Comparative study of carboxylic acid adsorption on calcite: l-malic acid, d-malic acid and succinic acid

Recycled polyethylene/polycarbonate blends compatibilized with oxidized polyethylene/CaCO3

“…Therefore, it is anticipated that during the high shear thermal compounding process Ca‐mineral is fragmented into smaller particles, which is accelerated with the addition of OPE containing COOH group. The fragmented Ca‐mineral, OPE, and PC resin form a chemical network within the polymer composites through ionic and/hydrogen bonding interaction mechanism as demonstrated in Figure 8 17 . This interaction mechanism leads to good interfacial adhesion between LDPE and PC phases (Figure 6d–f), and consequently, the materials show high mechanical performance.…”

“…The fragmented Ca-mineral, OPE, and PC resin form a chemical network within the polymer composites through ionic and/hydrogen bonding interaction mechanism as demonstrated in Figure 8. 17 This interaction mechanism leads to good interfacial adhesion between LDPE and PC phases (Figure 6d-f), and consequently, the materials show high mechanical performance. Particularly, the compatibilization effect on the 50/50 blend of rLDPE/rPC was more profound when 5 wt% OPE was used during the melt-compounding process, which was reflected during measurements of tensile strength and stiffness of the corresponding composite material as discussed earlier (Table 2).…”

“…The application of polar additives such as carboxylic acid-containing molecules is likely to cleave the crystals, producing surfaces with terminal Ca 2+ ions. 17,18 Oxidized polyethylene (OPE) resins with several polar functionalities (e.g., C O, C═O, and CO 2 À ) are being used in different applications as a lubricant or viscosity modifier and dispersant for polymers, 19,20 degradation enhancing filler in polymer blends, 21 and photodegradation enhancer in PE-TiO 2 composite. 22 Several techniques such as corona or plasma treatment, flame, electrochemical, and chemicals (e.g., chromic acid, and acid permanganate) are used to oxidize PE to create polar functionalities on polymer surfaces.…”

“…Though these minerals have stable crystalline structures, they are sensitive to be fragmented into small particles during the high shear mechanical process. The application of polar additives such as carboxylic acid‐containing molecules is likely to cleave the crystals, producing surfaces with terminal Ca 2+ ions 17,18 …”

Solventless Amide Synthesis Catalyzed by Biogenic CaCO3 Materials

“…Experimental and theoretical studies have demonstrated that carboxylic acids coordinate on the surface of calcite and aragonite via their CO oxygen atom to either one surface calcium atom (or bridging two where the orientation of the surface calcium atoms allows), while O–H hydrogen atoms are coordinated to oxygen atoms of one of the carbonate groups of the surface. − These interactions (mainly electrostatic) are governed by the molecule adsorption mode, , crystal surface, and incorporation of cation species on surface . For instance, benzoic acid (BA) interaction in calcite and dolomite (Ca­(CO 3 ) 2 Mg) showed differences in the electronic charge density from the surface to BA.…”