Stereospecific radical polymerization of methacrylate bearing oxazolidone structure and improvement of glass transition temperature of urethane methacrylate copolymers

Abstract

We synthesized the novel methacrylate monomer bearing an oxazolidone structure (M1) and performed radical polymerization of M1 by traditional procedures. The glass transition temperature (Tg) of the obtained polymer (P1) was a significantly high value compared to that of poly(methyl methacrylate) and typical poly(urethane methacrylate)s. The copolymers of M1 and monofunctional urethane methacrylate derived from 2‐hydroxyethyl methacrylate and phenyl isocyanate (M2) exhibited a linear rise of the Tg values depending on the composition ratio of M1. The NMR analysis and the estimation of monomer reactivity ratio and Q–e values suggested that the improvement of glass transition temperature resulted from a stereoregularity, meaning a syndiotacticity of the copolymers improved with increasing the composition ratio of M1. Furthermore, the thermal curing reaction of M1 or M2 with bifunctional urethane acrylate successfully proceeded, then the Tg value of the cured product from M1 was much higher than that from M2.

Acid Gas Capture by Nitrogen Heterocycle Ring Expansion

“…Experimentally, many of these reactions involved catalysts such as water and hierarchical porous silica, metal organic frameworks, N-heterocyclic carbenes, or halide salts , or utilized supercritical CO 2 or ball milling . Not only do such reactions trap acid gases in covalently bound molecules, but they also produce derivatives of 2-oxazolidone and 1,3-oxazinan-2-one that are synthetically valuable for both medicinal − and polymer chemistry. − A range of synthetic approaches for substituted aziridines and azetidines are available. − Aziridines are extensively used commercially in textiles, adhesives, fuels, agriculture chemicals, ion exchange resins, surfactants, polymer monomers, and as alkylating agents for cancer therapy. , The use of aziridines and azetidines for novel polymerization processes has been demonstrated. , Notable aziridine containing natural products that have shown anticancer properties as DNA-alkylating and DNA cross-linking agents are the mitomycins . Specifically, mitomycin C is used clinically to treat breast, esophageal, and stomach cancers. , Azetidines are commonly used in medicinal chemistry, − natural products, − organic synthesis, , and organocatalysis. , Oxazolidinone based antibiotics, namely, linezolid and tedizolid, are relatively recent developments that are effective against methicillin-resistant Staphylococcus aureus (MRSA) .…”

“…As another example, the incorporation of oxazolidone in polymer networks has been shown to improve the mechanical toughness of self-mendable isocyanurate polymers . Incorporation of phenyl substituted oxazolidone moieties into methacrylate polymers increased the glass transition temperature of the material and increase heat resistance . These modified methacrylate monomers could be utilized in 3D printing applications and for dental implants. − In addition to reactions directly on isolated N-heterocycles, CO 2 insertion via ring expansion of aziridinofullerenes has been demonstrated to proceed with a tricyclohexylphosphine catalyst …”