Published : 2020-02-28

Synthesis and properties of new polyurethane elastomers: influence of hard segment structure

Abstract

Two series of poly(ester urethane) (PUR) elastomers, containing poly(?-caprolactone) diol of Mn=2000 as soft segments were synthesized. In each series the same diisocyanate in hard segment, i.e., 1,6-hexamethylenediisocyanate was used in the same content. The PUR polymers were prepared in two-step polymerization in the absence of a catalyst; the molar ratio of OHpolyol/NCO/OHchain extender was 1/2/1. The chain extenders were 1,4-cyclohexane diol, 1,4-bis(hydroxymethyl)cyclohexane diol, glycerin or castor oil. The structures of all polymers were determined by FTIR, the physico-chemical and thermal properties were determined by differential scanning calorimetry and by thermogravimetry and additionally tensile properties were analyzed. Poly(ester urethane)s with 1,4-cyclohexane diol exhibited higher tensile strength (up to 16MPa vs 13MPa) and elongation at break (up to ~780% vs. 600%) in comparison with the corresponding poly(ester urethane)s based on 1,4-bis(hydroxymethyl)cyclohexane diol. A decrease in the chain length between crosslinking points was accompanied by an increase in thermal stability. Tensile strength can be attributed to a relatively dense crosslinking network and strong intermolecular hydrogen bonding.


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Oprea, S. (2020). Synthesis and properties of new polyurethane elastomers: influence of hard segment structure. Polimery, 55(2), 111-117. Retrieved from http://ichp.vot.pl/index.php/p/article/view/993