The free volume concept is indicated and the classical method of glass transition method are mentioned showing their limitations. Particular attention is paid to small angle X-ray scattering and positron annihilation spectroscopy of which some basic description is presented. These two last techniques are critically compared.

Three polypropylene films of constant thickness (approximately equals 50(mu) m) and different morphology were studied with use of an polarizing microscope, slow positron annihilation lifetime technique, wide and small angle X- ray scattering and attenuated total reflection of infrared radiation. Correlation was observed between the intensities of the intermediate components in the positron lifetime spectra; (lifetimes (tau) ₂ equals 1.3 ns and (tau) ₃approximately equals 2.3divided by2.8ns) and crystallinity of samples. The evident trend is for the longer-lived (tau) ₃-component intensity to decrease with crystallinity while the reverse is true for the shorter, fixed (tau) ₂-component. The decrease in the intensity of the longer-lived component can result from reduction of the fractional free volume. Changes of annihilation parameters with the positron penetration depth were observed that may reflect the spatial heterogeneity of samples resulting form the way of their crystallization and possible oxidation of the subsurface regions.

A direct method for the data evolution in the field of Small-Angle Scattering experiments including the discussion of a special procedure for the reduction of truncation errors is presented. The interface distribution function IDF, introduced by Ruland & Steibeck, can be considered as a starting point of data evaluation. The correlation function and the interface distribution are connected to a differential equation of third order.

Correlation function analysis on the SAXS profiles for ionomers containing alkali metals based on copolymers of styrene-acrylic acid and styrene-methacrylic acid obtained in emulsion are presented. The analysis was performed based on the liquid-like model of ionomer structure introduced by Yarusso and Cooper. A study has been made on the influence of content, type of salt and type of alkali metal in styrene- based ionomers on the state of ion aggregation. In all cases the state of ion aggregation is independent on the content of introduced acrylate or methacrylate and is dependent type of introduced alkali metal. The obtained results indicate that in the case of ionomers containing cesium acrylate aggregates of larger sizes are formed than containing cesium methacrylate. For all investigated ionomers the increase of temperature causes the increase of sizes and volume fraction of clusters.

WAXS diffraction was applied in studies of the effect of heavy ion irradiation on the content of crystalline phase in poly(ethyleneterephthalate) (PET) and poly(butyleneterephthalate)(PBT) films. A decrease of the crystalline phase content in PET and PBT films under the effect of heavy ions irradiation was discovered. The phenomenon was observed in the biaxially oriented 19 (mu) m thick PET film as well as in the non-oriented 90-100 (mu) m thick PET and PBT films. The amorphization of the films was confirmed by SAXS, DSC, and FTIR methods as well as by density measurements.

The description of the poly(4-methyl-1-pentene) films structure based on WAXS data is presented. The main object of this study are the opaque and transparent films obtained by casting on glass and teflon plates the solution of 2% (4%) PMP in cyclohexane or carbon tetrachloride. The films exhibiting a different supermolecular structure (the different size and shape of dendrites) were under consideration. The forming conditions of such forms, which look like diffusion limited aggregates, are presented.

Short flax fibres as the reinforcing material to PP/flax composite were mercerized and modified by silane compounds. Polymorphism transformation in the crystal structure of cellulose as an effect of chemical treatment of flax fibres was studied by means of wide-angle X-ray scattering (WAXS) method. It was found that after mercerization process only a part of cellulose I was transformed into cellulose II and silane treatment does not change the structure of the flax fibres. In the paper, based on WAXS measurement, a method of defining the amount of the cellulose I and the cellulose II was proposed.

Crystallization plays important role determining structure and morphology of a polymer subjected to processing. Due to the nature of technological processes, variation of external conditions like pressure, temperature, etc. occurs during crystallization. Understanding of nonisothermal crystallization processes is therefore crucial for designing and optimization of technological processes leading to materials and commodities possesing required properties. The present paper reports results of X-ray diffraction studies on kinetics of i- polypropylene crystallization occuring during linear cooling with various rates. Application of synchrotron as a source of radiation enables time-resolved measurements and evaluation of kinetic characteristics directly from quantities related to the developing structure of the polymer.

The structure and other physical properties of conjugated polymers are intensively studied in leading laboratories, due to the extremely interesting applicational perspectives of this class of materials. Among others, polyaniline and its derivatives are still in the center of interest of physics and chemistry polymers. Polyaniline in its protonated (conducting) form, like other polymers of this type, exhibits the X-ray diffraction patterns typical of semi-crystalline samples. The reasonable results concerning the crystalline structure of such low- ordered material can be obtained only by computer modelling of its structure. Choice of the solvent as well as the protonating agent has the great impact on the structural and electrical transport properties of the sample. For example, polyaniline films protonated with camphorsulfonic acid and casted from m-cresol exhibit the temperature dependence of electrical conductivity typical of metallic-like material. The structure of this polymer is still not known; however, we have obtained recently some interesting results in this field. Polyaniline may be significantly modified, in order to obtain a polymer characterized by expected properties. For example, poly(azomethines) or polyimines exhibit interesting catalytic properties, when they are doped with catalytically active species. In thsi work, the crystalline structures of unsubstituted poly(azomethine) and poly(azomethine) metoxysubstituted in the aromatic ring were determined by the X-ray diffraction method and the computer modelling. The diffraction patterns calculated for the models are almost identical as the crystalline components of the experimental diffraction patterns' also, the calculated densities are in good agreement with their experimental values. Such situation enables us to assume, that our models may be treated as the good approximation of the real crystalline structures of the polymers studied.

Time-resolved SAXS and SAXS/WAXS experiments were exploited to monitor the development of lamellar microstructure and crystallinity in neat poly(ethylene oxide) (PEO) and its blends with melt-miscible amorphous poly(methyl methacrylate) (PMMA). The low-molecular-weight fractions of PEO (Mw 3000) and of PMMA (Mw 1170, 3100, 3950) were used. Such PEO fraction crystallizes in the lamellae with extended (EC) or integrally folded (IF) chains. It has been found that in early stages of crystallization, transient NIF lamellae of PEO were formed in a wide range of compositions and temperatures similarly to the situation in neat PEO. Subsequent transformation of these lamellae into the lamellae with once-folded chains (1F) or EC occurred through isothermal thickening and thinning. The amorphous diluent has played a decisive role in structure development. The thickening prevailed in blends with high contents and high molecular weight of PMMA and at high crystallization temperature, the induction time of crystal formation increased, whereas the rates of NIF, 1F and EC crystallization and at the start and rate of the NIF structure recrystallization decreased. The retardation effect of amorphous diluent on the kinetics of these processes resulted in tendency to form gradually more stable and more perfectly ordered lamellar structures.

Plastic deformation of several blends including PE/PS, PE/SEBS/PS, PA6/PP-g-AA and iPP/HOCP, and resulting textures were studied using X- ray pole figures technique. The primary deformation mode chosen for this study was plane-strain compression in channel-die. Deformation in this mode is not accompanied by cavitation, which allows high strain deformation and helps to identify the deformation mechanisms active. It was found that the basic mechanisms of plastic deformation are crystallographic slips within lamellae supported by plastic shear and flow of amorphous component (intralamellar sliding). The mechanism identified are basically the same as those active in deformation of plain polymers. In phase separated blends interfaces between components do not cavitate and preserve their integrity in either uncompatibilzed or compatibilized blends. The inclusions of the second component influence the plastic deformation of the crystalline matrix by local modification of the stress field in their surroundings. That modification depends on the ratio of compliances of the inclusions and the matrix at the temperature of deformation.

The aim of the reported paper was to investigate the phase separation in liquid crystal olygomers and HDPE blends. A liquid crystalline compounds having three rings rod-like mesogen and aliphatic end groups has been synthesised. The blend of olygoesters and HDPE were obtained from solution. The supermolecular structure of olygoesters and blends was determined by SAXS and WAXS method. The thickness of the diffuse phase boundary has been obtained by means of Vonk's method. The small value of the transition layer between phases with the different electron density indicates low ability to phase separation.

The small-angle X-ray scattering method is shown to be very useful tool in studies of nanoporous materials. The correlation between the profiles of SAXS curves and the structure of dry gels is analysed in detail. The scattering methods afford the ability to obtain quantitative data on nanomorphology not available by other means. Investigations focus on conventional dry gels, sol-gel xerogels and aerogels.

The paper presents the small angle X-ray scattering (SAXS) studies of series of controlled porosity glasses (CPGs) with a polymer layer deposited on their surface which was obtained by crosslinking a dextran- polyimine mixture. For the investigated systems the power law scattering conditions (I(q)=I(subscript 0)q(superscript -(alpha) ), where I(subscript 0) and (alpha) are the constants, q- scattering vector) are fulfilled in a broad range of q values. The (alpha) value in the range 4<(alpha) <6 can result from the diffuse profile of the electron density in the boundary layer (transition layer) existing between the regions of different electron densities. For the investigated samples the values of (alpha) exponent change according to amounts of polymer in samples on the range 3.97- 4.49. Thus, the thickness of the transition layer for samples with (alpha) greater than 4.0 was calculated. The correlation between the amount of dextran or polyimine or crosslinking agent (diethyleneglycol diglycidyl ether) and the thickness of the transition layer was observed. Also, the comparison of the surface areas of CPGs with surface polymer layer measured by means of SAXS and BET method was examined. The obtained results demonstrate that the use of the equation [J(q)=k(subscript 1)/q + k(subscript 2)/q$=3)] in SAXS calculations results in SAXS surface areas comparable with those from BET measurements. In addition, the differences between them depend on the transition layer surface also explains the distinctions between the ion capacity of sorbents and the concentration of electron - donor nitrogen atoms existing in the investigated materials.