Polysulfide ethers

The monomers with four methylene groups, on which the polysulfide ethers are based, are obtained from phenol and thiophene ... 

The compounds formed are converted to zwitterions with sodium methylate or ion exchangers, and these are then polymerized to polysulfide ethers with ring opening and loss of charge in what is known as death-charge polymerization, i.e.,... 

Nitro-filter cloths are composed of cellulose nitrate, which is an ester of cellulose. Any chemical compound that will saponify the ester will destroy the cloth. Caustic soda or potash in strengths of 2% at 70° C or over alkali sulfides, polysulfides and sulfohydrates or mixtures of ethyl alcohol and ether, ethyl, amyl and butyl acetates, pyridine, ferrous sulfates, and other reducing agents are detrimental to the cloth. 

Recently, the above mentioned model reaction has been extended to polycondensation reactions for synthesis of polyethers and polysulfides [7,81]. In recent reports crown ether catalysts have mostly been used in the reaction of a bifunctional nucleophile with a bifunctional electrophile, as well as in the monomer species carrying both types of functional groups [7]. Table 5 describes the syntheses of aromatic polyethers by the nucleophilic displacement polymerization using PTC. 

Various organic dihalides are employed in a reaction with sodium polysulfide to produce organic polysulfides (Thiokols). Ethylene dichloride, from the direct chlorination of ethylene, dichloroethyl formal, and /3,0 -dichlorodiethyl ether are the principal dihalides that have been employed in the process (44). These elastomeric polymers have been commercially available for a number of years, and many applications have been developed for them. They have excellent oil resistance and one of their principal uses has been in hose and tank linings in which that property is required. 

Many compounds have been tested as ignition quality improvers—additives which shorten the ignition delay to a desirable duration. An extensive review in 1944 (6, 43) listed 303 references, 92 dealing with alkyl nitrates and nitrites 61 with aldehydes, ketones, esters, and ethers 49 with peroxides 42 with aromatic nitro compounds 29, with metal derivatives 28 with oxidation and oxidation products 22 with polysulfides 16 with aromatic hydrocarbons nine with nitration and four with oximes and nitroso compounds. In 1950, tests at the U. S. Naval Engineering Experiment Station (48) showed that a concentration of 1.5% of certain peroxides, alkyl nitrates, nitroaikanes, and nitrocarbamates increased cetane number 20 or more units. 

Phenylacetamide has been obtained by a wide variety of reactions from benzyl cyanide with water at 250-260° 6 from benzyl cyanide with water and cadmium oxide at 240° 6 from benzyl cyanide with sulfuric acid 7 8 by saturation of an acetone solution of benzyl cyanide with potassium hydrosulfide 9 from benzyl cyanide with sodium peroxide 10 by electrolytic reduction of benzyl cyanide in sodium hydroxide 11 from ethyl phenyl-acetate with alcoholic 12 or aqueous 13 ammonia from phenyl-acetic acid with ammonium acetate 14 or urea 15 from diazoacetophenone with ammoniacal silver solution 16 from phenyl-acetic acid imino ether hydrochloride and water 17 from acetophenone with ammonium polysulfide at 215° 18 from benzoic acid 19 and by heating the ammonium salt of phenyl-acetic acid.20... 

PB PBI PBMA PBO PBT(H) PBTP PC PCHMA PCTFE PDAP PDMS PE PEHD PELD PEMD PEC PEEK PEG PEI PEK PEN PEO PES PET PF PI PIB PMA PMMA PMI PMP POB POM PP PPE PPP PPPE PPQ PPS PPSU PS PSU PTFE PTMT PU PUR Poly(n.butylene) Poly(benzimidazole) Poly(n.butyl methacrylate) Poly(benzoxazole) Poly(benzthiazole) Poly(butylene glycol terephthalate) Polycarbonate Poly(cyclohexyl methacrylate) Poly(chloro-trifluoro ethylene) Poly(diallyl phthalate) Poly(dimethyl siloxane) Polyethylene High density polyethylene Low density polyethylene Medium density polyethylene Chlorinated polyethylene Poly-ether-ether ketone poly(ethylene glycol) Poly-ether-imide Poly-ether ketone Poly(ethylene-2,6-naphthalene dicarboxylate) Poly(ethylene oxide) Poly-ether sulfone Poly(ethylene terephthalate) Phenol formaldehyde resin Polyimide Polyisobutylene Poly(methyl acrylate) Poly(methyl methacrylate) Poly(methacryl imide) Poly(methylpentene) Poly(hydroxy-benzoate) Polyoxymethylene = polyacetal = polyformaldehyde Polypropylene Poly (2,6-dimethyl-l,4-phenylene ether) = Poly(phenylene oxide) Polyp araphenylene Poly(2,6-diphenyl-l,4-phenylene ether) Poly(phenyl quinoxaline) Polyphenylene sulfide, polysulfide Polyphenylene sulfone Polystyrene Polysulfone Poly(tetrafluoroethylene) Poly(tetramethylene terephthalate) Polyurethane Polyurethane rubber... 

Such sulfinate compounds are water soluble and may be used as antiradiation drugs (see Section 7.4). Bis(sulfinato)trisulfanes may be converted to the corresponding bisalkyl esters by reaction with either diazomethane or a solution of BF3 in diethyl ether. When sodium polysulfide is apphed in equation (59) the resulting poly-sulfanes (equation 60) contain up to six sulfur atoms. However, bis(sulfinato)polysulfanes with more than four catenated sulfur atoms are unstable in water, and elemental sulfur is slowly precipitated. When the thiosulfonate RS(0)-(CH2)2-SS02C6H4Me was used in equations (59) and (60), the bis(sulfoxido)trisulfane [RS(0)-(CH2)2]2S3 resulted. ... 

Bifimctional mesityl ethers react with aqueous sodium polysulfide to give cyclic disulfanes and trisulfanes in high yields (equation 83). ... 

Studebaker identified the use of lithium aluminium hydride as a chemical probe.Under the right conditions it cleaves poly- and disulfide bonds, leaving the monosulfide intact. Lithium aluminum hydride reacts with polysulfides in an etheral solvent at moderate temperatures and then with a weak acid, the terminal groups are liberated as thiols and interior sulfur atoms are converted to hydrogen sulfide.Lithium... 

F Berthold, E-L Lindfors, G Gellerstedt. Degradation of Guaiacylglycerol- 3-guaiacyl Ether in the Presence of HS or Polysulfide at Various Alkalinities. Part I. Degradation Rate and the Formation of Enol Ether. Holzforschung 52 398 04, 1998. 

An ammonium polysulfide solution is prepared as in Section 3-A above to this solution is added 3.00 g K2PdCl4 (9.18 mmole) dissolved in 10 mL water. After shaking for 2 minutes, the initial black precipitate redissolves, and the solution is filtered through diatomaceous earth (filter aid or Celite) prewashed with ammonium hydroxide. The filtrate is stoppered and the reaction allowed to proceed 5 days at room temperature (ca. 22°). At this time, the solution is noticeably lighter in color and the product has precipitated. After filtration, the complex is washed with water, ethanol, diethyl ether, carbon disulfide, and... 

It was found that the reaction was a general one between aliphatic halogen compounds and water-soluble allaJine or Jkaline-earth polysulfides. Many different organic dihalides have been found to react with ium polysulfide to produce polymers. Commercially available dihalides include uthylene dichloride, propylene dichloride, dichloroethyl ether, tri ycol dichloride, and dichlorodiethyl formal. Dichlorodiethyl formal is the chief dihalide used in the polymers produced in the United States. It is made by the reaction of ethylene chlorohydrin with formaldehyde in the presence of an acidic catalyst ... 

The polysulfides derived from ethylene dichloride were not as elastomeric as natural rubber. It was foimd that increasing the spacing between reactive terminal groups improved the properties. Better products derived from bis(2-chloroethyl) ether were soon developed in the United States by the Thiokol Chemical Corp. 

The reaction of formaldehyde (paraformaldehyde) and hydrogen chloride (anhydrous) with tetrahydrofuran has been used to produce -chlorobutyl chlor-omethyl ether [15] a halide useful for preparing polysulfides [Eq. (3)]. 

---