R. Ukielski, New multiblock terpoly(ester-ether-amide) thermoplastic elastomers with various chemical composition of ester block, POLYMER, 41(5), 2000, pp. 1893-1904
New block terpolymers of the poly[oxytetramethylene-block-(multi-meth terep
hthalate)-block-laurolactam] (aGT-b-PO4-b-PA12) with potential applications
as elastomers have been obtained by melt polycondensation of dimethyl tere
phthalate or isophthalate (DMT, DMI), glycols (aG), poly(oxytetramethylene)
diol (PO4, M-w approximate to 1000 g mol(-1)) and alpha,omega-dicarboxylic-
oligolaurolactam (PA12 approximate to 2250 g mol(-1)). The degree of polyco
ndensation (DP) of poly(multi-methylene terephthalate) aGT amounts to DPGT
= 4 The influence of the number of carbons (a) separating the terephthalate
groups as well as meta or para positions of the ester groups in the benzen
e ring of other blocks, on the synthesis, properties and structure of these
elastomers have been evaluated. The influence of changes in chemical compo
sition of ester block (GT) on the structure and thermal and mechanical prop
erties of the terpolymers have been determined by differential scanning cal
orimetry (DSC), dynamic mechanical thermal analysis (DMTA), wide-angle X-ra
y diffraction (WAXS) and other standard physical methods. The properties of
aGT-b-PO4-b-PA12 depend upon the mutual interaction of PA12 blocks with PO
4 blocks, whereas aGT with PO4 and aGT with PA12, respectively. The charact
eristic properties of the aGT-b-PO4-b-PA12 terpolymers is the large content
of the interphase (w(iph) > 40%). The fraction of the interphase is depend
ent on the compatibility of aGT with PA12 blocks. The terpolymers prepared
with the use of 3G and 4G exhibit the highest content of interphase. Howeve
r, the 4GI-b-PO4-b-PA12 terpolymer has the highest degree of soft phase sep
aration. (C) 1999 Elsevier Science Ltd. All rights reserved.