Polymers and copolymers containing D‐galactose residues

Abstract

Polymers and copolymers based on the 6-methacrylate ester, the 6-acrylate ester, and the 6-0-ally1 ether of 1.2 : 3.4-di-O-isopropylidene-a-~-galactopyranose (diisopropylidenegalactose), and the 1-methacrylate ester of 2.3-O-isopropylideneglycerol, have been synthesised and characterised by chemical and infrared analysis. Methods have been developed for removing the protecting isopropylidene groups from the polymerised products to reveal the hydrophilic, hydroxylated carbohydrate residues.By comparing the properties (e.g. glass transition temperature, hydrolysis of isopropylidene residues, and crosslinking reactions) of galactose methacrylate and glycerol methacrylate polymers, it is possible to assess the influence of the heterocyclic ring and glycosidic hydroxyl group of the galactose moiety in synthetic polymer systems.A series of galactose methacrylate-methyl methacrylate random copolymers, containing different proportions of sugar residues, has been prepared, and it has been shown that the hydrophilic properties can be accurately controlled by the amount of galactose methacrylate in the copolymer. The industrial significance of this is discussed.Successful copolymerisations of diisopropylidenegalactose acrylate and methyl acrylate, diisopropylidenegalactose methacrylate and styrene, diisopropylidenegalactose acrylate and acrylonitrile, diisopropylidenegalactose methacrylate and vinyl acetate, and ally1 diisopropylidenegalactose and maleic anhydride are described, and in most cases the COpolymers have been readily deacetonated and characterised by phenylhydrazone formation.Evidence is presented to show that, in general, the introduction of reducing sugar units is a convenient method of increasing the reactivity and hydrophilicity of synthetic polymers and copolymers. ZUSAMMENFASSUNG:Polymere und Copolymere aus dem 6-Methacrylsaureester, dem 6-Acrylsaureester und dem 6-0-Allylather der 1.2 : 3.4-Di-O-isopropyliden-a-~-galaktopyranose (Diisopropylidengalaktose) sowie dem 1-Methacrylsaureester des 2.3-0-Isopropylidenglycerins wurden synthetisiert und durch chemische und IR-Analyse charakterisiert. Methoden mr Entfernung der Isopropyliden-Schutzgruppen aus den polymeren Produkten wurden entwickelt, u m die hydrophilen, hydroxylhaltigen Kohlenhydratreste freizusetzen.Durch Vergleich der Eigenschaften der Galaktosemethacrylat-und Glycerinmethacrylat-Polymeren (2. B. Glasumwandlungstemperatur, Hydrolyse der Isopropylidenreste, Vernetzungsreaktionen) ist es moglich, den EinfluR des heterocyclischen Ringes und der glykosidischen Hydroxylgruppe des Galaktoserestes in synthetischen Polymeren abzuschatzen. Polymers and Copolymers Containing D-Galactose ResiduesEine Reihe von statistischen Galaktosemethacrylat-Methylmethacrylat-Copolymeren mit verschiedenem Gehalt an Zuckerresten wurden hergestellt, deren hydrophile Eigenschaften durch den Gehalt an Galaktosemethacrylat genau kontrolliert werden konnen. Ihre industrielle Bedeutung wird diskutiert.Es werden erfolgreiche Copolymer isationen von Diisopropylidengalaktose-meth...

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