Poly sulfide Thiokol

Odian et a1 (Refs 113,133 150) showed that the deflagration rates of many composite AP solid propints were affected by gamma doses of 5 x I07 R. Two poly sulfide-based proplnts (Thiokol TP-L-3014 and TP-L-3014a) showed rate decreases, polyurethane (Thiokol TP-6-3129), polyacrylate (Hercules HES-6420) and polyacrylonitrile (HES-6648) based proplnts showed increases, while hydrocarbon (Thiokol TP-H-3062) and cellulose acetate (Hercules HES-5808) proplnts showed no changes in deflagration rate. Since the composite propint formulations contain various additives besides the binder and oxidizer, an effort was made to determine the effect of radiation on the deflagration rates of binder and oxidizer separately and independent of additives... 

A method, using differential scanning calorimetry, has been developed to estimate quantitatively orthorhombic and monoclinic sulfur in sulfur materials. Sulfur cooled from the melt at 120°C immediately gives monoclinic sulfur which reverts to orthorhombic sulfur within 20 hr. Limonene, myrcene, alloocimene, dicyclopentadiene, cyclododeca-1,5,9-triene, cycloocta-1,3-diene, styrene, and the polymeric polysulfides, Thiokol LP-31, -32, and -33 each react with excess sulfur at 140° C to give a mixture of poly sulfides and unreacted sulfur. In some cases substantial amounts of this unreacted sulfur may be held indefinitely in a metastable condition as monoclinic sulfur or S8 liquid. Limonene, myrcene, and dicyclopentadiene are particularly effective in retarding sulfur crystallization. 

Thiokol A, Eihanite, Perdu ren. The first commercial poly-sulfide polymer, prepd from ethylene dichloride and sodium polysulfide. Sulfur content 84% d about 1.6. Mixes with natural rubber. Cured polymer retains unpleasant odor irritating fumes evolve during manuf. Stable to the usual organic solvents and dil mineral acids. Unstable to alkalies and oxidizing substances. Of low tensile strength and abrasion resistance. Not recommended where tropic or arctic climates prevail,... 

Many of the sealants have been prepared using Thiokol LP -2, LP -32 or LP -31 as the base poly sulfide liquid polymer the chemistry, cure mechanisms, reinforcement, and applications will thus be restricted to these polymers. The chemistry and applications of polysulfide polymers, crudes, water dispersions, and various liquid polymers are covered completely in extensive bibliographies by Berenbaum and Pa-nek. 

Poly sulfides were first discovered and patented in about 1927 by J.C. Patrick by accident in attempting to develop antifreeze. The polymer was called Thiokol A, a condensation reaction of ethylene dichloride and sodium tetrasulfide, for which manufacturing began in 1929 [1]. This elastomer was quite difficult to process due to its variability and thermoplastic nature, leading to the discontinuation of manufacture after improved grades were developed. 

The resistance of these two types of polysulfide to highly aromatic solvents and ketones commonly encountered is outstanding. The resistance of Thiokol FA and ST to a few of these solvents is shown in Table 11.3. Additional chemical resistance information on poly sulfides may be found in Chemical Resistance Guide for... 

Thiokol Poly(ethylene chloride-co-sexlium sulfide) E. I. du Pont de Nemoms... 

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