RUBBER COMPOSITION THAT CAN BE USED FOR MANUFACTURING A TYRE OF WHICH THE COMPOSITION COMPRISES A STARCH AND AN AQUEOUS OR WATER-SOLUBLE PLASTICIZER
A rubber composition based on a diene elastomer, a crosslinking system, and a reinforcing filler is provided, as well as a process for obtaining the composition. The composition includes a starch in a proportion of from 10 to 50 phr (parts by weight per hundred parts of elastomer) and an aqueous or water-soluble plasticizer in a proportion of from 3 to 30 phr. The aqueous or water-soluble plasticizer is water or a mixture of water and glycerol, in which the water is predominant by weight in the aqueous or water-soluble plasticizer. The composition can be used for preparing calendered or profiled tyre-related products, such as a tyre tread, for example.
1 - 19 . (canceled)
20 . A rubber composition comprising:
a diene elastomer;
a crosslinking system;
a reinforcing filler;
a starch in a proportion of from 10 to 50 phr (parts by weight per hundred parts of elastomer); and
an aqueous or water-soluble plasticizer in a proportion of from 3 to 30 phr,
wherein the aqueous or water-soluble plasticizer is water or a mixture of water and glycerol, in which the water in the mixture is predominant by weight in the aqueous or water-soluble plasticizer.
21 . The rubber composition according to claim 20 , wherein the proportion of the starch ranges from 15 to 40 phr.
22 . The rubber composition according to claim 20 , wherein the proportion of the aqueous or water-soluble plasticizer ranges from 7 to 28 phr.
23 . The rubber composition according to claim 20 , wherein the starch includes a minimum of 10% of amylose.
24 . The rubber composition according to claim 23 , wherein the starch includes a minimum of 15% of amylose.
25 . The rubber composition according to claim 24 , wherein the starch includes a minimum of 20% of amylose.
26 . The rubber composition according to claim 20 , wherein the aqueous or water-soluble plasticizer is water.
27 . The rubber composition according to claim 20 , wherein reinforcing filler includes predominantly carbon black.
28 . The rubber composition according to claim 20 , wherein the reinforcing filler includes predominantly silica.
29 . The rubber composition according to claim 20 , wherein the reinforcing filler includes a blend of carbon black and silica.
30 . The rubber composition according to claim 20 , wherein the rubber composition is in a non-crosslinked state.
31 . The rubber composition according to claim 20 , wherein the rubber composition is in a crosslinked state.
32 . The rubber composition according to claim 20 , wherein the rubber composition is formed into a calendered or profiled product used in manufacturing a tyre.
33 . The rubber composition according to claim 20 , wherein the rubber composition is formed into a tyre.
34 . A process for obtaining a rubber composition, the process comprising steps of:
thermomechanical kneading of constituents of a composition, the constituents excluding a vulcanization system; and
adding to the composition, during the thermomechanical kneading step, a starch in a proportion of from 10 to 50 phr and an aqueous or water-soluble plasticizer in a proportion of from 3 to 30 phr, to obtain a rubber composition,
wherein the aqueous or water-soluble plasticizer is water or a mixture of water and glycerol, in which the water in the mixture is predominant by weight in the aqueous or water-soluble plasticizer, and
wherein the thermomechanical kneading step and the adding step are part of a first kneading phase.
35 . The process according to claim 34 , wherein the proportion of the starch in the composition ranges from 15 to 40 phr.
36 . The process according to claim 34 , wherein the proportion of the aqueous or water-soluble plasticizer in the composition ranges from 7 to 28 phr.
37 . The process according to claim 34 , wherein the first kneading phase includes:
kneading all elastomers of the composition;
subsequently adding the starch and the aqueous or water-soluble plasticizer in one portion or in parts; and
adding other constituents of the rubber composition after the starch and the aqueous or water-soluble plasticizer are added.
38 . The process according to claim 34 , wherein the first kneading phase is carried out at a temperature of between 25° C. and 180° C.