EP-4735269-A1 - PROCESS FOR THE PRODUCTION OF HYDROCARBON RESINS FROM POLYSTYRENE RESIDUES AND TIRE RESIDUES

Abstract

The invention relates to a process for producing hydrocarbon resins from a feedstock of styrene compounds and a feedstock comprising rubber chips, to the resin produced by said process, and to a rubber composition comprising a resin of said kind.

Inventors

• LECOQ, Aurélie
• MAISONNEUVE, Lise
• SUTTER, MARC
• TOULEMONDE, Paul-Aymé

Assignees

• COMPAGNIE GENERALE DES ETABLISSEMENTS MICHELIN

Dates

Publication Date

20260506

Application Date

20240625

Claims (1)

1. CLAIMS [Claim 1] A process for producing hydrocarbon resins from a charge of styrenic compounds and a charge comprising rubber chips, said process comprising at least: a. A step of preparing the charge of styrenic compounds so as to be able to feed this charge into the pyrolysis step; b1. A step of pyrolysis of the charge of styrenic compounds making it possible to obtain at least one gaseous effluent and one pyrolysis oil, said gaseous effluent comprising at least 20% by weight of aromatic compounds; c1. A step of separating the gaseous effluent from step b1) into at least one stream rich in light compounds, one stream rich in aromatics and one stream rich in heavy compounds; b2. A step of pyrolysis of the feedstock comprising rubber chips carried out at a temperature of between 300 and 900°C with an increasing temperature ramp, making it possible to obtain a gaseous effluent, a pyrolysis oil and a solid effluent, said pyrolysis oil comprising at least 1.5% by weight of C4-C12 olefinic monomers; c2. A step of separation of the pyrolysis oil resulting from step b2) into at least one raffinate, an intermediate fraction and an extract, the intermediate fraction having a boiling point at atmospheric pressure of between 140 and 280°C and comprising at most 10% by weight of heteroatoms; d. A step of synthesis of resins comprising a polymerization section supplied at least by a flow resulting from step c1) and by the intermediate fraction resulting from step c2), followed by a finishing section and producing a polymerized effluent; e. A treatment step comprising a section for separating the polymerized effluent from step d) into a solvent-rich effluent and a resin-rich effluent, and a drying section fed with the resin-rich effluent in order to produce a stream of hydrocarbon resins. [Claim 2] A method according to the preceding claim, in which the charge of styrenic compounds is a charge of styrenic compounds from plastic waste comprising at least 90% by weight of polystyrene. [Claim 3] A method according to any one of the preceding claims, in which the rubber chips comprise at least 50 phr of diene elastomer, preferably at least 60 phr of diene elastomer. [Claim 4] A method according to any one of the preceding claims, in which the charge of styrenic compounds is gradually heated during step a) to a temperature of between 100°C and 300°C, preferably between 150°C and 300°C and more preferably between 200°C and 300°C. [Claim 5] Process according to any one of the preceding claims, in which the pyrolysis step b1) comprises a pyrolysis reactor operated at a temperature ranging from 300°C to 900°C and preferably ranging from 300 to 800°C and a pressure ranging from 0.8 bar to 7.5 bar. [Claim 6] Process according to any one of the preceding claims, in which the pyrolysis step b1) implements a microwave pyrolysis step. [Claim 7] Process according to any one of the preceding claims, in which the separation step c1) is implemented by distillation. [Claim 8] Process according to any one of the preceding claims, in which the mass ratio of the flow from step c1) to the intermediate fraction from step c2) feeding step d) is adjusted so that the resin obtained has a molar ratio of aliphatic H to aromatic H ranging from 40/60 to 95/5, preferably ranging from 50/50 to 90/10, more preferably ranging from 55/45 to 90/10. [Claim 9] Process according to any one of the preceding claims, in which the polymerization section of resin synthesis step d) is also fed with a solvent flow chosen from aliphatic, aromatic, halogenated solvents and mixtures thereof. [Claim 10] Process according to any one of claims 1 to 8, fed only with the feedstock of styrenic compounds and the feedstock comprising rubber chips, the solvent necessary in step d) being provided by at least one stream from step c2) and/or at least a fraction of the pyrolysis oil from step b1). [Claim 11] Process according to the preceding claim, in which at least a fraction of the pyrolysis oil from step b1) feeds step d) of resin synthesis. [Claim 12] Resin prepared by the process according to any one of the preceding claims having the following characteristics: ^ a glass transition temperature (denoted Tg) ranging from 20°C to 140°C; ^ a number-average molar mass of less than 5000 g/mol, preferably less than 4000 g/mol and preferably less than 3000 g/mol; ^ a dispersity Đ of less than 3, preferably less than 2.5 and preferably less than 2; ^ An aromatic proton content, determined by 1H NMR, of between 0.5 mol% and 50 mol%, preferably of between 2 mol% and 30 mol% and more preferably of between 2 mol% and 20 mol%; ^ An aliphatic proton content, determined by 1H NMR, of between 50 mol% and 99.5 mol%, preferably of between 70 mol% and 98 mol%, preferably of between 80 mol% and 98 mol%; ^ An ethylenic proton content, determined by 1H NMR, of less than or equal to 10 mol%, preferably less than or equal to 5 mol%, preferably less than or equal to 4 mol%, the sum of the aromatic, aliphatic and ethylenic proton content being equal to 100%. Preferably, the level of ethylenic protons, determined by 1H NMR, is greater than or equal to 0.5 mol%, preferably greater than or equal to 1 mol%. [Claim 13] Rubber composition based on at least one elastomeric matrix comprising at least 50 phr of a butadiene copolymer, a reinforcing filler, a crosslinking system and a hydrocarbon resin according to the preceding claim, or prepared by the process according to any one of claims 1 to 11. [Claim 14] Rubber composition according to the preceding claim in which the butadiene copolymer has a glass transition temperature Tg of less than -20 °C, preferably between -20 °C and -110 °C. [Claim 15] A vehicle tire, the tread of which comprises a rubber composition according to one of claims 13 or 14.

Description

Process for producing hydrocarbon resins from polystyrene residues and tire residues Technical field of the invention The present invention relates to the field of processes for producing hydrocarbon resins from recycled residues, to the resins produced by such processes and to the compositions comprising these resins, in particular the compositions intended for rubber articles and in particular vehicle tires. Prior art Tires, and more generally rubber articles such as for example conveyor belts and non-pneumatic tires, are complex objects made up of a multitude of components. For example, a tire is made up of more than 200 different raw materials, among which are different families of elastomers, reinforcing fillers, oils, hydrocarbon resins. Within hydrocarbon resins, hydrocarbon resins having a high glass transition temperature (Tg) comprising both aliphatic functions and aromatic functions are used to shift the performance compromises of the mixtures, such as rolling resistance or grip. These resins make it possible, in particular, to modify the Tg of the mixture. Such resins having a high Tg are known from the state of the art and described, for example, in documents WO2016/043851, US9139721 or FR2968006. The compatibility of the resins with the elastomeric matrix, and in particular their ability to disperse correctly in the mixture, is essential for them to play their role correctly. The compatibility of the resin with an elastomeric matrix depends, among other things, on properties such as the glass transition temperature and the softening point of the resin, these properties being dependent on the molar mass, the nature and the ratio of aromatic units to aliphatic units of the resin (see for example J. Appl Polym. Sci 2022139(15) 51950). It is therefore important to be able to vary these parameters in order to address the variety of elastomers used in rubber compositions. Such resins comprising aliphatic and aromatic units are well known in the state of the art, for example in document EP 0936229 which teaches the manufacture of hydrocarbon resins from aliphatic and aromatic monomers in cationic polymerization, from petroleum-based streams. While the performance of tires such as rolling resistance and wear resistance are key to limiting the environmental impact of these tires, it is also important to seek to limit as much as possible the use of fossil resources during the manufacture of rubber articles. Document US2013/0281611 describes a rubber composition for tires that includes a plasticizer from the recycling of waste, the plasticizer being used here as a substitute for process oils. Documents WO2022/101562 and WO2022/101563 describe the production of hydrocarbon resins from residues from the pyrolysis of rubber chips. However, these documents do not address the issue of adjusting the microstructure of the resins, and in particular adjusting the rate of aromatic and aliphatic monomers. Thus, an object of the present invention is to provide a method for producing resins that can be incorporated into a wide variety of elastomeric compositions from bio-sourced and/or recycled resources. Detailed description of the invention The invention relates to at least one method for producing hydrocarbon resins from a feedstock of styrenic compounds and a feedstock comprising rubber chips, said method comprising at least: a. A step of preparing the feedstock of styrenic compounds so as to be able to feed this feedstock into the pyrolysis step; b1. A step of pyrolyzing the feedstock of styrenic compounds to obtain at least one gaseous effluent and one pyrolysis oil, said gaseous effluent comprising at least 20% by weight of aromatic compounds; c1. A step of separating the gaseous effluent from step b1) into at least one stream rich in light compounds, one stream rich in aromatics and one stream rich in heavy compounds; b2. A step of pyrolysis of the feedstock comprising rubber chips carried out at a temperature of between 300 and 900°C with an increasing temperature ramp, making it possible to obtain a gaseous effluent, a pyrolysis oil and a solid effluent, said pyrolysis oil comprising at least 1.5% by weight of C4-C12 olefinic monomers; c2. A step of separation of the pyrolysis oil resulting from step b2) into at least one raffinate, an intermediate fraction and an extract, the intermediate fraction having a boiling point at atmospheric pressure of between 140 and 280°C and comprising at most 10% by weight of heteroatoms; d. A resin synthesis step comprising a polymerization section supplied at least by a stream from step c1) and by the intermediate fraction from step c2), followed by a finishing section and producing a polymerized effluent; e. A treatment step comprising a section for separating the polymerized effluent from step d) into a solvent-rich effluent and a resin-rich effluent, and a drying section supplied by the resin-rich effluent in order to produce a stream of hydrocarbon resins. Preferably