Mechanochemical Production of Urea-citric Acid Copolymer

Abstract

Increasing non-biodegradable plastic consumption is a great factor that contributes to worldwide pollution and global warming. Mechanochemistry provides a clean, solvent-less, route for chemical reactions such as polymerization based on the absorption of mechanical energy. Urea polymers have several applications in industrial and medical area, such as paints, resins, plastic, wood glue, separating aliphatic hydrocarbons, coating, and pharmaceutical drugs. In this study, a copolymer of urea and citric acid was synthesized using a planetary ball mill as grinder with fixed reaction time and rotational speed, varying the number and material of the planetary ball mill sphere to find the effects of those two conditions in the yield percentage of the copolymer. The purified polymer was characterized by Infrared spectroscopy (FTIR) and Nuclear Magnetic Resonance – NMR. Results confirmed that polymeric material is formed by the reaction between citric acid and urea without any catalyzer using mechanochemistry. NMR results showed that the reaction occurred between urea and the acid groups at the ends of the chain, while the central COOH remained intact.

Engineering Nitrogen‐Doped Carbon Quantum Dots: Tailoring Optical and Chemical Properties through Selection of Nitrogen Precursors

“…Under hydrothermal condition, CA can form five‐ and six‐membered anhydride structures that readily react with amines or alcohols to generate esters, polyesters, amides, and polyamides. [ 24 ] Although CA itself isn't fluorescent, it can react with certain amines to produce an array of highly fluorescent compounds. [ 25 ] However, the synthesis of CQDs from CA is highly sensitive to the synthesis conditions, such as decomposition temperature, residence time, and the type of nitrogen source used.…”

Chemically induced crosslinked enhanced emission of carbon polymer dots discerning healthy and cancer cells through pH-dependent tunable photoluminescence

“…These data support the structure of the polymer unit proposed herein, as also demonstrated elsewhere with the same substrates. 18,19,26…”

“…These data support the structure of the polymer unit proposed herein, as also demonstrated elsewhere with the same substrates. 18,19,26 The UV-vis absorption spectrum of the CPDs exhibits a peak at 330 nm with a broad absorption band extending to 500 nm (Fig. S6A, ESI †).…”

Synthesis and Characterization of a New Nanocatalyst Based on Keggin-Type Polyoxovanadate/Nickel-Zinc Oxide, PV14/NiZn2O4, as a Potential Material for Deep Oxidative Desulfurization of Fuels

“…In order to prepare NiZn 2 O 4 nanoparticles, the following method was carried out: − Ni­(NO 3 ) 2 ·6H 2 O (0.29 g) was dissolved in 15 mL of DW, and the obtained solution was added dropwise to the solution of Zn­(NO 3 ) 2 ·6H 2 O (0.10 g in 15 mL of DW) with the molar ratio of 1:2 under magnetic stirring (as a solution of A). Furthermore, citric acid solution (0.42 g in 15 mL of DW) and CH 4 N 2 O (0.24 g in 15 mL of DW) were blended with the molar ratio of 1:2 under sonication and the obtained mixture was heated to 75 °C (as a solution of B).…”