Polymer impregnation

Sadegzadeh, M. and Kettle, R. J., Abrasion resistance of polymer impregnated concrete. Concrete, 32-34, May (1987). 

Applications Applications of UV/VIS spectrophotometry can be found in the areas of extraction monitoring and control, migration and blooming, polymer impregnation, in-polymer analysis, polymer melts, polymer-bound additives, purity determinations, colour body analysis and microscopy. Most samples measured with UV/VIS spectroscopy are in solution. However, in comparison to IR spectroscopy additive analysis in the UV/VIS range plays only a minor role as only a limited class of compounds exhibits specific absorption bands in the UV range with an intensity proportional to the additive concentration. Characteristic UV absorption bands of various common polymer additives are given in Scheirs [24],... 

UV/VIS spectrophotometry can also be used for extraction monitoring on the basis of the chromophore of functional classes and to follow up polymer impregnation with additives in scC02 [81]. 

Brass and bronze castings that are polymer impregnated should not be used. 

Class I. Felts and polymer impregnated felts Class 11. Microporous synthetic leathers Class III. Filled polymer films Class IV. Unfilled textured polymer films... 

In the polymer impregnated gels, some porosity typically remains. Although some copolymers of methyl methacrylate, butadiene and styrene have been used to impregnate silica, the best known system is still silica impregnated with polymethyl methacrylate (PMMA)150-153. While this type of hybrid was important at first, it has been surpassed by other methods of hybrid synthesis that are simpler, with fewer steps and shorter times. 

Just as wood may be impregnated with additives to improve physical properties, a variety of porous polymers also benefit from polymer impregnation. As more and more specialized applications arise, it is necessary to produce polymeric materials with very specific surface and bulk properties. The correct combination of properties may not be obtainable using a single polymer or copolymer. However, polymeric materials may be impregnated with an additive in order to modify the surface energy, bondability, hydro-philicity, and other important properties. 

The membrane extraction process mostly makes use of nonporous membranes. Such a membrane can be a liquid or a solid phase (a polymer impregnated with a liquid), which is placed between two... 

The third method is to grow the polymer into its desired shape and form. An insulating polymer impregnated with a catalyst system is fabricated into its desired form. This is then exposed to the monomer, usually a gas or a vapour. The monomer then polymerises on the surface of the insulating plaslic producing a thin film or a fibre. This is then doped in the usual manner. A variation of this technique is electrochemical polymerisation with the conducting polymer deposited on an electrode either at the polymerisation stage or before the electrochemical polymerisation. 

Strength and Elastic Modulus of Polymer Impregnated Concrete, Cem. Concr. Res. (1971) 1, 631-644. 

Pastes inpregnated with PMMA or sulphur are still sufficiently permeable to water that expansion occurs on long exposure (F46). In polymer-impregnated (S108) and MDF (R64) cement pastes, there is evidence of interaction between Ca ions and carboxylate and possibly other groups of the polymer. In MDF pastes made with calcium aluminate cement, the polymer (PVA) was found to inhibit the normal hydration reactions of the cement, but to react with Ca and AH to give an ionically cross-linked polymer and calcium acetate. TEM showed the material to be essentially a dispersion of grains of clinker or hydration products in a continuous polymer matrix. 

Krieg HM, Breytenbach JC, and Keizer K. Chiral resolution by B-cyclodextrin polymer impregnated ceramic membranes. J. Membr. Sci. 2000 164 177-185. 

The impregnation of wood by polymers with TBT functional groups offers a viable route to the preparation of bioactive wood— polymer composites with a number of advantages. Polymer impregnation may be expected to improve the strength properties and dimensional stability of wood in water. The controlled release of the toxic TBT moiety, chemically linked to the polymer located within the wood, can increase the service life of wood while ensuring min-... 

Dimensional Stability. As expected, the antishrink efficiency (ASE) is increased, and the amount of water absorbed is decreased because of polymer impregnation. Table II summarizes the results of... 

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