Polymers organotin compounds

In [222], polymer organotin compounds with sulfur bridges were proposed as stabilizers of suspension polyvinyl chloride. 

Organic derivatives of Group IV find applications in diverse areas. Especially important are the silicone polymers, organotin compounds as stabilizers for plastics and as biocides and organolead antiknock agents for petrol. 

Organotin compounds are important industrial chemicals. One major use is as stabilizers for poly(vinyl chloride) (PVC) plastics. These additives, one example of which is dioctyltinmaleate, inhibit degradation of the polymer by heat, light, and oxygen. In the absence of these tin compounds, PVC yellows and becomes brittle. 

Organotin compounds (biocides and polymer stabilisers) in water were analysed by means of HS-SPME-GC and GC-MS (SIM) [296],... 

Potentiometric titration procedures with sodium methoxide have been reported for non-sulfur-containing organotin compounds in solvent extracts of polymers, and for phenolic antioxidants with sodium isopropox-ide in pyridine medium [21]. Organotin compounds in solvent extracts of PVC can be determined by potentiometric and manual titration procedures [487,488]. 

In recent years considerable progress has been made in the synthesis of new organotin monomers and polymers and in their application in various branches of technology. The ever increasing interest in organotin compounds including organotin polymers may be attributed to their unique properties and the possibility to develop novel materials with specified characteristics. 

Recent survey articles 61,62) are mainly concerned with the synthesis, properties and applications of carbon-chain organotin polymers and with the use of organotin compounds in polymer chemistry as stabilizers, fungicides, etc. It should particularly be noted that polymers on the basis of trialkylstannyl methacrylates exhibit biocide properties. 

In recent reviews 85,86> are discussed the uses of organotin compounds as stabilizers and catalysts in polymer chemistry. 

Low-molecular weight organotin compounds are known to easily undergo chemical conversions upon UV-irradiation1). However, the photochemistry of organotin polymers is still obscure. 

Conventional Systems. In the conventional antifouling compositions, the organotin compound (TBTO, TBTF, TBTC1, TBTOAc) is mechanically mixed into the paint vehicle. When the TBT species is completely soluble in the polymer matrix, factors (a) and (b) become unimportant in most cases. The mobile species is already present its diffusion in the matrix, phase transfer and migration across the boundary layer into the ocean environment may be represented by Figure 2a. When the organotin compound forms a dispersed second phase, rate of its dissolution in the polymer matrix becomes another factor to consider. 

The emphasis on organotin-containing polymers is the results of several factors. The first one involves the early discovery of their biological activity and more recently that these organotin compounds generally degrade to nontoxic inorganic compounds so that they are environmentally friendly. The second reason is the commercial availability of a wide... 

ORGANOTIN COMPOUNDS. A family of alky l tin compounds widely used as stabilizers for plastics, especially rigid vinyl polymers used as piping, construction aids, and cellular structures. Some have catalytic properties. They include bntyl tim trichloride, clibntyltin oxide, etc., and various methyldn compounds. They are both liquids and solids. 

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