Bw. Jo et al., TRANSESTERIFICATIONS IN A POLYBLEND OF POLY(BUTYLENE TEREPHTHALATE) AND A LIQUID-CRYSTALLINE POLYESTER, Polymer engineering and science, 35(20), 1995, pp. 1615-1620
Transesterification between a liquid crystalline polyester and poly(bu
tylene terephthalate) was followed quantitatively by analyzing C-13-NM
R spectra of the 50:50 blend after heat treatment at 290 degrees C for
varying lengths of time. Differential scanning analysis was employed
to follow the interchange reactions. From analysis of triad sequences
of the transesterified blends, it was clear that measurable exchange r
eactions occurred when the blend was kept at 290 degrees C for 20 min.
The distribution of sequences tends to approach that of a statistical
binary copolymer as the heat: treatment period is Increased. The resu
lts obtained from this investigation show that polyblends between an L
C polyester and conventional polyesters must be handled carefully. Oth
erwise, ester interchange reactions are inevitable.