The present invention concerns a process for decolorizing a polyolefin composition, the process comprising the steps of a) providing a polyolefin composition comprising at least one polyolefin and at least one organic chromophore, b) mixing the polyolefin composition in a melt state at a temperature of 170 to 290° C. with an inorganic oxidizing agent, wherein the inorganic oxidizing agent is selected from the group of inorganic peroxides and hypochlorites, and c) obtaining a decolorized polyolefin composition.

The present invention concerns a process for decolorizing a polyolefin composition, the process comprising the steps of a) providing a polyolefin composition comprising at least one polyolefin and at least one organic chromophore, b) mixing the polyolefin composition in a melt state at a temperature of 170 to 290° C. with an inorganic oxidizing agent, wherein the inorganic oxidizing agent is selected from the group of inorganic peroxides and hypochlorites, and c) obtaining a decolorized polyolefin composition.

A process for chemically recycling polyethylene terephthalate (PET) which utilizes a microwave absorber to optimize glycolytic depolymerization of PET via microwave irradiation. The method of chemically degrading PET to its reactive intermediate, bis(2-hydroxyethyl) terephthalate (BHET), is carried out by: (a) combining PET with ethylene glycol and a catalytic system comprising a catalyst and a microwave absorber to produce a heterogeneous reaction mixture; and then (b) heating by microwave irradiating the reaction mixture to a temperature sufficient to produce a reaction product comprising BHET. The BHET monomer then can be purified and re-polymerized to form new, virgin PET.

A process for chemically recycling polyethylene terephthalate (PET) which utilizes a microwave absorber to optimize glycolytic depolymerization of PET via microwave irradiation. The method of chemically degrading PET to its reactive intermediate, bis(2-hydroxyethyl) terephthalate (BHET), is carried out by: (a) combining PET with ethylene glycol and a catalytic system comprising a catalyst and a microwave absorber to produce a heterogeneous reaction mixture; and then (b) heating by microwave irradiating the reaction mixture to a temperature sufficient to produce a reaction product comprising BHET. The BHET monomer then can be purified and re-polymerized to form new, virgin PET.

A degradable resin composition comprising at least one benzoxazine group in a backbone or as an endcap and at least one cleavable covalent bond is provided. Also provided is a thermoset composition comprising a cured benzoxazine-based resin composition including at least one imine group. A degradable resin composition comprising at least one benzoxazine group in a backbone or an endcap, at least one acetal group, and at least one acrylate group is also provided. A method of recycling a resin composition includes providing a cured polymer resin composite which comprises a cured benzoxazine-based resin composition including at least one cleavable covalent bond, and fibers. The method then includes exposing the cured polymer resin composite to an acid, thereby cleaving the at least one cleavable covalent bond to produce a degraded polymer resin, and removing the fibers from the degraded polymer resin.

A degradable resin composition comprising at least one benzoxazine group in a backbone or as an endcap and at least one cleavable covalent bond is provided. Also provided is a thermoset composition comprising a cured benzoxazine-based resin composition including at least one imine group. A degradable resin composition comprising at least one benzoxazine group in a backbone or an endcap, at least one acetal group, and at least one acrylate group is also provided. A method of recycling a resin composition includes providing a cured polymer resin composite which comprises a cured benzoxazine-based resin composition including at least one cleavable covalent bond, and fibers. The method then includes exposing the cured polymer resin composite to an acid, thereby cleaving the at least one cleavable covalent bond to produce a degraded polymer resin, and removing the fibers from the degraded polymer resin.

A method for improving a recovery rate of recycled bis(2-hydroxyethyl) terephthalate (BHET) is provided, which includes: providing a recycled polyester fabric; using a chemical de-polymerization liquid to chemically depolymerize the recycled polyester fabric, so as to form a de-polymerization product containing BHET; dissolving the BHET in water to form a aqueous phase liquid; cooling the aqueous phase liquid from a dissolution temperature to a first crystallization temperature, so as to crystallize at least a part of the BHET; and cooling the aqueous phase liquid from the first crystallization temperature to a second crystallization temperature, so as to crystallize at least another part of the BHET.

A method for improving a recovery rate of recycled bis(2-hydroxyethyl) terephthalate (BHET) is provided, which includes: providing a recycled polyester fabric; using a chemical de-polymerization liquid to chemically depolymerize the recycled polyester fabric, so as to form a de-polymerization product containing BHET; dissolving the BHET in water to form a aqueous phase liquid; cooling the aqueous phase liquid from a dissolution temperature to a first crystallization temperature, so as to crystallize at least a part of the BHET; and cooling the aqueous phase liquid from the first crystallization temperature to a second crystallization temperature, so as to crystallize at least another part of the BHET.

A method of obtaining a purified regenerated diacid from a depolymerization of a polyester in a waste material wherein the depolymerization provides a depolymerized mixture comprising a regenerated diol, a regenerated diacid, and a catalyst is disclosed. The method comprises: separating a regenerated composition including the regenerated acid and the catalyst from the regenerated diol; providing the regenerated composition in a liquid medium to form a pre-aged mixture; subjecting the pre-aged mixture to thermal cycling wherein the cycling occurs within 25° C. and within a temperature range of from 150° C. or more to 300° C. or less to form an aged mixture; and separating the regenerated composition from the liquid medium in the aged mixture.

A method of obtaining a purified regenerated diacid from a depolymerization of a polyester in a waste material wherein the depolymerization provides a depolymerized mixture comprising a regenerated diol, a regenerated diacid, and a catalyst is disclosed. The method comprises: separating a regenerated composition including the regenerated acid and the catalyst from the regenerated diol; providing the regenerated composition in a liquid medium to form a pre-aged mixture; subjecting the pre-aged mixture to thermal cycling wherein the cycling occurs within 25° C. and within a temperature range of from 150° C. or more to 300° C. or less to form an aged mixture; and separating the regenerated composition from the liquid medium in the aged mixture.