ZUSAMMENFASSUNG:Es wird gezeigt, wie aus Messungen der Winkelabhangigkeit der Linienbreite in Rontgenweitwinkeldiagrammen von Hochpolymeren die KristallitgroDe und die Gitterstorungen bestimmt werden konnen. I n losungskristallisierten linearen Polyathylenen treten rein parakristalline Gitterstorungen auf, die thermodynamisch stabil sind. Verzweigtes Polyathylen zeigt mit dem Verzweigungsgrad anwachsende Gitterstorungen und abnehmende KristallitgroDen. I m schmelzkristallisierten linearen Polyathylen werden Spannungen beobachtet ; die Werte der KristallitgroDen sind teilweise erheblich hoher als im losungskristallisierten Material. I n Kettenrichtung sind die Gitterstorungen wesentlich kleiner als senkrecht dam. Kombination von Rontgenmessungen mit anderen Untersuchungsmethoden (ESR, NMR, Suszeptibilitat, ReiDfestigkeit) geben die Moglichkeit, genauere Einblicke in den Verstreck-und ReiDvorgang zu gewinnen. SUMMARY:A method is given to calculate the crystallite sizes and lattice distortions in high polymers from the measurement of the variation of line width with scattering angle in X-ray diagrams. Solution crystallized linear polyethylene shows thermodynamic stable paracrystalline distortions. I n branched polyethylene the distortions increase and the crystallite size decreases with higher degree of branching. I n melt crystallized linear polyethylene distortions of the strain type are found, the crystallite sizes sometimes are much higher than in solution grown crystals. The lattice distortions in the direction of the chain are much lower than perpendicular to the chain. The combination of X-ray measurements with other rqethods (ESR, NMR, susceptibility, rupture strength) allows a better understanding of %%e mechanism of stretching and rupture Einleitung

Polystyrene films have been grafted by radical polymerization in situ on the surface of glass slides. The morphology of these films resulting from different grafting temperatures has been investigated by both the contact angle method and scanning probe microscopy with respect to the grafting time. At a grafting density regime where the theory proposes the existence of a homogeneous layer, the formation of island structures of grafted polymer with a size substantially higher than expected by the theory has been observed. Overshot polymer structures of large sizes are created. The amount of grafted polymer is substantially higher than that predicted from the conception of monolayer covering. The grafting layer becomes impermeable for water only at a high amount of grafted polymer, which corresponds to the multilayer structure of the coating. We suggested a mechanism for the grafting process that included at least three stages:  (a) first, a brushlike polymer layer is formed; (b) subsequently, a second layer of ungrafted chains is created in the regime when excess chains are forced out from the first layer; (c) big polymer clusters, with an average size of 100−200 nm due to gel polymerization in the clusters, formed in the force out regime.

A three-dimensional monoclinic paracrystalline macrolattice is used to calculate the small angle X-ray scattering pattern of partially oriented polymers with rotational symmetry about the fiber axis. The influence of the crystallite size, the lattice parameters, the lattice distortions and the orientation relative to the fiber axis on the diffraction patterns is studied.

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