Polymer resin strontium

There is bound to be one problem with resin glass polyalkenoate cement. Because the matrix is a mixture of hydrogel salt and polymer, lightscattering is bound to be greater than in the conventional material. Moreover, the zinc oxide-containing glass of class II materials is bound to be opaque. This makes it difficult to formulate a translucent material and is the reason why their use is restricted to that of a liner or base. However, the class II material cited will be radio-opaque because it uses strontium and zinc, rather than calcium, in the glass. 

As part of their formulation, polyacid-modified composite resins also contain a small fraction of basic glass filler of the type used in glass-ionomer cements [1]. Such glasses are typically calcium (or strontium) alumino-fluorosiUcates, and react with acids in the presence of water to release ions. The ions released, particularly calcium (or strontium) and aluminium react with the acid to form salts, which in the case of glass-ionomers, are insoluble because they form ionic crosslinks with the polymeric acid. The ions effectively insolubilize the acid-functional polymer chains by this reaction, as well as stiffening the material due to coil expansion and ion-binding. This type of chemistry is available to polyacid-modified composite resins once moisture is present, and these materials are designed for this reaction to occur in the early part of their existence. 

Gudyno and coworkers [26] reported the used of cation exchanges based on antimony polymers. The exchange resins were able to remove strontium. 

Calcium stearate, zinc stearate, potassium stearate and strontium stearate are used as lubricants to ijqirove the flow characteristics of polyolefin resins. These stearates also act as stabilizers by performing acid scavenging in polymers manufactured using acidic polymerization catalysts. 

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