scholarly journals Effect of Alkaline treatment on the characteristics of pineapple leaves fibre and PALF/PP biocomposite

2021 ◽  
Vol 15 (4) ◽  
pp. 8518-8528
Author(s):  
S. Gnanasekaran ◽  
Noor Ida Amalina Ahamad Nordin ◽  
M.M.M. Hamidi ◽  
J.H. Shariffuddin
Keyword(s):  
Thermal Stability ◽  
Water Absorption ◽  
Synthetic Fibre ◽  
Alkaline Treatment ◽  
Natural Fibre ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Excellent Thermal Stability ◽  
Degradation Temperature ◽  
Pineapple Leaves

Pineapple leaves fibre (PALF) is one of the natural fibre that has high potential to substitute non-renewable synthetic fibre in thermoplastic products. The PALF were alkali treated with different concentrations of NaOH. Untreated and alkali treated PALF were characterized using Thermal Gravimetric Analysis (TGA) and Scanning Electron Microscopy (SEM) to determine the thermal stability and surface morphology of the fibres respectively. Biocomposites were prepared by reinforced alkali treated and untreated PALF with polypropylene (PP) matrix. Tensile properties and water absorption analysis of PALF/PP biocomposites were studied. Biocomposite with 8 wt.% of alkali treated PALF express excellent thermal stability, with maximum degradation temperature at 270 ℃ which is a 7.17% improvement compared to untreated PALF. This biocomposite also had increased tensile strength (116 MPa) with 43% improvement compared to untreated PALF/PP (66 MPa) biocomposite and had lower water absorption at 6% compared to untreated biocomposite which at 21%. Hence, alkali treated PALF is able to improve the characteristic of PALF and increase the compatibility between fibre and polymer by reducing hemicellulose and lignin components.

Thermal gravimetric analysis of in-situ crosslinked nanocellulose whiskers • poly(methyl vinyl ether-co-maleic acid) • polyethylene glycol

TAPPI Journal ◽  
2011 ◽  
Vol 10 (4) ◽  
pp. 29-33
Author(s):  
LEE A. GOETZ ◽  
AJI P. MATHEW ◽  
KRISTIINA OKSMAN ◽  
ARTHUR J. RAGAUSKAS
Keyword(s):  
Thermal Stability ◽  
Polyethylene Glycol ◽  
Vinyl Ether ◽  
Thermal Gravimetric Analysis ◽  
Maleic Acid ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Methyl Vinyl ◽  
Methyl Vinyl Ether

The thermal stability and decomposition of in-situ crosslinked nanocellulose whiskers – poly(methyl vinyl ether-co-maleic acid) – polyethylene glycol formulations (PMVEMA-PEG), (25%, 50%, and 75% whiskers) – were investigated using thermal gravimetric analysis (TGA) methods. The thermal degradation behavior of the films varied according to the percent cellulose whiskers in each formulation. The presence of cellulose whiskers increased the thermal stability of the PMVEMA-PEG matrix.

Synthesis, Characterization and Application of Multi-Generations Hyperbranched Polyurethane Based on Isophorone Diisocyanate

2012 ◽  
Vol 554-556 ◽  
pp. 126-129 ◽  
Author(s):  
Shun Yin ◽  
Ning Sun ◽  
Chun Yun Feng ◽  
Zhi Mou Wu ◽  
Zhao Hua Xu ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Raw Materials ◽  
Degradation Mechanism ◽  
Resonance Spectroscopy ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Isophorone Diisocyanate ◽  
Scanning Calorimetry ◽  
Degradation Temperature ◽  
Hyperbranched Polyurethane

A series of different generation hyperbranched polyurethane(HBPU) was synthesized based on the raw materials of isophorone diisocyanate(IPDI) and diethanolamine(DEOA). Their structure, thermal degradation mechanism and glass transition temperature(Tg) were characterized by fourier transform infrared spectroscopy(FTIR), nuclear magnetic resonance spectroscopy(NMR), thermal gravimetric analysis(TGA) and differential scanning calorimetry(DSC). The results showed that: the yield of each generation HBPU was up to 90%, different generation HBPU had almost the same initial degradation temperature(about at 200°C) and they all had two decomposition platforms; with the increase of generation, Tg increased from 107.2°C to 132.1°C. The gloss and hardness of the HBPU coatings were significantly improved.

scholarly journals Preparation, Characterization and Performance Properties of Polydodecylmethylsilsesquioxane Nanoparticles

Coatings ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1045
Author(s):  
Fuquan Deng ◽  
Hua Jin ◽  
Wei Xu
Keyword(s):  
Thermal Stability ◽  
Particle Size ◽  
Electron Microscope ◽  
Contact Angles ◽  
Process Conditions ◽  
Average Particle ◽  
Gravimetric Analysis ◽  
Laser Scattering ◽  
Excellent Thermal Stability ◽  
X Ray

A series of polydodecylmethylsilsesquioxane (PDMSQ) nanocomposite latexes were prepared via emulsion polymerization of methyltriethoxysilane (MTES) and dodecyltrimethoxysilane (DTMS) and sodium hydroxide as the catalyst, and sodium dodecyl benzene sulfonate/Tween 80 as the mixed emulsifiers. Effects of the emulsifier doses, the reaction temperature, the catalyst concentration and the oil/water ratio on the particle size and distribution of the PDMSQ nanoparticles were discussed. Particle size and micromorphology, structure, thermal stability, crystallinity and hydrophobicity of PDMSQ nanoparticles (PDMSQ NPs) were investigated by dynamic laser scattering (DLS), Fourier transform infrared spectroscopy (FTIR), silicon-nuclear magnetic resonance (28Si-NMR), X-ray photoelectron spectroscope (XPS), scanning electron microscope (SEM), transmission electron microscope (TEM), atomic force microscope (AFM), thermo gravimetric analysis (TGA), X-ray diffraction (XRD) and contact angle tester. Results showed that a series of PDMSQ NPs could be obtained with an average particle size of less than 80 nm and narrow distribution as well as spherical structure under the optimal process conditions. PDMSQ NPs exhibited excellent thermal stability and were mainly amorphous but also contained some crystal structures. Importantly, the static water contact angles (WCAs) on its latex films were larger than 150° and the WCAs hysteresis were less than 10°, thus those PDMSQ nanocomposite latexes show potential in the field of superhydrophobic coatings.

scholarly journals The Thermal Properties of Polyurethane/Neoprene Blends on Prosthetic Foot

2020 ◽  
Vol 990 ◽  
pp. 106-110
Author(s):  
Mohd Zulkifli Mohamad Noor ◽  
Mohamad Anas Mohd Azmi ◽  
Mohd Shaiful Zaidi Mad Desa ◽  
Mohd Bijarimi Mat Piah ◽  
Azizan Ramli
Keyword(s):  
Thermal Stability ◽  
Thermal Properties ◽  
Low Cost ◽  
Decomposition Temperature ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Prosthetic Foot ◽  
Reinforced Polymer ◽  
New Material ◽  
Thermal Stability Of

Neoprene reinforced polymer has become an attraction in current research and development of new material blend. In this invention, neoprene was chosen to be enhance to polyurethane because of their superior properties that possess extraordinary mechanical, electrical, optical and thermal properties on prosthetic foot. In this research, polyurethane was chosen due to good rigidity, easy processing and low cost. The reinforcement polyurethane with neoprene is expected to improve the properties of polyurethane. The objective of this research was conducted to investigate the effect of neoprene contents on thermal properties of polyurethane reinforced neoprene on prosthetic foot. The effect of neoprene on thermal properties neoprene reinforced polyurethane was analysed in term of its thermal stability by thermal gravimetric analysis (TGA). Moreover, the visual of small topographic details on the surface of polyurethane/neoprene blends will be examined by scanning electron microscope (SEM). Based on result, the thermal properties show the great enhancement at high neoprene contents which is 1.0wt%. The thermal stability of polyurethane reinforced neoprene improves when the temperature where decomposition starts to occurs are higher than decomposition temperature of pure polyurethane. Then, thermal conductivity of polyurethane shows the great improvement after the addition of neoprene. Lastly, the smooth surface and visible of sheets pattern on surface represent the present of neoprene disperse into polymer that enhance brittleness. Thus, the presence of neoprene has clearly enhanced the thermal stability of the polyurethane. Table 1 shows formulation of neoprene and polyurethane.

Synthesis and thermal stability studies of polyaniline/silver nanocomposite based on reduction of silver ions using polyaniline

2011 ◽  
Vol 23 (7) ◽  
pp. 513-517 ◽  
Author(s):  
Mohsen Ghorbani ◽  
Mohammad Soleimani Lashkenari ◽  
Hossein Eisazadeh
Keyword(s):  
Thermal Stability ◽  
Chemical Structure ◽  
Aqueous Media ◽  
Silver Ions ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Stability Studies ◽  
Scanning Calorimetry ◽  
Chemical Polymerization ◽  
Silver Nanocomposite

This study investigated the preparation and properties of polyaniline/silver (PAn/Ag2O) nanocomposite in aqueous media by chemical polymerization of aniline in the presence of ammonium peroxydisulphate as an oxidant. The products were investigated in terms of morphology, chemical structure, thermal stability and thermal degradation using scanning electron microscopy, Fourier transform infrared, thermal gravimetric analysis and differential scanning calorimetry, respectively. The results indicated that the properties of products were dependent on the nanocomposite structure.

Study on the thermal stability of Controlled Permeability Formwork

2011 ◽  
Vol 374-377 ◽  
pp. 1426-1429
Author(s):  
Xiao Meng Guo ◽  
Jian Qiang Li ◽  
Xian Sen Zeng ◽  
De Dao Hong
Keyword(s):  
Thermal Stability ◽  
Thermal Properties ◽  
Dynamic Mechanical Analysis ◽  
Thermo Gravimetric Analysis ◽  
Mechanical Analysis ◽  
Gravimetric Analysis ◽  
Construction Work ◽  
Thermo Gravimetric ◽  
Excellent Thermal Stability ◽  
Thermal Stability Of

In this study, the thermal properties of a kind of new geotextile materials, so called controlled permeable formwork (CPF), were studied. Thermo-gravimetric analysis showed that the weight of CPF didn’t change much between 0~350 °C. Dynamic mechanical analysis showed that the storage modulus of CPF reduced from 25 MPa to around 10 MPa when the temperature rose to above 100 °C. The strength of sample decreased slightly with the increase of the temperature. The breaking elongation changed slightly with a maximum at 80 °C. The CPF showed excellent thermal stability and was suitable for general use in construction work.

Preparation and Properties of Silane-Terminated Poly(urethane-Imide)

2013 ◽  
Vol 690-693 ◽  
pp. 1577-1580
Author(s):  
Xiao Xi Hu ◽  
Yun Wang
Keyword(s):  
Thermal Stability ◽  
Water Resistance ◽  
Tensile Tests ◽  
Mechanical Analysis ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Silane Coupling ◽  
Ft Ir ◽  
And Storage ◽  
Thermal Stability Of

A serious of silane-terminated poly (urethane-imide) (Si-PUI) was synthesized via prepolymer method using polycarbonatediols (PCDL), 2,4-tolylene diisocyanate (TDI), 4,4'-Oxydiphthalic Anhydride (ODPA) and silane coupling agent KH-550. The structure of the products was characterized by FT-IR. The thermal properties were measured by thermal gravimetric analysis (TGA). The thermal mechanical behavior was investigated by dynamic mechanical analysis (DMA).The mechanical characteristic was measured by tensile tests. The water absorption (Wa) was also been tested. With the imide content increasing, the thermal stability, tensile strength and storage modulus of poly (urethane-imide) improve significantly, and the glass transition temperature rises. The introduction of silanes improves the water resistance and further enhances the thermal stability of poly (urethane-imide).

scholarly journals Water Absorption Behaviour and Mechanical Performance of Pineapple Leaf Fibre Reinforced Polylactic Acid Composites

2018 ◽  
Vol 15 (4) ◽  
pp. 5760-5774 ◽  
Author(s):  
E. H. Agung ◽  
M. H. M. Hamdan ◽  
Januar Parlaungan Siregar ◽  
D. Bachtiar ◽  
C. Tezara ◽  
...  
Keyword(s):  
Water Absorption ◽  
Polylactic Acid ◽  
Synthetic Fibre ◽  
Mechanical Performance ◽  
Raw Materials ◽  
Scientific Work ◽  
Natural Fibre ◽  
Compression Moulding ◽  
Alternative Sources ◽  
Flexural Tests

Fast-growing scientific work is focusing on alternative sources to replace modern synthetic fibre materials due to the adverse effects caused by petroleum-based materials. Natural fibre possesses high potential as a replacement for synthetic fibre and petroleum-based products. These materials are not only greener and environmental-friendly, but also safe for human health. As such, this study investigated the influence of compatibilising agent of maleated anhydride polyethylene (MAPE) on mechanical performance of pineapple leaf fibre (PALF) reinforced polylactic acid (PLA). The raw materials, such as PALF, PLA, and MAPE, were mixed by using a hot roller mixer machine and hot compression moulding at 190ºC. The specimens were then tested for water absorption and flexibility. The specimens were submerged in water for 0, 7, 14, and 21 days. Three types of tests were conducted, namely water absorption, tensile, and flexural assessments. The results of water absorption, tensile, and flexural tests for the untreated PALF composite (UPALF) and treated PLAF composite (TPALF) were recorded and explained. As a conclusion, composite materials based on hydrophilic natural fibre may reduce the tensile and flexural properties of the composite.

Thermal Gravimetric Analysis of Unsaturated Polyesters Filled with Alumina Trihydrate and Silica Aerogel

2017 ◽  
Vol 264 ◽  
pp. 116-119 ◽  
Author(s):  
Zulhelmi Alif Abdul Halim ◽  
Muhamad Azizi Mat Yajid ◽  
Mohd Hasbullah Idris ◽  
Halimaton Hamdan
Keyword(s):  
Thermal Stability ◽  
Thermal Gravimetric Analysis ◽  
Silica Aerogel ◽  
Polyester Resin ◽  
Unsaturated Polyester ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Polyester Matrix ◽  
Alumina Trihydrate ◽  
Thermal Stability Of

Thermal degradation of the composite blend consisting unsaturated polyester resin, alumina trihydrate and silica aerogel was studied using thermal gravimetric analysis. Composite filled with silica aerogel show lower density and slightly improve the thermal stability of the pure polymer. The addition of alumina trihydrate slows down the degradation of the polymer due to the release of bond water while the combination of silica aerogel and alumina trihydrate in polyester matrix does not interrupt the function of alumina trihydrate due to inert properties of silica aerogel.

Buckling of Two-Dimensional Covalent Organic Frameworks Under Thermal Stress

2019 ◽  
Author(s):  
Austin Evans ◽  
Matthew Ryder ◽  
Nathan C. Flanders ◽  
Edon Vitaku ◽  
Lin Chen ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Thermal Stress ◽  
Density Functional ◽  
Structural Changes ◽  
Gravimetric Analysis ◽  
Two Dimensional ◽  
Covalent Organic Frameworks ◽  
X Ray Diffraction ◽  
Excellent Thermal Stability ◽  
X Ray

Two-dimensional Covalent organic frameworks (2D COFs) are periodic, permanently porous, and lightweight solids that are polymerized from topologically designed monomers. The predictable design and structural modularity of these materials make them promising candidates for applications including catalysis, environmental remediation, chemical separations, and organic electronics, many of which will require stability to mechanical and thermal stress. Based on their reinforced structures and high degradation temperatures as determined by thermal gravimetric analysis (TGA), many reports have claimed that COFs have excellent thermal stability. However, their stability to heat and pressure has not been probed using methods that report on structural changes rather than the loss of volatile compounds. Here we explore two structurally analogous 2D COFs with different polymerization chemistries using in operando X-ray diffraction, which demonstrates the loss of crystallinity at lower temperatures than the degradation temperatures measured by TGA. Density functional theory calculations suggest that an asymmetric buckling of the COF lattice is responsible for the observed loss of crystallinity. In addition to their thermal stability, x-ray diffraction of the 2D COFs under gas pressures up to 100 bar showed no loss in crystallinity or structural changes, indicating that these materials are robust to mechanical stress by applied pressure. We expect that these results will encourage further exploration of COF stability as a function of framework design and isolated form, which will guide the design of frameworks that withstand demanding application-relevant conditions.

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