Ternary Nanocomposite System Composing of Graphene Nanoplatelet, Cellulose Nanofiber and Jatropha Oil Based Waterborne Polyurethane: Characterizations, Mechanical, Thermal Properties and Conductivity

This work aims to evaluate the performance of graphene nanoplatelet (GNP) as conductive filler with the presence of 0.5 wt.% cellulose nanofiber (CNF) on the physical, mechanical, conductivity and thermal properties of jatropha oil based waterborne polyurethane. Polyurethane was made from crude jatropha oil using an epoxidation and ring-opening process. 0.5, 1.0, 1.5, 2.0 wt.% GNP and 0.5 wt.% CNF were incorporated using casting method to enhance film performance. Mechanical properties were studied following standard method as stated in ASTM D638-03 Type V. Thermal stability of the nanocomposite system was studied using thermal gravimetric analysis (TGA). Filler interaction and chemical crosslinking was monitored using Fourier-transform infrared spectroscopy (FTIR) and film morphology were observed with field emission scanning electron microscopy (FESEM). Water uptake analysis, water contact angle and conductivity tests are also carried out. The results showed that when the GNP was incorporated at fixed CNF content, it was found to enhance the nanocomposite film, its mechanical, thermal and water behavior properties as supported by morphology and water uptake. Nanocomposite film with 0.5 wt.% GNP shows the highest improvement in term of tensile strength, Young’s modulus, thermal degradation and water behavior. As the GNP loading increases, water uptake of the nanocomposite film was found relatively small (<1%). Contact angle test also indicates that the film is hydrophobic with addition of GNP. The conductivity properties of the nanocomposite film were not enhanced due to electrostatic repulsion force between GNP sheet and hard segment of WBPU. Overall, with addition of GNP, mechanical and thermal properties was greatly enhanced. However, conductivity value was not enhanced as expected due to electrostatic repulsion force. Therefore, ternary nanocomposite system is a suitable candidate for coating application.

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Effect of Cellulose Nanofibrils on the Properties of Jatropha Oil-Based Waterborne Polyurethane Nanocomposite Film

Polymers ◽

10.3390/polym13091460 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1460

Author(s):

Mohamad Ridzuan Amri ◽

Chuah Teong Guan ◽

Syeed Saifulazry Osman Al-Edrus ◽

Faizah Md Yasin ◽

Siti Fatahiyah Mohamad

Keyword(s):

Thermal Properties ◽

Nanocomposite Film ◽

Cellulose Nanofibrils ◽

Waterborne Polyurethane ◽

Nanocomposite Films ◽

Test Machine ◽

Mechanical And Thermal Properties ◽

Gravimetric Analysis ◽

Jatropha Oil ◽

Opening Method

The objective of this work was to study the influence of cellulose nanofibrils (CNF) on the physical, mechanical, and thermal properties of Jatropha oil-based waterborne polyurethane (WBPU) nanocomposite films. The polyol to produce polyurethane was synthesized from crude Jatropha oil through epoxidation and ring-opening method. The chain extender, 1,6-hexanediol, was used to improve film elasticity by 0.1, 0.25, and 0.5 wt.% of CNF loading was incorporated to enhance film performance. Mechanical performance was studied using a universal test machine as specified in ASTM D638-03 Type V and was achieved by 0.18 MPa at 0.5 wt.% of CNF. Thermal gravimetric analysis (TGA) was performed to measure the temperature of degradation and the chemical crosslinking and film morphology were studied using Fourier-transform infrared spectroscopy (FTIR) and field emission scanning electron microscopy (FESEM). The results showed that when the CNF was incorporated, it was found to enhance the nanocomposite film, in particular its mechanical and thermal properties supported by morphology. Nanocomposite film with 0.5 wt.% of CNF showed the highest improvement in terms of tensile strength, Young’s modulus, and thermal degradation. Although the contact angle decreases as the CNF content increases, the effect on the water absorption of the film was found to be relatively small (<3.5%). The difference between the neat WPBU and the highest CNF loading film was not more than 1%, even after 5 days of being immersed in water.

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Water uptake of various electrospun nonwovens

Current Directions in Biomedical Engineering ◽

10.1515/cdbme-2020-3040 ◽

2020 ◽

Vol 6 (3) ◽

pp. 155-158

Author(s):

Katharina Wulf ◽

Volkmar Senz ◽

Thomas Eickner ◽

Sabine Illner

Keyword(s):

Contact Angle ◽

Surface Modification ◽

Water Absorption ◽

Water Uptake ◽

Biomedical Applications ◽

High Surface ◽

Volume Ratio ◽

Polymer Composition ◽

Water Wetting ◽

Morphology Changes

AbstractIn recent years, nanofiber based materials have emerged as especially interesting for several biomedical applications, regarding their high surface to volume ratio. Due to the superficial nano- and microstructuring and the different wettability compared to nonstructured surfaces, the water absorption is an important parameter with respect to the degradation stability, thermomechanic properties and drug release properties, depending on the type of polymer [1]. In this investigation, the water absorption of different non- and plasma modified biostable nanofiber nonwovens based on polyurethane, polyester and polyamide were analysed and compared. Also, the water absorption by specified water wetting, the contact angle and morphology changes were examined. The results show that the water uptake is highly dependent on the surface modification and the polymer composition itself and can therefore be partially changed.

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Fabrication and Evaluation of Nano-TiO2 Superhydrophobic Coating on Asphalt Pavement

Materials ◽

10.3390/ma14010211 ◽

2021 ◽

Vol 14 (1) ◽

pp. 211

Author(s):

Hongfeng Li ◽

Xiangwen Lin ◽

Hongguang Wang

Keyword(s):

Contact Angle ◽

Stearic Acid ◽

Asphalt Pavement ◽

Asphalt Mixture ◽

Waterborne Polyurethane ◽

Superhydrophobic Coating ◽

Nano Tio2 ◽

Sem Image ◽

Low Surface Energy ◽

Water Damage

In order to address water damage of asphalt pavement, reduce the occurrence of water-related potholes, deformation, and other diseases, and improve the performance and service life of the pavement, a nano-TiO2 superhydrophobic coating (PSC) on asphalt pavement was prepared from waterborne polyurethane and nano-TiO2 modified by stearic acid. FT-IR measured stearic acid successfully modified low surface energy substance on the surface of nano-TiO2. The SEM image shows that the PSC has a rough surface structure. The contact angle and rolling angle of the PSC in the contact angle test are 153.5° and 4.7°, respectively. PSC has a super-hydrophobic ability, which can improve the water stability of the asphalt mixture. Although the texture depth and pendulum value have been reduced by 2.5% and 4.4%, respectively, they all comply with the standard requirements. After the abrasion resistance test, the PSC coating still has a certain hydrophobic ability. These results surface PSC coating can effectively reduce water damage on asphalt pavement, and has considerable application value.

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Enhancement of tribological properties and characteristic of polymer matrix composite (UHMWPE reinforced with short fibres of polyester) for Total Disc Replacement (TDR)

Journal of Achievements of Materials and Manufacturing Engineering ◽

10.5604/01.3001.0014.6775 ◽

2020 ◽

Vol 2 (102) ◽

pp. 55-65

Author(s):

M.N. Obaid ◽

S.H. Radhi

Keyword(s):

Surface Roughness ◽

Contact Angle ◽

Wear Resistance ◽

Composite Material ◽

Thermal Properties ◽

Coefficient Of Friction ◽

Tribological Properties ◽

Total Disc Replacement ◽

Short Fibres ◽

The Matrix

Purpose: The number of people suffering from Degenerative Disc Disease (DDD) is increasing. The disease causes heavy pain and restrict a number of day-to-day life activities. In extreme cases, the degraded disc is removed under total disc replacement which is usually made up of Ultra-High Molecular Weight Polyethylene (UHMWPE). The material has astounding biocompatible characteristics mechanical properties and wear resistance. However, these characteristics are insufficient in arthroplasty application. Therefore, research investigations are ongoing to improve tribological properties through reinforcement that may result in a composite material of UHMWPE. Thus the current study is aimed at reinforcing UHMWPE with short fibres of polyesters to enhance the tribological properties and surface characteristic so as to improve wear resistance and nourish the fibroblast cells on synthetic disc. Design/methodology/approach: The researcher prepared UHMWPE composite material, reinforced with different weight fractions of short polyester fibres (2, 4, 6, 8 and 10% following hot press method. Further pin-on-disc device was used to study the tribological properties (coefficient of friction and volume of wear). The study tested surface roughness and surface characteristics by atomic force microscopy (AFM) device, hardness by shore D device, contact angle to study the effect of polyester short fibres on wettability of UHMWPE surface and tested the thermal properties and crystalline degree using Differential Scanning Calorimetry measurement (DSC) device. Findings: The results infer that the wear resistance got improved when using 2% w.t polyester though it got decreased initially. However, the value was still more than neat UHMWPE. There was a decrease observed in coefficient of friction, but after 4 w.t% polyester, the coefficient of friction got increased due to increasing percentage of fibres which make it harder and stiff compared to UHMWPE. There was a decline observed in surface roughness due to alignment of the fibres with smooth surface. The contact angle got increased in a moderate range while the roughness enhanced the growth of fibroblast cell. The hardness of composite material got increased, because the fibres turned stiffer and harder than the matrix. DSC results infer the improvements in thermal stability due to high thermal properties of polyester fibres compared to UHMWPE. The degree of crystallinity got increased which in turn enhanced wear resistance, especially at 6 w.t % polyester fibres. There was a mild increase observed in density since the density of polyester is higher than polymer. Research limitations/implications: The major challenge was the dispersion of fibres. Uniform distribution of fibres within the matrix (UHMWPE) was achieved through two steps of mixing processes such as mechanical mixture and twin extruder. In future studies, fatigue tests must be conducted to study the behaviour of prepared composite materials under fatigue cycle. Practical implications: A significant objective is how to connect among different properties to obtain good improvement in tribological and surface properties so as to enhance wear resistance and growth of fibrolase cells. Originality/value: In this study, polymeric short fibres were used as reinforcement with polymeric matrix to enhance the wettability of fibres with matrix. In this way, the bonding among them got increased which supports the tribological, surface, and crystalline behaviour.

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In situ Synthesis and mechanical, thermal properties of polyimide nanocomposite film by addition of functionalized graphene oxide

Polymer Composites ◽

10.1002/pc.23249 ◽

2014 ◽

Vol 37 (3) ◽

pp. 907-914 ◽

Cited By ~ 22

Author(s):

Peijiang Liu ◽

Zhengjun Yao ◽

Lin Li ◽

Jintang Zhou

Keyword(s):

Graphene Oxide ◽

Thermal Properties ◽

Nanocomposite Film ◽

In Situ Synthesis ◽

Functionalized Graphene ◽

Functionalized Graphene Oxide ◽

Polyimide Nanocomposite

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Colloidal stability and rheology of jatropha oil-based waterborne polyurethane (JPU) dispersion

Progress in Organic Coatings ◽

10.1016/j.porgcoat.2018.09.018 ◽

2018 ◽

Vol 125 ◽

pp. 348-357 ◽

Cited By ~ 9

Author(s):

Sariah Saalah ◽

Luqman Chuah Abdullah ◽

Min Min Aung ◽

Mek Zah Salleh ◽

Dayang Radiah Awang Biak ◽

...

Keyword(s):

Colloidal Stability ◽

Waterborne Polyurethane ◽

Jatropha Oil

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Synergetic effect of graphene nanoplatelet, carbon fiber and coupling agent addition on the tribological, mechanical and thermal properties of polyamide 6,6 composites

Composites Part B Engineering ◽

10.1016/j.compositesb.2019.01.014 ◽

2019 ◽

Vol 163 ◽

pp. 730-739 ◽

Cited By ~ 9

Author(s):

Ecem Karatas ◽

Okan Gul ◽

Nevin Gamze Karsli ◽

Taner Yilmaz

Keyword(s):

Thermal Properties ◽

Carbon Fiber ◽

Coupling Agent ◽

Synergetic Effect ◽

Mechanical And Thermal Properties ◽

Graphene Nanoplatelet

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The Effects of Aluminum-Nitride Nano-Fillers on the Mechanical, Electrical, and Thermal Properties of High Temperature Vulcanized Silicon Rubber for High-Voltage Outdoor Insulator Applications

Materials ◽

10.3390/ma12213562 ◽

2019 ◽

Vol 12 (21) ◽

pp. 3562 ◽

Cited By ~ 1

Author(s):

Chang Liu ◽

Yiwen Xu ◽

Daoguang Bi ◽

Bing Luo ◽

Fuzeng Zhang ◽

...

Keyword(s):

Contact Angle ◽

Thermal Properties ◽

High Temperature ◽

High Voltage ◽

Breakdown Strength ◽

Electrical Breakdown ◽

Theoretical Models ◽

Dielectric Constants ◽

Silicon Rubber ◽

Electrical Breakdown Strength

AlN nanoparticles were added into commercial high-temperature-vulcanized silicon rubber composites, which were designed for high-voltage outdoor insulator applications. The composites were systematically studied with respect to their mechanical, electrical, and thermal properties. The thermal conductivity was found to increase greatly (>100%) even at low fractions of the AlN fillers. The electrical breakdown strength of the composites was not considerably affected by the AlN filler, while the dielectric constants and dielectric loss were found to be increased with AlN filler ratios. At higher doping levels above 5 wt% (~2.5 vol%), electrical tracking performance was improved. The AlN filler increased the tensile strength as well as the hardness of the composites, and decreased their flexibility. The hydrophobic properties of the composites were also studied through the measurements of temperature-dependent contact angle. It was shown that at a doping level of 1 wt%, a maximum contact angle was observed around 108°. Theoretical models were used to explain and understand the measurement results. Our results show that the AlN nanofillers are helpful in improving the overall performances of silicon rubber composite insulators.

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