Physical polyphosphate

Other. A large variety of additives are used in paper-coatiag colors primarily to modify the physical properties of the colors (102). At high soHds concentrations in water, mineral pigment particles tend to associate and form viscous pastes. Dispersants (qv) are used to prevent this and to provide low viscosity slurries. Common dispersants include polyphosphates and sodium polyacrylate [9003-04-7]. Various water-soluble polymers are added to coatiag colors and act as water-retention agents and as rheology modifiers. 

The flame retardant mechanism for phosphorus compounds varies with the phosphorus compound, the polymer and the combustion conditions (5). For example, some phosphorus compounds decompose to phosphoric acids and polyphosphates. A viscous surface glass forms and shields the polymer from the flame. If the phosphoric acid reacts with the polymer, e.g., to form a phosphate ester with subsequent decomposition, a dense surface char may form. These coatings serve as a physical barrier to heat transfer from the flame to the polymer and to diffusion of gases in other words, fuel (the polymer) is isolated from heat and oxygen. 

Calcium polyphosphate, dissociation and chain length, 4 48 Calcyclin, 46 454-456 Californium, 20 111 availability and price, 31 2 isotopes, 2 201 melting point, 31 6 oxidation state, 2 197 physical properties, 31 36 preparation and purification, 31 5, 7, 12, 33 apparatus, 31 34, 35 purity, 31 3 radioactivity, 31 33 vapor pressure, 31 6 Califomium-252, a-decay, 31 28 Californium oxide, metallothermic reduction, 31 7, 33... 

Physical properties of solid polyphosphate glasses and their melts are also in accord with the conclusions drawn from chemical studies. The X-ray diffraction pattern shows the polyphosphate anions to consist of long chains of P04 tetrahedra (32) and the same conclusion is reached by studying the double refraction of fibers formed by rapidly drawing supercooled melts of Graham s salt (101). 

Pure deuterophosphoric acid is stable indefinitely as a solid but in the fused state always contains traces of pyro-and other polyphosphates which depress the freezing point of the compound. Its chemical properties are similar to those of phosphoric acid. The more important physical properties of the two compounds (supercooled) are compared in the following table.3... 

D. L. Correll and N. E. Tolbert (1964). Ribonucleic acid-polyphosphate from algae. B. Physical and chemical properties of the isolated complexes. Plant Cell Physiol., 5, 171-191. 

Oxidized starch reagents may be used in washing powders as substituents of polyphosphates [11]. As investigations show OSR possess the number of unique physical-chemical properties allowing hoping on their application as one of the main components of detergents. 

Of course, ionic interactions in a gelatin/polyphosphate or gelatin/-gum arabic coacervate may affect the physical properties of the solids isolated from both types of coacervates, but this remains to be defined. 

A chemical classification into orthophosphate, polyphosphate, and organic P is made as well as the physical separation of these three chemical forms into soluble and insoluble components by filtration through... 

Physical and chemical characteristics of a typical ammonium polyphosphate solution of 10-34-0 grade made by this process are given in Table 10.6. 

There is a continuous transition in the physical properties of solutions of polyphosphates on passing from lower- to higher-molecular-weight species. Apart from the first few members of the series, they all exhibit typical properties of polyelectrolytes. Colloidal behaviour is not exhibited by polyphosphates, however, until the average chain lengths are of the order of hundreds. 

The presence of ammonium polyphosphate and melamine cyanurate filler causes a slight worsening of the physical and mechanical properties of PU and PIR foams but the fire behaviour of flame retarded foams is better than that of unfilled foams. In particular the use of the previously mentioned mixture, which produces a synergistic effect causes a significant improvement of the fire performance. This is characterised by a remarkable decrease of RHR and weight loss without worsening smoke opacity and toxicity [183]. 

Polyphosphoesters are biomaterials composed of phosphorus-incorporated monomers. These polymers consist of phosphates with two R groups, one in the backbone and the other as a side group. They have good biocompatibility and a similarity to biomacromolecules such as DNA and RNA. Polyphosphoesters are divided into two different classes polyphosphonates with an alkyl or aryl R group and polyphosphates with an alkoxy or aryloxy R group. Polyphosphoesters are copolymerized with polyethers and polyesters to enhance their physical properties. They have been studied as scaffolds for bone tissue regeneration [8]. 

Physical and chemical mapping using AFM and ToF-SIMS are appropriate means for studying surfaces of flame retarded materials. Various interactions may take place between ammonium polyphosphate (APP), pentaerythritol (PER) and tetraethoxy-silane (TES). Whereas the reaction between APP and PER has been described [820], no direct reaction could be found between APP and TES. Marosi et al. [821] have reported imaging ToF-SIMS of APP-PER-ME-TES intumescent flame retarded (IFR) polypropylene. The image prepared on the basis of SiOjc ions proved the existence of a silicone layer between polymer and solid APP particles covered by PER. 

The problems encountered in attempting to crystallize some polyphosphate melts may well be a knotting of the strands of polyphosphate molecules. It has been adequately demonstrated that the physical behavior of strands of long-chain polyphosphates is highly dependent upon the ionic atmosphere surrounding these molecule-ions. 

Table 6.1. The Physical Properties of Calcium Polyphosphate Fibers Compared to...

The injection of ortho- or polyphosphate into feed water in a prehoiler system that contains an economizer wiU invariahly lead to serions economizer deposits when calcium is present. The physical condition of flow rates and water-metal interface temperatures, combined with the usual chemical environment will result in deposits that will he predominately tricalcium phosphate. 

---