Geopolymerization involves the chemical reaction of alumino-silicate oxides (Al 3+ in IV-fold coordination) with alkali polysilicates yielding polymeric Si-O-Al bonds the amorphous to semi-crystalline three dimensional silico-aluminate structures are of the Poly(sialate) type (-SiO-Al-O-), the Poly(sialate-siloxo) type (-Si-O-Al-O-Si-O-), the Poly(sialate-disiloxo) type (-Si-O-Al-O-Si-O-Si-O-). Para nosso completo espanto, esta em seguida afirma que eles, chamados nephilins ou filhos das estrelas, engravidaram as filhas dos homens. A frase de Carl Sagan remete à Bíblia, segundo a qual houve gigantes sobre a Terra (Gn 6:4). These materials can polycondense just like organic polymers, at temperatures lower than 100‡. Se só nós existíssemos no universo, seria um tremendo desperdício de espaço.
High temperature techniques are no longer necessary to obtain materials which are ceramic-like in their structures and properties. New state-of-the-art materials designed with the help of geopolymerization reactions are opening up new applications and procedures and transforming ideas that have been taken for granted in inorganic chemistry. Spectacular technological progress has been made in the last few years through the development of new materials such as ‘geopolymers’, and new techniques, such as ’sol-gel’.
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