Binder, dextrins

A friction primer compn for an airplane flare contains 14 parts K chlorate 1.6 parts charcoal in 0.3 parts of binder (dextrin). Modified scratch sensitive mixts contg thermite produce very high temps and can ignite some smoke mixts without an intermediate starter (Ref 54, p 5-46)... 

Our samples were prepared by using a composite rod made of graphite and LajOs. llie materials were mixed with a binder (dextrin), partially dried and pressed into a rod. After annealing at 150 °C, the rod was heated to 1,400 C for 2h. The soot produced by arc vaporization of the rod under helium at 200 Torr was extracted with toluene, and the extract was washed with diethyl ether and dried. The resulting powder was analysed using mass spectrometry and electron paramagnetic resonance (EPR) spectroscopy. 

Notes All the above formuXas total 100 parts each by weight, with tbs exception of the binder (dextrin), which is in excess and printed in parentheses where such is the case. Thus the measurcasnts can be taken either as "parts by weight" or psroentagss by weight. Three... 

Pyrotechnic mixtures may also contain additional components that are added to modify the bum rate, enhance the pyrotechnic effect, or serve as a binder to maintain the homogeneity of the blended mixture and provide mechanical strength when the composition is pressed or consoHdated into a tube or other container. These additional components may also function as oxidizers or fuels in the composition, and it can be anticipated that the heat output, bum rate, and ignition sensitivity may all be affected by the addition of another component to a pyrotechnic composition. An example of an additional component is the use of a catalyst, such as iron oxide, to enhance the decomposition rate of ammonium perchlorate. Diatomaceous earth or coarse sawdust may be used to slow up the bum rate of a composition, or magnesium carbonate (an acid neutralizer) may be added to help stabilize mixtures that contain an acid-sensitive component such as potassium chlorate. Binders include such materials as dextrin (partially hydrolyzed starch), various gums, and assorted polymers such as poly(vinyl alcohol), epoxies, and polyesters. Polybutadiene mbber binders are widely used as fuels and binders in the soHd propellant industry. The production of colored flames is enhanced by the presence of chlorine atoms in the pyrotechnic flame, so chlorine donors such as poly(vinyl chloride) or chlorinated mbber are often added to color-producing compositions, where they also serve as fuels. 

Starch pyrodextrins and British gums have the abiUty, in aqueous dispersion, to form films capable of bonding like or unlike materials. Thus, they have uses as adhesives for envelopes, postage stamps, and other products. These dextrins are used in glass-fiber siting to protect the extmded fiber from abrasion, and as binders for metal core castings, water color paints, briquettes, and many other composite materials (qv). 

Hydroxyethylstarch is widely used with synthetic latexes in the surface sizing of paper and as a coating binder. For these uses, the hydroxyethylstarch is acid-thinned, oxidized, or dextrinized. Hydroxypropylstarch is used in foods to provide viscosity stabiHty and to ensure water-holding during low temperature storage. 

An expl prepd by mixing Ba nitrate, diarcoal and Amm picrate or amorph P 1888 An expl consisting of 3p Ba nitrate and lp AN, together with a small quant of dextrin or gum as binder... 

More exotic effects call for more exotic materials, and considerable effort has gone into formulating compositions that are both spectacular in effect and safe to produce and handle. Thus a 30 mm fountain might contain mealed (or hue) gunpowder, potassium nitrate, sulfur, charcoal, antimony trisulhde, barium nitrate, hue aluminium and flitter aluminium with a dextrin binder. This composition is certainly a good deal more complicated than that used for sparklers but is relatively safe to produce and gives a good burst of white sparks. 

Dextrine is widely used as a binder in the fireworks industry. Water is used as the wetting agent for dextrine, avoiding the cost associated with the use of organic solvents. 

Quickmatch. Fast burning fuse made by impregnating cotton wick with mealed (finely powdered) or unmealed BkPdr. Gum arabic or dextrin is used as a binder. Quickmatch is highly sensitive to moisture and must be kept dry for proper functioning. It burns almost instantaneously when confined (Ref 23, pp 2-21 to 2-22 USSpec JAN-Q-378)... 

A safety match requires for its ignition a rubbing on a "striking strip" which is covered with mixture such as consisting of red phosphorus 53, Sb sulfide 42 charcoal 5% in a binder such as NC lacquer, animal glue, dextrin, casein, plus hardener. Sb sulfide and charcoal serve as extenders to the phosphorus. 

The head of a safety match consists of K chlorate 45-55, animal (hide) glue (as a binder) 9-11, sulfur or rosin 3-5, extender (starch, dextrin) 2-3, neutralizer (ZnO.or Ca carbonate) 45-55, infusorial earth 5-6 other siliceous filler 15-32%. Fractional percentages of a soluble burning rate catalyst, such as K di-chromate, also soluble dye stuffs, etc... 

Friction Igniter consists of a primer cup contg a mixt of K chlorate, charcoal and dextrin binder. A loop of wire coated with red phosphorus in shellac extends thru this cup... 

Ml Fire Starter, listed in Ref 57, p 73, is described in Ref 31b. Its match compn is formulated accdg to MIL-STD-585 (Formula 20 of Ref 57, p 361 K chlorate 50, Sb sulfide 30 dextrin 20%) and the striker accdg to MIL-STD-537 (Formula 27 of Ref 57, p 356 Red p 50, dextrin 20 sand with sharp edges 30%. A hot and relatively slow flame, affording transfer of the fire to the substratum into which the match button is embedded, can be obtd with formulation contg small amts of nonhydrophilic binders such as Formula 22 of Ref 57, p 355 ... 

Dextrin also has been and is now used as a binder in various pyrotechnic compos (Ref 11) Davis (Ref 5, pp 62ff) gives numerous examples. As a binder a desensitizer it has been used in primer compns, as for example in a friction primer used for an airplane flare (Ref 5, p 454), or in a compn. for electric primers consisting of K chlorate 88, charcoal 10 dextrin 2% (Ref 9, p 118). As a fuel dextrin was used in some commercial expls, such as Nobelit "Fordit (Ref 2, p 407). In some gelatine expls, such as "Safety Jelly Dynamite (Ref, p 407), a paste called "glue-dextrine-glycerine jelly was used... 

Dextrin - [COLORANTS FOR FOOD,DRUGS, COSMETICS AND MEDICALDEVICES] (Vol 6) - [EXPLOSIVES AND PROPELLANTS - EXPLOSIVES] (Vol 10) -as pyrotechnic binders [PYROTECHNICS] (Vol 20) -use in electroplating [ELECTROPLATING] (Vol 9)... 

Binder or Aggiutinont is a material, such as asphalt or bitumen, dextrin, starch, flow, glue, fossil gums, gelatin, milk sugar, petrolatum, resins, shellac, stearin, paraffin wax, sugar, syn-... 

Typical scratch mixtures are the pair A) potassium chlorate 6, antimony sulfide 2, glue 1 and (B) powdered pyrolusite (Mn02) 8, red phosphorus 10, glue 3, recommended by Weingart and the pair (A) potassium chlorate 86, antimony sulfide 52, dextrin 35 and (B) red phosphorus 9, fine sand 5, dextrin 4, used with gum arabic as a binder, and recommended by A. F. Clark. 

The components of star composition are mixed intimately and dampened uniformly with some solution which contains a binder, perhaps with gum-arabic water, perhaps with water alone if the composition contains dextrin, perhaps with alcohol if it contains shellac. Several different methods are used for forming the stars. 

Binders used include gum arabic, gum tragacanth, glue, dextrin, sodium alginate, rubber cement, and karaya gum. 

Dextrins are produced by dry heating (roasting) starch in the presence of an acid catalyst. They are produced in a range of viscosity and color specifications. Dextrins are primarily used as adhesives in paper conversion, such as laminating and envelope production. A low-viscosity dextrin is used in Europe as a total chlorine free (TCF) coating binder for application on TCF paper. 

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