scholarly journals On the use of nano fibrillated kenaf cellulose fiber as reinforcement in polylactic acid biocomposites

2019 ◽  
Vol 13 (2) ◽  
pp. 4970-4988 ◽  
Author(s):  
Q. Ahsan ◽  
T. S. S. Carron ◽  
Z. Mustafa
Keyword(s):  
Tensile Strength ◽  
Average Length ◽  
Synergistic Effects ◽  
Cellulose Fiber ◽  
Optical Microscope ◽  
Morphological Properties ◽  
Poly Lactic Acid ◽  
Maximum Increase ◽  
New Strategy ◽  
Mechanical Fibrillation

In this study, nano fibrillated kenaf cellulose (NFKC) derived from kenaf fiber after varying chemico-mechanical treatments were introduced into poly lactic acid (PLA) as reinforcements to improve the mechanical and morphological properties of the biocomposites. The new strategy was aiming to realize the synergistic effects of chemical treatment and mechanical fibrillation process parameters (blending speed and time) for yielding nano fibers and its reinforcement effects on the properties of biocomposites. The yield percentage of the NFKC was determined using centrifugal method and the NFKC fibers with PLA pellet were hot pressed to form NFKC-PLA composites. The distribution and dispersion morphologies of NFKC in NFKC-PLA composites were observed by using optical microscope (OM) and scanning electron microscope (SEM). The reinforcing effect on the mechanical properties of NFKC-PLA composite was investigated by tensile strength test. Average length and diameter of fibrillated fibers were decreased with the concurrent increase of blending speed and time. The maximum increase in tensile strength of 59.32% and elongation of 100% were observed for NFKC-PLA composite with NFKC yielded at a blending speed and time of 15000 rpm and 15 minutes as compared to pure PLA. The tensile properties indicated that the strength and modulus were improved with increased nanofiber contents.

scholarly journals Thermo-Mechanical and Morphological Properties of Polymer Composites Reinforced by Natural Fibers Derived from Wet Blue Leather Wastes: A Comparative Study

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1837
Author(s):  
Alessandro Nanni ◽  
Mariafederica Parisi ◽  
Martino Colonna ◽  
Massimo Messori
Keyword(s):  
Tensile Strength ◽  
Polymer Matrix ◽  
Thermoplastic Polyurethane ◽  
Young Modulus ◽  
Morphological Properties ◽  
Poly Lactic Acid ◽  
Matrix Adhesion ◽  
The Poor ◽  
Leather Wastes ◽  
Fiber Matrix

The present work investigated the possibility to use wet blue (WB) leather wastes as natural reinforcing fibers within different polymer matrices. After their preparation and characterization, WB fibers were melt-mixed at 10 wt.% with poly(lactic acid) (PLA), polyamide 12 (PA12), thermoplastic elastomer (TPE), and thermoplastic polyurethane (TPU), and the obtained samples were subjected to rheological, thermal, thermo-mechanical, and viscoelastic analyses. In parallel, morphological properties such as fiber distribution and dispersion, fiber–matrix adhesion, and fiber exfoliation phenomena were analyzed through a scanning electron microscope (SEM) and energy-dispersive spectroscopy (EDS) to evaluate the relationship between the compounding process, mechanical responses, and morphological parameters. The PLA-based composite exhibited the best results since the Young modulus (+18%), tensile strength (+1.5%), impact (+10%), and creep (+5%) resistance were simultaneously enhanced by the addition of WB fibers, which were well dispersed and distributed in and significantly branched and interlocked with the polymer matrix. PA12- and TPU-based formulations showed a positive behavior (around +47% of the Young modulus and +40% of creep resistance) even if the not-optimal fiber–matrix adhesion and/or the poor de-fibration of WB slightly lowered the tensile strength and elongation at break. Finally, the TPE-based sample exhibited the worst performance because of the poor affinity between hydrophilic WB fibers and the hydrophobic polymer matrix.

scholarly journals Crazing Effect on the Bio-Based Conducting Polymer Film

Polymers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 3425
Author(s):  
Pei-Yi Wong ◽  
Akiyoshi Takeno ◽  
Shinya Takahashi ◽  
Sook-Wai Phang ◽  
Azizah Baharum
Keyword(s):  
Weight Loss ◽  
Tensile Strength ◽  
Polymer Film ◽  
Polymer Chain ◽  
Tensile Strain ◽  
Young Modulus ◽  
Optical Microscope ◽  
Poly Lactic Acid ◽  
Pani Film ◽  
Polymer Waste

The biodegradability problem of polymer waste is one of the fatal pollutFions to the environment. Enzymes play an essential role in increasing the biodegradability of polymers. In a previous study, antistatic polymer film based on poly(lactic acid) (PLA) as a matrix and polyaniline (PAni) as a conductive filler, was prepared. To solve the problem of polymer wastes pollution, a crazing technique was applied to the prepared polymer film (PLA/PAni) to enhance the action of enzymes in the biodegradation of polymer. This research studied the biodegradation test based on crazed and non-crazed PLA/PAni films by enzymes. The presence of crazes in PLA/PAni film was evaluated using an optical microscope and scanning electron microscopy (SEM). The optical microscope displayed the crazed in the lamellae form, while the SEM image revealed microcracks in the fibrils form. Meanwhile, the tensile strength of the crazed PLA/PAni film was recorded as 19.25 MPa, which is almost comparable to the original PLA/PAni film with a tensile strength of 20.02 MPa. However, the Young modulus decreased progressively from 1113 MPa for PLA/PAni to 651 MPa for crazed PLA/PAni film, while the tensile strain increased 150% after crazing. The significant decrement in the Young modulus and increment in the tensile strain was due to the craze propagation. The entanglement was reduced and the chain mobility along the polymer chain increased, thus leading to lower resistance to deformation of the polymer chain and becoming more flexible. The presence of crazes in PLA/PAni film showed a substantial change in weight loss with increasing the time of degradation. The weight loss of crazed PLA/PAni film increased to 42%, higher than that of non-crazed PLA/PAni film with only 31%. The nucleation of crazes increases the fragmentation and depolymerization of PLA/PAni film that induced microbial attack and led to higher weight loss. In conclusion, the presence of crazes in PLA/PAni film significantly improved enzymes’ action, speeding up the polymer film’s biodegradability.

The Study of Using Bio-Filler from Cassava Pulp in Natural Rubber Composites

2013 ◽  
Vol 747 ◽  
pp. 371-374 ◽  
Author(s):  
Watcharin Ruangudomsakul ◽  
Chaiwat Ruksakulpiwat ◽  
Ruksakulpiwat Yupaporn
Keyword(s):  
Tensile Strength ◽  
Natural Rubber ◽  
Cellulose Fiber ◽  
Cassava Starch ◽  
Morphological Properties ◽  
Rubber Composites ◽  
Elongation At Break ◽  
Cassava Pulp ◽  
Natural Rubber Composites ◽  
Properties Of Composites

Cassava pulp (CP) is an inexpensive and broadly available waste by-product from cassava starch production. This by-product is basically constituted of cellulose fiber and residual starch. In this study, cassava pulp was mixed with natural rubber (NR) with various contents using two roll mills to obtain CP/NR composites. Natural rubber grafted glycidyl methacrylate (NR-g-GMA) was used as compatibilizer in CP/NR/NR-g-GMA composites. Sulfur conventional vulcanization was used. The composite specimens were prepared by compression molding. Mechanical properties and morphological properties of composites were investigated. The results showed that tensile strength was significantly increased with increasing content of cassava pulp up to 20 phr. However, when cassava pulp was increased more than 30 phr, tensile strength was slightly decreased. Elongation at break of NR composites was not changed with increasing cassava pulp. The modulus of NR composites was increased with increasing cassava pulp content. Morphological properties of CP/NR composites was elucidated as well.

Jute Fiber Reinforced Thermoplastic Composites Fabricated by Direct Fiber Feeding Injection Molding (DFFIM) Process

2020 ◽  
Vol 856 ◽  
pp. 268-275
Author(s):  
Prattakon Sarasook ◽  
Putinun Uawongsuwan ◽  
Anin Memon ◽  
Hiroyuki Hamada
Keyword(s):  
Tensile Strength ◽  
Injection Molding ◽  
Tensile Modulus ◽  
Jute Fiber ◽  
Morphological Properties ◽  
Thermoplastic Composites ◽  
Poly Lactic Acid ◽  
Fiber Reinforced ◽  
Molding Process ◽  
Spun Yarns

In this research, jute fiber reinforced polypropylene and poly (lactic acid) composites were fabricated, respectively by Direct Fiber Feeding Injection molding (DFFIM) process. Jute spun yarns were directly fed into the barrel of molding process in order to eliminate the fiber breakage during extrusion compounding process. Mechanical properties of both composites were investigated by tensile testing and morphological properties were characterized by scanning electron microscopy (SEM). For jute reinforced polypropylene (PP) composites, tensile strength of composite decreased but modulus increased, compared with neat PP. The using maleic anhydride grafted polypropylene (MaPP) can improve interfacial bonding between jute fiber and PP matrix as observed by SEM, which resulted in the increasing of tensile strength. Therefore, in the case of jute/PLA composites, jute fibers surface treated with sodium hydroxide (NaOH) and silane coupling agent to improve interfacial adhesion. The tensile strength of untreated-jute/PLA composites are not different with PLA matrix but tensile modulus of untreated composites are higher than PLA matrix. In addition it is found that the tensile properties of NaOH-treated jute/PLA and NaOH+Silane-treated jute/PLA composites were improved, compared with untreated composites.

Properties of HDPE/Biodegradable Polymer Blends Using Modified Rubber

2017 ◽  
Vol 873 ◽  
pp. 101-106 ◽  
Author(s):  
Chanon Wiphanurat ◽  
Pran Hanthanon ◽  
Thiti Kaisone ◽  
Rathanawan Magaraphan ◽  
Tarinee Nampitch
Keyword(s):  
Tensile Strength ◽  
Polymer Blends ◽  
Biodegradable Polymer ◽  
Tensile Tests ◽  
Morphological Properties ◽  
Poly Lactic Acid ◽  
High Tensile Strength ◽  
Elongation At Break ◽  
Compatibilization Effect ◽  
Scanning Electron

Biodegradable blends consisting of poly(lactic acid) (PLA), poly(butylene adipate-coterephthalate) (PBAT) and epoxidized natural rubber (ENR) were blended in two proportions at PLA/PBAT/ENR ratios of 70/10/20 and 70/20/10. Then, blends these biodegradable polymers (PLA/PBAT/ENR) with HDPE at various ratios of 20/80, 10/90 and 5/95 wt%, the mechanical and morphological properties were investigated. Tensile tests of PLA/PBAT/ENR blends revealed high tensile strength and modulus but low elongation compared with HDPE. The tensile strength, elongation at break and impact strength of HDPE/biodegradable polymer blends decreased with increasing biodegradable polymer contents. Morphological properties of HDPE/biodegradable polymer blends were investigated by scanning electron microscope, which showed smoother surface of HDPE/biodegradable (70/10/20) than those of (70/20/10) polymer blends according to ENR compatibilization effect.

Morphology of High-Performance Rigid-Rod Polymer Fibers and Molecular Composites

1989 ◽  
Vol 47 ◽  
pp. 338-339
Author(s):  
W.W. Adams ◽  
S. J. Krause
Keyword(s):  
Tensile Strength ◽  
High Performance ◽  
Liquid Crystalline ◽  
Molecular Level ◽  
Synergistic Effects ◽  
Tensile Modulus ◽  
Commercial Development ◽  
The Matrix ◽  
Molecular Composites ◽  
Rigid Rod

Rigid-rod polymers such as PBO, poly(paraphenylene benzobisoxazole), Figure 1a, are now in commercial development for use as high-performance fibers and for reinforcement at the molecular level in molecular composites. Spinning of liquid crystalline polyphosphoric acid solutions of PBO, followed by washing, drying, and tension heat treatment produces fibers which have the following properties: density of 1.59 g/cm3; tensile strength of 820 kpsi; tensile modulus of 52 Mpsi; compressive strength of 50 kpsi; they are electrically insulating; they do not absorb moisture; and they are insensitive to radiation, including ultraviolet. Since the chain modulus of PBO is estimated to be 730 GPa, the high stiffness also affords the opportunity to reinforce a flexible coil polymer at the molecular level, in analogy to a chopped fiber reinforced composite. The objectives of the molecular composite concept are to eliminate the thermal expansion coefficient mismatch between the fiber and the matrix, as occurs in conventional composites, to eliminate the interface between the fiber and the matrix, and, hopefully, to obtain synergistic effects from the exceptional stiffness of the rigid-rod molecule. These expectations have been confirmed in the case of blending rigid-rod PBZT, poly(paraphenylene benzobisthiazole), Figure 1b, with stiff-chain ABPBI, poly 2,5(6) benzimidazole, Fig. 1c A film with 30% PBZT/70% ABPBI had tensile strength 190 kpsi and tensile modulus of 13 Mpsi when solution spun from a 3% methane sulfonic acid solution into a film. The modulus, as predicted by rule of mixtures, for a film with this composition and with planar isotropic orientation, should be 16 Mpsi. The experimental value is 80% of the theoretical value indicating that the concept of a molecular composite is valid.

Analysis of Sound Reduction and Strong Drag Composite Concrete Fibers Gedebok Banana Results Delignification with Sodium Hydroxide Solvent (Naoh)

2018 ◽  
Vol 6 (02) ◽  
pp. 105-120
Author(s):  
Muhammad Rouf Suprayogi ◽  
Annisa Mufida ◽  
Edwin Azwar
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Lignin Content ◽  
Sound Intensity ◽  
Cellulose Fiber ◽  
Cellulose Content ◽  
Cellulose Powder ◽  
Drying Method ◽  
Normal Concrete ◽  
Sound Reduction

In composite science, desirable materials that are lighter but have the power and quality that can match or even exceed the material that has been there before. The purpose of this study was to investigate the effect of cellulose fiber addition from banana gedebok to tensile strength, compressive strength and damping of concrete composite sound. To achieve this objective, mixing of cellulose fibers with K-275 quality concrete mix with variation of 0% and 5% substitution in which the cellulose is varied in powder and wicker form. Delignification of lignin content from banana gedebok was done by soaking and drying method without any variation and yielding powder having cellulose content of 13,0388%, hemicellulose 18,2796% and lignin 0,6684%. This study produces concrete composites that have a tensile strength and a compressive strength lower than that of normal concrete. Normally reinforced concrete tensile strength value 94.5 kg / cm2, 71.4 kg / cm2 cellulose powder concrete and 90.3 kg / cm2 cellulose woven concrete. Normal concrete compressive strength value 334,22 kg / cm2, cellulose powder concrete 215,7 kg / cm2, and cellulose webbing concrete 157,98 kg / cm2. As for the power damping sound of cellulose webbing concrete has the highest damping power compared to other concrete with the absorbed sound intensity that is 52-68 dB

Effect of Polyethylene Glycol in Nanocellulose/PLA Composites

2019 ◽  
Vol 821 ◽  
pp. 89-95
Author(s):  
Wanasorn Somphol ◽  
Thipjak Na Lampang ◽  
Paweena Prapainainar ◽  
Pongdhorn Sae-Oui ◽  
Surapich Loykulnant ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Lactic Acid ◽  
Polyethylene Glycol ◽  
Aspect Ratio ◽  
Mechanical Performance ◽  
Tensile Modulus ◽  
Poly Lactic Acid ◽  
Solvent Casting ◽  
Casting Method ◽  
Mediated Oxidation

Poly (lactic acid) or PLA was reinforced by nanocellulose and polyethylene glycol (PEG), which were introduced into PLA matrix from 0 to 3 wt.% to enhance compatibility and strength of the PLA. The nanocellulose was prepared by TEMPO-mediated oxidation from microcrystalline cellulose (MCC) powder and characterized by TEM, AFM, and XRD to reveal rod-like shaped nanocellulose with nanosized dimensions, high aspect ratio and high crystallinity. Films of nanocellulose/PEG/PLA nanocomposites were prepared by solvent casting method to evaluate the mechanical performance. It was found that the addition of PEG in nanocellulose-containing PLA films resulted in an increase in tensile modulus with only 1 wt% of PEG, where higher PEG concentrations negatively impacted the tensile strength. Furthermore, the tensile strength and modulus of nanocellulose/PEG/PLA nanocomposites were higher than the PLA/PEG composites due to the existence of nanocellulose chains. Visual traces of crazing were detailed to describe the deformation mechanism.

scholarly journals Study on the Dissolution and Precipitation Behavior of Self-Designed (NbTi)C Nanoparticles Addition in 1045 Steel

Metals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 184
Author(s):  
Hongwei Zhu ◽  
Haonan Li ◽  
Furen Xiao ◽  
Zhixiang Gao
Keyword(s):  
Tensile Strength ◽  
Electron Microscope ◽  
Optical Microscope ◽  
Cast Steels ◽  
Uniform Dispersion ◽  
The Matrix ◽  
Thermo Calc Software ◽  
Particle Strengthening ◽  
1045 Steel ◽  
Addition Amount

Self-designed (NbTi)C nanoparticles were obtained by mechanical alloying, predispersed in Fe powder, and then added to 1045 steel to obtain modified cast steels. The microstructure of cast steels was investigated by an optical microscope, scanning electron microscope, X-ray diffraction, and a transmission electron microscope. The results showed that (NbTi)C particles can be added to steels and occur in the following forms: original ellipsoidal morphology nanoparticles with uniform dispersion in the matrix, cuboidal nanoparticles in the grain, and microparticles in the grain boundary. Calculations by Thermo-Calc software and solubility formula show that cuboidal (NbTi)C nanoparticles were precipitated in the grain, while the (NbTi)C microparticles were formed by eutectic transformation. The results of the tensile strength of steels show that the strength of modified steels increased and then declined with the increase in the addition amount. When the addition amount was 0.16 wt.%, the modified steel obtained the maximum tensile strength of 759.0 MPa, which is an increase of 52% compared with to that with no addition. The hardness of the modified steel increased with the addition of (NbTi)C nanoparticles. The performance increase was mainly related to grain refinement and the particle strengthening of (NbTi)C nanoparticles, and the performance degradation was related to the increase in eutectic (NbTi)C.

scholarly journals Biocomposites of Epoxidized Natural Rubber/Poly(lactic acid) Modified with Natural Fillers (Part I)

2021 ◽  
Vol 22 (6) ◽  
pp. 3150
Author(s):  
Anna Masek ◽  
Stefan Cichosz ◽  
Małgorzata Piotrowska
Keyword(s):  
Tensile Strength ◽  
Lactic Acid ◽  
Natural Rubber ◽  
Epoxidized Natural Rubber ◽  
Poly Lactic Acid ◽  
Uv Aging ◽  
High Elasticity ◽  
Natural Fillers ◽  
Natural Additives

The study aimed to prepare sustainable and degradable elastic blends of epoxidized natural rubber (ENR) with poly(lactic acid) (PLA) that were reinforced with flax fiber (FF) and montmorillonite (MMT), simultaneously filling the gap in the literature regarding the PLA-containing polymer blends filled with natural additives. The performed study reveals that FF incorporation into ENR/PLA blend may cause a significant improvement in tensile strength from (10 ± 1) MPa for the reference material to (19 ± 2) MPa for the fibers-filled blend. Additionally, it was found that MMT employment in the role of the filler might contribute to ENR/PLA plasticization and considerably promote the blend elongation up to 600%. This proves the successful creation of the unique and eco-friendly PLA-containing polymer blend exhibiting high elasticity. Moreover, thanks to the performed accelerated thermo-oxidative and ultraviolet (UV) aging, it was established that MMT incorporation may delay the degradation of ENR/PLA blends under the abovementioned conditions. Additionally, mold tests revealed that plant-derived fiber addition might highly enhance the ENR/PLA blend’s biodeterioration potential enabling faster and more efficient growth of microorganisms. Therefore, materials presented in this research may become competitive and eco-friendly alternatives to commonly utilized petro-based polymeric products.

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