# US 12,759,193 B2 · Method and device for producing recycled elastomer material to be crosslinked > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,759,193 B2 - Document ID: US12759193B2 - Status: Granted - Kind: B2 - Application number: 18/841,083 - Filed: 2023-02-27 - Published: 2025-06-05 - Granted: 2026-10-13 - Earliest claimed: 2022-02-25 - Assignees: Rubbergreen Industrie - Applicants: Rubbergreen Industrie - Inventors: Said Seghar; Olivier Prud'Homme - Web page: https://patentgrep.com/patent/US12759193B2 ## CPC - B29B 7/7495: {for mixing rubber} - B29B 7/007: {for continuous mixing} - B29B 7/487: {with consecutive casings or screws, e.g. for feeding, discharging, mixing} - B29B 7/82: Heating or cooling - B29B 7/88: Adding charges {, i.e. additives} - B29K 2021/00: Use of unspecified rubbers as moulding material - B29K 2105/0094: {having particular viscosity} - B29K 2105/246: {Uncured, e.g. green} - B29K 2105/26: Scrap {or recycled material} - B29B: PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS - B29K: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR {MOULDS, } REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS ## Abstract Method for producing rubbery material ready for crosslinking, comprising a continuous extrusion of crosslinked rubber, in grains and/or chips, comprising i) decrosslinking by mechanical shearing of said grains and/or chips and increasing the temperature until a decrosslinked paste is formed, ii) cooling said decrosslinked paste with the optional addition of at least one additive, and iii) mixing the cooled decrosslinked paste with at least one crosslinking agent, and collecting, at the end of this continuous extrusion, a pasty mixture forming said rubbery material ready for crosslinking. ## Claims ### Claim 1 A method for producing rubbery material ready for crosslinking, comprising extrusion of crosslinked rubber, in grains and/or chips, comprising: decrosslinking by mechanical shearing of said grains and/or chips of said crosslinked rubber and increasing the temperature until a decrosslinked paste is formed, cooling of the decrosslinked paste, and mixing of the cooled decrosslinked paste with at least one crosslinking agent, and collecting, at the end of this extrusion process, a pasty mixture forming said rubbery material ready for crosslinking, characterized in that: said extrusion is continuous, said decrosslinking step is carried out in a twin-screw type extruder, and said decrosslinked paste, obtained after the decrosslinking step, comprises a soluble fraction in an amount of between 10 and 35% by weight relative to the total weight of the decrosslinked paste. ### Claim 2 (depends on 1) The method according to claim 1, characterized in that said increase in temperature is generated by an input of external thermal energy and/or by self-heating of said grains and/or chips during said shearing. ### Claim 3 (depends on 1) The method according to claim 1, characterized in that said material ready for crosslinking has a crosslinking temperature, and in that said mixing of the cooled decrosslinked paste takes place at a temperature lower than this crosslinking temperature. ### Claim 4 (depends on 1) The method according to claim 1, characterized in that it comprises additional cooling via forced convection of said rubbery material during collection. ### Claim 5 (depends on 1) The method according to claim 1, characterized in that said continuous extrusion further comprises compounding of the decrosslinked material with at least one additive, during or after its cooling. ### Claim 6 (depends on 5) The method according to claim 5, characterized in that said at least one additive to be added during compounding is chosen from reinforcing fillers, diluting fillers, plasticisers, oils, antioxidants, anti-ozone protectors and mixtures thereof. ### Claim 7 (depends on 1) The method according to claim 1, characterized in that said at least one crosslinking agent is chosen from elastomer crosslinking agents, sulphur, peroxides, metal oxides, phenolic resins and mixtures thereof. ### Claim 8 (depends on 1) The method according to claim 1, characterized in that the paste ready for crosslinking has a Mooney viscosity of between 10-120 determined according to the ISO-289 standard. ### Claim 9 (depends on 8) The method according to claim 8, characterized in that the decrosslinking step is carried out at a temperature below 350° C. ### Claim 10 (depends on 9) The method according to claim 9, characterized in that the successive steps of decrosslinking, cooling and mixing take place in a twin-screw type extruder. ### Claim 11 (depends on 1) A device for producing rubbery material ready for crosslinking to implement the method according to claim 1, comprising a continuous extrusion device comprising an upstream inlet end provided with a system for supplying crosslinked rubber, in grains and/or chips, and a downstream end for collecting said rubbery material ready for crosslinking, and characterized in that the said device comprises, between these ends, successively a sector for decrosslinking said grains and/or chips coming from the supply system, where said crosslinked rubber is transformed into a decrosslinked paste, a cooling sector, where the decrosslinked paste is cooled and a mixing sector provided with said downstream end, wherein at least one dosing device is provided for introducing at least one crosslinking agent into the cooled decrosslinked paste and in that the said extrusion device is a twin-screw type extruder. ### Claim 12 (depends on 11) The device according to claim 11, characterized in that the continuous extrusion device is an extruder comprising the sectors of decrosslinking, cooling and mixing in linear succession between said upstream inlet end and said downstream collection end. ### Claim 13 (depends on 11) The device according to claim 11, characterized in that the continuous extrusion device comprises several successive extruders. ### Claim 14 (depends on 13) The device according to claim 13, characterized in that the continuous extrusion device comprises a first extruder, which comprises said upstream inlet end, said decrosslinking and cooling sectors in linear succession and an outlet for said cooled decrosslinked paste, and a second extruder, which comprises an inlet, into which said cooled decrosslinked paste is fed directly from the outlet of the first extruder, said mixing sector and said downstream collection end. ### Claim 15 (depends on 11) The device according to claim 11, characterized in that, in the cooling sector, at least one feeding device is provided for introducing, into the decrosslinked paste, at least one additive. ### Claim 16 (depends on 11) The device according to claim 11, characterized in that each of said sectors comprises a static barrel consisting of at least one barrel element and in each barrel element at least one screw driven rotationally by a motor. ### Claim 17 (depends on 11) The device according to claim 11, characterized in that said system for supplying crosslinked rubber, in grains and/or chips, is a gravimetric doser connected by a pipe to the upstream inlet end of the continuous extrusion device. ### Claim 18 (depends on 11) The device according to claim 11, characterized in that at least one barrel element of the decrosslinking sector is heated. ### Claim 19 (depends on 11) The device according to claim 11, further comprising, at said downstream end for collecting said rubbery material ready for crosslinking, a system for cooling via forced convection of this material.