Synthetic Polymers and Fire Retardants

World plastics consumption exceeded 50 x 10 tons in 1995 and at the end of the twentieth century it was growing at a rate of over 5% pa. There r ains a constant demand for higher-performance plastics 

Some P-containing monomers can be self-condensed to form homo-polymers, while others can be co-polymerised with a non-phosphorus-containing monomer. Desirable commercial properties are sought in polymers of the latter type, which employ a minimal amonnt of the usually more expensive phosphorus compound. 

The major application of organophosphorus polymers has so far been in flameproofing and fire retardancy, but they have also found an important role in the modification of the properties of established non-phosphorus polymeric materials. In addition, growing applications lie in the areas of ion exchange materials, snrface adhesives, catalysts and tooth preservation agents. 

Polymerised phosphonates constitute the most studied group of organophosphorus polymers, although in some cases the P-C linkages may be confined to the side chains. Among the methods which have been nsed for homopolymer formation are the heating of vinyl or allyl phosphonates 

Arbusov-type rearrangements may be effected with some phosphite monomers (12.159,12.160), or with preformed polymeric phosphites (12.161), to produce polymeric phosphonates. 

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