A. De Munno

Reaction of pig plasma benzylamine oxidase with betaaminopropionitrile

Beta-aminopropionitrile (BAPN) is an inhibitor of pig plasma benzylamine oxidase. BAPN is oxidized by benzylamine oxidase. Inhibition develops in a time-dependent fashion upon incubation of BAPN with the enzyme in the absence of substrate. The product of oxidation of BAPN by benzylamine oxidase, cyanacetaldehyde, was identified and prepared by synthesis. It is an irreversible inhibitor of the enzyme.

3,4-(Methylenedioxy)benzyl acrylate/acrylic acid copolymers as selective pH-controlled flocculants for finely divided titanium minerals

Abstract Fully synthetic tailor-made radical copolymers of 3,4-(methylenedioxy)benzyl acrylate with acrylic acid afforded excellent pH-controlled selective flocculation of aqueous ultrafine dispersions of the titanium minerals rutile and ilmenite. Sedimentation experiments proved that the copolymers, characterized by osmotic molecular weights in the range of 35 000–476 000 Da, produced stable, well separable flocs with rutile or ilmenite at acidic pH while they did not flocculate gangue minerals such as quartz. They showed the distinctive, very useful property of reversibly changing their effect from flocculation to dispersion or neutral by changing the pH. The formation of flocs is interpreted on the basis of a preliminary gathering process of the particles determined by the pH-dependent alteration of the particle surface solvation carried out with the copolymer.

Synthesis of vinyl monomers, polymers and copolymers containing aminoalkyl residues designed for interaction with enzymes

Abstract Hydrophilic polymers and copolymers containing aminoalkyl residues variously spaced from the polymer backbone, designed for the interaction with copper-containing amine oxidases, were prepared both through the radical copolymerization of new vinyl monomers having primary amino groups in the free or protected form and by chemical reaction of α, m-diaminoalkanes with the appropriate polymeric acyl precursor.

Synthesis of functionalized benzenesulphonyl monomers, polymers and copolymers designed for the selective flocculation of aqueous smithsonite dispersions

Abstract Four new vinylbenzenesulphonyl monomers containing glycine or quinoline residues have been synthesized and radically copolymerized with comonomers containing sterically hindered amino groups in order to obtain materials useful for the selective interaction with ultrafine aqueous smithsonite dispersions.

Synthesis of tailor-made copolymers containing 1,4-benzodioxane systems for pH controlled selective flocculation of mineral dispersions

Abstract Tailor-made selective flocculants for titanium minerals have been prepared, on the basis of a theoretical model of the morphology of a polymeric flocculant, through the synthesis of three new vinyl monomers containing the 1,4-benzodioxane system and their radical copolymerization with acrylic or methacrylic acid.

SYNTHETIC COPOLYMERS CONTAINING FREE OR PROTECTED CATECHOL RESIDUES FOR THE pH-CONTROLLED SELECTIVE FLOCCULATION OF ULTRAFINE DISPERSIONS OF ILMENITE WITH RESPECT TO RUTILE

ABSTRACT Several multifunctional polymers for the pH controlled flocculation of titanium minerals active towards ilmenite and selective respect to rutile have been prepared. They are radical vinyl copolymers containing catechol functions either free or protected and acrylic acid units. They show the distinctive property of changing their effect from flocculating to dispersing or inert and vice versa by changing pH, with great advantages for the best fulfilment of the flocculating process. The tendency of the ilmenite particles to gather, as a result of the combined effect of the cathecholic and carboxylic functions at acidic pH, is considered an essential conditions and a preliminary process for the formation of floes

Synthetic Copolymers Tailor-Made for the pH Controlled Selective Flocculation of Extrafine Dispersions of Ilmenite with Respect to Rutile

Following a new Methodical approach to fully synthetic tailor-made polymeric flocculants for a given mineral dispersion, we prepared several multifunctional poolymers for the pH controlled selective respect to rutile. They had the structure of radical vinyl copolymers containing 1,2-catecholic functions either free or protected and acrylic acid units. They also had the distinctive property of changing their effect from fuocculating to dispersing or best fulfilment of the flocculation process. The tendency of the ilmenite particles to gather, as a result of the combined effect of the catec holic and carboxylic functions at acidic pH, is considered and essential condition and a preliminary process for the formation of flocs.

Synthesis of tailor-made copolymers containing free or protected catechol residues for selective flocculation of mineral dispersions

Abstract pH-Controlled selective polymeric flocculants for titanium mineral dispersions have been designed and prepared through the synthesis of five new vinyl monomers containing catechol residues in free or protected form and through their radical copolymerization with acrylic or methacrylic acid. The synthesis of copolymers with unprotected catechol groups has been studied either by directly copolymerizing unprotected monomers in the presence of tri-n-butylborane or by chemically transforming copolymers obtained from protected monomers.

Polymeric β-adrenergic antagonist derivatives: Vinyl copolymers containing 3,4-dichloroisoproterenol residues

Abstract The new monomers (±)-1-(3′,4′dichlorophenyl)-N-(2′-propenyl)-2-aminoethanol and (±)-1-(3′,4′-dichlorophenyl)-N- ethenyloxyethyl-2-aminoethanol, with molecular structure correlated to that of dichloroisoproterenol, have been synthesized and copolymerized with acrylamide to afford polymers with covalently bonded functions stable in the biological fluids and active as β-adrenergic antagonists.