). Rheological measurements reveal that cholinium-based systems, in comparison with imidazolium-based ones, are characterised with lower viscosity at low shear rates and improved stability against phase separation at high shear rates. Grafting of poly(acrylic acid) onto the surfaces of cellulose nanofibers during UV-induced polymerization of acrylic acid results in higher elongation at break for choline chloride-based compositions: 175% in comparison with 94% for imidazolium-based systems as well as enhanced mechanical properties in compression mode. As a result, cholinium-based BC ion gels containing acrylic acid can be considered as more suitable for 3D-printing of objects with improved mechanical properties due to increased dispersion stability and filler/matrix interaction.

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Experimental investigation of mechanical properties of UV-Curable 3D printing materials

Polymer ◽

10.1016/j.polymer.2018.04.067 ◽

2018 ◽

Vol 145 ◽

pp. 88-94 ◽

Cited By ~ 16

Author(s):

Sung Yong Hong ◽

Ye Chan Kim ◽

Mei Wang ◽

Hyung-Ick Kim ◽

Do-Young Byun ◽

...

Keyword(s):

Mechanical Properties ◽

Experimental Investigation ◽

3D Printing ◽

Uv Curable

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3D Printing of High Viscosity Reinforced Silicone Elastomers

Polymers ◽

10.3390/polym13142239 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2239

Author(s):

Nicholas Rodriguez ◽

Samantha Ruelas ◽

Jean-Baptiste Forien ◽

Nikola Dudukovic ◽

Josh DeOtte ◽

...

Keyword(s):

Mechanical Properties ◽

High Performance ◽

New Technologies ◽

Three Dimensional ◽

High Viscosity ◽

Layer By Layer ◽

Silicone Elastomers ◽

Uv Curable ◽

Octet Truss ◽

Tunable Mechanical Properties

Recent advances in additive manufacturing, specifically direct ink writing (DIW) and ink-jetting, have enabled the production of elastomeric silicone parts with deterministic control over the structure, shape, and mechanical properties. These new technologies offer rapid prototyping advantages and find applications in various fields, including biomedical devices, prosthetics, metamaterials, and soft robotics. Stereolithography (SLA) is a complementary approach with the ability to print with finer features and potentially higher throughput. However, all high-performance silicone elastomers are composites of polysiloxane networks reinforced with particulate filler, and consequently, silicone resins tend to have high viscosities (gel- or paste-like), which complicates or completely inhibits the layer-by-layer recoating process central to most SLA technologies. Herein, the design and build of a digital light projection SLA printer suitable for handling high-viscosity resins is demonstrated. Further, a series of UV-curable silicone resins with thiol-ene crosslinking and reinforced by a combination of fumed silica and MQ resins are also described. The resulting silicone elastomers are shown to have tunable mechanical properties, with 100–350% elongation and ultimate tensile strength from 1 to 2.5 MPa. Three-dimensional printed features of 0.4 mm were achieved, and complexity is demonstrated by octet-truss lattices that display negative stiffness.

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Scientometric Review of Trends on the Mechanical Properties of Additive Manufacturing and 3D Printing

Journal of Materials Engineering and Performance ◽

10.1007/s11665-021-05524-7 ◽

2021 ◽

Author(s):

R. A. García-León ◽

J. A. Gómez-Camperos ◽

H. Y. Jaramillo

Keyword(s):

Mechanical Properties ◽

Additive Manufacturing ◽

3D Printing

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An Overview on the Rheology, Mechanical Properties, Durability, 3D Printing, and Microstructural Performance of Nanomaterials in Cementitious Composites

Materials ◽

10.3390/ma14112950 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2950

Author(s):

Hongwei Song ◽

Xinle Li

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Three Dimensional ◽

Cementitious Materials ◽

Research Area ◽

Cementitious Composites ◽

Split Tensile Strength ◽

Contour Crafting ◽

Wide Range ◽

Active Research

The most active research area is nanotechnology in cementitious composites, which has a wide range of applications and has achieved popularity over the last three decades. Nanoparticles (NPs) have emerged as possible materials to be used in the field of civil engineering. Previous research has concentrated on evaluating the effect of different NPs in cementitious materials to alter material characteristics. In order to provide a broad understanding of how nanomaterials (NMs) can be used, this paper critically evaluates previous research on the influence of rheology, mechanical properties, durability, 3D printing, and microstructural performance on cementitious materials. The flow properties of fresh cementitious composites can be measured using rheology and slump. Mechanical properties such as compressive, flexural, and split tensile strength reveal hardened properties. The necessary tests for determining a NM’s durability in concrete are shrinkage, pore structure and porosity, and permeability. The advent of modern 3D printing technologies is suitable for structural printing, such as contour crafting and binder jetting. Three-dimensional (3D) printing has opened up new avenues for the building and construction industry to become more digital. Regardless of the material science, a range of problems must be tackled, including developing smart cementitious composites suitable for 3D structural printing. According to the scanning electron microscopy results, the addition of NMs to cementitious materials results in a denser and improved microstructure with more hydration products. This paper provides valuable information and details about the rheology, mechanical properties, durability, 3D printing, and microstructural performance of cementitious materials with NMs and encourages further research.

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Mechanical properties of engineered cementitious composites beams fabricated by extrusion-based 3D printing

Engineering Structures ◽

10.1016/j.engstruct.2021.112201 ◽

2021 ◽

Vol 238 ◽

pp. 112201

Author(s):

Binrong Zhu ◽

Jinlong Pan ◽

Zhenxin Zhou ◽

Jingming Cai

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Cementitious Composites ◽

Engineered Cementitious Composites

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Extrusion Based 3D Printing of Sustainable Biocomposites from Biocarbon and Poly(trimethylene terephthalate)

Molecules ◽

10.3390/molecules26144164 ◽

2021 ◽

Vol 26 (14) ◽

pp. 4164

Author(s):

Elizabeth Diederichs ◽

Maisyn Picard ◽

Boon Peng Chang ◽

Manjusri Misra ◽

Amar Mohanty

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Surface Finish ◽

Three Dimensional ◽

Morphological Properties ◽

Great Promise ◽

Structural Components ◽

Computer Aided ◽

Trimethylene Terephthalate ◽

Optimal Quantity

Three-dimensional (3D) printing manufactures intricate computer aided designs without time and resource spent for mold creation. The rapid growth of this industry has led to its extensive use in the automotive, biomedical, and electrical industries. In this work, biobased poly(trimethylene terephthalate) (PTT) blends were combined with pyrolyzed biomass to create sustainable and novel printing materials. The Miscanthus biocarbon (BC), generated from pyrolysis at 650 °C, was combined with an optimized PTT blend at 5 and 10 wt % to generate filaments for extrusion 3D printing. Samples were printed and analyzed according to their thermal, mechanical, and morphological properties. Although there were no significant differences seen in the mechanical properties between the two BC composites, the optimal quantity of BC was 5 wt % based upon dimensional stability, ease of printing, and surface finish. These printable materials show great promise for implementation into customizable, non-structural components in the electrical and automotive industries.

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Exceptional Mechanical Properties and Heat Resistance of Photocurable Bismaleimide Ink for 3D Printing

Materials ◽

10.3390/ma14071708 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1708

Author(s):

Wenqiang Hua ◽

Qilang Lin ◽

Bo Qu ◽

Yanyu Zheng ◽

Xiaoying Liu ◽

...

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Heat Resistance ◽

Three Dimensional ◽

Mechanical And Thermal Properties ◽

Amino Group ◽

Building Models ◽

Fast Processing ◽

Forming Precision ◽

Complex Structural

Photosensitive resins used in three-dimensional (3D) printing are characterized by high forming precision and fast processing speed; however, they often possess poor mechanical properties and heat resistance. In this study, we report a photocurable bismaleimide ink with excellent comprehensive performance for stereolithography (SLA) 3D printing. First, the main chain of bismaleimide with an amino group (BDM) was synthesized, and then, the glycidyl methacrylate was grafted to the amino group to obtain the bismaleimide oligomer with an unsaturated double bond. The oligomers were combined with reaction diluents and photo-initiators to form photocurable inks that can be used for SLA 3D printing. The viscosity and curing behavior of the inks were studied, and the mechanical properties and heat resistance were tested. The tensile strength of 3D-printed samples based on BDM inks could reach 72.6 MPa (166% of that of commercial inks), glass transition temperature could reach 155 °C (205% of that of commercial inks), and energy storage modulus was 3625 MPa at 35 °C (327% of that of commercial inks). The maximum values of T-5%, T-50%, and Tmax of the 3D samples printed by BDM inks reached 351.5, 449.6, and 451.9 °C, respectively. These photocured BDM inks can be used to produce complex structural components and models with excellent mechanical and thermal properties, such as car parts, building models, and pipes.

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Mechanical properties of structures produced by 3D printing from composite materials

MATEC Web of Conferences ◽

10.1051/matecconf/201925401018 ◽

2019 ◽

Vol 254 ◽

pp. 01018

Author(s):

František Bárnik ◽

Milan Vaško ◽

Milan Sága ◽

Marián Handrik ◽

Alžbeta Sapietová

Keyword(s):

Mechanical Properties ◽

Composite Materials ◽

3D Printing ◽

Carbon Fibers ◽

3D Printer

By 3D printing it is possible to create different structures with different fiber-laying directions. These structures can be created depending on the type of 3D printer and its software. The Mark Two printer allows printing Onyx, a material based on nylon in combination with microcarbon fibers. Onyx can be used alone or reinforced with kevlar, glass or carbon fibers. This article deals with 3D printing and evaluation of mechanical properties of printed samples.

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