Effect of Processing Temperature and the Content of Carbon Nanotubes on the Properties of Nanocomposites Based on Polyphenylene Sulfide

The study aimed to investigate the effect of processing temperature and the content of multi-wall carbon nanotubes (MWCNTs) on the rheological, thermal, and electrical properties of polyphenylene sulfide (PPS)/MWCNT nanocomposites. It was observed that the increase in MWCNT content influenced the increase of the complex viscosity, storage modulus, and loss modulus. The microscopic observations showed that with an increase in the amount of MWCNTs, the areal ratio of their agglomerates decreases. Thermogravimetric analysis showed no effect of processing temperature and MWCNT content on thermal stability; however, an increase in stability was observed as compared to neat PPS. The differential scanning calorimetry was used to assess the influence of MWCNT addition on the crystallization phenomenon of PPS. The calorimetry showed that with increasing MWCNT content, the degree of crystallinity and crystallization temperature rises. Thermal diffusivity tests proved that with an increase in the processing temperature and the content of MWCNTs, the diffusivity also increases and declines at higher testing temperatures. The resistivity measurements showed that the conductivity of the PPS/MWCNT nanocomposite increases with the increase in MWCNT content. The processing temperature did not affect resistivity.

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Non-Isothermal Crystallization Kinetics of Injection Grade PHBV and PHBV/Carbon Nanotubes Nanocomposites Using Isoconversional Method

Journal of Composites Science ◽

10.3390/jcs4020052 ◽

2020 ◽

Vol 4 (2) ◽

pp. 52

Author(s):

Thaís Larissa do Amaral Montanheiro ◽

Beatriz Rossi Canuto de Menezes ◽

Larissa Stieven Montagna ◽

Cesar Augusto Gonçalves Beatrice ◽

Juliano Marini ◽

...

Keyword(s):

Carbon Nanotubes ◽

Crystallization Kinetics ◽

Isothermal Crystallization ◽

Model Fitting ◽

Polarized Light ◽

Isoconversional Method ◽

Degree Of Crystallinity ◽

Gamma Aminobutyric Acid ◽

Scanning Calorimetry ◽

Kinetics Of

Carbon nanotubes (CNT)-reinforced polymeric composites are being studied as promising materials due to their enhanced properties. However, understanding the behavior of polymers during non-isothermal crystallization is important once the degree of crystallinity and crystallization processes are affected when nanoparticles are added to matrices. Usually, crystallization kinetics studies are performed using a model-fitting method, though the isoconversional method allows to obtain the kinetics parameter without assuming a crystallization model. Therefore, in this work, CNTs were oxidized (CNT-Ox) and functionalized with gamma-aminobutyric acid (GABA) (CNT-GB) and incorporated into a poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) matrix. The influence of the addition and functionalization of CNT in the crystallization kinetics of PHBV was evaluated using the isoconversional method with differential scanning calorimetry (DSC), and by polarized light optical microscopy (PLOM) and Shore D hardness. The incorporation and functionalization of CNT into PHBV matrix did not change the Šesták and Berggren crystallization model; however, the lowest activation energy was obtained for the composite produced with CNT-GB, suggesting a better dispersion into the PHBV matrix. PLOM and Shore D hardness confirmed the results obtained in the kinetics study, showing the smallest crystallite size for CNT-containing nanocomposites and the highest hardness value for the composite produced with CNT-GB.

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Crystallization Processes In Poly (Ethylene Terephthalate) / Polycarbonate Blends

MRS Proceedings ◽

10.1557/proc-321-543 ◽

1993 ◽

Vol 321 ◽

Author(s):

Veronika E. Reinsch ◽

Ludwig Rebenfeld

Keyword(s):

Ethylene Terephthalate ◽

Crystallization Rate ◽

Melt Processing ◽

Degree Of Crystallinity ◽

Processing Temperature ◽

Scanning Calorimetry ◽

Processing Times ◽

Poly Ethylene Terephthalate ◽

Poly Ethylene ◽

Crystallization From The Melt

ABSTRACTBlends of poly (ethylene terephthalate), or PET, and polycarbonate (PC) over a range of compositions were studied in isothermal crystallizations from the melt using differential scanning calorimetry (DSC). Both crystallization rate and degree of crystallinity of PET depend on blend composition. The glass transition temperature, Tg, of PET and PC in blends and pure polymer were also measured by DSC. Elevation of the Tg of PET and depression of the Tg of PC are observed upon blending. In cooling scans, dynamic crystallization from the melt was observed. In PET/PC blends with high PC content, a novel dual-peak crystallization of PET was observed. The effects of thermal history on crystallization kinetics and degree of crystallinity were also determined in isothermal crystallization studies. For Melt processing times between 1 and 30 Min and for processing temperatures between 280 and 300 °C, Melt processing temperature was seen to have a stronger effect than processing time.

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EVALUATION OF A HYBRID BIOCOMPOSITE OF HA/HDPE REINFORCED WITH MULTI-WALLED CARBON NANOTUBES (MWCNTs) AS A BONE-SUBSTITUTE MATERIAL

Materiali in tehnologije ◽

10.17222/mit.2021.162 ◽

2021 ◽

Vol 55 (5) ◽

Author(s):

Ali A. Al- Allaq ◽

Jenan S. Kashan ◽

Mohamed T. El-Wakad ◽

Ahmed M. Soliman

Keyword(s):

Carbon Nanotubes ◽

Bone Substitute ◽

Ringer Solution ◽

Degree Of Crystallinity ◽

Crystallographic Structure ◽

Hot Press ◽

Multi Wall Carbon Nanotubes ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

In this investigation, multi-wall carbon nanotubes (MWCNT) with various percentages (0.6%, 1%, 1.4%, 2%) were combined into and High-density polyethylene HDPE (60) wt. % and hydroxyapatite (40) wt. % to form biocomposite using hot-press techniques. The surface topography by AFM images illustrates differences in the roughness of the sample's surface with different adding percentages of MWCNT. The DSC technique exhibits the effect of adding MWCNT in different percentages with the degree of crystallinity, which its effect on mechanical properties for samples. The in vitro bioactivity was investigated by immersion the samples in Ringer's solution as simulated body fluid (SBF) at (0, 3, 6, 9, 12) days (after immersing). The FE-SEM and EDx image explained the apatite layers formation on the sample's surface after 3 days immersed in Ringer solution. Based on XRD Technique, after immersion days in the Ringer solution, the crystallographic structure of hydroxyapatite is formed, forming the monetite. The enhancement of bioactivity has been shown during the incorporation of MWCNT into HA/HDPE composite. These results exhibited excellent indications of biocompatibility properties with the possibility of making promising biomaterials for making bone substitute applications.

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Effect of Extrusion Screw Speed and Plasticizer Proportions on the Rheological, Thermal, Mechanical, Morphological and Superficial Properties of PLA

Polymers ◽

10.3390/polym12092111 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2111

Author(s):

Jaime Gálvez ◽

Juan Correa Aguirre ◽

Miguel Hidalgo Salazar ◽

Bairo Vera Mondragón ◽

Elizabeth Wagner ◽

...

Keyword(s):

Loss Modulus ◽

Complex Viscosity ◽

Processing Parameters ◽

Extrusion Process ◽

Mechanical Analysis ◽

Residual Energy ◽

Poly Lactic Acid ◽

Scanning Calorimetry ◽

Rheological Analysis ◽

Acetyl Tributyl Citrate

One of the critical processing parameters—the speed of the extrusion process for plasticized poly (lactic acid) (PLA)—was investigated in the presence of acetyl tributyl citrate (ATBC) as plasticizer. The mixtures were obtained by varying the content of plasticizer (ATBC, 10–30% by weight), using a twin screw extruder as a processing medium for which a temperature profile with peak was established that ended at 160 °C, two mixing zones and different screw rotation speeds (60 and 150 rpm). To evaluate the thermo-mechanical properties of the blend and hydrophilicity, the miscibility of the plasticizing and PLA matrix, Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), oscillatory rheological analysis, Dynamic Mechanical Analysis (DMA), mechanical analysis, as well as the contact angle were tested. The results derived from the oscillatory rheological analysis had a viscous behavior in the PLA samples with the presence of ATBC; the lower process speed promotes the transitions from viscous to elastic as well as higher values of loss modulus, storage modulus and complex viscosity, which means less loss of molecular weight and lower residual energy in the transition from the viscous state to the elastic state. The mechanical and thermal performance was optimized considering a greater capacity in the energy absorption and integration of the components.

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Role of Multiwalled Carbon Nanotube on Mechanical Reinforcement of High-Density Polyethylene

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.652-654.15 ◽

2013 ◽

Vol 652-654 ◽

pp. 15-24 ◽

Cited By ~ 2

Author(s):

Xia Ran Miao ◽

Yuan Jiang Qi ◽

Xiao Yun Li ◽

Yu Zhu Wang ◽

Xiao Long Li ◽

...

Keyword(s):

Mechanical Properties ◽

Carbon Nanotubes ◽

High Density Polyethylene ◽

High Density ◽

Scanning Calorimetry ◽

Melt Mixing ◽

Multiwalled Carbon ◽

Mechanical Reinforcement ◽

Multi Wall Carbon Nanotubes ◽

X Ray Scattering

The high density polyethylene (HDPE) nanocomposites were prepared by melt mixing HDPE with multi-wall carbon nanotubes (MWCNTs). In this work, the morphological, nucleation, crystallization and mechanical properties of the HDPE nanocomposites were studied by scanning electron microscopy, different scanning calorimetry, small-angle X-ray scattering and tensile testing. It was found that the tensile strength and Young’s modulus is increased by 42.4% and 116.5% at 3.wt% MWCNT loading compared to the pure HDPE. According to SEM results combined with SAXS, well-defined nanohybird shish-kebab (NHSK) entities exist in the composites, and in the shish-kebab structures fibrillous carbon nanotubes (MWCNTs) act as shish while HDPE lamellae act as kebab. The crystallization behavior, probed by DSC, suggests that MWCNTs have strong nucleation ability and shear stress plays an important role in polymer crystallization process. The mechanical properties demonstrated that the formation of the Shish-kebab structures improved the interfacial adhesion and brought obvious mechanical enhancement for the HDPE/MWCNTs nanocomposites.

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Crystallization and mechanical properties of polyphenylene sulfide/multiwalled carbon nanotube composites

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705717738303 ◽

2017 ◽

Vol 31 (11) ◽

pp. 1545-1560 ◽

Cited By ~ 3

Author(s):

Rui Yang ◽

Zhengtao Su ◽

Shan Wang ◽

Yanfen Zhao ◽

Jiao Shi

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Carbon Nanotube ◽

Polyphenylene Sulfide ◽

Multiwalled Carbon Nanotube ◽

Degree Of Crystallinity ◽

Multiwalled Carbon ◽

Mwcnt Content ◽

Transmission Electron ◽

Nanotube Composites

Polyphenylene sulfide (PPS)/multiwalled carbon nanotube (MWCNT) composites were prepared by melt blending and injection molding. The nonisothermal crystallization behavior, morphology, and mechanical properties of the nanocomposites were systematically investigated as a function of MWCNT content. For nonisothermal process, the presence of MWCNTs possesses both acceleration and retardation effect on the crystallization of PPS without affecting the ultimate degree of crystallinity. Due to the interfacial interaction between MWCNTs and PPS, the MWCNTs can be uniformly dispersed in PPS. The interfacial crystallization of PPS on the surface of nanotubes was observed by scanning electron microscopy and transmission electron microscopy. A reinforcing effect of MWCNTs on the mechanical properties of PPS is found, which is considered to be relevant with the uniformly dispersed MWCNTs and the interfacial crystallization.

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Characterizations of Polypropylene/Single-Walled Carbon Nanotube Nanocomposites Prepared by the Novel Melt Processing Technique with a Controlled Residence Time

Processes ◽

10.3390/pr9081395 ◽

2021 ◽

Vol 9 (8) ◽

pp. 1395

Author(s):

Dongho Kang ◽

Sungwook Hwang ◽

Bichnam Jung ◽

Jinkie Shim

Keyword(s):

Carbon Nanotubes ◽

Percolation Threshold ◽

Residence Time ◽

Loss Modulus ◽

Complex Viscosity ◽

Processing Technique ◽

Melt Processing ◽

Melt Mixing ◽

Single Walled Carbon ◽

Twin Screw

Melt processing is considered one of the favored techniques to produce polymer nanocomposites with various inorganic fillers such as graphene and carbon nanotubes (CNTs). Due to their superior conductivity and tensile properties, among others, CNTs have been applied in broad applications. When a low filler fraction is desired, a high degree of dispersion is required in order to benefit from the intrinsic properties of CNTs. However, due to their high cohesive energy, dispersing CNTs in polymer melts is a difficult task. This study employed the melt mixing technique with a controlled residence time of 20 min to disperse single-walled carbon nanotubes (SWNTs) into a polypropylene matrix. The composites were prepared by using a corotating twin-screw extruder equipped with a back-conveying element with varying amounts of SWNTs from 0.29 to 6.56 wt.%. Mechanical, electrical, morphological, and rheological properties were evaluated. Due to the filler effect, storage, loss modulus, and complex viscosity increased with the SWNT content. Based on the van Gurp–Palmen plot, 0.29 wt.% SWNTs was the rheological percolation threshold, and the electrical property measurement revealed a 1.4 wt.% SWNT electrical percolation threshold based on the statistical percolation theory. Relatively large agglomerates were found when the SWNT content increased more than 1.28 wt.%.

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Non-Isothermal Crystallization Kinetic of Polyethylene/Carbon Nanotubes Nanocomposites Using an Isoconversional Method

Journal of Composites Science ◽

10.3390/jcs3010021 ◽

2019 ◽

Vol 3 (1) ◽

pp. 21 ◽

Cited By ~ 5

Author(s):

Beatriz Menezes ◽

Tiago Campos ◽

Thais Montanheiro ◽

Renata Ribas ◽

Luciana Cividanes ◽

...

Keyword(s):

Carbon Nanotubes ◽

Kinetic Parameters ◽

Isothermal Crystallization ◽

Crystallization Kinetic ◽

Model Fitting ◽

Kinetic Studies ◽

Isoconversional Method ◽

Degree Of Crystallinity ◽

Scanning Calorimetry ◽

Crystallite Sizes

Behavior studies of thermoplastic polymers during non-isothermal crystallization are extremely important since most of their properties are influenced by degree of crystallinity and the crystallization process. In general, an approach based on a model-fitting method is used to perform crystallization kinetic studies. Due to their inability to uniquely determine the reaction mode, many studies have used the isoconversional method, where it is not necessary to assume a crystallization model to obtain the kinetic parameters. Therefore, in this work, the influence of acid and octadecylamine functionalized carbon nanotubes (CNTs) in the crystallization kinetic of polyethylene (PE) was studied using an isoconversional method with differential scanning calorimetry (DSC) and polarized optical microscopy (POM). The kinetic parameters and the crystallization model were determined. The incorporation of functionalized and non-functionalized CNTs into PE did not change the Johnson-Mehl-Avrami crystallization model. However, the CNTs increased the crystallization temperature and reduced the activation energy for crystallization. In addition, the Avrami coefficient values were lower for the nanocomposites when compared to pure PE. The incorporation of CNTs accelerated the crystallization of PE, reducing the crystallite sizes and modifying their morphology.

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Morphology Origin of Gradually Weakened Thermal-Conductivity Enhancement for HDPE/MWCNTs Nanocomposites

Volume 8: Heat Transfer and Thermal Engineering ◽

10.1115/imece2016-65345 ◽

2016 ◽

Author(s):

Xiao-Hong Yin ◽

Can Yang ◽

Shiju E ◽

Xiping Li ◽

Jianbo Cao

Keyword(s):

Thermal Conductivity ◽

Phonon Scattering ◽

Loss Modulus ◽

Low Frequency ◽

Complex Viscosity ◽

Thermal Conductivity Enhancement ◽

Mwcnt Content ◽

Conductivity Enhancement ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

In this work, high-density polyethylene/multi-walled carbon nanotubes (HDPE/MWCNTs) nanocomposites containing various filler loadings (i.e., 0.5∼16.0 wt.%) were prepared with their thermal conductivities determined using a laser-based analyzer. It was found that although the nanocomposite’s thermal conductivity increased with elevated MWCNT content, the enhancement degree lowered gradually. Rheology and microstructure characterizations were performed to reveal the morphology origin of gradually weakened thermal-conductivity enhancement. The dynamic rheology measurements showed that all nanocomposites exhibited higher storage modulus (G′), loss modulus (G″) as well as complex viscosity (η*) compared with the neat HDPE. More interestingly, the plateau of the flow regime formed at low frequency ranges with MWCNT loadings higher than 2.0 wt.% suggested the formation of the MWNCT network structures within the nanocomposites. The existence of such structures was further verified by the Cole-Cole curves obtained from the rheology testing and MWCNT distribution states from scanning electron microscope (SEM) results. The formation of MWCNT network lowered the degree of thermal-conductivity enhancement in such a way that it gave a larger possibility for MWCNTs to agglomerate, which led to phonon scattering that reduced the nanocomposite’s thermal conductivity.

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Effect of functionalization of multiwalled carbon nanotubes with aminated poly(ether sulfone) on thermal and mechanical properties of poly(ether ether ketone) nanocomposites

High Performance Polymers ◽

10.1177/0954008316661616 ◽

2016 ◽

Vol 29 (7) ◽

pp. 857-868 ◽

Cited By ~ 5

Author(s):

Haizheng Cheng ◽

Ming Chen

Keyword(s):

Electron Microscopy ◽

Carbon Nanotubes ◽

Multiwalled Carbon Nanotubes ◽

Degree Of Crystallinity ◽

Acid Oxidation ◽

Scanning Calorimetry ◽

Multiwalled Carbon ◽

Ether Ether Ketone ◽

Poly Ether Ether Ketone ◽

Ether Ketone

Multiwalled carbon nanotubes (MWCNTs) were functionalized with aminated poly(ether sulfone) (PES) through the amidation reaction. Characterizations by Fourier transform infrared spectroscopy and X-ray diffraction corroborated the success of grafting reaction. Raman spectra reveal that no further damage occurred after the anchoring of PES to the carboxylated MWCNTs. Transmission electron microscopy shows that PES functionalization resulted in better dispersion of MWCNTs than acid oxidation. Poly(ether ether ketone) (PEEK)/MWCNTs functionalized with PES (PES-MWCNTs) nanocomposites were fabricated by solution-mixing and compression-molding techniques. Thermogravimetric analysis indicates that PES-MWCNTs/PEEK nanocomposites have the highest degradation temperature and thermal stability. Furthermore, noticeable increases in the crystallization and melting temperature as well as in the degree of crystallinity were found from differential scanning calorimetry thermograms, attributed to the strong heterogeneous nucleating role of PES-MWCNTs. Tensile test presents that the attachment of PES to the surface of MWCNTs exceptionally improved the tensile strength and Young’s modulus, and obtained moderate elongation at break. Impact toughness test and dynamic mechanical analysis show that the addition of PES-MWCNTs greatly enhanced the toughness and storage modulus of PEEK, respectively. These results are attributed to improved dispersion of PES-MWCNTs and strong interfacial adhesion to matrix, which is evidenced by scanning electron microscopy.

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