Preparation and properties of glycerin ester of tung oil modified rosin

Abstract

Tung oil modified rosins (TR) were prepared by reaction rosin with different amount of tung oil via Diels-Alder addition reaction and further used in the formulation of glycerin ester of tung oil modified rosins (GTR) with flexible characteristics. The effects of the amount of tung oil on the bromine value, molecular weight, thermostability, physical, and tackifying properties of GTRs were studied. The results showed that the bromine value of GTRs decreased and molecular weight of GTRs increased with the increase in the amount of tung oil. Meanwhile, increasing the amount of tung oil resulted in a significant decrease in both the softening points and viscosities of GTRs, but a slight increase in the thermostability of GTRs due to the incorporation of the flexible fatty chains into the rigid hydrophenanthrene units in rosins. Applied in PU adhesive as tackifier, the increase of the flexible chains content in GTRs led to an increase first and then decrease in both the miscibility of GTRs with PU and the T-peel strength of adhesives. The elongation at break of films increased monotonously, but their tensile strengths increased first and then decreased with increasing the flexible chains content in GTRs. GTRs with desired properties were prepared when the tung oil/rosin weight ratios were in the range from10/100 to 40/100.

Advances in Rosin-Based Chemicals: The Latest Recipes, Applications and Future Trends

“…Rosin-tung oil Diels-Alder adduct is a yellowish solid. It can be prepared from levopimaric acid and tung oil according to Scheme 82, prior to precipitation and drying [265,266]. Its application is a filler, tackifier and adhesion promoter in polyurethane [265] and UV-curable adhesives [266].…”

A novel acid catalyst based on super/subcritical CO2-enriched water for the efficient esterification of rosin

“…In addition, rosin contains lesser amounts of nonacidic compounds [ 2 ]. Resin acids have cyclic structures, with both conjugated and nonconjugated carbon–carbon double bonds and carboxy groups [ 3 ]. As a result, several different methods can be used to chemically modify rosin.…”

“…Resin acids have a tricyclic phenanthrene structure that results in high steric hindrance, such that there is a high activation energy for esterification reactions. For this reason, the esterification of rosin has to be carried out at elevated temperatures and using a highly active catalyst [ 3 ]. Initially, alkaline catalysts such as CaO, Ca(OH) 2 and LiOH were used for the esterification of rosin, although these have been largely abandoned because they affect the colour of the rosin ester [ 5 ].…”

Synthesis and characteristics of tung oil-based acrylated-alkyd resin modified by isobornyl acrylate

“…6 Compared to other unconjugated drying oils, such as soybean and linseed oils, tung oil has a faster drying time, better water resistance, and greater hardness. [7][8][9][10] Tung oil has a highly unsaturated and conjugated triene structure, and hence it can easily be chemically modied in the preparation of alkyd resin, UV-curable acrylate resin, epoxy resin and related polymers to obtain better performance.…”