EP4669693A1

EP4669693A1 - MECHANOCHEMICAL UPCYCLING OF POLYMER WASTE

Info

Publication number: EP4669693A1
Application number: EP24708569.9A
Authority: EP
Inventors: Charles DIESENDRUCK; Sinai AHARONOVICH
Original assignee: Technion Research and Development Foundation Ltd
Current assignee: Technion Research and Development Foundation Ltd
Priority date: 2023-02-23
Filing date: 2024-02-19
Publication date: 2025-12-31
Also published as: WO2024176220A1

Abstract

The invention generally concerns a mechano-chemical process for upcycling or recycling of polymeric waste.

Description

MECHANO-CHEMICAL UPCYCLING OF POLYMER WASTE

TECHNOLOGICAL FIELD

The invention generally contemplates processes for upcycling polymer waste.

BACKGROUND OF THE INVENTION

Environmental concerns, marketing pressures and consumer demand have brought an increase in the demand for recycled plastic as opposed to virgin plastic derived from oil. Upcycling of plastic materials, namely the use of recycled plastic to create new plastic objects with improved properties and value, has seen little success as most of the plastic objects collected and recycled are deemed unsuitable for use. This is mainly due to the variability of the plastic objects which include different types of plastics, different non-plastic materials, and polymers with different molecular weights. Most polyolefin post-consumer recycled plastics are contaminated with other plastics such as polyethylene terephthalate, polyamide, glues; and even non-polymeric materials such as wood, paper, glass, metals etc, which drastically limit the possibilities of reuse as polymer properties are severely deteriorated.

EP Patent No. 0963825 discloses a process for grinding plastic materials in presence of carbon dioxide in a liquid state inside the grinding vessel capable of destructing the plastic materials and to ensure the compatibility of heterogeneous plastic materials in order to allow the recovery thereof from urban and industrial waste.

BACKGROUND PUBLICATIONS

[1] EP Patent No. 0963825

GENERAL DESCRIPTION

Disclosed herein is a mechano-chemical process for converting waste polymeric materials into reusable and upcycled polymeric products. The process of the invention not only permits an effective process that can be run at exceedingly low temperatures, but which also uniformly transforms a variety of polymers into block and grafted block copolymers of predictable compositions. Processes of the invention generally involve mechanical means which homogenize plastic waste by breaking the polymeric chains into segments of smaller molecular weights. Under the milling conditions, reactive groups formed due to bond cleavage (radical species and other unstable species) remain reactive sufficiently long to result in the reassembly of the segments into different block copolymers or grafted block copolymer of various compositions, which can act as compatibilizers between different polymers which did not recombine. A reduction in the observed viscosities alongside with a reduction in the size of impurity domains which may be present in the plastic waste, result in a surprising improvement in the mechanical properties of the polymers formed and any upcycled product formed therefrom.

In most general terms, a process of the invention involves mechanical grinding or mechanical bond scission that can be brought about by any other mechanical force, e.g., a crushing force, involving a high mechanical energy and a low temperature, applied onto polymeric materials, typically comprising post-consumer plastic materials. These materials, typically considered waste of industrial or municipal origin, may comprise polymer-based products or objects of any form, including multilayered polymeric materials and objects of mixed compositions. The mechanical forces, e.g., achieved by grinding, transform the waste material into a thermoplastic polymeric mass of block copolymers and other components as disclosed herein. The polymeric mass obtained may be in a particulate form, wherein the particles are of a size ranging between 20 and 1,000 microns. The polymeric mass may be used as a compatibilizer mass or as a raw material for manufacturing polymeric objects of unlimited form, size and utility.

Processes of the invention are mechano-chemical processes which involve application of mechanical forces to the waste polymeric material, under conditions which allow for bond scission of polymers present in the waste polymeric material, and in some cases, a subsequent bond formation. The use of mechanical energy activates, initiates or promotes the bond scission and reassembly reactions. As the mechanical energy may be applied in an absence of a solvent or a reactive material, the application of mechanical forces, e.g., impact forces or shear forces results in length-reduced polymeric chains or radical segments of predictable sizes (molecular weights) and predictable reassembly pathways that can reassemble into block copolymers and graft block copolymers. While the resulting product or polymeric mass is a material composition that is derived from the polymers present in the polymeric waste material, the mass is nevertheless different therefrom both in composition and properties.

The mechano-chemical process may involve application of any impact force and/or shear force. Such forces may be applied by means known in the art, for example by abrasive means. In some cases, the mechano-chemical process involves grinding.

Thus, in a first of its aspects, the invention provides a mechano-chemical process for recycling a polymeric waste material, the process comprising mechanically treating, e.g., by application of an abrasive forces such as grinding, the waste material under mechanical conditions sufficient to cause polymers in said waste material to undergo chain scission into size reduced polymeric materials and polymer chain reassembly into block copolymers and grafted block copolymer, wherein the mechanical conditions comprise application of high mechanical energy under low temperatures, in absence of carbon dioxide and optionally absence of a solvent.

Further provided is a mechano-chemical process for forming a polymer mass comprising a combination of block copolymers and size-reduced polymeric materials from a polymeric waste material being substantially free of block copolymers and grafted block copolymers, the process comprising mechanically treating, e.g., by grinding, the polymeric waste material under mechanical conditions sufficient to cause polymer chain scission and polymer chain reassembly to obtain the polymer mass comprising at least 1 wt% of block copolymers and length-reduced (or molecular weight reduced) polymeric materials.

In some embodiments, the polymer mass obtained from the mechano-chemical process may comprise block copolymers and/or grafted block copolymers in an amount of at least lwt%. In some embodiments, the amount of the block copolymers and/or grafted bock copolymers is between 1 and 100 wt%.

In some embodiments, the amount of the block copolymers and/or grafted bock copolymers in the polymeric mass obtained is between 1 and 100 wt%, or between 1 and 99 wt%, 1 and 95 wt%, 1 and 90 wt%, 1 and 85 wt%, 1 and 80 wt%, 1 and 75 wt%, 1 and 70 wt%, 1 and 65 wt%, 1 and 60 wt%, 1 and 55 wt%, 1 and 50 wt%, 1 and 45 wt%, 1 and 40 wt%, 1 and 35 wt%, 1 and 30 wt%, 1 and 25 wt%, 1 and 20 wt%, 1 and 10 wt%, 1 and 5 wt%, 5 and 100 wt%, 10 and 100 wt%, 20 and 100 wt%, 30 and 100 wt%, 40 and 100 wt%, or between 50 and 100 wt%. The invention further provides a process for upcycling a polymer waste material, the process comprising mechanically grinding the polymer waste material being substantially free of block copolymers and grafted block copolymers, under mechanical conditions sufficient to provide a thermoplastic mixture of block copolymers in a matrix formed of size-reduced polymeric materials having a particulate form and a size range between 20 and 1,000 microns.

Further provided is a process for converting a polymeric waste material comprising or essentially consisting at least one polyolefin into a polymeric mass comprising a polymeric composition different from a composition of the polymeric waste material, the process comprising mechanically treating, e.g., by grinding, the waste material under mechanical conditions sufficient to form the polymeric mass comprising or consisting length-reduced polyolefins and block copolymer and/or grafted block copolymer thereof, optionally as a particulate mass.

Processes of the invention do not involve use of liquid carbon dioxide, solvents, reactive agents, polymerizing materials, radical scavengers, radical initiators, or other reactive materials. In other words, the mechanical grinding may be carried out in the dry. The waste may be prewashed or pretreated in any way; however, the actual grinding is typically achieved when the waste is in a dry (water free) or a substantially dry state. In some cases, nevertheless, the waste material may be wet or grinding may require presence of small amounts of water or a solvent or a liquid additive. In such cases, the amount of water or solvent or a liquid additive may not exceed 10 wt%.

In some cases, the waste material is prewashed and/or pretreated to reduce the polymeric waste into smaller pieces or fragments which allow efficient grinding.

The mechanical equipment used for achieving polymer scission may be any mechanical equipment capable of abrasing, crushing and cutting the polymeric waste material. The mechanical equipment may be a grinding equipment known in the art. The grinding equipment may be selected based on its capability to produce sufficient collision forces between a solid body, a solid surface or grinding elements (such as metal balls) and the polymeric materials. The collision forces may be generated due to a rotational motion, gravitational motion, vibrational motion or any other motion of the grinding elements with respect to the polymeric materials. The grinding equipment may thus be selected amongst mills, hammers, crushers, pulverizes, kneaders, high shear dispersers, homogenizers and a variety of mixers. Non-limiting examples include ball or pebble mills, jet mills, hammer mills, rod mills, three-roll mills, ribbon mixers, double planetary mixers, and rotor stator mixers.

In some embodiments, the mechano-chemical process comprises mechanically grinding the waste material in a high-energy milling unit. The high-energy milling unit may be selected from a ball mill, a planetary mill, a vibration mill, an attritor (stirring ball mill), a pin mill, or a rolling mill unit, as known in the art.

In some embodiments, mechanical grinding is achievable by ball milling in a ball mill unit as known in the art. The type of ball milling equipment used may vary and may depend on the volume of material to be mechanically treated, the conditions of operation, and other factors as known to a practitioner in the field. To achieve sufficient impact and attrition forces, horizontal ball milling, vibrational ball milling, vertical ball milling, industrial ball milling, and planetary ball milling, just to name a few, may be utilized.

In some embodiments, the mechano-chemical process comprises mechanically grinding the waste material in an extruder.

The mechanical conditions sufficient to form the polymeric mass typically involve application of high mechanical energy and low temperatures. The term “high mechanical energy encompasses contacting of the polymeric waste with a mechanical force that is high enough to cause energetic collisions that induce high-speed plastic deformations, mechanical grinding, covalent bond scission in polymeric chains, reduction of the polymeric chain lengths, welding or reconnection into the copolymers, and efficient mixing. Shear forces are applied as milling is continued for prolonged periods of time, lasting between several minutes or several hours to several days.

The high energy may be achievable by using ball milling, in which case the term is interchangeable with “energetic ball milling

In a process of the invention, the polymeric materials contained in the polymeric waste may vary and may include polymers of any composition and polymer type. The polymeric waste may be or may comprise post-industrial and/or post-consumer polymeric waste, comprising any polymeric object recovered from within an industrial setting or from consumer plastic waste, and which does not comprise block copolymers or size reduced polymeric materials present in the polymeric mass obtained after the mechano-chemical processing. Even if present, such material undergoes the same mechano-chemical conditions to yield yet different products. The polymeric waste is said to be “substantially free " of block copolymers and/or grafted block copolymers. In other words, while the polymeric waste may comprise any industrial or consumer product, which may include random copolymers and other additives of a variety of forms and compositions, the amount of any block copolymer and/or grafted block copolymer may be insignificant, may be small, or may be in an amount that is below 10wt%. In some cases, if present, the amount of block copolymers and/or grafted block copolymers in the polymeric waste may be between 0.02 and 10wt% or between 0.02 and 5wt%.

In some cases, the polymeric waste may comprise random copolymers and is free or substantially free of block copolymers. In some embodiments, the amount of random copolymers in the waste material is below 5 wt% or between 0.02 and 5wt% or between 0 and 5wt%.

In some embodiments, the waste material comprises one or more polymers of the polyolefin family, and optionally one or more polymer(s) that is/are not a polyolefin.

The polymeric waste material used in a process of the invention may contain any amount of a polyolefin, which may be of any molecular weight, and any composition. The amount of the polyolefin in the waste material may vary between 50 wt% and 100 wt%. In some embodiments, the amount of the polyolefin is between 50 and 90 wt%, 50 and 85 wt%, 50 and 80 wt%, 50 and 75 wt%, 60 and 99 wt%, 60 and 90 wt%, 60 and 85 wt%, 60 and 80 wt%, 60 and 75 wt%, 70 and 99 wt%, 70 and 90 wt%, 70 and 85 wt%, 70 and 80 wt%, 80 and 99 wt%, 80 and 90 wt%, or between 90 and 99 wt%, relative to the total amount of the waste material used in a process of the invention.

The polymeric waste material may comprise, in addition to the polyolefin or a mixture of polyolefins, a variety of other materials which may be processed along with the polyolefin materials. The additional materials are non-olefinic materials, which may constitute between 1 and 50 wt% of the polymeric waste material used. The additional materials may be polymeric materials other than polyolefins, including natural polymers (such as cellulose and natural rubber); synthetic polymers (such as thermoplastics, thermosets, elastomers, and synthetic fibers e.g., neoprene, Nylon, rayon, Teflon, epoxy resins, silicone and others); polyesters such as polyethylene terephthalate (PET), poly(butylene terephthalate) (PBT), poly(hexamethylene terephthalate) (PHT), poly(propylene terephthalate) (PTT); semi- synthetic polymers; adhesives; pigments and dyes; stabilizing materials such as heat and light stabilizers, antioxidants, flame retardants, defoamers, anticoagulants, salts, processing agents, modifiers and others.

The polyolefin may be a single material or a combination of materials, wherein the amount of the material or combination of materials is between 50 and 99 wt%, as disclosed herein. Where a combination of polyolefins is concerned, the relative amounts of the different polyolefins may differ and have no real effect on the process herein. However, in some embodiments, the amount of polyethylene should be at least 50% of the total amount of the polyolefin used.

In some embodiments, the polyolefin may be selected from polyethylene, polypropylene, and/or random copolymers thereof. Such polyolefins may be selected from high-density and high-molecular-weight polyethylene, high-density polyethylene (HDPE), linear-low-density polyethylene (LLDPE), low-density polyethylene (LDPE) and polypropylene.

In some embodiments, the polyolefin is or comprises a polyethylene selected from high-molecular-weight polyethylene, high-density polyethylene (HDPE), linear- low-density polyethylene (LLDPE), and low-density polyethylene (LDPE).

In some embodiments, the polymeric waste material comprises or consists a high-molecular-weight polyethylene and/or high-density polyethylene (HDPE) and/or linear- low-density polyethylene (LLDPE) and/or low-density polyethylene (LDPE), optionally in combination with polyethylene terephthalate (PET).

In some embodiments, the polymeric waste material comprises or consists high- molecular-weight polyethylene or high-density polyethylene (HDPE) or linear-low- density polyethylene (LLDPE) or low-density polyethylene (LDPE); and polyethylene terephthalate (PET).

In some embodiments, the polymeric waste material comprises or consists a combination of polyethylene and polypropylene, wherein the polyethylene may be one or more of polyethylene terephthalate (PET), high-density polyethylene (HDPE), linear- low-density polyethylene (LLDPE), low-density polyethylene (LDPE).

In some embodiments, the polymeric waste material comprises or consists polyethylene and/or polypropylene, optionally in combination with PET.

In some embodiments, in a mechano-chemical process of the invention, for forming a block copolymer from a polymeric waste material, the polymeric waste material may comprise: -at least one polyolefin selected from high-density and high-molecular-weight polyethylene, high-density polyethylene (HDPE), linear- low-density polyethylene (LLDPE), low-density polyethylene (LDPE) and polypropylene;

-at least one polyolefin selected from high-molecular- weight polyethylene, high- density polyethylene (HDPE), linear- low-density polyethylene (LLDPE), and low- density polyethylene (LDPE);

-at least one polyolefin that is or comprises high-molecular-weight polyethylene and/or high-density polyethylene (HDPE) and/or linear-low-density polyethylene (LLDPE) and/or low-density polyethylene (LDPE);

-at least one polyolefin that is or comprises high-molecular-weight polyethylene or high-density polyethylene (HDPE) or linear-low-density polyethylene (LLDPE) or low-density polyethylene (LDPE);

-polyethylene terephthalate (PET) and at least one polyolefin, e.g., PE and/or PP;

-polyethylene and PET;

-polyethylene and polypropylene.

As known in the art, high-density polyethylene (HDPE) is a polyethylene thermoplastic having a mass density between 0.93 to 0.97 gr/cm³. Low-density polyethylene (LDPE) are branched homopolymers having densities ranging between 0.915 to 0.930 g/cm³. LDPE typically contains long branches off the main backbone with alkyl substituents of two to eight carbon atoms. Linear low-density polyethylene (LLDPE is a copolymer of ethylene and a minor amount of an olefin containing 4 to 10 carbon atoms. LLDPE may have a density ranging from 0.910 to 0.930 gr/cm³.

In some embodiment, the waste material is an industrial waste, a municipal waste or waste of any other source which comprises or essentially consists of polymeric objects or polymeric materials made from PP, PE, PE/PET mixture, or any other mixture thereof. In some cases, at least 50 wt%, or at least 55, 60, 65, 70, 75, 80, 85, 90, 95 or 100wt% of the waste is made of PP, PE, PE/PET mixture or any other mixtures thereof.

In some embodiments, the amount of PP or PE in a mixture, e.g., where a combination of polyolefins is used, is between 50 and 100 wt% of the total amount of polyolefins in the polymer waste used. In some embodiments, the amount of the PE or PP is between 50 and 85 wt%, 50 and 80 wt%, 50 and 75 wt%, 50 and 70 wt%, 50 and 65 wt%, 50 and 60 wt%, 60 and 90 wt%, 65 and 90 wt%, or 70 and 90 wt%, 80 and 90 wt%.

The amount of the polyolefin and optionally the additional material in the waste used in a process of the invention may vary depending on the source and type of the polymeric material or waste used. Generally speaking, any plastic or polymeric material comprising a polyolefin is suitable as a raw material for upcycling. The waste material, either from a post-industry or a post-consumer waste, may be any solid or rigid object, including packaging materials, bottles, drums, plastic cans, cartridges, containers, caps, lids, plastic covers, trays, pouches, plastic chairs and tables, plastic utensils, cups, plates, bags, fishing nets, straws, stirrers, diapers, and many others.

As stated herein, processes of the invention are mechano -chemical processes which enable formation of block copolymers and/or grafted block copolymers from polymeric waste materials, as defined herein. Prior to mechanically grinding the waste material the waste material may be pre-treated. Pre-treatment may comprise one or more of:

-homogenizing the waste material,

-washing of the waste material to remove dirt, glass, water soluble materials, organic solvent materials, organic liquids or materials that may be associated or provided with the waste material,

-separating metallic objects,

-shredding or reducing in size the waste material, e.g., to a size of between several millimeters to few centimeters, or to any other size so that the subsequent grinding via, e.g., ball milling, is more efficient,

-washing out of paper and glass;

-density based separation;

-classification of polymeric materials; and

-others.

In some embodiments, the process comprises:

-obtaining a waste material comprising plastic or an olefinic material,

-pre-treating the waste material by one or more of washing the waste material, separating metallic objects, and/or shredding or reducing in size the waste material;

-mechanically grinding the pre-treated waste material under high energy, low temperature mechanical conditions sufficient to provide a thermoplastic block copolymer material particulate mass comprising particles of a size range between 20 and 1000 microns.

In some embodiments of any of the processes herein, the mechanical grinding is achievable as disclosed herein, e.g., by ball milling, under low temperature conditions, namely under a temperature between -200°C and 80°C. Thus, the “Zow temperature conditions employed include mechanical griding at a temperature between -200 and 80°C, -150 and 80°C, -100 and 80°C, -90 and 80°C, -80 and 80°C, -70 and 80°C, -60 and 80°C, -50 and 80°C, -40 and 80°C, -30 and 80°C, -20 and 80°C, -10 and 80°C, 0 and 80°C, 10 and 80°C, 20 and 80°C, 25 and 80°C, 30 and 80°C, 35 and 80°C, 40 and 80°C, 45 and 80°C, 50 and 80°C, 55 and 80°C, 60 and 80°C, 65 and 80°C, or between 70 and 80°C. The thermal conditions utilized in processes of the invention do not typically bring about melting of the polymeric mass. In other words, the temperature used may be selected to be lower than a melting temperature of any polymeric component present in the polymeric waste.

In some embodiments, the temperature is between room temperature (rt, 25- 30°C) and 80°C. In some embodiments, the temperature is below room temperature. In some embodiments, the temperature is above room temperature.

In some embodiments, the temperature is a temperature of liquid nitrogen or that of liquid CO2.

In some embodiments, the process of the invention comprising mechanically grinding in a ball mill the waste material at a temperature between -200°C and 80°C to cause polymers in said waste material to undergo chain degradation or chain scission to obtain size reduced polymeric materials and block copolymers and/or grafted block copolymer.

In some embodiments, the process comprising mechanically grinding in a ball mill waste material comprising at least one polyolefin at a temperature between -200°C and 80°C to cause the polyolefin to undergo chain degradation or chain scission to obtain polyolefins of reduced molecular weights and/or block copolymers of said polyolefin and/or grafted block copolymer of said polyolefin.

In some embodiments, the at least one polyolefin is PP and PE provided in combination with PET, to obtain a polymeric mass comprising or consisting one of more of a size reduced PP, a size reduced PE, a size reduced PET, a block copolymer of PP and PE, a grafted block copolymer of PP and PE, a block copolymer of PP and PET, a block copolymer of PE and PET, a grafted block copolymer of PP and PET and/or a grafted block copolymer of PE and PET.

The mechanical conditions used in the milling process decrease the size of the polymer waste dramatically, affording a final product that may be characterized as a mixture of low molecular weight polymers (size reduced polymers), block copolymer, and/or grafted block copolymers, each of which formed from recombination of length- reduced or molecular weight-reduced polymers originating from polymers in the polymeric waste, e.g., originating from length-reduced PP, PE, PET or mixtures thereof. The final product may be characterized by size-exclusion chromatography, and 2D- NMR.

As a person of skill would know, the reduction in the size or molecular weight or length of the original polymer present in the polymeric waste material may be caused by bond breaking or bond scission. The bond which breaks may be any covalent bond such as C-C, C-O, C-N and others. Bond scission may occur at any position along the polymeric chain and thus may yield polymer fragments of a variety of lengths. The fragments length or molecular weight may be between 10 and 90% (length, number of monomer or molecular weight) of the original polymer length or molecular weight. The reaction may be terminated depending on the composition of the polymeric waste by yielding polymer fragments (the so-called size reduced polymers) having a length or a molecular weight that is between 10 and 90% of the original length or molecular weight of the polymer, as well as block copolymers and grafted block copolymers. The “block copolymer” may comprise two or more of such segments that are chemically distinct regions or segments or blocks, each derived from a different polymer (e.g., one derived from PP and another from PE) that are joined in a linear manner via covalent bonds, in an end-to-end fashion. The block copolymers may be formed alternatively or additionally in a pendent or a grafted fashion to provide the “grafted block copolymer”, wherein one segment derived from one polymer is grafted onto a segment derived from a different polymer.

In some cases, the block copolymer may be a diblock or a triblock.

As stated herein, while the polymeric mass product is different in composition and properties from the original waste material, the structure of polymers contained in or making up the polymeric mass is derived from the type of polymers present in the waste material. For example, a size reduced PP may be derived from PP of a higher molecular weight. A block copolymer of PP and PET may be formed from PP and PET fragments formed under the conditions of the process. Thus, the final product may thus be characterized as a thermoplastic material, optionally formed as a particulate material. The final product may comprise one or a mixture of:

-block copolymer

-block copolymer of PP and PET (. ..-PP-PET-PP-PET...),

-block copolymer

-grafted block copolymer of PE and PET,

-grafted block copolymer of PP and PET,

-grafted block copolymer of PP and PE,

-size reduced PP (shorter chain, lower molecular weight PP), wherein the reduction in size (or molecular weight) is a reduction by at least 20, 30, 40 or 50%,

-size reduced PE (shorter chain, lower molecular weight PE), wherein the reduction in size (or molecular weight) is a reduction by at least 20, 30, 40 or 50%,

-size reduced PET (shorter chain, lower molecular weight PE), wherein the reduction in size (or molecular weight) is a reduction by at least 20, 30, 40 or 50%,

-size reduced forms of other plastic impurities in the waste, e.g., block copolymers and random copolymer, wherein the reduction in size (or molecular weight) is a reduction by at least 20, 30, 40 or 50%.

In some embodiments, the final product comprises a mixture of:

-block copolymer of PE and PET (. . -PE-PET-PE-PET-. . .), and

-size reduced PE (shorter chain, lower molecular weight PE), wherein the reduction in size (or molecular weight) is a reduction by at least 20, 30, 40 or 50%, and/or

-size reduced PET (shorter chain, lower molecular weight PE), wherein the reduction in size (or molecular weight) is a reduction by at least 20, 30, 40 or 50%.

In some embodiments, the final product comprises a mixture of:

-block copolymer of PP and PET (. ..-PP-PET-PP-PET...),

-size reduced PP (shorter chain, lower molecular weight PP), wherein the reduction in size (or molecular weight) is a reduction by at least 20, 30, 40 or 50%, and/or

-size reduced PET (shorter chain, lower molecular weight PE), wherein the reduction in size (or molecular weight) is a reduction by at least 20, 30, 40 or 50%. In some embodiments, the final product comprises a mixture of:

-block copolymer

-size reduced PE (shorter chain, lower molecular weight PE), wherein the reduction in size (or molecular weight) is a reduction by at least 20, 30, 40 or 50%.

In some embodiments, the final product comprises a mixture of:

-block copolymer of PE and PET (. . -PE-PET-PE-PET-. . .), and/or

-grafted block copolymer of PE and PET,

In some embodiments, the final product comprises a mixture of:

-block copolymer of PP and PET (. . -PP-PET-PP-PET. . .), and/or

-grafted block copolymer of PP and PET,

In some embodiments, the final product comprises a mixture of:

-block copolymer of PP and PE (. .. -PP-PE-PP-PE. . .), and/or

-grafted block copolymer of PP and PE,

In some embodiments, each of the products provided from processes of the invention may further comprise size reduced forms of other plastic impurities in the waste, e.g., block copolymers and random copolymer, wherein the reduction in size (or molecular weight) is a reduction by at least 20, 30, 40 or 50%.

In some embodiments, the product mixture comprises between 1 and 10 wt% of the block copolymers, with the remaining amount being a variety of size-reduced polymers, as disclosed above.

The final product is typically provided as a particulate matter having particles of a size ranging between 20 and 1,000 microns. The size of the particles may be characterized by DLS or by sieving. The particles may be used as a compatibilizer mass or as a recycling material for manufacturing of polymeric objects in combination with or in absence of virgin polymers. As a compatibilizer, the particle mass obtained may be added to a mixture of incompatible polymers, mixtures of virgin and recycled plastics, or polymer/fillers to suppress their phase separation by promoting an interaction between the components of the mixture.

Alternatively, the product of the invention may be used as a raw material in a process of injection molding or blow molding.

The invention thus provides:

A mechano-chemical process for recycling a polymeric waste material, the process comprising mechanically grinding the waste material under mechanical conditions sufficient to cause polymers in said waste material to undergo chain scission into size reduced polymeric materials and polymer chain reassembly into block copolymers and grafted block copolymer, wherein the mechanical conditions comprise application of high mechanical energy under low temperatures, in absence of carbon dioxide and optionally absence of a solvent.

In some configurations of any process of the invention, the polymeric waste material is free of or is substantially free of block copolymers and grafted block copolymers.

In some configurations of any process of the invention, the process is to obtain a polymeric mass comprising or consisting the size reduced polymeric materials, the block copolymers and/or the grafted block copolymer in a form of particles of a size range between 20 and 1,000 microns.

In some configurations of any process of the invention, the polymeric mass is a thermoplastic polymeric mixture. In some configurations of any process of the invention, the waste material is or comprises post-industrial polymeric products or objects or post-consumer polymeric products or objects.

In some configurations of any process of the invention, the waste material contains at least one polyolefin.

In some configurations of any process of the invention, the waste material contains a polyolefin selected from polyethylene, polypropylene, and/or copolymers thereof.

In some configurations of any process of the invention, the amount of the at least one polyolefin is between 50 and 100wt%.

In some configurations of any process of the invention, the polyolefin is selected from high-density and high-molecular-weight polyethylene, high-density polyethylene (HDPE), linear-low-density polyethylene (LLDPE), low-density polyethylene (LDPE) and polypropylene.

In some configurations of any process of the invention, the waste material comprises a polyolefin being or comprising high-molecular-weight polyethylene and/or high-density polyethylene (HDPE) and/or linear-low-density polyethylene (LLDPE) and/or low-density polyethylene (LDPE) in combination with polyethylene terephthalate (PET).

In some configurations of any process of the invention, the polyolefin is PE, PP or mixtures thereof.

In some configurations of any process of the invention, the polymeric waste material comprises PP and/or PE, and one or more other polymeric materials.

In some configurations of any process of the invention, the polymeric waste material comprises PP and/or PE and polyethylene terephthalate (PET).

In some configurations of any process of the invention, the polymeric waste material comprises or consists:

-at least one polyolefin selected from high-density and high-molecular-weight polyethylene, high-density polyethylene (HDPE), linear- low-density polyethylene (LLDPE), low-density polyethylene (LDPE) and polypropylene;

-at least one polyolefin selected from high-molecular- weight polyethylene, high- density polyethylene (HDPE), linear- low-density polyethylene (LLDPE), and low- density polyethylene (LDPE); -at least one polyolefin being or comprising high-molecular- weight polyethylene and/or high-density polyethylene (HDPE) and/or linear-low-density polyethylene (LLDPE) and/or low-density polyethylene (LDPE);

-at least one polyolefin being or comprising high-molecular- weight polyethylene or high-density polyethylene (HDPE) or linear-low-density polyethylene (LLDPE) or low-density polyethylene (LDPE);

-polyethylene terephthalate (PET) and at least one polyolefin;

-polyethylene and PET; or

-polyethylene and polypropylene.

In some configurations of any process of the invention, the mechanical grinding is achievable in a ball or pebble mill, jet mill, hammer mill, rod mill, three-roll mill, extruder, crusher, pulverizer, kneader, high shear disperser, homogenizer, ribbon mixer, double planetary mixer, or rotor stator mixer.

In some configurations of any process of the invention, the mechanical grinding is achievable by ball milling.

In some configurations of any process of the invention, the low temperature is a temperature below the melting temperature of the polymeric waste.

In some configurations of any process of the invention, the low temperature is between -200°C (200 degrees below zero°C) and 80°C.

In some configurations of any process of the invention, the low temperature is between 0 and 80°C.

In some configurations of any process of the invention, the process comprising mechanically grinding in a ball mill the waste material at a temperature between -200°C and 80°C to cause polymers in said waste material to undergo chain scission to obtain size reduced polymeric materials and/or block copolymers and/or grafted block copolymer.

In some configurations of any process of the invention, the process comprising mechanically grinding in a ball mill the waste material comprising at least one polyolefin at a temperature between -200°C and 80°C to cause the polyolefin to undergo chain scission to obtain polyolefins of reduced molecular weights and/or block copolymers of said polyolefin and/or grafted block copolymer of said polyolefin.

In some configurations of any process of the invention, the at least one polyolefin is PP and PE provided in combination with PET, to obtain a polymeric mass comprising or consisting one of more of a size reduced PP, a size reduced PE, a size reduced PET, a block copolymer of PP and PE, a grafted block copolymer of PP and PE, a block copolymer of PP and PET, a block copolymer of PE and PET, a grafted block copolymer of PP and PET and/or a grafted block copolymer of PE and PET.

In some configurations of any process of the invention, the process comprises obtaining the waste material.

In some configurations of any process of the invention, the process comprises pretreating the waste material by one or more of washing the waste material, separating metallic objects, and/or shredding or reducing in size the waste material.

In some configurations of any process of the invention, the process comprises:

-obtaining a waste material comprising plastic or an olefinic material,

-optionally pre-treating the waste material by one or more of washing the waste material, separating metallic objects, and/or shredding or reducing in size the waste material;

-mechanically grinding the waste material under conditions of high mechanical energy and a low temperature to provide a thermoplastic polymeric mass comprising or consisting a block copolymer material, a grafted block copolymer material and/or a size reduced polymeric material, in a form of particles of a size between 20 and 1000 microns.

Also provided is a polymeric mass formed according to the process.

In some configurations of a product of the invention, the polymeric mass is in a form of thermoplastic particles.

In some configurations of a product of the invention, the polymeric mass is for use as a compatibilizer.

In some configurations of a product of the invention, the polymeric mass comprises one or more of size-reduced polymers having a molecular weight or a length shorter than the corresponding polymers in the waste material, block copolymers formed from the size -reduced polymers and grafted block copolymers formed from the size reduced polymers.

In some configurations of a product of the invention, the polymeric mass comprising one or a mixture of:

-block copolymer of PE and PET,

-block copolymer of PP and PET, -block copolymer of PP and PE,

-grafted block copolymer of PE and PET,

-grafted block copolymer of PP and PET,

-grafted block copolymer of PP and PE,

-size reduced PP, wherein the reduction in size is a reduction by at least 20, 30, 40 or 50%,

-size reduced PE, wherein the reduction in size is a reduction by at least 20, 30, 40 or 50%,

-size reduced PET, wherein the reduction in size is a reduction by at least 20, 30, 40 or 50%.

In some configurations of a product of the invention, the polymeric mass comprising a mixture of:

-block copolymer of PE and PET, and

-size reduced PE, wherein the reduction in size is a reduction by at least 20, 30, 40 or 50%, and/or

-block copolymer of PP and PET,

-size reduced PP, wherein the reduction in size is a reduction by at least 20, 30,

40 or 50%, and/or

-block copolymer of PP and PE,

40 or 50%, and/or

-size reduced PE, wherein the reduction in size is a reduction by at least 20, 30, 40 or 50%.

In some configurations of a product of the invention, the polymeric mass comprising a mixture of: -block copolymer of PE and PET ; and/or

-grafted block copolymer of PE and PET,

-size reduced PE, wherein the reduction in size is a reduction by at least 20, 30,

40 or 50%, and/or

-block copolymer of PP and PET, and/or

-grafted block copolymer of PP and PET,

40 or 50%, and/or

-block copolymer of PP and PE, and/or

-grafted block copolymer of PP and PE,

40 or 50%, and/or

In some configurations of a process and a product of the invention, the method is for recycling the waste polymeric material into a thermoplastic polymeric mass having a different composition of matter, wherein the polymeric mass is as defined herein.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to better understand the subject matter that is disclosed herein and to exemplify how it may be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which:

Fig. 1 : PET incorporation in PE as a function of milling time in high energy ball milling. Fig. 2: COSY 2D-NMR showing covalent bonding between PET and PE after high energy ball milling in a linear fashion.

Fig. 3 : LDPE Dog-bones prepared according to ASTM D638 including upcycled PE-PET (from high energy ball milling multilayered waste) and recycled (>85% LDPE) and virgin LDPE.

Figs. 4A-C: Summary of mechanical properties in elastic region of samples from Fig. 3. Fig. 4A-Tensile strength; Fig. 4B- Stiffness; and Fig. 4C- Young’s Modulus.

Figs. 5A-C: Summary of mechanical properties in plastic region of samples from Fig. 3. Fig. 5A-Load at break; Fig. 5B- Strain at break; and Fig. 5C- Toughness.

Fig. 6: Schematic description of a process according to some embodiments of the invention: colored, multilayered PE/PET, was shredded and milled, washed with HFIP to remove unreacted PET, and provided as a powder to be used in the blowmolding pilot.

Fig. 7: Blow extrusion. Compositions and mechanical testing of the obtained films.

Fig. 8 : MFRs of milled big bags, with different particle sizes.

DETAILED DESCRIPTION OF EMBODIMENTS

The following discussion and Examples are mainly focused on upcycling postconsumer polymeric waste comprising polyethylene (PE) and polyethylene terephthalate (PET) and/or polypropylene (PP), or upcycling of waste comprising PP, potentially with impurities such as glue, polyethylene (PE), polyurethane, polyamide, EVOH.

General Process: polymer wastes composed of >70% of PE or PP were washed and shredded. Subsequently, a high energy milling process was used to induce a reduction in the lengths of the polymeric chains and recombine part of the shorter polymeric chains to form block copolymers. Finally, the mixture of block copolymer was used as a compatibilizer for more waste material, or as an improved source of recycled material. Example 1

A Vortex-based high energy ball mill having an internal volume of ca. 20 mL, out of which 1/3 was filled with material, 1/3 with spheres and the rest left open for efficient milling. The container and spheres were made of stainless steel (SL-316), spheres of size 3/16.

A material consisting of ca. 9 g PE and 1 g PET were first compounded and extruded. A 5g sample was milled for different times. A few mL of liquid N2 were added to the flask, which was then closed, providing a positive pressure of N2 in the flask.

To study how much PET remained, the material and the spheres were taken out and washed with hexafluoroisopropanol (HFIP), a solvent that dissolves PET rapidly, but not the copolymer or PE. The HFIP was collected and evaporated to provide the quantity of unreacted PET. The remaining solid was dried and weighted to provide the quantity of unreacted PE + PE/PET copolymer. This material could be washed with chloroform at room temperature, which was collected and evaporated, to provide a sample of the pure copolymer , which could be analyzed by NMR.

As seen in Fig. 1, a fast reaction occurs at the beginning, but the conversion rate decayed with time.

Example 2

Similar to Example 1 but using PP/PET mixture (9:1). In this case, results were improved compared to PE, reaching 49% PET incorporation into copolymers after 3.5 h of milling.

Example 3

Same as Examples 1 and 2, but instead of adding liquid N2, the atmosphere of air was exchanged directly to N2 using vacuum and nitrogen backfilling. In this case, incorporation of PET into copolymers reached 40% for milling with PE, and 60% for milling with PP, both after 3.5h milling.

Example 4. Characterization of block copolymer

Using the material from Example 1, the material coming from HFIP wash could be analyzed at room temperature by regular 'H-NMR in tetrachloroethane-d2. The block copolymer contained quite large amounts of PET ca. 12% (18% in PP). The PE/copolymer mixture was analyzed by high temperature NMR in tetrachloroethane -d2 to provide a more realistic quantification of the block copolymer - it was found to be ca. 5.5% in the case of PE/PET, and 10% in the case of PP/PET. A weighted internal standard (p-dimethoxybenzene) was used, and both relaxation times of the standard and polymers were measured.

2D NMR experiments (H-H correlation) were used to study how the PET and PE are connected to each other, as a graft on or as linear copolymer. As seen in Fig. 2, there is a clear peak connecting the PET methylene to a PE methylene (and not to a methine C-H, like seen in PP), indicating the copolymer is linear (i.e., block/multi block) and not grafted on.

Example 5

Similar to Example 1, but using a planetary mill (Pulverisette 6, Fritsch) with an internal volume of 300 mL. Both stainless steel and zirconia media were tested, however, in both cases, even after 12h milling, no mechanochemistry was obtained, i.e., most of the PET was completely recovered upon HFIP wash.

Example 6

Like Example 1, but using a CryoMill by Retsch. The polymer mixture was milled for 3 cycles of milling for 10 mins while cooling with liq. N2, and ca. 20% PET was incorporated into the PE.

Example 7

Like Example 6, but cooling is used only prior to milling. In this case, ca. 33% PET incorporation was achieved in 1.5h milling.

Example 8

Use of material from Example 7 (PE/PET) as a compatibilizer. Pure LDPE (PE 111, Carmel Olefins) and recycled PE (M21436 A, Shahaf, >90% PE) without any additives were compounded together with 1% compatibilizer. Compounding was done at a 10 g scale, at 200 C for 10 min, inverse twin screw at 35 rpm, Max torque 40 Nm. The extruded materials were cut into smaller pieces and hot pressed (140-150C) into a dogbone stainless steel mold, with a Teflon film to allow for easy release. The sizes and procedures for mechanical testing were taken from ASTM D638 type 4 (Fig. 3). Mechanical testing was done using a Lloyd TAI with a 500N cell at a strain rate of 50 mm/min. Results for elastic region are an average of all samples tested, but samples which failed early due to production failure were not considered in the plastic region. In addition to our own material (Example 1, "Technion”), different commercial additives were added also at 1% for comparison: AddWorks PKG 906 (Clariant) and Bondyram 4108 (Polyram).

All the samples of pure PE (pure - directly pressed into sample; processed - passed the compounding process without any additives), and all the samples with recycled material were repeated 5 times from different preparations. Results with error bars are an average of at least 4 samples for elastic region and at least 3 for plastic region. From the pure PE samples, it is clear that while results are slightly different, none are statistically significant i.e. the additive does not affect the properties of pure PE (Figs. 4A-C and 5A-C). However, when the material includes recycled material, some improvement on elastic region is seen, but it is not statistically significant (Figs. 4 and 5). On plastic region, however, significant improvement is seen (Figs. 4 and 5). The simple mixture of PE with recycled material (40 or 80%) fails quite early due to the presence of weak interfaces. The additives (commercial and ours) improve the interface binding, leading to better performance. Significant stretchability is seen with 40% and 80% with our additive, providing results which seem better than pure PE, but are statistically similar; i.e., our additive improves the mechanical properties of recycled PE by several times, making them comparable to virgin PE. Interestingly, the additive outperformed the commercial ones tested here.

Example 9

Similar to Example 1, but using a planetary mill (5 L volume), a hammer mill (5 L volume), and an attrition mill (IL). No mechanochemistry was observed - the PE did not chemically connect to the PET (by NMR).

Example 10

Similar to Example 1, but using a 50 L rotatory ball mill made of alumina, with a mixture of 4 and 2 cm diameter spheres.

In this case, batches of ca. 8 kg of plastic could be used (70% PE, 30% PET). Contrary to Example 1, the material was not pre-compounded. The multi-layered material was added directly after simple shredding. The mill worked in cycles of mill and rest, and each milling took three days. At the beginning, together with the plastic, the atmosphere was exchanged for CO2. As the process went, the material was filtered through a mesh (3 times a day), when all the powder was put aside as "milled product", and the larger particles returned to the mill for more milling (again, CO2 was used to replace the atmosphere). Example 11

Same as Example 10, but using PP (85%) and PE (15%), coming from compounded big-bags.

Example 12

Two laminated PE/PET multilayered materials were tested separately in this Example - white and colored. Both materials (70% PE/30% PET), were initially shredded and milled as described in Example 10 (Fig. 6).

DSC analysis was used and showed the presence of crystalline PET in the powder and therefore, the material was washed with HFIP. The washing was done using a round-bottomed flask, in which the powder was dispersed in HFIP, and after mixing with a mechanical stirrer for 3h, the solid was filtered. After 3 washes (HFIP was recycled through simple distillation using a Rotovap), the material was obtained without any additional PET (as tested by DSC).

Blown molding to raise balloons and obtain thin films was done using a Jandis TINY 25 pilot machine. The quantities and pictures of the balloons can be seen in Fig. 9, but the concept was to maintain an overall consistent amount of recycled quantity in each experiment. That said, we further pushed the limits by introducing up to 10% PE/PET, which would represent recycling the multilayered material, and not just the PE films. The obtained films were tested for different mechanical properties, which are relevant to the standards they follow. Results are also summarized in Fig. 7.

The effect of the additive in terms of mechanical properties is not consistently good or bad. For the transparent recycled material, the additive slightly improved strength while reducing strain %, but decayed puncture and tear MD. For the colored recycled, the additive really improved properties: slightly improved strength (TD) and strain % (TD); significantly improved puncture and tear (MD/TD). Finally, the material having 10% recycled PE/PET (milled) had a significantly reduced strain % and lower puncture.

Example 13

Our process of milling a polymer in a high-energy ball mill leads to polymer mechanochemistry and reduction of molecular weight, which leads to a reduction in viscosity and, consequently, MFI. Moreover, Big-bags are made of PP but contain 10- 25 % PE, which leads to reduction in impact due to the creation of different plastic domains, and our process produce PE-co-PP which can reduce such domains. Therefore, we milled big-bags alone after shredding (Example 11). The material was compounded to test if MFI (and impact) were improved. Composition and results are summarized in Table 1.

Table 1. Sample composition, MFI and impact results for samples tested, including the milled bigbags.

Sample #1 has 75% recycled bigbags, 50% were milled under high energy ball mill, and it contains 5% of a commercial PP/PE compatibilizer. Comparing #1 and #2, an -80% improvement in the flow (16 vs. 9) and -46% improvement in the Impact Notched (80 vs. 55) was seen by using milled material instead of non-milled. Importantly, the additive showed again that this type of additives can improve impact (32% #2 vs. #3), but not MFI. Commercial flow enhancers (#4, #5 and #6) have mixed results, some improve flow, others don't, those that improve flow reduce impact, and therefore, milled material was the only case where a substantial increase in MFI and impact resistance were seen.

Example 14

During Example 11 (PP/PE), samples of material were taken from the ball mill and separated according to size using a mesh. They are defined as 3 groups: virgin (similar to material as added - compounded bigbags), squashed, and powder. Each material was analyzed for its melt flow index MFI (Fig. 8). When the material undergoes complete milling to powder, very high MFI is seen. When it is just hit a few times (squashed), some improvement is seen but not nearly as much as the powdery material.

Claims

CLAIMS:

1. A mechano-chemical process for recycling a polymeric waste material, the process comprising mechanically grinding the waste material under mechanical conditions sufficient to cause polymers in said waste material to undergo chain scission into size reduced polymeric materials and polymer chain reassembly into block copolymers and grafted block copolymer, wherein the mechanical conditions comprise application of high mechanical energy under low temperatures, in absence of carbon dioxide and optionally absence of a solvent.

2. The process according to claim 1, wherein the polymeric waste material is free of or is substantially free of block copolymers and grafted block copolymers.

3. The process according to claim 1, to obtain a polymeric mass comprising or consisting the size reduced polymeric materials, the block copolymers and/or the grafted block copolymer in a form of particles of a size range between 20 and 1,000 microns.

4. The process according to claim 3, wherein the polymeric mass is a thermoplastic polymeric mixture.

5. The process according to any one of the preceding claims, wherein the waste material is or comprises post-industrial polymeric products or objects or post-consumer polymeric products or objects.

6. The process according to any one of the preceding claims, wherein the waste material contains at least one polyolefin.

7. The process according to any one of the preceding claims, wherein the waste material contains a polyolefin selected from polyethylene, polypropylene, and/or copolymers thereof.

8. The process according to claim 6 or 7, wherein the amount of the at least one polyolefin is between 50 and 100wt%.

9. The process according to any one of claims 6 to 8, wherein the polyolefin is selected from high-density and high-molecular-weight polyethylene, high-density polyethylene (HDPE), linear-low-density polyethylene (LLDPE), low-density polyethylene (LDPE) and polypropylene.

10. The process according to any one of claims 6 to 8, wherein the waste material comprises a polyolefin being or comprising high-molecular-weight polyethylene and/or high-density polyethylene (HDPE) and/or linear-low-density polyethylene (LLDPE) and/or low-density polyethylene (LDPE) in combination with polyethylene terephthalate (PET).

11. The process according to any one of claims 6 to 10, wherein the polyolefin is PE, PP or mixtures thereof.

12. The process according to any one of claims 6 to 11, wherein the polymeric waste material comprises PP and/or PE, and one or more other polymeric materials.

13. The process according to claim 12, wherein the polymeric waste material comprises PP and/or PE and polyethylene terephthalate (PET).

14. The process according to claim 1, wherein the polymeric waste material comprises or consists:

-at least one polyolefin being or comprising high-molecular- weight polyethylene and/or high-density polyethylene (HDPE) and/or linear-low-density polyethylene (LLDPE) and/or low-density polyethylene (LDPE);

-polyethylene terephthalate (PET) and at least one polyolefin;

-polyethylene and PET; or

-polyethylene and polypropylene.

15. The process according to any one of the preceding claims, wherein the mechanical grinding is achievable in a ball or pebble mill, jet mill, hammer mill, rod mill, three-roll mill, extruder, crusher, pulverizer, kneader, high shear disperser, homogenizer, ribbon mixer, double planetary mixer, or rotor stator mixer.

16. The process according to claim 15, wherein the mechanical grinding is achievable by ball milling.

17. The process according to any one of the preceding claims, wherein the low temperature is a temperature below the melting temperature of the polymeric waste.

18. The process according to claim 17, wherein the low temperature is between -200°C (200 degrees below zero°C) and 80°C.

19. The process according to claim 17, wherein the low temperature is between 0 and 80°C.

20. The process according to claim 1, the process comprising mechanically grinding in a ball mill the waste material at a temperature between -200°C and 80°C to cause polymers in said waste material to undergo chain scission to obtain size reduced polymeric materials and/or block copolymers and/or grafted block copolymer.

21. The process according to claim 1, the process comprising mechanically grinding in a ball mill the waste material comprising at least one polyolefin at a temperature between -200°C and 80°C to cause the polyolefin to undergo chain scission to obtain polyolefins of reduced molecular weights and/or block copolymers of said polyolefin and/or grafted block copolymer of said polyolefin.

22. The process according to claim 21, wherein the at least one polyolefin is PP and PE provided in combination with PET, to obtain a polymeric mass comprising or consisting one of more of a size reduced PP, a size reduced PE, a size reduced PET, a block copolymer of PP and PE, a grafted block copolymer of PP and PE, a block copolymer of PP and PET, a block copolymer of PE and PET, a grafted block copolymer of PP and PET and/or a grafted block copolymer of PE and PET.

23. The process according to any one of the preceding claims, the process comprises obtaining the waste material.

24. The process according to any one of the preceding claims, the process comprises pretreating the waste material by one or more of washing the waste material, separating metallic objects, and/or shredding or reducing in size the waste material.

25. The process according to any one of the preceding claims, the process comprises:

-obtaining a waste material comprising plastic or an olefinic material,

26. A polymeric mass formed according to any one of claims 1 to 25.

27. The polymeric mass according to claim 26, in a form of thermoplastic particles.

28. The polymeric mass according to claim 26, for use as a compatibilizer.

29. The polymeric mass according to any one of claims 26 to 28, comprises one or more of size-reduced polymers having a molecular weight or a length shorter than the corresponding polymers in the waste material, block copolymers formed from the size- reduced polymers and grafted block copolymers formed from the size reduced polymers.

30. The polymeric mass according to any one of claims 26 to 28, comprising one or a mixture of:

-block copolymer of PE and PET,

-block copolymer of PP and PET,

-block copolymer of PP and PE,

-grafted block copolymer of PE and PET,

-grafted block copolymer of PP and PET,

-grafted block copolymer of PP and PE,

31. The polymeric mass according to any one of claims 26 to 28, comprising a mixture of:

-block copolymer of PE and PET, and

32. The polymeric mass according to any one of claims 26 to 28, comprising a mixture of: -block copolymer of PP and PET,

-size reduced PP, wherein the reduction in size is a reduction by at least 20, 30, 40 or 50%, and/or

33. The polymeric mass according to any one of claims 26 to 28, comprising a mixture of:

-block copolymer of PP and PE,

40 or 50%, and/or

34. The polymeric mass according to any one of claims 26 to 28, comprising a mixture of:

-block copolymer of PE and PET ; and/or

-grafted block copolymer of PE and PET,

40 or 50%, and/or

35. The polymeric mass according to any one of claims 26 to 28, comprising a mixture of:

-block copolymer of PP and PET, and/or

-grafted block copolymer of PP and PET,

40 or 50%, and/or

36. The polymeric mass according to any one of claims 26 to 28, comprising a mixture of:

-block copolymer of PP and PE, and/or -grafted block copolymer of PP and PE, -size reduced PP, wherein the reduction in size is a reduction by at least 20, 30, 40 or 50%, and/or

37. The method according to any one of claims 1 to 25, for recycling the waste polymeric material into a thermoplastic polymeric mass having a different composition of matter, wherein the polymeric mass is according to any one of claims 30 to 36.