Search results
Results from the WOW.Com Content Network
The nature of soluble silicates is relevant to understanding biomineralization and the synthesis of aluminosilicates, such as the industrially important catalysts called zeolites. [7] Along with aluminate anions, soluble silicate anions also play a major role in the polymerization mechanism of geopolymers.
Synthetic polymers began replacing other chemical binders for soil stabilization in agriculture in the late 20th century. [1] Compared to traditional chemical binders, polymer soil additives can achieve the same amount of strengthening at much lower concentrations – for example, mixtures of 0.5-1% of various biopolymers have strength levels that match or exceed those of 10% cement mixtures ...
In the 1950s, Viktor Glukhovsky developed concrete materials originally known as "soil silicate concretes" and "soil cements", [5] but since the introduction of the geopolymer concept by Joseph Davidovits, the terminology and definitions of the word geopolymer have become more diverse and often conflicting.
Siliceous soils are formed from rocks that have silica (SiO 2) as a principal constituent.The parent material of siliceous soils may include quartz sands, chert, quartzite, quartz reefs, granite, rhyolite, ademellite, dellenite, quartz sandstone, quartz siltstone, siliceous tuff, among others. [1]
In polymer chemistry, polymerization (American English), or polymerisation (British English), is a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. [1] [2] [3] There are many forms of polymerization [4] and different systems exist to categorize them. IUPAC definition for ...
The subunits of colloidal silica particles are typically in the range of 1 to 5 nm. Whether or not these subunits are joined depends on the conditions of polymerization. Initial acidification of a water-glass (sodium silicate) solution yields Si(OH) 4. If the pH is reduced below 7 or if salt is added, then the units tend to fuse together in chains.
The carbonate that dissolved is therefore pulled out from the system while the silica precipitated recrystallizes into various silicate minerals, depending on the silica phase. [17] The solubility of silica strongly depends on the temperature and pH value of the environment [ 3 ] where pH9 is the controlling value. [ 1 ]
Ormosils (organically modified silicate) are obtained when silane is added to gel-derived silica during sol–gel process. The product is a molecular-scale composite with improved mechanical properties. Sono-Ormosils are characterized by a higher density than classic gels as well as an improved thermal stability. An explanation therefore might ...