scholarly journals Obtaining and characterization films of a bioplastic obtained from passion fruit waste (Passiflora edulis)

2021 ◽  
Author(s):  
Luz Stella Henao-Díaz ◽  
Cristian Leonardo Cadena-Casanova ◽  
Gloria Ivette Bolio López ◽  
Lucien Veleva ◽  
José Antonio Azamar-Barrios ◽  
...  
Keyword(s):  
Citric Acid ◽  
Crystallinity Index ◽  
Passion Fruit ◽  
Ftir Analysis ◽  
X Ray Diffraction ◽  
Citric Acid Concentration ◽  
Passiflora Edulis ◽  
X Ray ◽  
Polymeric Chains ◽  
Citric Acid Content

Objective: Obtaining films from a vegetable biopolymer from the peel (a by-product) of passion fruit (Passiflora edulis) (BPM) and contribute to reduce the environmental pollution generated by the consumption of petroleum-derived plastics.Design / methodology / approach: By acid hydrolysis at four concentrations of citric acid (0, 1, 2, and 3 %), pectin was extracted of passion fruit peels, making a paste mixture with glycerol. The obtained biofilms with an approximate 1 mm thickness wereNcharacterized by transformed Fourier infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) with coupled elemental analyzer (EDS).Results: XRD diffractograms revealed that passion fruit bioplastic had a semi-crystalline structure and a calculated crystallinity index of 74.6 %. Its value reduced by the half as the citric acid increased concentration, the samples with lower concentration with greater flexibility (1 %). FTIR analysis suggested alterations in the BMP structures and adecrease of methoxyl groups in the polymeric chains with the increasing in citric acid content. Limitations/implications: SEM micrographs showed homogeneity in the films, although with some granular irregularities and folding.Findings/conclusions: The increase in citric acid concentration decreased the degree of gelation in the writing of the obtained biofilms, suggested by EDS and FTIR results, with a consequent reduced flexibility of the GMP films.

Experimental Investigation of Surface Modified Abaca Fibre

2020 ◽  
Vol 978 ◽  
pp. 291-295 ◽  
Author(s):  
Agnivesh Kumar Sinha ◽  
Harendra Kumar Narang ◽  
Somnath Bhattacharya
Keyword(s):  
Polymer Composites ◽  
Amorphous Materials ◽  
Crystallinity Index ◽  
Surface Modifications ◽  
Xrd Analysis ◽  
Natural Fibres ◽  
Ftir Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Surface Modified

Natural fibres have gained popularity due to their use in fabrication of biodegradable polymer composites which are not only non-polluting but are also light weight and inexpensive. Abaca fibres are known for their remarkable properties for which their polymer composites are used in automotive applications. However, hydrophilicity and compatibility with polymer matrices are the two major drawbacks of natural fibres which restrict their use as reinforcements in polymer composites. Therefore, present study deals with the surface modifications of abaca fibre using potassium permanganate and sodium hydroxide solutions to enhance crystallinity and reduce hydrophilicity of abaca fibres. Further, the surfaces of untreated and treated fibre were investigated with the help of Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis. Surface treatment of abaca fibre led to the removal of unwanted wax, and other amorphous materials which was confirmed through FTIR analysis. Crystallinity index was found to be 57%, 59% and 61% for untreated, NaOH treated and KMnO4 treated abaca fibre respectively.

Electro-Less Ni-P Plating Coating of In Situ TiCp/Al-4.5wt.%Cu Vomposites

2015 ◽  
Vol 817 ◽  
pp. 593-598
Author(s):  
Yan Feng Liang ◽  
Sheng Quan Dong ◽  
Gao Hong Li
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Citric Acid ◽  
Optical Microscopy ◽  
X Ray Diffraction ◽  
Citric Acid Concentration ◽  
X Ray ◽  
In Situ Tic ◽  
Scanning Electron

In situ TiCp/Al-4.5wt.%Cu composites have been coated using an electro-less Ni-P plating technique. The morphology and composition of the plating coating have been examined by scanning electron microscopy, optical microscopy, and X-ray diffraction. The results indicated that the coating had a high-phosphorus amorphous microstructure. The coatings microstructures showed significantly changes when the citric acid concentration in the chemical bath was varied in the range 16-20g/L.

scholarly journals Valorization of Byproducts of Hemp Multipurpose Crop: Short Non-Aligned Bast Fibers as a Source of Nanocellulose

Molecules ◽  
2021 ◽  
Vol 26 (16) ◽  
pp. 4723
Author(s):  
Sara Dalle Vacche ◽  
Vijayaletchumy Karunakaran ◽  
Alessia Patrucco ◽  
Marina Zoccola ◽  
Loreleï Douard ◽  
...  
Keyword(s):  
Infrared Spectroscopy ◽  
Thermogravimetric Analysis ◽  
Cannabis Sativa ◽  
Crystallinity Index ◽  
Residual Lignin ◽  
Chemical Pretreatment ◽  
X Ray Diffraction ◽  
X Ray ◽  
Bast Fibers ◽  
Seed Maturity

Nanocellulose was extracted from short bast fibers, from hemp (Cannabis sativa L.) plants harvested at seed maturity, non-retted, and mechanically decorticated in a defibering apparatus, giving non-aligned fibers. A chemical pretreatment with NaOH and HCl allowed the removal of most of the non-cellulosic components of the fibers. No bleaching was performed. The chemically pretreated fibers were then refined in a beater and treated with a cellulase enzyme, followed by mechanical defibrillation in an ultrafine friction grinder. The fibers were characterized by microscopy, infrared spectroscopy, thermogravimetric analysis and X-ray diffraction after each step of the process to understand the evolution of their morphology and composition. The obtained nanocellulose suspension was composed of short nanofibrils with widths of 5–12 nm, stacks of nanofibrils with widths of 20–200 nm, and some larger fibers. The crystallinity index was found to increase from 74% for the raw fibers to 80% for the nanocellulose. The nanocellulose retained a yellowish color, indicating the presence of some residual lignin. The properties of the nanopaper prepared with the hemp nanocellulose were similar to those of nanopapers prepared with wood pulp-derived rod-like nanofibrils.

scholarly journals Thermal and optical properties of new poly(amide-imide)-nanocomposite reinforced by layer silicate based on chiral n-trimellitylimido-L-valine

2012 ◽  
Vol 31 (1) ◽  
pp. 79
Author(s):  
Khalil Faghihi ◽  
Masoumeh Soleimani ◽  
Shabnam Nezami ◽  
Meisam Shabanian
Keyword(s):  
Main Chain ◽  
Nanocomposite Films ◽  
Direct Polycondensation ◽  
Polycondensation Reaction ◽  
X Ray Diffraction ◽  
Solution Intercalation ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Polymeric Chains ◽  
Morphology And Structure

Two new samples of poly(amide-imide)-montmorillonite reinforced nanocomposites containing N-trimellitylimido-L-valine moiety in the main chain were synthesized by a convenient solution intercalation technique. Poly(amide-imide) (PAI) 5 as a source of polymer matrix was synthesized by the direct polycondensation reaction of N-trimellitylimido-L-valine (3) with 4,4′-diaminodiphenyl ether 4 in the presence of triphenyl phosphite (TPP), CaCl2, pyridine and N-methyl-2-pyrrolidone (NMP). Morphology and structure of the resulting PA-nanocomposite films (5a) and (5b) with 10 and 20 % silicate particles were characterized by FTIR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effect of clay dispersion and the interaction between clay and polymeric chains on the properties of nanocomposite films were investigated by using Uv-vis spectroscopy,  thermogravimetric analysis (TGA) and water uptake measurements.

scholarly journals Two-Step Separation of Chitin from Shrimp Shells Using Citric Acid and Deep Eutectic Solvents with the Assistance of Microwave

Polymers ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 409 ◽  
Author(s):  
Dandan Zhao ◽  
Wen-Can Huang ◽  
Na Guo ◽  
Shuye Zhang ◽  
Changhu Xue ◽  
...  
Keyword(s):  
Citric Acid ◽  
Deep Eutectic Solvents ◽  
Second Step ◽  
X Ray Diffraction ◽  
X Ray ◽  
Shrimp Shells ◽  
Ft Ir ◽  
Scanning Electron ◽  
Ft Ir Spectroscopy

In this research, a two-step extraction approach was developed for chitin preparation from shrimp shells by utilizing citric acids and deep eutectic solvents (DESs), which effectively removed minerals and proteins. In the first step, minerals of shrimp shells were removed by citric acid, and the demineralization efficiency reached more than 98%. In the second step, the removal of protein was carried out using deep eutectic solvents with the assistance of microwave, and the deproteinization efficiency was more than 88%. The results of scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction analysis (XRD), and thermogravimetric analysis (TGA) showed that the quality of DES-prepared chitin was comparable to that of traditional acid/alkali-prepared chitin. These results were realized without utilizing hazardous chemicals, which are detrimental to the environment. This research indicates that a DES-based preparation approach has the potential for application in the recovery of biopolymers from natural resources.

scholarly journals Preparation and Properties of Nanocellulose from Miscanthus x giganteus

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Valerii A. Barbash ◽  
Olha V. Yashchenko ◽  
Olesia A. Vasylieva
Keyword(s):  
Structural Changes ◽  
Thermochemical Treatment ◽  
Crystallinity Index ◽  
Alkaline Treatment ◽  
X Ray Diffraction ◽  
Miscanthus X Giganteus ◽  
X Ray ◽  
Second Stage ◽  
20 Nm ◽  
Hydrolysis Of

Miscanthus x giganteus stalks were used to make organosolvent pulp and nanocellulose. The organosolvent miscanthus pulp (OMP) was obtained through thermal treatment in the mixture of glacial acetic acid and hydrogen peroxide at the first stage and the alkaline treatment at the second stage. Hydrolysis of the never-dried OМP was carried out by a solution of sulfuric acid with concentrations of 43% and 50% and followed by ultrasound treatment. Structural changes and the crystallinity index of OMP and nanocellulose were studied by SEM and FTIR methods. X-ray diffraction analysis confirmed an increase in the crystallinity of OMP and nanocellulose as a result of thermochemical treatment. We show that nanocellulose has a density of up to 1.6 g/cm3, transparency up to 82%, and a crystallinity index of 76.5%. The AFM method showed that the particles of nanocellulose have a diameter in the range from 10 to 20 nm. A thermogravimetric analysis confirmed that nanocellulose films have a denser structure and lower mass loss in the temperature range of 320–440°C compared to OMP. The obtained nanocellulose films have high tensile strength up to 195 MPa. The nanocellulose obtained from OMP exhibits the improved properties for the preparation of new nanocomposite materials.

scholarly journals Darstellung und Kristallstrukturen von (PH4P)4Sb8I28 und (Ph4P)Sb3I10(Ph = C6H5) / Synthesis and Crystal Structures of (PH4P)4Sb8I28 and (Ph4P)Sb3I10(Ph = C6H5)

1987 ◽  
Vol 42 (12) ◽  
pp. 1493-1499 ◽  
Author(s):  
Siegfried Pohl ◽  
Wolfgang Saak ◽  
Detlev Haase
Keyword(s):  
Single Crystal ◽  
Crystal Structures ◽  
Diffraction Data ◽  
Lone Pair ◽  
X Ray Diffraction ◽  
Triclinic Space Group ◽  
X Ray ◽  
Molar Ratios ◽  
Polymeric Chains ◽  
Bond Strengths

AbstractThe compounds (Pn4P)4Sb8I28 (1) and (Ph4P)Sb3I10 (2) were prepared by the reaction of SbI3 and Ph4PI in acetonitrile (molar ratios 2:1 and 3:1 respectively). The structures of 1 and 2 were determined from single crystal X-ray diffraction data.1 crystallizes in the triclinic space group P1̄ with a - 1321.7(5). b = 1346.7(5), c = 2201.8(8) pm, α = 104.18(2). β = 99.92(2), γ = 100.33(2)°; 2: monoclinic, C2/c, a = 2371.1(2), b = 745.0(1), c = 2495.1(2) pm, β = 100.75(1)°.Whereas 1 exhibits isolated Sb8I284- ions, the anions of 2 are built up of polymeric chains [Sb3I10- ]∞. In both compounds the distorted Sbl6 octahedra are linked by common edges. The Sb-I distances are in the range between 277.4 and 354.8 pm (1) and between 277.4 and 342.4 pm (2). The observed structures do not only depend on stoichiometry, the nature of the counter cations, and the possibility of oligomerisation but also on the wide variety of the Sb-I bond strengths and the different bridges formed by iodine.The lone pair of Sb(III) seems to be predominantly 5 s2.

Characterization of Several Microcrystalline Cellulose (MCC)-Based Agricultural Wastes via X-Ray Diffraction Method

2018 ◽  
Vol 280 ◽  
pp. 340-345 ◽  
Author(s):  
Muhammad Hanif Sainorudin ◽  
Masita Mohammad ◽  
Nurul Huda Abd Kadir ◽  
Nur Athirah Abdullah ◽  
Zahira Yaakob
Keyword(s):  
Sugarcane Bagasse ◽  
Microcrystalline Cellulose ◽  
Value Added ◽  
Crystallinity Index ◽  
Agricultural Wastes ◽  
X Ray Diffraction ◽  
X Ray ◽  
Coconut Coir ◽  
Pineapple Leaves ◽  
Banana Stem

In this study, microcrystalline cellulose (MCC) was extracted from various types of local agricultural wastes. Four types of agricultural waste such as coconut coir, banana stem, sugarcane bagasse and pineapple leaves were collected, extracted and hydrolyzed into microcrystalline cellulose, using pre-treatment (alkaline and bleaching) and acid hydrolysis, respectively. The extracted MCC were analyzed and compared with those of commercially available MCC. The study of crystallinity behaviors of the obtained MCC was performed by X-Ray Diffraction (XRD) analysis. The XRD of MCC revealed that the crystallinity of pineapple leaves has the highest crystallinity index with 75% in value and closest compared to commercial MCC, 81.25%. The value of crystallinity index for banana stem is 74.55% followed by coconut coir, 72.73% and sugarcane bagasse, 66.50%. All of the MCC samples showed the similar pattern with the typical crystalline structure of cellulose I. The crystallite size of all MCC samples was calculated and found in the range of 4.04 – 5.14 nm. These extracted MCC that obtained from several agricultural wastes was supposed to have a high potential as value-added products in industrial applications.

A coordination polymer of mercury(II) formed by triazole-based and chloride linkers

2017 ◽  
Vol 72 (8) ◽  
pp. 573-577 ◽  
Author(s):  
Seyed Ghorban Hosseini ◽  
Keyvan Moeini ◽  
Mohammed S.M. Abdelbaky ◽  
Santiago García-Granda
Keyword(s):  
Coordination Polymer ◽  
Three Dimensional ◽  
X Ray Diffraction ◽  
X Ray ◽  
Coordination Numbers ◽  
H Nmr ◽  
Square Planar ◽  
Polymeric Chains ◽  
Ft Ir ◽  
Hybrid Coordination

AbstractIn this work, a coordination polymer formed from 4,5-diamino-3-methyl-4H-1,2,4-triazol-1-ium chloride (DAMT·HCl) and HgCl2 formulated as [Hg5(μ-DAMT)2(μ-Cl)6(μ3-Cl)2Cl2]n has been prepared and characterized by elemental analysis, FT-IR, 1H NMR spectroscopy, and single-crystal X-ray diffraction. X-ray analysis of the complex revealed an organic-inorganic hybrid coordination polymer containing three different mercury atoms with coordination numbers of 4 (HgN(μ-Cl)2(μ3-Cl)), 5 (Hg(μ-Cl)3(μ3-Cl)Cl), and 6 (HgN2(μ-Cl)2(μ3-Cl)2) and seesaw, octahedral, and square pyramidal geometries, respectively. The polymeric chains are extended to a three-dimensional (3D) array by C–H···Cl and N–H···Cl interactions. In addition to these hydrogen bonds, there are Hg···Cl interactions with the mercury atoms with coordination numbers 4 and 5 to complete their pseudo-square planar and -octahedral geometries, respectively.

An Improved Method to Extract Crystalline Cellulose from Alternatives Sources

2017 ◽  
Vol 371 ◽  
pp. 128-130
Author(s):  
M. Sánchez ◽  
Mauro Cesar Terence ◽  
Juan Alfredo Guevara Carrió
Keyword(s):  
Diffraction Method ◽  
Crystallinity Index ◽  
Crystalline Cellulose ◽  
Cellulose Crystallinity ◽  
Improved Method ◽  
X Ray Diffraction ◽  
Waste Wood ◽  
X Ray ◽  
Alternative Sources ◽  
High Cellulose

Crystalline cellulose can be obtained from alternative sources like waste wood by hydrolysis with hydrochloric or sulfuric acid. In this study we report a process for producing crystals with high cellulose crystallinity index of approximately 82%. We chose to work with eucalyptus FSC certified as a way to ensure the reproducibility of experiments. Said wood samples were subjected to acid hydrolysis with nitric acid. The resulting mass was dried out and measured by the X-ray diffraction method.

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