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As a type of biodegrada polyvinyl alcohol (PVA) film, its environmentally friendly characteristic has been widely recognized around the world. However, its poor water resistance largely limits the popularization and application, due to a large number of hydrophilic groups in PVA molecules. In this work, glutaraldehyde and urea were used to react with PVA by acetal reaction, and then the plasticizers (glycerol, PEG-400, MgCl2) were added to the system to destroy the hydrogen bonding of PVA and reduce its crystallinity, in order to achieve the plastic modification effect. Finally, the structure of the products and the performance of the cured films were characterized by Fourier transform infrared spectrometer (FT-IR), thermogravimetric (TG) analysis, physical and mechanical properties, and contact angle. The results showed that the water resistance and thermal stability of PVA films could be enhanced by the crosslinking reaction of PVA with glutaraldehyde and urea. The addition of glycerol, PEG-400 and MgCl2 could improve the elongation at break and tensile strength of PVA films. And when the additive amount of glutaraldehyde, urea, glycerol, PEG-400 and MgCl2 in the formula were 4%, 0.5%, 6% and 2%, respectively, the mechanical properties of the film were optimal with the elongation at break of 136.7% and the tensile strength of 3.48 MPa. [ABSTRACT FROM AUTHOR]

In this paper, methyl eleostearate was prepared via the transesterification reaction betweent ung oil and methanol, and then was used to synthesize methyl eleostearate-maleic anh ydride CME-MA) adduct by D-A reaction under UV light. The structure of ME-MA was also identified and characterized by FTIR spectra, UVvis spectra and 1H NMR. Finally, ME-MA adduct was applied to the polyurethane coatings to study the effect of photoinitiator, reactive diluent and ME-MA adduct on the cured films. The experimental results concluded that the optimum formula conditions were as follows: the photoinitiator was TPO, the reactive diluent was HDDA, the amount of TPO was 5% and the addition amount of ME-MA was 20%. The cured film formation possessed good performance, including the highest gel fraction of 96.5%, tensile strength of 11.3 MPa and elongation at break of 23.2%. [ABSTRACT FROM AUTHOR]

Tung oil, as an important strategic biomaterial and renewable biomass resource, has attracted increasing attention due to its high value of research and application. In this study, eleostearic acid glyceride (the main component of tung oil) was transformed to methyl eleostearate (ME) by transesterification, and then reacted with catechol (CAT) via Friedel-Crafts alkylation using SO3 H-functionalized ionic liquid as catalyst. The alkylation products (CAT-ME) similar to urushiol (urushiol analogues) were successfully synthesized, and confirmed by the characterization results of infrared spectroscopy, UV visible spectroscopy, NMR spectra and IIPLC-MS spectra. [ABSTRACT FROM AUTHOR]