Poly-L-lactic Acid-based Filaments for Fused Deposition Modeling Typed 3D Printer with Improved Impact Strength and Crystallization Rate

Injured bone tissues can be healed with scaffolds, which could be manufactured using the fused deposition modeling (FDM) strategy. Poly(lactic acid) (PLA) is one of the most biocompatible polymers suitable for FDM, while hydroxyapatite (HA) could improve the bioactivity of scaffold due to its chemical composition. Therefore, the combination of PLA/HA can create composite filaments adequate for FDM and with high osteoconductive and osteointegration potentials. In this work, we proposed a different approache to improve the potential bioactivity of 3D printed scaffolds for bone tissue engineering by increasing the HA loading (20-30%) in the PLA composite filaments. Two routes were investigated regarding the use of solvents in the filament production. To assess the suitability of the FDM-3D printing process, and the influence of the HA content on the polymer matrix, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) were performed. The HA phase content of the composite filaments agreed with the initial composite proportions. The wettability of the 3D printed scaffolds was also increased. It was shown a greener route for obtaining composite filaments that generate scaffolds with properties similar to those obtained by the solvent casting, with high HA content and great potential to be used as a bone graft.

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Synthesis and properties of modified PBT for FDM

Rapid Prototyping Journal ◽

10.1108/rpj-12-2015-0197 ◽

2017 ◽

Vol 23 (4) ◽

pp. 804-810 ◽

Cited By ~ 2

Author(s):

Shiqing Cao ◽

Dandan Yu ◽

Weilan Xue ◽

Zuoxiang Zeng ◽

Wanyu Zhu

Keyword(s):

Mechanical Properties ◽

Impact Strength ◽

Fused Deposition Modeling ◽

Complex Structure ◽

Three Dimensional ◽

Sebacic Acid ◽

Wire Drawing ◽

Content Type ◽

Fused Deposition ◽

Deposition Modeling

Purpose The purpose of this paper is to prepare a new modified polybutylene terephalate (MPBT) for fused deposition modeling (FDM) to increase the variety of materials compatible with printing. And the printing materials can be used to print components with a complex structure and functional mechanical parts. Design/methodology/approach The MPBT, poly(butylene terephalate-co-isophthalate-co-sebacate) (PBTIS), was prepared for FDM by direct esterification and subsequent polycondensation using terephthalic acid (PTA), isophthalic acid (PIA), sebacic acid (SA) and 1,4-butanediol (BDO). The effects of the content of PIA (20-40 mol%) on the mechanical properties of PBTIS were investigated when the mole per cent of SA (αSA) is zero. The effects of αSA (0-7mol%) on the thermal, rheological and mechanical properties of PBTIS were investigated at nPTA/nPIA = 7/3. A desktop wire drawing and extruding machine was used to fabricate the filaments, whose printability and anisotropy were tested by three-dimensional (3D) printing experiments. Findings A candidate content of PIA introducing into PBT was obtained to be about 30 per cent, and the Izod notched impact strength of PBTIS increased with the increase of αSA. The results showed that the PBTIS (nPTA/nPIA = 7/3, αSA = 3-5mol%) is suitable for FDM. Originality/value New printing materials with good Izod notched impact strength were obtained by introducing PIA and SA (nPTA/nPIA = 7/3, αSA = 3-5 mol%) into PBT and their anisotropy are better than that of ABS.

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Dual Sacrificial Molding: Fabricating 3D Microchannels with Overhang and Helical Features

Micromachines ◽

10.3390/mi9100523 ◽

2018 ◽

Vol 9 (10) ◽

pp. 523 ◽

Cited By ~ 9

Author(s):

Wei Goh ◽

Michinao Hashimoto

Keyword(s):

3D Printing ◽

Fused Deposition Modeling ◽

Microfluidic Devices ◽

High Impact ◽

3D Printer ◽

Original Design ◽

Fused Deposition ◽

Deposition Modeling ◽

Indispensable Tool ◽

Single Material

Fused deposition modeling (FDM) has become an indispensable tool for 3D printing of molds used for sacrificial molding to fabricate microfluidic devices. The freedom of design of a mold is, however, restricted to the capabilities of the 3D printer and associated materials. Although FDM has been used to create a sacrificial mold made with polyvinyl alcohol (PVA) to produce 3D microchannels, microchannels with free-hanging geometries are still difficult to achieve. Herein, dual sacrificial molding was devised to fabricate microchannels with overhang or helical features in PDMS using two complementary materials. The method uses an FDM 3D printer equipped with two extruders and filaments made of high- impact polystyrene (HIPS) and PVA. HIPS was initially removed in limonene to reveal the PVA mold harboring the design of microchannels. The PVA mold was embedded in PDMS and subsequently removed in water to create microchannels with 3D geometries such as dual helices and multilayer pyramidal networks. The complementary pairing of the HIPS and PVA filaments during printing facilitated the support of suspended features of the PVA mold. The PVA mold was robust and retained the original design after the exposure to limonene. The resilience of the technique demonstrated here allows us to create microchannels with geometries not attainable with sacrificial molding with a mold printed with a single material.

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Process Parameter Optimization in Fused Deposition Modeling (FDM) Using Response Surface Methodology (RSM)

10.21203/rs.3.rs-122421/v1 ◽

2020 ◽

Author(s):

Muhammad Salman Mustafa ◽

Muhammad Qasim Zafar ◽

Muhammad Arslan Muneer ◽

Muhammad Arif ◽

Farrukh Arsalan Siddiqui ◽

...

Keyword(s):

Mechanical Properties ◽

Response Surface Methodology ◽

Impact Strength ◽

Response Surface ◽

Layer Thickness ◽

Fused Deposition Modeling ◽

Experimental Results ◽

Fused Deposition ◽

Deposition Modeling ◽

Printing Parameters

Abstract Fused Deposition Modeling (FDM) is a widely adopted additive manufacturing process to produce complex 3D structures and it is typically used in the fabrication of biodegradable materials e.g. PLA/PHA for biomedical applications. However, FDM as a fabrication process for such material needs to be optimized to enhance mechanical properties. In this study, dogbone and notched samples are printed with the FDM process to determine optimum values of printing parameters for superior mechanical properties. The effect of layer thickness, infill density, and print bed temperature on mechanical properties is investigated by applying response surface methodology (RSM). Optimum printing parameters are identified for tensile and impact strength and an empirical relation has been formulated with response surface methodology (RSM). Furthermore, the analysis of variance (ANOVA) was performed on the experimental results to determine the influence of the process parameters and their interactions. ANOVA results demonstrate that 44.7% infill density, 0.44 mm layer thickness, and 20C° printing temperatures are the optimum values of printing parameters owing to improved tensile and impact strength respectively. The experimental results were found in strong agreement with the predicted theoretical results.

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Improved accuracy of an FDM 3D printer using a face-diagonal length test using an artifact and a Vernier caliper

Rapid Prototyping Journal ◽

10.1108/rpj-04-2019-0101 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Seung-Han Yang ◽

Kwang-Il Lee

Keyword(s):

Fused Deposition Modeling ◽

3D Printer ◽

Geometric Errors ◽

Content Type ◽

Fused Deposition ◽

Model Based ◽

The Face ◽

Deposition Modeling ◽

Measuring Machine ◽

Diagonal Length

Purpose The purpose of this study is to improve the accuracy of a fused deposition modeling three-dimensional (3D) printer by identifying and compensating for position-independent geometric errors using a face-diagonal length test featuring a designed artifact and a Vernier caliper. Design/methodology/approach An artifact that does not require support when printing was designed and printed to allow performance of the face-diagonal length test. A Vernier caliper was used to measure the lengths of diagonals in the XY, YZ and ZX planes of the printed artifact specimen; this completed the face-diagonal length test. The relationships between position-independent geometric errors of the linear axes X, Y and Z and the measured diagonal lengths of the three planes were determined to identify geometric errors. Findings The approach was applied to a commercial fused deposition modeling 3D printer, and three position-independent geometric errors were rapidly identified. The artifact was re-printed after model-based compensation for these errors and the diagonal lengths were re-measured. The results were verified via coordinate measuring machine measurement of a simple test piece without and with model-based compensation for identified geometric errors. Furthermore, the proposed approach was applied to a commercial 3D printer. Research limitations/implications The measured diagonal lengths of the printed artifacts varied greatly. Thus, further studies should investigate the effects of printing materials and parameters on the length discrepancies of 3D printed artifacts. Practical implications A software-based compensation of identified position-independent geometric errors has to be used at commercial 3D printers for accuracy improvements of printed parts. Originality/value Thus, the approach is of practical utility; it can be periodically used to identify position-independent geometric errors and ensure that the 3D printer is consistently accurate.

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