Analysis of Mechanical Properties in Thermoplastic Polyurethane-Microcrystalline Cellulose Composites

Polymer Korea ◽  
2020 ◽  
Vol 44 (6) ◽  
pp. 776-783
Author(s):  
Yongju Kim ◽  
Hyeok Jun Yoon ◽  
Sang Yeon Lee ◽  
Jong Hyeok Lee ◽  
Seong Bak Moon ◽  
...  
2015 ◽  
Vol 1115 ◽  
pp. 402-405
Author(s):  
Noorasikin Samat ◽  
N. Zulkapli ◽  
Zahurin Halim ◽  
Zuraida Ahmad ◽  
A.I.H.Dayang Habibah

The mechanical and flame properties of polypropylene/ microcrystalline cellulose (MCC) composites containing different loading of aluminium hydroxide (ATH) nanoparticles from 3 to 20wt% was studied. Maleic anhydride grafted polypropylene (MAPP) was used as a coupling agent in the composites. The mechanical properties of PP/MCC composites were characterized by tensile and impact tests while the flame properties were evaluated by UL-94 and oxygen index tests. It was shown that the addition of ATH improved the mechanical and flame resistance properties PP/MCC composites, mainly in the composites with MAPP. Fracture surface observations in samples with MAPP show better dispersion and adhesion of fillers (MCC and ATH). Flame retardancy also enhanced along with the ATH loading.


2021 ◽  
Vol 1041 ◽  
pp. 3-9
Author(s):  
Cyron L. Custodio ◽  
Joel M. Cabañero ◽  
Marissa A. Paglicawan ◽  
Blessie A. Basilia

In an attempt to improve the physical properties of 3D printed poly lactic acid (PLA), this study aims to develop a microcrystalline cellulose fiber and observe the effects of fiber loading on the PLA/cellulose composites to the composition, crystallinity, morphology, and tensile properties of the resulting 3D printed material. Microcrystalline cellulose (MCC) have been extracted from indigenous raw abaca fibers and used as the fiber reinforcement for the PLA matrix. Composites of 1 and 3 wt% MCC fibers with PLA were processed using the twin-screw extruder to produce filaments. The resulting composite filaments were 3D printed utilizing the fused deposition modeling technology. FTIR, XRD, digital microscopy, and mechanical testing were used in characterizing the various 3D printed PLA/MCC composite. With the incorporation of cellulose, the PLA/MCC had up to 32% increase in tensile strength and 43% increase in modulus at just 3 wt% fiber loading due to the inherent high modulus of abaca cellulose. The MCC significantly influences the chemical, structural and mechanical properties of the 3D printed PLA/MCC composites.


Polymer Korea ◽  
2021 ◽  
Vol 45 (2) ◽  
pp. 236-245
Author(s):  
Jae Gyeong Lee ◽  
Yongju Kim ◽  
Young Dong Lee ◽  
Hyeok Jun Yoon ◽  
Jeong Eun Park ◽  
...  

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2460
Author(s):  
Jacob Abdelfatah ◽  
Rubén Paz ◽  
María Elena Alemán-Domínguez ◽  
Mario Monzón ◽  
Ricardo Donate ◽  
...  

The degradation rate of polycaprolactone (PCL) is a key issue when using this material in Tissue Engineering or eco-friendly packaging sectors. Although different PCL-based composite materials have been suggested in the literature and extensively tested in terms of processability by material extrusion additive manufacturing, little attention has been paid to the influence of the fillers on the mechanical properties of the material during degradation. This work analyses the possibility of tuning the degradation rate of PCL-based filaments by the introduction of microcrystalline cellulose into the polymer matrix. The enzymatic degradation of the composite and pure PCL materials were compared in terms of mass loss, mechanical properties, morphology and infrared spectra. The results showed an increased degradation rate of the composite material due to the presence of the filler (enhanced interaction with the enzymes). Additionally, a new numerical method for the prediction of the degraded geometry was developed. The method, based on the Monte Carlo Method in an iterative process, adjusts the degradation probability according to the exposure of each discretized element to the degradation media. This probability is also amplified depending on the corresponding experimental mass loss, thus allowing a good fit to the experimental data in relatively few iterations.


2020 ◽  
Vol 90 (21-22) ◽  
pp. 2399-2410 ◽  
Author(s):  
Shahbaj Kabir ◽  
Hyelim Kim ◽  
Sunhee Lee

This study has investigated the physical properties of 3D-printable shape memory thermoplastic polyurethane (SMTPU) filament and its 3D-printed sinusoidal pattern obtained by fused deposition modeling (FDM) technology. To investigate 3D filaments, thermoplastic polyurethane (TPU) and SMTPU filament were examined by conducting infrared spectroscopy, x-ray diffraction (XRD), dynamic mechanical thermal analysis (DMTA), differential scanning calorimetry (DSC) and a tensile test. Then, to examine the 3D-printed sinusoidal samples, a sinusoidal pattern was developed and 3D-printed. Those samples went through a three-step heating process: (a) untreated state; (b) 5 min heating at 70°C, cooling for 30 min at room temperature; and (c) a repeat of step 2. The results obtained by the three different heating processes of the 3D-printed sinusoidal samples were examined by XRD, DMTA, DSC and the tensile test to obtain the effect of heating or annealing on the structural and mechanical properties. The results show significant changes in structure, crystallinity and thermal and mechanical properties of SMTPU 3D-printed samples due to the heating steps. XRD showed the increase in crystallinity with heating. In DMTA, storage modulus, loss modulus and the tan σ peak position also changed for various heating steps. The DSC result showed that the Tg for different steps of the SMTPU 3D-printed sample remained almost the same at around 51°C. The tensile property of the TPU 3D-printed sinusoidal sample decreased in terms of both load and elongation with increased heating processes, while for the SMTPU 3D-printed sinusoidal sample, the load decreased but elongation increased about 2.5 times.


2021 ◽  
pp. 002199832110370
Author(s):  
Chia-Fang Lee ◽  
Chin-Wen Chen ◽  
Fu-Sheng Chuang ◽  
Syang-Peng Rwei

Multi-wall carbon nanotubes (MWCNTs) at 0.5 wt% to 2 wt% proportions were added to thermoplastic polyurethane (TPU) synthesized with polycarbonatediol (PCDL), 4,4’-methylene diphenyl diisocyanate (MDI), and 1,3-butanediol(1,3-BDO). To formulate a new TPU-MWCNT nanocomposite, the composite was melt-blended with a twin-screw extruder. To ensure the even dispersion of MWCNTs, dispersant (ethylene acrylic ester terpolymer; Lotader AX8900) of equal weight proportion to the added MWCNTs was also added during the blending process. Studies on the mechanical and thermal properties, and melt flow experiments and phase analysis of TPU-MWCNT nanocomposites, these nanocomposites exhibit higher tensile strength and elongation at break than neat TPU. TPU-MWCNT nanocomposites with higher MWCNT content possess higher glass-transition temperature (Tg), a lower melt index, and greater hardness. Relative to neat TPU, TPU-MWCNT nanocomposites exhibit favorable mechanical properties. By adding MWCNTs, the tensile strength of the nanocomposites increased from 7.59 MPa to 21.52 MPa, and Shore A hardness increased from 65 to 81. Additionally, TPU-MWCNT nanocomposites with MWCNTs had lower resistance coefficients; the resistance coefficient decreased from 4.97 × 1011 Ω/sq to 2.53 × 104 Ω/sq after adding MWCNTs, indicating a conductive polymer material. Finally, the internal structure of the TPU-MWCNT nanocomposites was examined under transmission electron microscopy. When 1.5 wt% or 2 wt% of MWCNTs and dispersant were added to TPU, the MWCNTs were evenly dispersed, with increased electrical conductivity and mechanical properties. The new material is applicable in the electronics industry as a conductive polymer with high stiffness.


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