Wide angle diffraction studies WAXS

Observations of infrared dichroism on pol3rmeric systems were first made about 1950 using pols peptides (53,54). Fraser (55,56) developed its use to measure orientation in polymers quantitatively and establish a relationship of dichroic ratio D to the Hermans orientation factor equivalent to equation 2. The first infrared dichroism studies on polyethylene were performed in 1954 by Stein and co-workers (57,58). The article (58) discusses the determination of uniaxial orientation in polyethylene films using wide-angle x-ray (wax) diffraction, birefringence, and infrared dichroism, and explicitly states the interrelation of the former two measurements through... 

PVC has a complex particle morphology and a low degree of crystallinity. The crystallinity of PVC increases with increase in syndiotacticity. The level of syndiotacticity rises with fall in the temperature of polymerisation, and in the case of commercial types of PVC-S reaches 54-56%, whereas their crystallinity is only about 10%. The presence of crystalline forms in PVC has been established by studies using e.g. small-angle x-ray scattering, wide-angle X-ray diffraction (WAXS), IR spectroscopy and differential scanning calorimetry (DSC). In PVC, crystallites are formed under conversion conditions of less than 2%. These... 

Synchrotron radiation based X-ray diffraction and scattering methods have found many uses in the study of structural developments of materials when exposed to external perturbations like pressure, chemical or mechanical changes. The well known method of powder X-ray diffraction (PXRD) or also Wide Angle X-ray Scattering (WAXS) hardly requires any introduction since it is a standard tool in many laboratories and we refer here to the many existing text books that describe the possibilities and limitations of this technique. ... 

The morphological structure of the butadiene-acetylene graft copolymer films was studied using TEM, electron diffraction and wide-angle X-ray scattering (WAXS). A series of the butadiene-acetylene copolymers with acetylene content ranging from 10 to 50 wt% and a cisitrans ratio from 70/30 to 10/90 was prepared [73]. Unreacted polybutadiene homopolymer was extracted from the copolymer samples in toluene... 

X-ray scattering techniques are the most commonly applied complementary discipline to microscopy for structural studies. The type of information that is obtained by x-ray scattering experiments includes phase identification and quantification, crystallinity, crystallite size, lattice constants, molecular orientation and structure, molecular packing and order, and amorphous structure [26-30]. Diffraction techniques that will be described include powder diffraction, wide angle x-ray scattering (WAXS), and fiber diffraction. Small angle x-ray scattering (SAXS) will be described in Section 7.4.4. 

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