Akzo Nobel N.v.

Rabindra Nath Datta

Auke Gerardus Talma

Arie Jacob De Hoog

Andreas Herman Hogt

Rudolf F De Block

Johannes Hermanus Wilbrink

Berend Jan Dijk

Andre Steenbergen

Martinus Gerhardus Johannes Hondeveld

Nicolaas Maria Huntink

The invention relates to a silica-filled, sulfur-vulcanizable rubber composition comprising an unsaturated rubber, 20 to 100 phr of a silica, 1.6 to 8 phr of a silica coupling agent, 0.05 to 5 phr of an antidegradant, 0.1 to 5 phr of a vulcanization accelerator, 0.1 to 10 phr of sulfur, and 0.5 to 5 phr of a quinone diimine, with the proviso that the antidegradant is not a quinone diimine. The invention also relates to a vulcanization process comprising mixing and heating said rubber composition and to rubber articles, such as pneumatic tires, comprising the rubber vulcanizate obtained by said process.

Silica-filled rubbers comprising a quinone diimine

A vulcanized rubber composition which comprises the vulcanization reaction product of 100 parts by weight of at least one natural or synthetic rubber; 0.1 to 25 parts by weight of sulfur and/or a sufficient amount of a sulfur donor to provide the equivalent of 0.1 to 25 parts by weight of sulfur; 10-100 parts by weight of at least one silica filler; 0.1 to 5 parts by weight of at least one anti-reversion coagent comprising at least two groups selected from citraconimide and/or itaconimide groups; and a sufficient amount of a least one cure-improving resin to significantly increase the delta torque of the rubber composition during the vulcanization process as compared to the delta torque of a similar rubber composition in the absence of the cure-improving resin, is disclosed. Also disclosed is a process for the vulcanization of this rubber composition, and articles of manufacture comprising the vulcanized rubber composition. The invention is useful for the partial or complete replacement of silane coupling agents in silica-filled rubber compositions.

Cure parameters in rubber vulcanization

Zinc carboxylic acid complexes in sulfur-vulcanized rubber compositions

Novel metal salts of (poly)citraconimide and (poly)itaconimide carboxylic acids, and a vulcanizable rubber composition comprising these novel metal salts and which, upon vulcanization, exhibits improved dynamic properties, are disclosed. Also disclosed are a sulfur-vulcanization process carried out in the presence of these metal salts and the product of said vulcanization process. The novel metal salts are represented by the formulas I and II: ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3 are independently selected from hydrogen, C.sub.1 -C.sub.18 alkyl groups, C.sub.3 -C.sub.18 cycloalkyl groups, C.sub.6 -C.sub.18 aryl groups, C.sub.7 -C.sub.30 aralkyl groups and C.sub.7 -C.sub.30 alkaryl groups and R.sub.2 and R.sub.3 may combine to form a ring when R.sub.1 is hydrogen; R.sub.4 is selected from divalent, trivalent or tetravalent linear or branched radical chosen from a C.sub.1 -C.sub.18 alkyl, C.sub.2 -C.sub.18 alkenyl, C.sub.2 -C.sub.18 alkynyl, C.sub.3 -C.sub.18 cycloalkyl, C.sub.3 -C.sub.18 polycycloalkyl, C.sub.6 -C.sub.18 aryl, C.sub.6 -C.sub.30 polyaryl, C.sub.7 -C.sub.30 aralkyl, C.sub.7 -C.sub.30 alkaryl, oligomers of one or more of these radicals, and which radicals may optionally contain one or more of oxygen, nitrogen, silicon, phosphorus, sulfur, sulphone, sulfoxy and boron; B and B.sup.1 are independently selected from the following hetero atoms: oxygen and sulfur, X is a metal selected from Mg, Ti, Zn, Cd, Sr, Ba, Fe, V, Sn, Te, Mo, Mn, Pb and Al, m is an integer from 1-3 and n is an integer of from 2-4.

Anti-fatigue coagents for rubber vulcanization

Vulcanized rubber compositions comprising anti-reversion coagent and a

Sulfur-vulcanized rubber compositions comprising substituted succinimide

A rubber composition which is the vulcanization reaction product of a rubber, sulfur or a sulfur donor and particular anti-reversion coagents, is disclosed. The anti-reversion coagents only partially react under sulfur-vulcanization reaction conditions up to optimum cure, and, after optimum cure, form cross-links bonded to the sulfur cross-linked rubbers by carbon-carbon linkages. Also disclosed are a vulcanization process carried out in the presence of the anti-reversion coagents and the use of these anti-reversion coagents in the sulfur-vulcanization of rubbers. The anti-reversion coagents of the disclosure provide sulfur-vulcanized rubbers having significantly improved physical properties.

Anti-reversion coagents for rubber vulcanization

Growing community of inventors

Deventer, Netherlands

Rabindra Nath Datta