A desulfurized rubber obtained by mixing a desulfurization agent and a vulcanized rubber, the desulfurization agent containing a compound represented by any one of the following formulae (1) to (4):

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wherein R.sub.1 to R.sub.8 each independently represent a hydrogen atom, an oxygen atom, or an alkyl group. It is preferable that the desulfurization agent contains at least one selected from the group consisting of 2,2′-dithiodianiline and 4,4′-dithiodianiline.

Preparing a microbially desulfurized crumb rubber includes combining microorganisms capable of breaking crosslinked sulfur bonds, sulfur-containing crumb rubber, and a salt solution to yield a mixture; combining a buffer with the mixture to yield a buffered mixture, thereby adjusting a pH of the mixture; providing oxygen to the buffered mixture; incubating the buffered mixture for a length of time to yield a microbially desulfurized mixture; combining the microbially desulfurized mixture with bitumen to yield a precursor; and heating the precursor to yield the microbially desulfurized crumb rubber. The microbially desulfurized crumb rubber can be combined with bitumen to yield a modified bitumen. The modified bitumen can be combined with asphalt to yield a modified asphalt.

Preparing a microbially desulfurized crumb rubber includes combining microorganisms capable of breaking crosslinked sulfur bonds, sulfur-containing crumb rubber, and a salt solution to yield a mixture; combining a buffer with the mixture to yield a buffered mixture, thereby adjusting a pH of the mixture; providing oxygen to the buffered mixture; incubating the buffered mixture for a length of time to yield a microbially desulfurized mixture; combining the microbially desulfurized mixture with bitumen to yield a precursor; and heating the precursor to yield the microbially desulfurized crumb rubber. The microbially desulfurized crumb rubber can be combined with bitumen to yield a modified bitumen. The modified bitumen can be combined with asphalt to yield a modified asphalt.

A depolymerizer is formed by grafting thiol groups on parts of the double bonds of a polymer of linear conjugated diene monomer. The linear conjugated diene monomer can be 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, 2-methyl-1,3-pentadiene, 2,3-dimethyl-1,3-pentadiene, 2-phenyl-1,3-butadiene, or 4,5-diethyl-1,3-octadiene. The depolymerizer has a weight average molecular weight of 1000 to 400000.

A depolymerizer is formed by grafting thiol groups on parts of the double bonds of a polymer of linear conjugated diene monomer. The linear conjugated diene monomer can be 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, 2-methyl-1,3-pentadiene, 2,3-dimethyl-1,3-pentadiene, 2-phenyl-1,3-butadiene, or 4,5-diethyl-1,3-octadiene. The depolymerizer has a weight average molecular weight of 1000 to 400000.

The present invention concerns new precursors of recyclable cross-linked diene elastomers comprising at least one furanyl group along the chain and comprising chain-end units with furanyl groups, their use in the preparation of said recyclable elastomers and their process of preparation. The invention also concerns new recyclable cross-linked diene elastomers, their preparation process and their uses.

Disclosed are compositions comprising a liquid carrier, a polysulfide rubber curing agent, a metal cation, and an ionic liquid. Also disclosed are methods for curing a surface of an uncured polysulfide rubber. These methods involve applying the disclosed compositions to the surface of the uncured polysulfide rubber.

Disclosed are compositions comprising a liquid carrier, a polysulfide rubber curing agent, a metal cation, and an ionic liquid. Also disclosed are methods for curing a surface of an uncured polysulfide rubber. These methods involve applying the disclosed compositions to the surface of the uncured polysulfide rubber.

Urea-terminated polybutadiene polymers and polybutadiene acrylonitrile copolymers useful as both accelerators and tougheners are disclosed for use in epoxy formulations cured with dicyandiamide. The inventive urea-terminated polymers achieve comparable toughness in cured epoxy formulations when compared to that achieved with traditional polymeric or rubber tougheners with little to no change in glass transition temperature. Viscosity improvement and stability over time are also an advantage. A method of preparation emphasizing aspects of reaction stoichiometry is also disclosed.

Recycled rubber is provided, which is formed by depolymerizing 100 parts by weight of rubber and 0.5 to 10 parts by weight of modifier, wherein the modifier is formed by reacting (a) R.sup.1-M, (b) double bond monomer, (c) ethylene sulfide, and (d) polymerization terminator, wherein R.sup.1 is C.sub.4-C.sub.16 alkyl group, M is Li, Na, K, Ba, or Mg and (b) double bond monomer is 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, 2-methyl-1,3-pentadiene, 2,3-dimethyl-1,3-pentadiene, 2-phenyl-1,3-butadiene, 4,5-diethyl-1,3-octadiene, styrene, 1-ethylene naphthalene, 3-methylstyrene, 3,5-diethylstyrene, 4-propylstyrene, 2,4,6-trimethylstyrene, 4-dodecylstyrene, 3-methyl-5-n-hexylstyrene, 4-phenylstyrene, 2-ethyl-4-benzylstyrene, 3,5-diphenylstyrene, 2,3,4,5-tetraethyl styrene, 3-ethyl-1-vinylnaphthalene, 6-isopropyl-1-vinylnaphthalene, 6-cyclohexyl-1-vinylnaphthalene, 7-dodecyl-2-vinylnaphthalene, α-methyl styrene, or a combination thereof.