Structural properties of tung oil-based polymers: Influence of the type of co-monomer on the free volume and thermo-mechanical properties

MACCHI, C.; ARANGUREN, M. I.; ANBINDER, P.S.; MOSIEWICKI, M.A.; MEIORIN, C.; SOMOZA, A.

Orlando

Conferencia; 18th International Conference on Positron Annihilation; 2018

Bowling Green State University

The present work is part of a systematic study of structural properties of tung oil (TO)-based thermoset polymers prepared by cationic polymerization. Recently, we have reported results on the effect of the composition and chemical aging of tung oil-styrene co-polymers on the free volume and dynamic-mechanical properties [1]. This work is addressed to study the effect of the co-monomer type on the structural properties of TO-based polymers. To this aim, the experimental results were obtained by means of positron annihilation lifetime spectroscopy (PALS), differential scanning calorimetry (DSC) and dynamic-mechanical test (DMA). Specifically, natural and synthetic co-monomers such as styrene (St), divinyl benzene (DVB), tung oil methyl esther (ME) and acrylated epoxidized soybean oil (AESO) were used to prepare the different TO/co-monomer samples with a fixed composition; i.e. weight ratio equal to 70/30. For each sample, values of the free nanohole volume (vh), the glass transition temperature (Tg), the storage and loss moduli (E´ and E´´, respectively) and tan delta (tan ) were obtained. On the other hand, we have followed up to one year the kinetic evolution of the free volume for each co-polymers and for two different aging conditions; room temperature and 50 °C.The obtained results were discussed in terms of the structure of the formed network, in particular to the packing of the molecular segments and the presence of dangling chains derived from the different monomers. For the kinetic evolution of vh, the results were interpreted in relation to the oxidative polymerization and degradative processes during the aging.