Computer Capability for the Determination of Polymer Crystallinity by X-Ray Diffraction

1985 ◽  
Vol 29 ◽  
pp. 281-290
Author(s):  
Andrew M. Wims ◽  
Mark E. Myers ◽  
Jack L. Johnson ◽  
Julia M. Carter
Keyword(s):  
Room Temperature ◽  
Physical And Mechanical Properties ◽  
Degree Of Crystallinity ◽  
X Ray Diffraction ◽  
Percent Elongation ◽  
X Ray ◽  
Reinforcing Fillers ◽  
Crystalline Domains ◽  
Polymer Crystallinity

The physical and mechanical properties of many industrially important polymers are profoundly influenced by their degree of crystallinity; such properties include flex modulus, tensile strength, percent elongation, and impact strength. Commonly used polymers influenced by their crystallinity level include polyethlene, polypropylene, polyesters, and nylons. Many of these materials are above their glass transition temperature at room temperature and would be useless were it not for their crystalline phase which typically has a melting point far above room temperature. The crystalline ‘ regions (domains) in these materials are frequently very small, typically in the nanometer range in diameter. These crystalline domains act as reinforcing fillers (in somewhat the same manner as carbon black In rubber) and give strength to the polymer.

Physical and Mechanical Properties of Cement Paste Were Used Partially with Fly Ash and Kaolin Waste

2017 ◽  
Vol 866 ◽  
pp. 199-203
Author(s):  
Chidchanok Chainej ◽  
Suparut Narksitipan ◽  
Nittaya Jaitanong
Keyword(s):  
Mechanical Properties ◽  
Fly Ash ◽  
Room Temperature ◽  
Physical And Mechanical Properties ◽  
Partial Replacement ◽  
X Ray Diffraction ◽  
X Ray ◽  
Lime Water ◽  
Diffraction Patterns ◽  
Iron Mold

The aims of this research were study the microstructures and mechanical properties for partial replacement of cement with Fly ash (FA) and kaolin waste (KW). Ordinary Portland cement were partially replaced with FA and KW in the range of 25-35% and 10-25% by weight of cement powder. The kaolin waste was ground for 180 minutes before using. The specimen was packing into an iron mold which sample size of 5×5×5 cm3. Then, the specimens were kept at room temperature for 24 hours and were moist cured in the incubation lime water bath at age of 3 days. After that the specimens were dry cured with plastic wrap at age of 3, 7, 14 and 28 days. After that the compounds were examined by x-ray diffraction patterns (XRD) and the microstructures were examined by scanning electron microscopy (SEM). The compressive strength was then investigated.

Interface and Volume Anisotropy of MBE-Grown Co/Pt (111), (110) and (001) and Sputtered CO/Pt Multilayers

1993 ◽  
Vol 313 ◽  
Author(s):  
D. Weiler ◽  
R.F.C. Farrow ◽  
R.F. Marks ◽  
G.R. Harp ◽  
H. Notarys ◽  
...  
Keyword(s):  
Room Temperature ◽  
Good Accuracy ◽  
Anisotropy Constant ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gaas Substrates ◽  
Plane Anisotropy ◽  
Plane Direction ◽  
Total Average

ABSTRACTA quantitative determination of interface (Ks) and volume anisotropy {?ψ) constants of MBE and sputtered CO/Pt Multilayers is reported. Torque and VSM Magnetometry were used to determine the total average anisotropy and the room temperature magnetization of four different series of films with varying Co thickness and nearly constant Pt thickness. All films were characterized with X-ray diffraction and X-ray fluorescence, allowing the determination of the “Magnetic” volume with good accuracy. Both Ks and Jeff are found to be orientation dependent. We find the following results for MBE films grown on Ag buffered GaAs substrates and highly < 111 > textured films, grown on etched SiNx buffers:(111) Ks = 0.97mJ/m2, Kveff =-0.74MJ/m3 MBE(111) Ks = 0.92mJ/m2, Kveff =-l.lIMJ/m3 sputtered(110) Ks = 0.42mJ/m2, Kveff =-l.95MJ/m3 MBE(001) Ks = 0.59mJ/m2, Kveff =-5.98MJ/m3 MBEThe [110]-oriented MBE films show in addition a large (intrinsic) in-plane anisotropy constant K‖0≃-3MJ/m3 which is found to be independent of the Co thickness. [100] is the easy and [110] the hard in-plane direction.

Determination of the cationic distribution in oxidic thin films by resonant X-ray diffraction: the magnetoelectric compound Ga2−xFexO3

2016 ◽  
Vol 49 (4) ◽  
pp. 1308-1314 ◽  
Author(s):  
Christophe Lefevre ◽  
Alexandre Thomasson ◽  
Francois Roulland ◽  
Vincent Favre-Nicolin ◽  
Yves Joly ◽  
...  
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Element Distribution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Site Distribution ◽  
X Ray Scattering ◽  
Cationic Distribution ◽  
Cationic Site

The cationic distribution is decisive for both the magnetic and electric properties of complex oxides. While it can be easily determined in bulk materials using classical methods such as X-ray or neutron diffraction, difficulties arise for thin films owing to the relatively small amount of material to probe. It is shown here that a full determination of the cationic site distribution in thin films is possible through an optimized processing of resonant elastic X-ray scattering experiments. The method is illustrated using gallium ferrite Ga2−xFexO3samples which have been the focus of an increasing number of studies this past decade. They indeed represent an alternative to the, to date, only room-temperature magnetoelectric compound BiFeO3. The methodology can be applied to determine the element distribution over the various crystallographic sites in any crystallized system.

scholarly journals Determination of the Degree of Crystallinity of Poly(2-methyl-2-oxazoline)

Polymers ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 4356
Author(s):  
Evgeniy M. Chistyakov ◽  
Sergey N. Filatov ◽  
Elena A. Sulyanova ◽  
Vladimir V. Volkov
Keyword(s):  
Thermal Destruction ◽  
Polymer Melt ◽  
Boron Trifluoride Etherate ◽  
Degree Of Crystallinity ◽  
X Ray Diffraction ◽  
X Ray ◽  
X Ray Scattering ◽  
Cationic Ring Opening Polymerization ◽  
The Degree Of Crystallinity

A new method for purification of 2-methyl-2-oxazoline using citric acid was developed and living cationic ring-opening polymerization of 2-methyl-2-oxazoline was carried out. Polymerization was conducted in acetonitrile using benzyl chloride—boron trifluoride etherate initiating system. According to DSC data, the temperature range of melting of the crystalline phase of the resulting polymer was 95–180 °C. According to small-angle X-ray scattering and wide-angle X-ray diffraction data, the degree of crystallinity of the polymer was 12%. Upon cooling of the polymer melt, the polymer became amorphous. Using thermogravimetric analysis, it was found that the thermal destruction of poly(2-methyl-2-oxazoline) started above 209 °C.

Investigation into the Crystal Structure of the Perovskite Lead Hafnate, PbHfO3

1998 ◽  
Vol 54 (1) ◽  
pp. 18-28 ◽  
Author(s):  
D. L. Corker ◽  
A. M. Glazer ◽  
W. Kaminsky ◽  
R. W. Whatmore ◽  
J. Dec ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Room Temperature ◽  
Lead Zirconate ◽  
Crystal Structure Analysis ◽  
Temperature Structure ◽  
X Ray Diffraction ◽  
Neutron Data ◽  
X Ray

The room-temperature crystal structure of the perovskite lead hafnate PbHfO3 is investigated using both low-temperature single crystal X-ray diffraction (Mo Kα radiation, λ = 0.71069 Å) and polycrystalline neutron diffraction (D1A instrument, ILL, λ = 1.90788 Å). Single crystal X-ray data at 100 K: space group Pbam, a = 5.856 (1), b = 11.729 (3), c = 8.212 (2) Å, V = 564.04 Å3 with Z = 8, μ = 97.2 mm−1, F(000) = 1424, final R = 0.038, wR = 0.045 over 439 reflections with F >1.4σ(F). Polycrystalline neutron data at 383 K: a = 5.8582 (3), b = 11.7224 (5), c = 8.2246 (3) Å, V = 564.80 Å3 with χ2 = 1.62. Although lead hafnate has been thought to be isostructural with lead zirconate, no complete structure determination has been reported, as crystal structure analysis in both these materials is not straightforward. One of the main difficulties encountered is the determination of the oxygen positions, as necessary information lies in extremely weak l = 2n + 1 X-ray reflections. To maximize the intensity of these reflections the X-ray data are collected at 100 K with unusually long scans, a procedure which had previously been found successful with lead zirconate. In order to establish that no phase transitions exist between room temperature and 100 K, and hence that the collected X-ray data are relevant to the room-temperature structure, birefringence measurements for both PbZrO3 and PbHfO3 are also reported.

FEATURES OF X-RAY ANALYSIS OF CRYSTALLINITY DEGREE OF POLYPROPYLENE FIBRES

2018 ◽  
Vol 59 (7) ◽  
pp. 80 ◽  
Author(s):  
Aleksandr Ye. Zavadskii
Keyword(s):  
Degree Of Crystallinity ◽  
X Rays ◽  
Ray Method ◽  
Polypropylene Fibres ◽  
Crystallinity Degree ◽  
X Ray ◽  
Diffuse Halo ◽  
Standard Powder ◽  
Polymer Crystallinity

The need to take into account the anisotropy of compact samples pressed from grinded polypropylene (PP) fibres at a determination of the degree of polymer crystallinity by X-ray method was shown. It was proved that the breach of the spherical scattering symmetry of X-rays by PP fiber samples is not connected with an amorphous phase of polymer. The method for calculating the degree of crystallinity of fibres from the normalized intensity of the diffuse halo of preparations under study and standard powder PP samples was proposed.

Digital Filtering and Shape Identification in the Analysis of WAXD Patterns of Semicrystalline Polymers

2013 ◽  
Vol 203-204 ◽  
pp. 189-192 ◽  
Author(s):  
Małgorzata Rabiej
Keyword(s):  
Numerical Differentiation ◽  
Degree Of Crystallinity ◽  
X Ray Diffraction ◽  
Amorphous Halo ◽  
Shape Identification ◽  
Diffraction Curve ◽  
X Ray ◽  
The Degree Of Crystallinity ◽  
Quick Determination

Most frequently, the degree of crystallinity of polymers is determined using Wide Angle X-ray Diffraction (WAXD) technique. The method consists in the resolution of WAXD diffraction curve of a polymer into individual crystalline peaks and amorphous halo. This work presents a procedure, which was elaborated to help in a quick determination of the angular positions of crystalline peaks present in the diffraction curve of investigated polymer. The positions of peaks are determined using numerical differentiation. Using these data the computer program WAXSFIT identifies investigated polymer and prepares a set of starting parameters which are used in the calculations of the degree of crystallinity.

Magnetic and Microstructural Aspects of the Bulk Metallic Glassy Materials Nd60Fe30Al10

2001 ◽  
Vol 674 ◽  
Author(s):  
N. H. Dan ◽  
N. X. Phuc ◽  
V. H. Ky ◽  
N. M. Hong ◽  
N. Chau ◽  
...  
Keyword(s):  
Room Temperature ◽  
Amorphous Material ◽  
Magnetic Hysteresis ◽  
Degree Of Crystallinity ◽  
Nominal Composition ◽  
X Ray Diffraction ◽  
Cast Sample ◽  
X Ray ◽  
Glassy Materials ◽  
Ferromagnetic Bulk

ABSTRACTThe ferromagnetic bulk metallic glass (BMG) Nd60Fe30Al10system exhibits extremely large coercivities at low temperature and moderate coercivities near room temperature. The magnetic hardness, as best evidenced by the onset of magnetic irreversibility, was studied in bulk suction-cast and melt-spun alloys with the nominal composition Nd60Fe30Al10. Systematic x-ray diffraction studies of the degree of crystallinity performed as a function of position within the bulk suction-cast samples is found to correlate with the variation in the room-temperature magnetic hysteresis character. X-ray diffraction data clearly shows the presence of both crystallites and amorphous material on the samples' outmost surfaces; the amorphous phase content increases with distance into the cast sample. These results underscore the importance of solidification conditions and attendant nanophase selection, on the resultant magnetic properties of this class of alloys.

High-precision absolute lattice parameter determination of SrTiO3, DyScO3 and NdGaO3 single crystals

2012 ◽  
Vol 68 (1) ◽  
pp. 8-14 ◽  
Author(s):  
Martin Schmidbauer ◽  
Albert Kwasniewski ◽  
Jutta Schwarzkopf
Keyword(s):  
High Resolution ◽  
High Precision ◽  
Room Temperature ◽  
Systematic Errors ◽  
Lattice Parameter ◽  
Parameter Determination ◽  
X Ray Diffraction ◽  
X Ray ◽  
Bond Method

The lattice parameters of three perovskite-related oxides have been measured with high precision at room temperature. An accuracy of the order of 10−5 has been achieved by applying a sophisticated high-resolution X-ray diffraction technique which is based on the modified Bond method. The results on cubic SrTiO3 [a = 3.905268 (98) Å], orthorhombic DyScO3 [a = 5.442417 (54), b = 5.719357 (52) and c = 7.904326 (98) Å], and orthorhombic NdGaO3 [a = 5.428410 (54), b = 5.498407 (55) and c = 7.708878 (95) Å] are discussed in view of possible systematic errors as well as non-stoichiometry in the crystals.

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