Evaluation of the emulsion copolymerization of vinyl pivalate and methacrylated methyl oleate

Abstract

In this study, we synthesized a new class of copolymeric lattices based on vinyl pivalate (VPi) and modified oleic acid (OA) through a batch emulsion polymerization process. The effects of the chemically modified OA [methacrylated methyl oleate (MAMO)] on the thermal stability, glass‐transition temperature (Tg), average molar masses [mass‐average molar mass (Mw) and number‐average molar mass (Mn)], and molar mass dispersity (Ð) of the copolymers were evaluated. The experimental results indicate that via the introduction of MAMO into the polymer chains resulted in significant reductions in Tg, Mw, Mn, and Ð; this demonstrated a decrease of Tg at approximately 40 °C when the MAMO molar fraction equaled 9% compared to the value observed for the pure poly(vinyl pivalate) (PVPi), which was equal to 80.5 °C. MAMO incorporation led to a significant decrease in the Mw value observed in the interval, with a differential from approximately 1.6 × 103 to 289.6 kg/mol, and Ð values between 2.17 to 1.55, which was when the MAMO molar fraction present in the VPi‐containing copolymers varied from zero (pure PVPi) to approximately 9 mol %. We also observed that the thermal stability of the copolymers decreased slightly when the MAMO concentration increased in the reaction medium. Despite this minor drawback, polymer lattices with a high colloidal stability were formed at a high rate of polymerization, and the elevated conversion was within the interval 90–100%. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44129.

Bio-based copolymers obtained through miniemulsion copolymerization of methyl esters of acrylated fatty acids and styrene

“…The second significant weight loss observed (420–520 °C) is resultant of polymeric chains with an elevated concentration of AFAME. It is worth mentioning that the thermal stability of poly(styrene‐ co ‐AFAME) in comparison to polystyrene has decreased with increasing of AFAME concentration in the reaction medium …”

Tailoring Acrylated Soybean Oil-Containing Terpolymers through Emulsion Polymerization

“…Figure 1 shows the 1 H-NMR spectrum of the mixture of fatty acids of soybean oil and the products of each modification step: epoxidation and acrylation. In the fatty acid spectrum (Figure 1a), a signal δ = 5.3 ppm is observed, characteristic of hydrogens attached to unsaturated carbons (H1 and H2, corresponding mainly to linolenic, linoleic and oleic acids), confirming the presence of double bonds in the chemical structure of the fatty acids [27]. After the epoxidation step, a reduction in the intensity of these signals is observed with the appearance of two signals at δ = 3.1 ppm and δ = 2.9 ppm, characteristic of hydrogens bonded to the carbon of the epoxide ring (H1 and H2).…”

“…When the methacrylic acid was replaced by the acrylated fatty acid mixture, a decrease in the glass transition temperature of the material with increasing fatty acid fraction was observed. In previous works, Jensen and collaborators observed that the incorporation of acrylated fatty acid into the polymer chain reduced the glass transition temperature of the copolymers [18,27]. Figure 4 shows the 1 H-NMR spectra of poly(methyl methacrylate-co-vinyl pivalate)-TAFA5_d and TAFA10_d polymer samples-evidencing the characteristic peaks of VPi (4.5-5.0 ppm), MMA (3.5 ppm), and AFA (2.3 ppm).…”

“…Jensen et al [27] presented an experimental study focusing on the synthesis of vinyl pivalate/methacrylated methyl oleate copolymer through emulsion polymerization. According to the results presented, an increase in the methacrylated methyl oleate concentration in the copolymer promoted the reduction in the copolymerization rate, which can be explained by the low solubility of the monomer in the aqueous phase.…”

Drug Micro-Carriers Based on Polymers and Their Sterilization

“…As a matter of fact, a very stable colloidal dispersion is generally obtained through ultrasonication or high shear devices that might be combined with a surfactant and a hydrophobic agent, which acts as a costabilizer in order to lead to the formation of droplets lying in the interval from 50 to 500 nm, exhibiting very narrow particle size distributions. Generally, highpressure homogenizers or sonicators are necessary when the formation of nanometric droplets requires a large amount of energy, which results from the application of high shear rates on the oil-in-water medium, leading efficiently to the breakage of the larger droplets to produce small droplets [217][218][219][220][221][222][223].…”