Polythiols

N3P3(NHCH2CH=CH2)g undergoes photo reactions with polythiols. 

The most important attribute of the thiol-ene system is its insensitivity to oxygen thus, it is not inhibited by it. Another attractive feature is its very high cure speed. The disadvantage of the thiol-ene system is an unpleasant odor of the volatiles emitted from some polythiol compounds. ... 

It is possible to cross-link polyisobutylene and poly(isobutylene-isoprene) and chlorobutyl rubber by means of certain additives however, the physical properties of the vulcanizates prepared by conventional curing methods cannot be attained. The most promising results were obtained with chlorobutyl compounds containing thioether polythiols as prorads. ... 

The basis for cross-linking in the elastomers in these studies is the addition of thiols to olefmic double bonds. This reaction has been studied by a number of investigators.61-65 It has been shown that the addition reaction proceeds by a radical mechanism. The rate of cross-linking of polybutadiene can be strongly promoted by relatively small amounts of polythiols.66 For example, G(X) values increased from 5 (pure polybutadiene) to 29 when 1 wt. percent of dimercaptodecane was added and to more than 49 on the further addition of o-dichlorobenzene (see Table 5.2). 

Polythiols have been prepared by the reductive thiolation of C2H4—CO and C2H4— C3H6—CO copolymers, Eq. (22) 69). Typically a reaction temperature of 200 °C and a pressure of 80 mPa were used. 

The reduction of benzo-l,2-dithiole-3-thiones (77b) to various polythiols (74ACS(B)827, 63LA(661)84) may be accomplished by lithium (78BEP867155), lithium aluminum hydride, or by catalytic hydrogenation, and Raney nickel hydrodesulfurization gives products by complete elimination of sulfur (B-66MI43100). 

Fig. 2. Proteins that bind Cu(I). (a) Saccharomyces cerevisiae metallothionein (Cupl, pdb code laqr). Cupl binds up to seven Cu(I) ions (medium gray spheres) using 10 cysteine sulfur atoms (light spheres) in a polythiolate cluster (Peterson et al., 1996). All bonds shorter than 2.8 A are shown as dotted lines, (b) Cucumis sativus stellacyanin (pdb code Ijer). Both Cu(l) and Cu(ll) are bound by a pseudo-trigonal planar arrangement of (His)2Cys residues with an axial Gin ligand (Hart et al., 1996). In other cupredoxins such as plastocyanin, a Met residue is the axial ligand (Adman, 1991).

The intriguing circulene 18 has been prepared from the precursor 19 by initial exhaustive C-2 metalation, followed by introduction of elemental sulfur, and quenching with aqueous hydrochloric acid. This set of operations resulted in a polythiol, which was eventually converted to the target heterocycle 18 by vacuum pyrolysis <06AG(E)7367>. 

Clarkson T, Small H, Norseth T. 1973. Excretion and absorption of methylmercury after polythiol resin treatment. Arch Environ Health 26 173-176. 

A number of organotin polyesters, polyamides, polythiols, polyethers, and polyaminoesters have been synthesized from dialkyltin halides with dicarboxylic acids, diols, diamines, dithiols, urea, thiourea, amino acids, and hydroxyl acids involving polycondensation reactions. These polymers have potential applications as thermostabilizers for PVC. 

A polythiol compound manufactured by Hartman-Leddon Company, Philadelphia, Pennsylvania, U.S. 

Ruthenium complexes are of interest in light harvesting and electron transfer. Therefore many groups have been incorporating ruthenium complexes into a variety of macromolecular systems (for a review, see reference 236). We have successfully prepared ruthenium-containing polythiols, 102, and polyamines, 103, from bpy ruthenium complexes.237,238,239... 

C. Carraher, Q. Zhang, The Use of Ruthenium-Containing Polythiols for Solar Energy Conversion, in Metal-Containing Polymeric Materials, pp. 109-118, Plenum Publishing, New York, 1996. 

These dual UV/thermally curable conformal coatings are based on the ability to rapidly transform a liquid composition into a cross-linked solid by the free-radical polymerization of a polyfunctional acrylate in the presence of a low concentration of a polyfunctional thiol (1). Under these conditions, the polythiol functions partly by adding across the acrylic double bond and partly as a chain transfer agent in the acrylate homopolymeriza-... 

Loctite Ireland [139] patented use of onium salts for photopolymerization of polythiol-polyene compositions in 1986. Use of iodonium salts for... 

Add HNOj to Enzacryl polythiol or AH to form the azide, then add the enzyme, which will bond to the polymer by the NH2 group of lysine on the enzyme. 

Other types of curing systems for allyl-terminated urethane polymers were described by Kehr and Wszolek (176). Polyether and polyester urethane-ene systems were prepared by reaction of polyester or polyether dlols with allyl isocyanate or by reaction of isocyanate-terminated prepolymers with allyl alcohol. These urethane-ene systems can be cured by branched monomeric polythiols such as pentaerythritol tetrakis(thioglycolate) C(CH20C0CH2SH)4. 

Polythiol Reactant Polythiol Parts/ 100 Parts Sulfur by Weight Tensile Strength ipsi) Shore D Hardness... 

Many studies have appeared dealing with the properties of crosslinked polymer systems. These include adhesion of epoxy-acrylates onto tin-plate, adhesion of isocyanate and epoxy-resin coatings, adhesion of butadiene-acrylate rubbers onto metals, glass, and ceramics, adhesion of acrylic, thiol, and polyester resins to aluminium bodies, and the mechanical and physical properties of photo-crosslinkable poly(vinyl cinnamate), vinyl-divinyl copolymers,polythiols, acrylates, epoxies, and thiols,epoxy resins, polyesters on wood, ... 

Methylmercury compounds undergo extensive enterohepatic recirculation therefore, introduction of a nonabsorbable mercury-binding substance into the intestinal tract should facilitate their removal from the body. A polythiol resin has been used for this purpose in humans and appears to be effective. The resin has certain advantages over penicillamine. It does not cause redistribution of mercury in the body with a subsequent increase in the concentration of mercury in blood, and it has fewer adverse effects than do sulfhydryl agents that are absorbed. Clinical experience with various treatments for methylmercury poisoning in Iraq indicates that penicillamine, N-acetylpenicillamine, and an oral nonabsorbable thiol resin all can reduce blood concentrations of mercury however, clinical improvement was not clearly related to reduction of the body burden of methylmercury. 

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