Well-defined carbohydrate-based polymers in calcium carbonate crystallization: Influence of stereochemistry in the polymer side chain on polymorphism and morphology. (August 2015)

• Record Type: Journal Article
• Authors: Barz, Matthias; Götze, Sebastian; Loges, Niklas; Schüler, Timo; Theato, Patrick; Tremel, Wolfgang; Zentel, Rudolf
• Is Part Of: European polymer journal. Volume 69(2015:Aug.)
• Page Start: 628
• Page End: 635
• Publication Date: 2015-08
• Subjects: Crystallization of calcium carbonate -- Stereochemistry -- Carbohydrate-based polymers -- RAFT; Polymers -- Periodicals; Polymerization -- Periodicals; Polymères -- Périodiques; Polymérisation -- Périodiques; Polymerization; Polymers; Periodicals; Electronic journals; 547.705
• DOI: 10.1016/j.eurpolymj.2015.02.010
• Languages: English
• ISSNs: 0014-3057

Abstract

Graphical abstract: The effect of the polymers (poly(2-(2, 3, 4, 6-tetra-O-acetyl-β-d -glucosyloxy)ethylmetha-crylate) and poly(2-(2, 3, 4, 6-tetra-O-acetyl-β-d -galactosyloxy)ethylmethacrylate)) with molecular weights ( Mw ) of 10, 000–18, 000 g/mol and a PDI from 1.1 to 1.2 on the crystallization of calcium carbonate was studied. For the deprotected polymers differences in the phase selection of CaCO3 were observed. This effect is based on the chelating character of the OH-motif of the pyranoses. Highlights: Glucose and galactose based polymethacrylates are synthesized by RAFT polymerization. Acetyl-protected carbohydrate polymer conjugates do not influence CaCO3 crystallization. Stereochemistry of the carbohydrates controls crystal structure and morphology. Simulations indicate differences in polymer mobility on the crystal surface. Abstract: In this work we demonstrate the remarkable phase control on the crystallization of calcium carbonate by the stereochemistry of carbohydrate-based polymers. The polymers (poly(2-(2, 3, 4, 6-tetra-O-acetyl-β-d -glucosyloxy)ethyl methacrylate) and poly(2-(2, 3, 4, 6-tetra-O-acetyl-β-d -galactosyloxy)ethyl methacrylate)) have been synthesized from the respective glucose or galactose containing monomers (3 step synthesis) by RAFT polymerization leading to well-defined carbohydrate-based polymers with number averages of the molecular weights ( Mw ) of 10, 000–18, 000 g/mol and a dispersities (Đ) from 1.1 to 1.2. For the deprotected polymers we found differences in the phase selection of calcium carbonate. We found that this effect is based on the chelating character of the hydroxyl groups of the pyranoses and their individual orientation, as demonstrated by comparison of the protected and unprotected polymers in crystallization experiments as well as computer assisted simulations.