scholarly journals Influence of Various Climatic Conditions on the Structural Changes of Semicrystalline PLA Spun-Bonded Mulching Nonwovens during Outdoor Composting

Polymers ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 559 ◽  
Author(s):  
Michał Puchalski ◽  
Piotr Siwek ◽  
Nicolay Panayotov ◽  
Małgorzata Berova ◽  
Stanisława Kowalska ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Structural Changes ◽  
Climatic Conditions ◽  
First Year ◽  
Wide Angle ◽  
Viscosity Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Second Year ◽  
Scanning Electron

This study analyzed the structural changes of semicrystalline polylactide (PLA) in the form of spun-bonded mulching nonwovens, during outdoor composting. The investigation was carried out at the microstructural, supramolecular and molecular levels using scanning electron microscopy (SEM), wide-angle X-ray diffraction (WAXD) and the viscosity method, respectively. The obtained experimental results revealed how the popular outdoor composting method, realized under two different European climatic conditions (in Poland and in Bulgaria), affects the degradation of PLA nonwoven, designed for agriculture use. The results showed the insignificant influence of the climatic conditions and prepared compost mixtures on the molecular and micromorphological structure of PLA spun-bonded mulching nonwovens, with a visible increase in crystallinity after the first year of composting. Significant changes were observed only after the second year of composting, which indicates the resistance of semicrystalline PLA to degradation in outdoor composting conditions.

scholarly journals Influence of Various Climatic Conditions on the Structural Changes of Semicrystalline PLA Spun-Bonded Mulching Nonwovens during Outdoor Composting

2019 ◽  
Author(s):  
Michał Puchalski ◽  
Piotr Siwek ◽  
Nicolay Panayotov ◽  
Małgorzata Berova ◽  
Stanisława Kowalska ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Climatic Condition ◽  
Degradation Rate ◽  
Structural Changes ◽  
Climatic Conditions ◽  
Wide Angle ◽  
Viscosity Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

This study analyzed the structural changes of semicrystalline polylactide (PLA) in the form of spun-bonded mulching nonwoven, during outdoor composting. The investigation was carried out at the microstructural, supramolecular and molecular levels using scanning electron microscopy (SEM), wide-angle X-ray diffraction (WAXD) and the viscosity method, respectively. The results showed the varying degree of influence of the climatic condition, prepared compost mixtures and time on the molecular, supramolecular and micromorphological structure of PLA spun-bonded mulching nonwoven and its degradation rate. The obtained experimental results revealed how the popular outdoor composting method, realized under two different European climatic conditions (in Poland and in Bulgary), affects the degradation of PLA nonwoven, designed for agriculture use.

Investigation of Biocomposites Containing Glycerol-Plasticized Soy Protein and Kaolin

2011 ◽  
Vol 287-290 ◽  
pp. 1712-1717
Author(s):  
Hua Feng Tian ◽  
Guo Zhi Xu ◽  
Biao Yang
Keyword(s):  
Electron Microscopy ◽  
Thermal Stability ◽  
Scanning Electron Microscopy ◽  
Soy Protein ◽  
Original Structure ◽  
Wide Angle ◽  
X Ray Diffraction ◽  
Protein Matrix ◽  
X Ray ◽  
Scanning Electron

A series of soy protein/kaolin nanocomposites have been successfully prepared via solution mixing and then extrusion. The structure and the properties of the nanocomposite plastics were characterized by wide-angle X-ray diffraction (WAXD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), water uptake as well as mechanical testing. WAXD revealed that the nano-sized kaolin filler in soy protein matrix retained the original structure as the pristine kaolin. In view of the results of SEM, kaolin distributed in the protein matrix homogeneously and exhibited fine adhesion with soy protein. The incorporation of kaolin into glycerol-plasticized soy protein led to great improvements of mechanical and water resistant properties. The thermal stability was also enhanced by the incorporation of kaolin as revealed by TGA characterization.

Synthesis of Ultra-Fine Conducting Polyaniline Micro/Nanotubes Using Fiber Template and Their NH3 Gas Sensitivity

2007 ◽  
Vol 7 (12) ◽  
pp. 4515-4521 ◽  
Author(s):  
Bo Xue ◽  
Shaoyan Qi ◽  
Jian Gong ◽  
Yu Gao ◽  
Shuang Yao ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Wide Angle ◽  
X Ray Diffraction ◽  
Gas Sensitivity ◽  
X Ray ◽  
Transmission Electron ◽  
Conducting Polyaniline ◽  
Inner Diameter ◽  
Scanning Electron

We have recently fabricated ultra-fine conducting polyaniline (PANI) tubes with high gas sensitivity. This route includes two steps. Firstly, aniline polymerizes on the surface of a suitable fiber template prepared by electrospun nitrocellulose (NC). Then, the NC fiber template is dissolved and the ultra-fine PANI tubes are obtained. The structure of the conducting PANI tubes is characterized by IR spectrum and wide-angle X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results indicate that the PANI shows the shape of ultra-fine tubes with average inner diameter of 250–350 nm. The wall thickness of the ultra-fine PANI tubes increases with increasing the content of oxidant. The conductivity of the doped PANI tubes is about 6 9 × 10−2 S. The results of gas sensitivity of the ultra-fine PANI tubes indicate that the PANI tubes can act as "electronic nose" to detect toxic NH3 gas below 20 ppm.

Annealing induced structural changes and microcracking in Mo-Mo3Si

2002 ◽  
Vol 753 ◽  
Author(s):  
X.-L. Wang ◽  
J. H. Schneibel ◽  
Y. D. Wang ◽  
J. W. Richardson
Keyword(s):  
Electron Microscopy ◽  
Experimental Data ◽  
High Temperature ◽  
Structural Changes ◽  
Thermal Stresses ◽  
Annealing Temperature ◽  
Composition Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

ABSTRACTCast Mo-Mo3Si intermetallic composites develop microcracks after annealing at high temperature. Neutron diffraction, x-ray diffraction, composition analysis, and scanning electron microscopy have been used to characterize the structural changes induced by annealing of Mo-Mo3Si. It is shown that the observed cracking cannot be attributed to differential thermal stresses that developed on cooling from the annealing temperature. Instead, the experimental data suggest that the cracks were initiated at high temperature, possibly due to diffusion of Si atoms from supersaturated α-Mo to Mo3Si.

scholarly journals Effect of hydrothermal treatment on the structure of an aluminosilicate polymer

2013 ◽  
Vol 11 (5) ◽  
pp. 782-789 ◽  
Author(s):  
Jaroslav Melar ◽  
Vratislav Bednarik ◽  
Roman Slavik ◽  
Miroslav Pastorek
Keyword(s):  
Electron Microscopy ◽  
Hydrothermal Treatment ◽  
Structural Changes ◽  
Polycondensation Reaction ◽  
X Ray Diffraction ◽  
Microscopy Imaging ◽  
X Ray ◽  
Crystalline Product ◽  
Amorphous Aluminosilicate ◽  
Scanning Electron

AbstractThe effect of hydrothermal treatment on the structure of an aluminosilicate polymer prepared by a polycondensation reaction between silicate and hydroxoaluminate in alkaline aqueous solution was studied. The structural changes were investigated using X-ray diffraction analysis, Fourier-transform infrared spectroscopy, scanning electron microscopy imaging and thermogravimetric analysis. The results indicated that the amorphous aluminosilicate polymer transformed into a crystalline product during the hydrothermal treatment at 145°C. The crystalline phase was identified as a mineral of the zeolite group, most likely phillipsite. This transformation required an alkaline environment during the hydrothermal treatment.

scholarly journals Effects of Organomontmorillonite Content on Morphology and Mechanical and Thermal Properties of Poly(2,6-dimethyl-1,4-phenylene oxide)/Polyamide-66 Nanocomposites

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Kunxiao Yang ◽  
Chunling Xin ◽  
Ying Huang ◽  
Lilong Jiang ◽  
Yadong He
Keyword(s):  
Electron Microscopy ◽  
Complex Viscosity ◽  
Mechanical And Thermal Properties ◽  
Wide Angle ◽  
X Ray Diffraction ◽  
Polyamide 66 ◽  
X Ray ◽  
Phenylene Oxide ◽  
Transmission Electron ◽  
Scanning Electron

The nanocomposites consisting of polymer matrix and nanofiller have attracted great attention because of the improved physical properties. In this paper, organomontmorillonite (OMMT) was introduced into poly(2,6-dimethyl-1,4-phenylene oxide) grafted maleic anhydride (PPO-g-MA) compatibilized poly(2,6-dimethyl-1,4-phenylene oxide)/polyamide-66 (PPO/PA66) blends by melt extrusion. The morphology of PPO/PA66 nanocomposites with different amounts of OMMT was investigated using transmission electron microscopy (TEM), wide-angle X-ray diffraction (WAXD), and scanning electron microscopy (SEM). The OMMT platelets exhibited an exfoliated structure in the PA66 matrix and an intercalated structure on the surface of PPO domains at low OMMT loading (2 phr). However, the exfoliated platelets in matrix were found to transform into intercalated stacks by adding 6 phr of OMMT. The mechanical properties and thermal stability were significantly improved with the coexistence of exfoliated and intercalated OMMT at low OMMT loading (2–4 phr). The exfoliated OMMT platelets imposed a confinement effect on the macromolecular chains and thereby increased the storage modulus and complex viscosity of nanocomposites.

Preparation of Cellulose Micro/Nano Fibrils by Sonochemical Method and its Morphological Characterization

2013 ◽  
Vol 562-565 ◽  
pp. 864-868
Author(s):  
Yan Wu ◽  
Zhi Hui Wu ◽  
Ji Lei Zhang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Morphological Characterization ◽  
Sonochemical Method ◽  
Wide Angle ◽  
Chemical Pretreatment ◽  
X Ray Diffraction ◽  
X Ray ◽  
Basic Characteristics ◽  
Scanning Electron

The eucalyptus cellulose micro/nano fibrils were prepared by using high intensity ultrasonication with chemical pretreatment. The basic characteristics of cellulose micro/nano fibrils were evaluated by wide-angle X-ray diffraction instrument (WAXD) and scanning electron microscopy (SEM).

Identification of calcium oxalate crystals in dried or fixed tobacco leaf

1984 ◽  
Vol 42 ◽  
pp. 288-289
Author(s):  
Vicki L. Baliga ◽  
Mary Ellen Counts
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Calcium Oxalate ◽  
Growth And Development ◽  
Polarized Light ◽  
Calcium Oxalate Crystals ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

Calcium is an important element in the growth and development of plants and one form of calcium is calcium oxalate. Calcium oxalate has been found in leaf seed, stem material plant tissue culture, fungi and lichen using one or more of the following methods—polarized light microscopy (PLM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and x-ray diffraction.Two methods are presented here for qualitatively estimating calcium oxalate in dried or fixed tobacco (Nicotiana) leaf from different stalk positions using PLM. SEM, coupled with energy dispersive x-ray spectrometry (EDS), and powder x-ray diffraction were used to verify that the crystals observed in the dried leaf with PLM were calcium oxalate.

Environmental scanning electron microscopy of fresh human gallstones reveals new morphologies of precipitated calcium salts

1992 ◽  
Vol 50 (2) ◽  
pp. 1322-1323
Author(s):  
Howard S. Kaufman ◽  
Keith D. Lillemoe ◽  
John T. Mastovich ◽  
Henry A. Pitt
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Environmental Scanning Electron Microscopy ◽  
Environmental Scanning ◽  
X Ray Diffraction ◽  
Calcium Salts ◽  
Cholesterol Gallstones ◽  
X Ray ◽  
Ca Carbonate ◽  
Scanning Electron

Gallstones contain precipitated cholesterol, calcium salts, and proteins. Calcium (Ca) bilirubinate, palmitate, phosphate, and carbonate occurring in gallstones have variable morphologies but characteristic windowless energy dispersive x-ray (EDX) spectra. Previous studies of gallstone microstructure and composition using scanning electron microscopy (SEM) with EDX have been limited to dehydrated samples. In this state, Ca bilirubinates appear as either glassy masses, which predominate in black pigment stones, or as clusters, which are found mostly in cholesterol gallstones. The three polymorphs of Ca carbonate, calcite, vaterite, and aragonite, have been identified in gallstones by x-ray diffraction, however; the morphologies of these crystals vary in the literature. The purpose of this experiment was to study fresh gallstones by environmental SEM (ESEM) to determine if dehydration affects gallstone Ca salt morphology.Gallstones and bile were obtained fresh at cholecystectomy from 6 patients. To prevent dehydration, stones were stored in bile at 37°C. All samples were studied within 4 days of procurement.

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