The precise synthesis of polymers derived from alkyl lactate ester acrylates is reported for the first time.Kinetic experiments were conducted to demonstrate that Cu(0) wire-catalyzed single electron transferliving radical polymerization (SET-LRP) in alcohols at 25 ºC provides a green methodology for the LRP of this forgotten class of bio-based monomers. The acrylic derivative of ethyl lactate (EL) solvent and homologous structures with methyl and n-butyl ester were polymerized with excellent control over molecular weight, molecular weight distribution, and chain end functionality. Kinetics plots in conventional alcohols such as ethanol and methanol were first order in monomer with molecular weight increasing linearly with conversion. However, aqueous EL mixtures were found to be more suitable than pure EL to mediate the SET-LRP process. The near quantitative monomer conversion and high bromine chain-end functionality, demonstrated by MALDI-TOF analysis, further allowed the preparation of innovative bio-based block copolymers containing rubbery poly(ELA) sequences. For instance, poly(ELA-b-poly(glycerol acrylate) block copolymer self-assembled in water to form stable micelles with chiral lactic acid-derived block forming micellar core as confirmed by pyrene-probe-based fluorescence technique. Dynamic light scattering (DLS) and transmission electron microscopy (TEM) measurements revealed nanosize spherical morphology for these bio-based aggregates.

We report a new strategy toward the development of block copolymer surfactants from chemicals of the lactic acid family. A particularly unique aspect of this work is the use of green solvents as biobased platform chemicals to generate well-defined and nanostructure-forming materials. Herein, efficient functionalization of ethyl lactate (EL) and N,N-dimethyl lactamide (DML) solvents with acrylate groups generated monomers that could be polymerized by the photoinduced copper-catalyzed living radical polymerization process to yield polymeric materials with different water solubilities. These lactic acid-derived monomers were used as a major component in well-defined diblock copolymers composed of poly­(EL acrylate) and poly­(DML acrylate) segments as hydrophobic and hydrophilic building blocks, respectively. The resulting amphiphilic copolymers could self-assemble in aqueous solution to form nanoparticles with different morphologies (e.g., large-compound micelles and vesicles). Subsequently, the formed amphiphilic polymers were employed as efficient stabilizers in the emulsion polymerization of methyl methacrylate and styrene, offering a facile method for the synthesis of well-defined and stable polymer latexes in the range of 100–200 nm, demonstrating the practical significance of these biobased polymers in nanomaterial synthesis.

To be fully recyclable, covalent adaptable networks must ultimately be able to overcome all topological restrictions and flow. By using a statistically based method, it was shown that the extent of stress relaxation in disulfide-containing thiol−ene polymers is closely correlated to the fraction of permanent cross-links. Given sufficient disulfide content, the cured materials can be recycled at moderate temperatures with no apparent loss in tensile properties. Since the materials also feature ester bonds, even when the disulfide content is low, one can increase the reprocessing temperature to trigger transesterification reactions which ensure full stress relaxation and recyclability.

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New poly(acylhydrazone) vitrimeric-type materials derived from vanillin have been studied.

A series of bio-based polyimine vitrimers was obtained and characterized. A diimine-diglycidyl monomer (DIDG) was synthesized by condensing vanillin with 4,4′-oxydianiline (ODA) and further glycidylation with epichlorohydrin. This compound was cross-linked with three different Jeffamines (Jeff230, JeffD400, and JeffT403) with a different number of poly(propylene glycol) units in their structure and different functionalities. Trimethylolpropane triglycidyl ether (TMPTE) was added to the formulation to improve the thermal, mechanical, and thermomechanical properties. All of the materials prepared showed T g’s above 66 °C, good vitrimeric behavior being the maximum relaxation rate reached by the material prepared from JeffD400, which also allows the most extensive degradation when treated with an acidic aqueous solution. These polyimine vitrimers can entirely relax the stress in less than 10.5 min at 150 °C without any added catalyst. All of the materials prepared could be satisfactorily recycled up to 200 °C also presenting an excellent self-welding ability.

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