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Novel bio-based acrylate was designed through the epoxy ring-opening reaction of cardanol glycidyl ether (CGE) with fatty acids from camelina oil (FACO), followed by epoxidation of unsaturated chains and then acrylation of the epoxides. Cardanol- and camelina oil-based acrylates were also respectively synthesized for comparison purposes. The bio-based acrylate coatings were then produced under UV-radiation from the acrylates monomers with an addition of a photoinitiator. Polymerization of the acrylates and synthesis of the monomers were observed using Fourier transform infrared (FTIR) spectroscopy, and the chemical structures and acryl contents of the acrylates were confirmed by proton nuclear magnetic resonance (1H NMR). The mechanical and thermal properties of the cured acrylates were evaluated using tensile test, dynamic mechanical analysis (DMA), and thermogravimetric analysis (TGA). Observation of resistances to water, solvent, and hydrolytic degradation were conducted to water and toluene uptake test, methyl ethyl ketone (MEK) rub test, and a degradation test under sodium hydroxide solution. Gel content was measured to evaluate performance of the coatings, and other coating performances including gloss, adhesion, and pencil hardness were determined using the wood panel coated with the cured acrylates. Compared to acrylated epoxidized soybean oil (AESO) coating, the acrylate derived from the cardanol modified fatty acids showed higher tensile strength, hardness, glass transition temperature, thermal decomposition temperature at maximum degradation rate, and resistances to solvent and hydrolytic condition of the cured coating. Therefore, the newly designed acrylate is a great alternative to AESO.

Plant oils are attractive renewable feedstocks for biobased pressure-sensitive adhesives (PSAs). In this study, we investigated how the PSA adhesion properties were influenced by the compositions comprised of epoxidized soybean oil (ESO), 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate (ECHM), dihydroxyl soybean oil (DSO), rosin ester, and cationic photo initiator. When the amounts of ESO and photo-initiator were constant, the variables of ECHM, DSO, and rosin amounts and their interactions were significant in influencing PSA peel adhesion strength, with p values smaller than 0.05 under a 95% significance level. Rosin amounts with the largest coefficient of 0.94 compared to the other variables are the most determinant factors. The peel adhesion strength was higher when using relatively a lower level of ECHM and a higher level of ESO and rosin. A model with the coefficient of determination (R2) of 95.06% was obtained to describe the relationship between the amount of resin constituents (ECHM, DSO, and rosin) and PSA peel adhesion strength in the experimental variable ranges. The optimal PSA formulation without cohesive failure was (ECHM = 0.04, DSO = 0.7, rosin = 0.7), resulting in a peel adhesion strength of 4.45 N/in. Structure–property relationships of the PSAs were established via thermal and rheological studies.

The main challenge in converting polymerized epoxidized plant oils (P-EPO) to high performance materials is the limitation of their short cross-link structures and brittle properties. Herein, a network (N-2) fabricated from a renewable material, dihydrocoumarin (DHC), demonstrated the potential to overcome substantially the brittleness of P-EPO material. The fused ring in DHC was successfully opened via a solvent-free chromium(III) salen-mediated pathway, and a novel network, termed N-2, was created through an alternating copolymerization of DHC and diglycidyl ether epoxides. Repeating ether units in N-2 offered the capacity to sustain large deformation, and phenoxide end groups provided the reactivity to attack epoxides. Once a double network was built between N-2 and EPO derived network (N-1), a substantial performance improvement of P-EPO could be achieved. We targeted epoxidized soybean oil (ESO) as the model material, which showed a significant toughness enhancement (9-fold improvement in elongation ...

Several oleo-based pressure-sensitive adhesives (PSA) were studied as substitutes for current petroleum-based PSAs; however, PSAs derived from plant oils present challenges, such as relatively low biobased contents (20–90%) and complex processes (i.e., purifying, emulsifying, and drying steps). This paper demonstrates the possibility of transparent PSAs from neat acrylated epoxidized soybean oil (AESO) via fast and simple UV free-radical polymerization with 97–100% biobased contents. In this study, we controlled the degree of free radical polymerization by modulating the amount of UV irradiation to obtain a balanced cohesion and adhesion strength for PSA applications. This AESO PSA tape on a polyester film carrier had better peel and significantly higher shear strength on glass surfaces compared with a commercial reusable tape (Post-it®, 3M, St. Paul, MN, USA). The adhesion of the AESO PSA corresponded to its dynamic rheological properties. In addition, the adhesion/cohesion behavior of the PSAs was chara...

Functionalized plant oils such as epoxidized soybean oil (ESO) are widely used in plastic industries as additives and are available for more value-added applications. Pressure-sensitive adhesive (PSA) derived from petroleum feedstocks has a huge market ranging from tapes to packaging. Here we show a sustainable PSA derived from ESO/dihydroxyl soybean oil (DSO)/rosin ester (Sylvalite) via UV-initiated copolymerization. The ether crosslinks derived from cationic polymerization of ESO and copolymerization between ESO and DSO (or rosin ester) were demonstrated using 1H NMR, 2D 1H–1H COSY NMR, electrospray ionization mass spectrometry and thermal analyses (differential scanning calorimetry and thermogravimetric analysis). The PSA was formulated by modulating the ratio of ESO/DSO/rosin ester to achieve high performance. At a UV dose of 5.1–5.4 J cm−2 and 0.3–3% (w/w) of a photoinitiator, i.e. [4-(2-hydroxy-1-tetradecyloxy)-phenyl]phenyliodonium hexafluoroantimonate, the PSA at a ratio (by weight) of 1:1:0.7 (ESO/DSO/rosin ester) recorded the highest peel and loop tack strength, which was comparable to a commercial PSA, Scotch Magic Tape, and showed much stronger shear strength (>30 000 min) than the commercial tape (10 000 min). The high-shear rheological behavior and excellent thermal stability of the PSA were also demonstrated. © 2012 Society of Chemical Industry

Novel bio-based coating materials were developed through cationic ring-opening photopolymerization of dihydroxyl soybean oil (DSO) with commercial epoxy monomers [i.e., epoxidized soybean oil (ESO) and 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate (ECHM). The ether cross-linking and post-polymerization of the polymeric network were observed using Fourier transform infrared spectroscopy. Thermal properties of the bio-based coating materials and their copolymerization behaviors were examined using differential scanning calorimetry and a thermogravimetric analyzer. Cross-link density and molecular weight between cross-link were obtained from dynamic mechanical analysis. ECHM/DSO (1 : 1.43 weight ratio) films showed the highest elongation at break (49.2%) with a tensile strength of 13.7 MPa. After 2 months of storage, the elongation at break and tensile strength of films were 32% and 15.1 MPa, respectively. ESO/DSO films (w/w ratios of 1 : 0.1, 1 : 0.15, and 1 : 0.2) exhibited stable flexibility of 11–13% of elongation at break without significant reductions in tensile strength (2.5–4.4 MPa) during a 2-month shelf life. Optical transparencies of the films were comparable to commercial glass and polymers, and water uptake properties (0.72% and 2.83%) were significantly low. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41773.