Free Radical Polymerization Behavior of the Vinyl Monomers from Plant Oil Triglycerides

Abstract

A one-step method of plant oil direct transesterification was used to synthesize new vinyl monomers from sunflower (SFM), linseed (LSM), soybean (SBM), and olive (OVM) oils. The degree of unsaturation in plant oil fatty acids was used as a criterion to compare the free radical polymerization behavior of new monomers. The number-average molecular weight of plant oil-based homopolymers synthesized in toluene in the presence of AIBN at 75 °C varies at 11 000–25 000 and decreases as follows: poly­(OVM) > poly­(SFM) > poly­(SBM) > poly­(LSM), corresponding to increasing degree of unsaturation in the monomers. Rate of polymerization depends noticeably on the degree of unsaturation in monomers. Due to the allylic termination, chain propagation coexists with effective chain transfer during polymerization. The obtained values of C M (ratio of chain transfer and propagation rate constants) depends on monomer structure as follows: C M(LSM) > C M(SBM) > C M(SFM) > C M(OVM). 1H NMR spectroscopy shows that the fraction of the reacting allylic atoms does not vary significantly for the synthesized monomers (7–12%) and is determined entirely by plant oil degree of unsaturation. The glass transition temperature of homopolymers [T g = 4.2 °C for poly­(SFM), T g = −6 °C for poly­(SBM)] from new monomers indicates that varying biobased fragments in copolymers might considerably change the intermolecular interactions of macromolecules and their physicochemical properties.

Plasticizing and Hydrophobizing Effect of Plant OilBased Acrylic Monomers in Latex Copolymers with Styrene and Methyl Methacrylate

“…Recently, we developed a one-step method of plant oil direct transesterification into vinyl monomers for free radical polymerization and copolymerization [11][12][13]22]. It was demonstrated that the rate of POBM homopolymerization, where chain propagation coexists with chain transfer reaction on monomers, is determined primarily by the amount of unsaturation in each plant oil triglycerides.…”

“…It was demonstrated that the rate of POBM homopolymerization, where chain propagation coexists with chain transfer reaction on monomers, is determined primarily by the amount of unsaturation in each plant oil triglycerides. In the next step, stable latexes containing up to 50wt% of plant oil-based content were synthesized using miniemulsion copolymerization of POBM with their petroleum-based counterparts [13].…”

“…It was demonstrated in our previous work that CM (ratio of chain transfer and propagation rate constants) depends on monomer unsaturation. This value is larger for more unsaturated SBM (CM,OVM = 0.15, CM,SBM = 0.26) [13]. It has also been demonstrated that monomer unsaturation amount (UMF) impacts resulting copolymer molecular weight and can be used as a parameter for comparing physico-chemical and thermomechanical properties of latex films.…”

“…When long unsaturated fatty acid fragments (C18) of POBMs are incorporated into the macromolecules, they can reduce the intermolecular interactions and increase intermolecular distance, thus increasing chain mobility and facilitating polymer softening (plasticizing). Suitability of POBMs in free radical copolymerization reaction with other vinyl monomers was demonstrated in our previous study [11][12][13].…”

“…The internal plasticization effect can be achieved by copolymerization of various commercial vinyl monomers with a library of POBMs developed in our group [11][12][13]. When long unsaturated fatty acid fragments (C18) of POBMs are incorporated into the macromolecules, they can reduce the intermolecular interactions and increase intermolecular distance, thus increasing chain mobility and facilitating polymer softening (plasticizing).…”