Heat glue

While most organic coatings absorb somewhere in the IR, there are advantages to its selectivity. Leather is largely transparent in the region from 1 to 1.5 um. This makes it possible to selectively heat glue on the inside of a shoe and cause it to dry... 

Being thermoplastic polymers they may be heated and softened again and again. Supplied as short pencil-shaped sticks they are intended to be applied from electrically heated glue guns. Only the required amount is squirted from the gun any surplus is left inside to cool and be reused later. Since the joint must be closed before the melt can appreciably cool it is only really suitable for small fabrications, the strength of bonds is somewhat limited. 

Fluoridation of potable water suppHes for the prevention of dental caries is one of the principal uses for sodium fluoride (see Water, municipal WATER treatment). Use rate for this appHcation is on the order of 0.7 to 1.0 mg/L of water as fluoride or 1.5 to 2.2 mg/L as NaF (2). NaF is also appHed topically to teeth as a 2% solution (see Dentifrices). Other uses are as a flux for deoxidiziag (degassiag) rimmed steel (qv), and ia the resmelting of aluminum. NaF is also used ia the manufacture of vitreous enamels, ia pickling stainless steel, ia wood preservation compounds, caseia glues, ia the manufacture of coated papers, ia heat-treating salts, and as a component of laundry sours. 

Casein is used to fortify flour, bread, and cereals. Casein also is used for glues and microbiological media. Calcium caseinate is made from a pressed casein, by rinsing, treating with calcium hydroxide [1305-62-0], heating, and mixing foUowed by spray drying. A product of 2—4% moisture is obtained. 

The chemical materials requited for this process iaclude the cormgatiag adhesive, 1—1.2 MPa (150—175 psi) process steam to provide heat to set the cormgator adhesive, possible coatings appHed to the surface of the linerboard facings, possible chemicals impregnated into the linerboard and/or medium, the manufacturer s (glue) joint adhesive, and the printing ink (see Inks). 

In addition to poly(methyl methacrylate) plastics and polyacrylonitrile fibres, acrylic polymers find widespread use. First introduced in 1946, acrylic rubbers have become established as important special purpose rubbers with a useful combination of oil and heat resistance. Acrylic paints have become widely accepted particularly in the car industry whilst very interesting reactive adhesives, including the well-known super-glues are also made from acrylic polymers. 

Epoxy resins have outstanding mechanical and electrical properties, dimensional stability, resistance to heat and chemicals, and adhesion to other materials. They are used for casting, potting, encapsulation, protective coatings, and adhesives. Epoxy glues separate the resin from the curing. igciU to be mixed just prior to use. 

The addendum (represented by heater, glue spots and A1 tubes) gave a negligible contribution to the total heat capacity (see Table 12.3). The thermistor heat capacity was instead considered as part of the sample. The whole experiment was surrounded... 

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