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A range of cross-linkable latex copolymers with biobased content of up to 90% was synthesized from isobornyl methacrylate combined with acrylic monomers based on high-oleic soybean oil (HO-SBM) or camelina oil (CMM) through miniemulsion polymerization. By varying the HO-SBM and CMM macromolecular fractions, the cross-linking density of the resulting materials can be altered due to differences in the fatty acid profiles of the plant-oil-based monomers. The glass transition temperature of the synthesized copolymers correlates very well with the calculated Flory–Fox values. A higher cross-linking density of the biobased copolymer films leads to a notable growth in the modulus of the materials, while the elongation at break decreases due to more restricted macromolecular mobility. Remarkably, the copolymer with the highest unsaturation degree in the investigated range (based on CMM) shows an increase in both the modulus and elongation at break, due perhaps to extended entanglements of fatty-acid-based side chains. The adhesion performance of the cross-linked biobased copolymers was evaluated by performing shear and peel strength measurements on steel and polypropylene. Based on the obtained results, the unsaturation degree of CMM and HO-SBM (determined by plant oil composition) can be applied as a criterion for adjusting adhesion by choosing plant-oil-based monomers (or their mixtures) with different unsaturation degrees to achieve properties and performance required for specific applications. 

To investigate the utility of acrylic monomers from various plant oils in adhesives manufacturing, 25–45 wt. % of high oleic soybean oil-based monomer (HOSBM) was copolymerized in a miniemulsion with commercially applied butyl acrylate (BA), methyl methacrylate (MMA), or styrene (St). The compositions of the resulting ternary latex copolymers were varied in terms of both “soft” (HOSBM, BA) and “rigid” (MMA or St) macromolecular fragments, while total monomer conversion and molecular weight of copolymers were determined after synthesis. For most latexes, results indicated the presence of lower and higher molecular weight fractions, which is beneficial for the material adhesive performance. To correlate surface properties and adhesive performance of HOSBM-based copolymer latexes, contact angle hysteresis (using water as a contact liquid) for each latex-substrate pair was first determined. The data showed that plant oil-based latexes exhibit a clear ability to spread and adhere once applied on the surface of materials differing by polarities, such as semicrystalline polyethylene terephthalate (PET), polypropylene (PP), bleached paperboard (uncoated), and tops coated with a clay mineral paperboard. The effectiveness of plant oil-based ternary latexes as adhesives was demonstrated on PET to PP and coated to uncoated paperboard substrates. As a result, the latexes with high biobased content developed in this study provide promising adhesive performance, causing substrate failure instead of cohesive/adhesive break in many experiments.