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Properties of a branched polyester ether as a function of the preparation method
Author(s) -
Fagerburg D. R.
Publication year - 1985
Publication title -
polymer engineering and science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.503
H-Index - 111
eISSN - 1548-2634
pISSN - 0032-3888
DOI - 10.1002/pen.760251310
Subject(s) - condensation polymer , materials science , polyester , molar mass distribution , ether , polymer , polymer chemistry , monomer , crystallization , intrinsic viscosity , viscosity , chemical engineering , composite material , organic chemistry , chemistry , engineering
Properties of a branched polyester ether elastomer have been examined by using two widely differing preparation methods: (1) prepared to final molecular weight by using melt polycondensation (MP) and (2) prepared to an intermediate molecular weight by using melt polycondensation followed by solid phase polycondensation to the final molecular weight (SP). Differences in T m were attributed to annealing during the SP process and also to apparent changes in monomer sequence distribution in the polymer chains. Crystallization during cooling (DSC) and melt viscosity appeared to be solely a function of molecular weight rather than of preparation history. Molecular weight distribution was exponentially dependent on viscosity average molecular weight for the MP samples, but the distribution was linearly dependent for the SP case which more nearly represents equilibrium conditions. Polymer mechanical properties did not vary much in spite of the pronounced differences observed.