Encapsulation and Impregnation

The epoxy-resin procedures described here are intended for single polished sections and polished thin sections of selected sieve fractions of whole or fragmented clinkers, rocks, bricks, ceramics, concrete, and many other materials. The desirable properties of an epoxy-encapsulating and -impregnating medium are  

Insolubility of the hardened epoxy in acetone, xylene, alcohol, or other similar solvents. 

Hardness sufficient to promote the development of a relatively flat surface during grinding and to minimize the development of particle relief during polishing. 

Quick setting, within a few hours at most, with neither inordinate heat generation nor excessive shrinkage. Some epoxies and other cements, such as cyanoacrylate ester (Super Glue ), which harden in only a few minutes, are recommended in circumstances where quick answers are needed. 

Place the polyethylene container with its contents in a vacuum container and evacuate for a few minutes. Epoxy will bubble under vacuum and, if the container is too full, will overflow. Periodically breaking the vacuum will reduce the bubbling tendency. Slowly release the vacuum, allowing atmospheric pressure to force the resin into the sample. 

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The largest application of epoxies is in embedding applications (potting, casting, encapsulating, and impregnating), in molded parts, and in laminated constructions such as metal-clad laminates for printed circuits and unclad laminates for various types of insulating and terminal boards. Molded epoxy parts have excellent dimensional stability. 

Nii, S. Masutani, M. Takeuchi, H. Extraction of heavy metal ions using encapsulated extractant-impregnated resins. In Solvent Extraction for the 21st Century (Proceedings of ISEC 99), Vol. 2, eds. M. Cox, M. Hidalgo, and M. Valiente, Society of Chemical Industry, London, 2001, pp. 1279-1283. 

Agricultural pesticides exist in a variety of forms gases, liquids, emulsions, granules, powders, pellets, aerosols, encapsulates, and even impregnated... 

Many polymeric systems have been adapted for applications in which they become an integral part of electrical equipment. Polymers may be used, for example, to protect components of electrical systems or to enhance the mechanical and electrical integrity of electrical apparatus. These applications are referred to as vacuum pressure impregnation, potting, encapsulation, and casting some of these are illustrated by the following examples. 

Lord, A.E., Koerner, R.M., 1986. Diffusion of water from soils encapsulated by impregnated geotextiles (MESLs). Geotextiles and Geomembranes 3 (1), 3—27. 

Virosomes are virus-mimicking systems that contain liposomal bilayer and pH-dependent protein impregnated in the liposomal wall. Virosomes are produced by a detergent dialysis procedure. Many researchers have demonstrated that the virosomes facilitate the leakage of the encapsulated drugs from the endosomes into the cytoplasm. This is, however, complicated technology and, so far, no virosome products are used in the clinical practice. 

For the preparation of CoSalophen Y the Co—Y was impregnated by salicy-laldehyde, and 1,2-phenylenediamine in methanol was added slowly to the mixture.107 This was a successful encapsulation of a salen-type complex with larger diamine than the ethylenediamine, a successful preparation of an encaged metal-salen complex by the intrazeolite ligand synthesis method, and a successful intrazeolite synthesis using two different precursor molecules. 

Silicone resins find use as insulating varnishes, impregnating and encapsulating agents and in industrial paints. 

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