Organotin stability

Alkyltin Intermedia.tes, For the most part, organotin stabilizers are produced commercially from the respective alkyl tin chloride intermediates. There are several processes used to manufacture these intermediates. The desired ratio of monoalkyl tin trichloride to dialkyltin dichloride is generally achieved by a redistribution reaction involving a second-step reaction with stannic chloride (tin(IV) chloride). By far, the most easily synthesized alkyltin chloride intermediates are the methyltin chlorides because methyl chloride reacts directiy with tin metal in the presence of a catalyst to form dimethyl tin dichloride cleanly in high yields (21). Coaddition of stannic chloride to the reactor leads directiy to almost any desired mixture of mono- and dimethyl tin chloride intermediates ... 

Polyvinyl chloride/Polyvinyl acetate Good prevent yellowing. High-molecular-weight organotin stabilizers improve radiation stability color-corrected radiation formulations are available. Less resistant than PVC. 

Over 90% of organotin stabilizers are used in rigid PVC. Table 3 provides details of the estimated quantities of methyl-, butyl-, and octyltin stabilizers used in rigid and flexible PVC applications, whereas Table 4 details the types of applications in which the PVC products are used. 

Table 3 Use of organotin stabilizer types in rigid and flexible PVC in Europe (2001). ...

PVC is the only plastic in which organotin stabilizers are used. The total European market for PVC is... 

Mesch KA, Kugele TG (1992) Use of organotin stabilizers — Risk assessment analysis. Journal of Vinyl Technology, 14 131-134. 

Quevauviller Ph, Donard OFX (1991) Organotin stability during storage of marine waters and sediments. Fresenius J Anal Chem 339 6-14. 

ASSESSING THE WORKPLACE ENVIRONMENTAL PERFORMANCE OF ORGANOTIN STABILIZERS USED AT PVC PROCESSING FACILITIES... 

WATER RjSnX RjSnXj, RSnXj Antifouling coatings, molluscicides, overspray from agricultural operations, land runoff from agricultural use, industrial processes (i.e., slimicides in paper manufacture) Leaching from organotin stabilized polyvinyl chloride... 

To improve the thermal stability of PVC, it is common to add stabilizers, generally metalloorganic compounds, in concentrations of 1-5 parts per 100 parts of PVC. Although the cis-1,4-polybutadiene grafted PVC, in the absence of an added stabilizer, yielded essentially colorless or only faintly discolored films, completely colorless films were obtained when the conventional stabilizers were added in concentrations of 0.1-0.3 parts per 100 parts of modified PVC. Organotin stabilizers were not necessary and, in some cases, actually resulted in greater color development than when they were absent. 

Polyvinyl chloride Organotin stabilizers Heptane glacial Acetic acid 1 1... 

II elements invariably are not used singly, but in Subgroup A-B couples. Aside from lead compounds, the elements currently used in most applications are barium, cadmium, calcium, zinc, and tin—e.g., the calcium-zinc soap systems for nontoxic (food contact) applications, the general purpose barium-cadmium soap stabilizers, and the organotin stabilizers. The objective of this paper is to consider the rheological consequences of... 

Concentration levels of heat stabilizers in various PVC products are in the range 1.5-3.0% for metal soaps and 0.3-2.5 % for organotin stabilizers (Pospfsil, 1990c). Aliphatic (22) or mixed aliphatic/aromatic phosphites (23, 24) are used together with polyols (e.g., pentaerythritol or sorbitol) and acid scavengers as co-stabilizers in PVC (Pospfsil, 1990c). 

Heat stabilizers have preventive and curative functions (Andreas, 1990). As preventive stabilizers, they deplete initiation sites in the PVC backbone by elimination or complexation of reactive chlorine atoms by organotin stabilizers (e.g. 45) according to... 

Organotin stabilizers containing sulfur (e.g. 45) or their transformation products 96, 97 are considered as hydroperoxide-decomposing antioxidants (Al-Malaika, 1989). Within this stabilizing function, thiol 97 is oxidized by hydroperoxide in disulfide 99 and sulfenic acid 100, having peroxidolytic properties. 

Schwope, A.D., Till, D.E., Ehntholt, D.J.. Sidman. K.R.. Whelan. R.H., Schwartz, P.S., Reid R.C., 1986, Migration of an organotin stabilizer from polyvinyl chloride film to food and food simulating liquids. DeutscheLebensmittel Rundschau 82 (9) 277-282. 

Rigid PVC is polymerized at 55-70°C and then compounded with organotin stabilizer, acrylic processing aid, lubricants, and optionally with rubbery impact modifier. 

Philadelphia, Pa., llth-12th Oct.2000, p.97-103 MECHANISM OF ORGANOTIN STABILIZATION OF POLY(VINYL CHLORIDE) 5. MECHANISM OF PVC STABILIZATION BY STANNIC COMPOUNDS Fisch M H Bacaloglu R Dooley T Diaconescu C Crompton Corp. 

The modes of action of the organotin stabilizers added to the extent of ca. 1-5% are considered to be complex, but include... 

Sn Asbestos, cellulose Sn-catechol-complex from catechol violet Foodstuff (organotin stabilizer) Photometry 80 ppm 119)... 

This section deals with the stabilization of PVC by organotin stabilizers having different alkyl groups (methyl, ethyl, n-butyl, n-octyl, etc.) and different ligands (carboxylates, mercaptides, etc.), the mechanism of reaction and the evaluation of stability by yellowness index and conductivity. 

There are three major types of tin stabilizers (organotin stabilizers), distinguished by their respective alkyl groups n-octyl, n-butyl, and methyl ... 

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