Composition, hydrogen bonding and viscoelastic properties correlation for ethylene/α,ω-alkenol copolymers

Abstract

The influence of composition of ethylene/ α,ω -alkenol ( α,ω -alkenol = 10-undecen-1-ol or 9-decen-1-ol) copolymers on comonomer distribution and dynamic rheological properties were investigated. Thermal fractionation revealed formation of multiple peaks corresponding to the presence of methylene sequences of different length in copolymers. The share of fraction with shorter methylene sequence increased with increasing comonomer content. It turned out that viscoelastic behavior of ethylene/ α,ω -alkenol copolymers was dependent on comonomer content incorporated into the polymer chain. The relaxation time of reptation increased with increasing comonomer content what confirmed that comonomer units acted as physically crosslinking agent. FT-IR investigation proved the appearance of inter- and intramolecular hydrogen bonds in ethylene copolymers with α,ω -alkenols. Higher relative content of inter- and intramolecular hydrogen bonds was observed in α,ω -alkenol with a longer hydrocarbon chain. In addition, activation energy of flow increased with increasing of the comonomer content. Moreover, incorporation of α,ω -alkenols into the polymer chain resulted in a decrease of the packing length of copolymers with increasing comonomer content, what proved that the inter- and intramolecular hydrogen bond played a significant role in viscoelastic properties. • Amount of α,ω -alkenol incorporated in copolymers affected comonomer distribution. • The content of α,ω -alkenol played a key role in rheological behavior of copolymers. • The FT-IR study showed the presence of hydrogen bonds in E/ α,ω -alkenol copolymers. • The effect of hydrogen bonding is dependent on structure of α,ω -alkenol comonomer.