Corks softening

Succinamide. NHoCOCH2 CH2CONH2. (Method 2(a)). Add 5 ml. (5 8 g.) of dimethyl succinate to a mixture of 50 ml. of water and 25 ml. of concentrated [dy o-88o) aqueous ammonia solution in a 150 ml. conical flask. Cork the flask and shake the contents the dimethyl succinate rapidly dissolves to give a clear solution. Allow the solution to stand after about i hour the succinamide starts to crystallise, and then continues to separate for some time. Next day, filter off the succinamide at the pump, wash with cold water, and drain. Recrystallise from water, from which the succinamide separates as colourless crystals the latter soften at 240° and melt at 254 -255° with... 

It should then be softened by rolhng in a cork press or by wrapping it in paper and roUing under the foot. 

Cork, a natural material - the bark of the Mediterranean cork oak tree. It is largely air cells and the fibrous cell walls have a high resin content. When baked, the resin softens and welds the pieces of bark into a comparatively homogeneous mass, which is sliced into blocks, commonly 50, 75 and 100 mm thick. 

A brand new cork, before pressing or rolling, should fit only about one-quarter of the way into the neck of the flask or vial. Then you roll the lower half of the cork on your clean benchtop to soften and press the small end. Now stopper your container. The cork will slowly expand a bit and make a very tight seal (Fig. 28). 

A piece of the polymer (about 1 g) is placed in a 500 ml beaker, containing boiling water. At this temperature, the polystyrene softens and is foamed by the vaporizing pentane. The test piece is held below the surface of the water for 5 min with the aid of a piece of bent wire and is then removed.The foamed material obtained in this manner is dipped into a graduated cylinder, containing methanol, in order to determine its approximate volume it is also weighed after drying in a vacuum desiccator.The density is found to be below 0.1 g/cm (cf.,cork has a density of 0.2 g/cm ). 

After removal, the cork is air-dried for a lime, then boiled to soften it and In remove some of the tannin. The outer part of the bark is scraped off, and the rest pressed out Oat and dried. It is then ready to ship. 

Two points must be borne in mind when selecting a cork stopper. In the first place, the cork should be examined for flaws unless corks of the highest quality are employed, they are liable to have deep holes, which render them useless. In the second place the cork should fit into the socket to only about one-quarter of its length. It should then be softened by rolling in a cork press or by wrapping it in paper and rolling under the foot. 

Insert the prepared sample thermometer in the test tube, supporting it with a notched cork stopper so that the lower end of the bulb is 25.4 mm from the bottom of the test tube. Place the test tube in the bath so that the bottom of the thermometer bulb is 50.8 mm from the bottom of the beaker the top of the bulb should be about 25.4 to 38.1 mm below the liquid level of the bath. Stir the bath to keep its temperature uniform throughout. Observe the sample thermometer, and record as the softening point the reading at which the elongated drop of sample on the end of the bulb first becomes constricted (see Fig. 39). Report the softening point to the nearest 1.0°. 

Use Production of polyurethane and unsaturated polyester resins, triethylene glycol textile softener petroleum solvent extraction dehydration of natural gas, plasticizers, and surfactants solvent for nitrocellulose and many dyes and oils humectant for tobacco, casein, synthetic sponges, paper products cork compositions, bookbinding adhesives, dyeing assistant, cosmetics, antifreeze solutions. 

Products and Uses A conditioner, humectant (moisturizer), and cleaner used in fabric softeners, tobacco moisturizer, synthetic sponges, paper products, corks, book-binding adhesives, cosmetics, rug cleaners, upholstery cleaners, floor polish, furniture polish, as disinfectant, and antifreeze. 

Uses Prod, of polyurethane and unsat. polyester resins, triethylene glycol, morpholine, paints textile softener, lubricant solvent for nitrocellulose, dyes, oils, printing inks extraction solvent dehydration of natural gas, plasticizers, surfactants humectant for tobacco, casein, and syn. sponge cork compositions bookbinding adhesives dyeing assistant cosmetics antifreeze ingred. PU chain extender processing aid ac-... 

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