Organotin carboxylate polymers

Structure, Mechanism, and Reactivity of Organotin Carboxylate Polymers... 

Antifouling performance of these organotin carboxylate polymers indicates that their mode of action corresponds to the bulk abiotic bond cleavage model proposed by Castelli and Yeager (8). The controlling factors to be considered here are ... 

Antifouling performance of organotin carboxylate polymers show that their mode of action corresponds to the "bulk abiotic bond cleavage" model. All the controlling factors are analyzed. 

Reduction of HAS activity in applications in flame and weather resistant polymers and coatings containing halogenated FR is solved by means of HAS having reduced basicity (Sect. 3.3.2). The danger of antagonism in blends HAS/FR is reduced by addition of hydrotalcite [270]. terf-HAS 34 may be used for stabilization of PVC in combination with the conventional HS (salts of carboxylic acids, organotin compounds) [271]. 

Organotin Stabilizer n Any of an important class of stabilizers for PVC, notable for their high efficiency, compatibility, and imparting of clarity. The family includes sulfides and oxides of tin-alkyls or -aryls, organotins salts of carboxylic acids, organotins mercaptides, and trialkyl or triaryl tin alcoholates. Certain dioctyltin mercaptides and maleate compounds have been approved for food contact use. See also Di-n-Octyltin Maleate Polymer and Di-n-Octyltin-s,s bis(isooctyl mercaptoacetate). 

After some time, the partially-reacted outer layer of the polymer film, now containing hydrophilic free carboxylate groups, has little strength and is easily eroded by moving seawater (self-polishing effect), exposing a fresh layer of organotin acrylate polymer... 

The mode of action of the antifouling polymers thus conforms to the bulk abiotic bond cleavage model. All the controlling factors, viz., diffusion of water into the polymer matrix, hydrolysis of the tributyltin carboxylate, diffusion of tributyltin species from the matrix to the surface, phase transfer of the organotin species, and its migration across the boundary layer, are analyzed. It is found that the transport of the mobile tributyltin species in the matrix is the rate limiting factor. 

The first section, Chemical Reactions on Polymers, deals with aspects of chemical reactions occurring on polymers—aspects relating to polymer size, shape, and composition are described in detail. One of the timely fields of applications comprises the use of modified polymers as catalysts (such as the immobilization of centers for homogeneous catalysis). This topic is considered in detail in Chapters 2, 3, 8, 9, and 11 and dealt with to a lesser extent in other chapters. The use of models and neighboring group effect(s) is described in detail. The modification of polymers for chemical and physical change is also described in detail in Chapters 2 (polystyrene) 4 (polyvinyl chloride) 5 (polyacrylic acid, polyvinyl alcohol, polyethyleneimine, and polyacrylamide) 6 (polyimides) 7 (polyvinyl alcohol) 8 (polystyrene sulfonate and polyvinylphosphonate) 10 (polyacrylamide) and 12 (organotin carboxylates). 

Schreiber and co-workers (436) prepared a library calculated to contain 2.18 million polycyclic compounds through the 1,3-dipolar cycloaddition of a number of nitrones with alkenes supported on TentaGel S NH2 resin (Scheme 1.83). (—)-Shikimic acid was converted into the polymer bound epoxycyclohexenol carboxylic acid 376 (or its enantiomer), coupled to the resin via a photolabile linker developed by Geysen and co-workers (437) to allow release of the products from the resin in the presence of live cells by ultraviolet (UV)-irradiation. A range of iodoaromatic nitrones (377) was then reacted with the ot,p-unsaturation of the polymer-bound amide in the presence of an organotin catalyst, using the tandem esterification/ dipolar cycloaddition methodology developed by Tamura et al. (84,85) Simultaneous cyclization by PyBrop-mediated condensation of the acid with the alcohol... 

By appropriate choice of the reactants and the reaction conditions, a phenol-substituted carboxylic acid may react with an organotin compound to give both an organotin ester and an organotin aryl oxide within the same molecule. The reaction of trimethyltin chloride with 4-hydroxy-3-methoxybenzoic acid (HVAH) in the presence of water and pyridine at 130 °C in a sealed tube gave the unique two-dimensional coordination polymer 134 (equation 2)286. 

With di- or triisocyanates, insoluble polymers are obtained. Reaction (a) illustrates the use of amides in catalysis. In commercial practice, organotin alkoxides or carboxylates are preferred, being used for catalytic trimerization of isocyanates to cyanurates and addition of diols to diisocyanates to yield polyurethanes . ... 

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