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irregularly, as packing of macromolecules and growth of crystals are controlled by local
mobility of macromolecules elements near growing surface of the crystal [295].
Figure 3.3. Spectra of absorption of dye solutions HC-1 (1) and PETP dyed by this dye before (2) and
after (3) spinneret in cresol.
Space between microcrystals is filled by uncrystallizable part of polymer substance,
which grouts microcrystals combining them into fibrills. Fibrills are fibered structures
beginning in the centre of the crystal and being oriented radially. These are fibrils which
organize lamellae and provide their radial orientation.
Monocrystals (lamellae) and fibrils, in their turn, are being organized into larger
structural elements - spherulites. Lamellae are organized in spherulite in such a way that they
line up along radial directions from the centre of spherulite.
Amorphous region is formed from polymer parts, which do not crystallize because of
unfavourable location of segments.
If crystalline sectors contain PETP macromolecules in which groups -O-CH2-CH2-O-
are in transconfiguration, then in amorphous part this group is both in trans- and
cysconfiguration.
Amorphous phase of polymer is concentrated between crystals, fibrils and spherulites. It
consists of loops of different length, adhesions, passing chains of different length and
intensity, chains ends, uncrystallizable macromolecules or their sectors, containing branches,
stereochemical defects and irregularities in molecular structure. Lowmolecular fractions,
impurities of lowmolecular substances and so on are displaced into amoephous part of
polymer during the motion of crystallization frout. During copolymers crystallization
amorphous part is composed from sequences of component monomer links, incapable to
regular laying and crystallization.
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