Method for preparing carbon material using polyolefin-based plastic and carbon material prepared therefrom

Patent metadata

Field	Value
Publication number	US-2019144279-A1
Application number	US-201816188294-A
Country	US
Kind code	A1
Filing date	Nov 13, 2018
Priority date	Nov 14, 2017
Publication date	May 16, 2019
Grant date	—

Abstract

Provided are a method for preparing a carbon material using a polyolefin-based plastic, which includes a step of dissolving a polyolefin-based plastic in a solvent and then precipitating to obtain a polyolefin-based polymer having, for example, a powder or film shape, a step of crosslinking and cyclizing the precipitated polyolefin-based polymer to stabilize the polyolefin-based polymer and to cleave linear bonding of the polyolefin-based polymer, and a step of carbonizing the stabilized polyolefin-based polymer and a carbon material prepared according to this method. According to this method, it is possible to convert polyolefin-based plastics, particularly polyolefin-based waste plastics, into high-quality carbon materials having high heat-generating properties and a high electrical conductivity by a simple and efficient process.

First claim

What is claimed is:

1 . A method for preparing a carbon material using a polyolefin-based plastic, comprising:
a step of dissolving a polyolefin-based plastic in a solvent and then precipitating to obtain a polyolefin-based polymer; a step of crosslinking and cyclizing the precipitated polyolefin-based polymer to stabilize the polyolefin-based polymer and to cleave linear bonding of the polyolefin-based polymer; and a step of carbonizing the stabilized polyolefin-based polymer.

2 . The method for preparing a carbon material using a polyolefin-based plastic according to claim 1 , wherein the method for preparing a carbon material is a non-catalytic process.

3 . The method for preparing a carbon material using a polyolefin-based plastic according to claim 2 , wherein the polyolefin-based plastic is a polyolefin-based waste plastic.

4 . The method for preparing a carbon material using a polyolefin-based plastic according to claim 1 , wherein the polyolefin-based polymer includes one or more polyolefin-based polymers selected from a linear low-density polyolefin (LLDPE), a low-density polyolefin (LDPE), a medium-density polyolefin (MDPE), a high-density polyolefin (HDPE), an ultra high molecular weight polyolefin (UHMWPE), or a crosslinked polyolefin (XLPE).

5 . The method for preparing a carbon material using a polyolefin-based plastic according to claim 1 , wherein a polyolefin-based plastic is dissolved in a solvent and then precipitated to obtain a polyolefin-based polymer in a form of a powder or film in the step of obtaining a polyolefin-based polymer.

6 . The method for preparing a carbon material using a polyolefin-based plastic according to claim 5 , wherein the solvent is a hydrocarbon solvent, a chlorinated hydrocarbon solvent, or an aromatic hydrocarbon solvent.

7 . The method for preparing a carbon material using a polyolefin-based plastic according to claim 5 , wherein the solvent is a trichloroethane, toluene, xylene, dichlorobenzene, trichlorobenzene, tetrahydronaphthalene, or decahydronaphthalene.

8 . The method for preparing a carbon material using a polyolefin-based plastic according to claim 5 , wherein the powder or film obtained is further processed into a form of a film and then subjected to a stabilization step.

9 . The method for preparing a carbon material using a polyolefin-based plastic according to claim 5 , wherein the solvent further contains a crosslinking agent.

10 . The method for preparing a carbon material using a polyolefin-based plastic according to claim 9 , wherein the crosslinking agent is an organic peroxide such as butyl 4,4-bis(tert-butyldioxy)valerate, di-(2,4-dichlorobenzoyl)-peroxide, dibenzoyl peroxide, tert-butyl peroxybenzoate, 1,1-di-(tert-butylperoxy)-3,3,5-trimethylcyclohexane, dicumyl peroxide, di-(2-tert-butylperoxyisopropyl)-benzene, tert-butyl cumyl peroxide, 2,5-dimethyl-2,5-di-(tert-butylperoxy)-hexane, di-tert-butylperoxide, or 2,5-dimethyl-2,5-di(tert-butylperoxy)hexyme-3.

11 . The method for preparing a carbon material using a polyolefin-based plastic according to claim 5 , wherein the stabilization step includes one or more selected from the following processes (a) to (c):
(a) a process of subjecting a polyolefin-based polymer powder or film to a heat treatment for stabilization in an air or oxygen atmosphere at a temperature of 400° C. or less, (b) a process of treating a polyolefin-based polymer powder or film with an acid solution, and (c) a process of treating a polyolefin-based polymer powder or film with one or more physical means selected from plasma, an ion beam, radiation, ultraviolet light, a microwave, or an electron beam.

12 . The method for preparing a carbon material using a polyolefin-based plastic according to claim 11 , wherein a density of the stabilized polyolefin-based polymer powder or film is from 1.2 to 1.6 g/cm 3 .

13 . The method for preparing a carbon material using a polyolefin-based plastic according to claim 11 , wherein the stabilization step is to stabilize a polyolefin-based polymer powder or film in a temperature range of from 130° C. to 350° C. for from 30 minutes to 480 minutes using thermal energy singly or in combination with plasma.

14 . The method for preparing a carbon material using a polyolefin-based plastic according to claim 11 , wherein the stabilization step is carried out by impregnating a polyolefin-based polymer powder or film with a 90% or more aqueous solution of sulfuric acid at a temperature of from 90° C. to 150° C. for from 1 to 4 hours.

15 . The method for preparing a carbon material using a polyolefin-based plastic according to claim 14 , wherein a sulfur content in the stabilized powder or film is more than 0 and 5 at % (atomic %) or less.

16 . The method for preparing a carbon material using a polyolefin-based plastic according to claim 11 , wherein the treatment by a physical means is electron beam irradiation,
total energy by electron beam irradiation is from 50 to 3000 kGy, and the electron beam irradiation is conducted in a temperature range of room temperature or more and 300° C. or less in air.

17 . The method for preparing a carbon material using a polyolefin-based plastic according to claim 11 , wherein the stabilization step is to conduct a heat treatment, a treatment by a physical means, or a heat treatment combined with a treatment by a physical means together with an acid solution treatment or additionally after an acid solution treatment, and
the physical means is one or more physical means selected from plasma, an ion beam, radiation, ultraviolet light, a microwave, or an electron beam.

18 . The method for preparing a carbon material using a polyolefin-based plastic according to claim 5 , wherein the carbonization step is carried out in an inert gas atmosphere or a vacuum atmosphere.

19 . The method for preparing a carbon material using a polyolefin-based plastic according to claim 18 , wherein a stabilized polyolefin-based polymer powder or film is carbonized at a temperature more than 400° C. and 1800° C. or less in the carbonization step.

20 . The method for preparing a carbon material using a polyolefin-based plastic according to claim 19 , further comprising a process of graphitizing the carbonized powder or film at a temperature of from 1800° C. to 3000° C.

Assignees

• Korea Inst Sci & Tech

Inventors

• Choi Dalsu
• Jang Dawon
• Lee Sung Ho

Classifications

• C08J11/12

  by dry-heat treatment only · CPC title

• C08J2323/06

  Polyethene · CPC title

• C08J3/14

  by precipitation from solutions {(C08J3/122 takes precedence)} · CPC title

• C01B32/05 Primary

  Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30 · CPC title

• C08K5/14

  Peroxides · CPC title