Binding agents anhydrous

N -Heterocyclic Sulfanilamides. The parent sulfanilamide is manufactured by the reaction of A/-acetylsulfanilyl chloride with excess concentrated aqueous ammonia, and hydrolysis of the product. Most heterocycHc amines are less reactive, and the condensation with the sulfonyl chloride is usually done in anhydrous media in the presence of an acid-binding agent. Use of anhydrous conditions avoids hydrolytic destmction of the sulfonyl chloride. The solvent and acid-binding functions are commonly filled by pyridine, or by mixtures of pyridine and acetone. Tertiary amines, such as triethylamine, may be substituted for pyridine. The majority of A/ -heterocycHc sulfanilamides are made by simple condensation with A/-acetylsulfanilyl chloride and hydrolysis. 

Labhasetwar VD, Puranik PK, Dorle AK. Study of shellac-glycerol esters as anhydrous binding agents in tablet formulations. Indian J Pharm Set 1988 50 343-345. 

Polymer brushes can be grafted onto the pore wall of porous AAO membranes to improve the binding capacity, stability, and selectivity of the membranes. To initiate radical polymerization on the wall, surfaces need to be modified with an appropriate initiator or chain-transfer agent. Generally, a chlorosilane- or alkoxysilane-modifled initiator/chain-transfer agent is used however, the use of silanes requires anhydrous reaction conditions, which can be restrictive in some cases. Therefore, Klok and coworkers utilized catechol as an alternative anchoring moiety for surface-initiated polymerization [153]. The advantage of catechol-based initiators is that they can be immobilized in aqueous solutimi, without the need for... 

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