WO2013118132A1 - A process for conversion of grey acrylic fiber waste to acrylic powder - Google Patents

A process for conversion of grey acrylic fiber waste to acrylic powder Download PDF

Info

Publication number
WO2013118132A1
WO2013118132A1 PCT/IN2012/000197 IN2012000197W WO2013118132A1 WO 2013118132 A1 WO2013118132 A1 WO 2013118132A1 IN 2012000197 W IN2012000197 W IN 2012000197W WO 2013118132 A1 WO2013118132 A1 WO 2013118132A1
Authority
WO
WIPO (PCT)
Prior art keywords
acrylic
polymer
solvents
novel process
volume
Prior art date
Application number
PCT/IN2012/000197
Other languages
French (fr)
Inventor
Omid ADAB
Abbas ADAB
Original Assignee
Adab Omid
Adab Abbas
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Adab Omid, Adab Abbas filed Critical Adab Omid
Publication of WO2013118132A1 publication Critical patent/WO2013118132A1/en

Links

Classifications

    • D—TEXTILES; PAPER
    • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
    • D01F13/00—Recovery of starting material, waste material or solvents during the manufacture of artificial filaments or the like
    • D01F13/04—Recovery of starting material, waste material or solvents during the manufacture of artificial filaments or the like of synthetic polymers
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J11/00—Recovery or working-up of waste materials
    • C08J11/04—Recovery or working-up of waste materials of polymers
    • C08J11/06—Recovery or working-up of waste materials of polymers without chemical reactions
    • D—TEXTILES; PAPER
    • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
    • D01F6/00—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof
    • D01F6/02—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolymers obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • D01F6/18—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolymers obtained by reactions only involving carbon-to-carbon unsaturated bonds from polymers of unsaturated nitriles, e.g. polyacrylonitrile, polyvinylidene cyanide
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2333/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Derivatives of such polymers
    • C08J2333/18—Homopolymers or copolymers of nitriles
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
    • Y02P70/62—Manufacturing or production processes characterised by the final manufactured product related technologies for production or treatment of textile or flexible materials or products thereof, including footwear
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W30/00—Technologies for solid waste management
    • Y02W30/50—Reuse, recycling or recovery technologies
    • Y02W30/62—Plastics recycling; Rubber recycling

Definitions

  • the present invention relates to a novel process for converting grey acrylic fiber waste to acrylic powder which can be used in acrylic fiber production line without affecting the properties of virgin acrylic fiber.
  • Acrylic polymer is widely formed by free-radical polymerization in aqueous suspension.
  • the acrylic polymer formed is purified by series of filtration and washing sequence with DM water, dried and pulverized for fiber production.
  • the fiber is produced by dissolving the polymer in solvents such as N,N- dimethylformamide (DMF); dimethyl sulfoxide (DMSO); aqueous sodium thiocyanate (NaSCN) or dimethylacetamide (DMAc) in a precise concentration along with other additives; metering it through a multi-hole spinnerets and coagulating the resultant filaments in an aqueous solution of the same solvent (wet spinning) or evaporating the solvent in a stream of heated inert gas (dry spinning). This follows by washing, stretching, drying and crimping to form acrylic tow and staples fiber.
  • solvents such as N,N- dimethylformamide (DMF); dimethyl sulfoxide (DMSO); aqueous sodium thio
  • the acrylic fiber wastes are generated in different stages of fiber production line in the form of acrylic soft waste, acrylic tangled tow waste, acrylic off grade soft and hard waste etc.
  • I wastes find their market in Asian countries, where they are subjected to manual separation and production of yarn either in the actual form or blending with other fibers.
  • the acrylic fiber wastes also find application in manufacturing of acrylic base adhesives and paints.
  • the main object of the invention is to develop an economical and environment friendly waste utilization process for grey acrylic fiber waste.
  • Another object of this invention is to convert grey acrylic fiber waste generated during the fiber production into acrylic powder.
  • Yet another object of this invention is to devise a novel process whereby grey acrylic fiber waste could be converted into acrylic powder for its usage as a raw material for the acrylic fiber production line.
  • a further object of this invention is to develop a method to manufacture acrylic powder from acrylic fiber waste without affecting the original properties of virgin acrylic fiber.
  • An additional object of this invention is to propose a process whereby the solvents used during the process could be recycled to the system minimizing the effect to the environment and reducing the conversion cost.
  • An additional object of the invention is to minimize the use of water in precipitation process to reduce the chances of water pollution on account of additives in the fiber waste and solvents used in the process.
  • a novel process for conversion of grey acrylic fiber waste to acrylic powder comprising of the steps of (a) dissolving the acrylic wastes in solvents such as N,N- dirhethylformamide (DMF), dimethyl sulfoxide (DMSO), dimethylacetamide (DMAc), aqueous solution of sodium thiocyariate (NaSCN) but not limited to above mentioned solvents in the concentration of 1-25% and temperature of not more than 90°C; (b) filtration through any coarse filter media to remove any un-dissolved and other impurities before precipitation; (c) precipitation of acrylic polymer from the solution using any commercially available primary-, secondary- and tertiary alcohols in the ratio of 1 : 1 to 1: 10 volume by volume of polymer solution and alcohols; (d) vacuum filtration to remove the solvents mixture; (e) dispersing the polymer in hot/ cold DM water in the ratio of 1:5 to 1 :20 weight by volume to remove residual solvents; (e)
  • solvents such as N
  • the present novel invention involves an economical and environment friendly process to convert grey acrylic fiber waste generated during the fiber production into acrylic powder which could be used as a raw material for the acrylic fiber production line without affecting the original properties of virgin acrylic fiber.
  • solvents used can be recycled to the system minimizing the effect to the environment and reducing the conversion cost.
  • grey acrylic fiber waste is dissolved in appropriate solvents such as N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), dimethylacetamide (DMAc), aqueous solution of sodium thiocyanate (NaSCN) but not limited to the given examples in the concentration of 1-25% weight by volume at a temperature not exceeding 95°C.
  • appropriate solvents such as N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), dimethylacetamide (DMAc), aqueous solution of sodium thiocyanate (NaSCN)
  • the polymer solution is then subjected to coarse filtration in order to remove non-acrylic foreign particles from the solution to get clear acrylic solution and the filtrate is mixed with any commercially available aliphatic primary, secondary and tertiary alcohols such as methanol, ethanol, n-propanol, n-butanol, isopropyl alcohol, tert- butyl alcohol or by combination of any of them in the ratio 1: 1 to 1 : 10 of polymer solution : alcohol for effective precipitation process of dissolved acrylic polymer whereby the solvent and precipitating agent/ s are remove by filtration preferably vacuum filtration process.
  • any commercially available aliphatic primary, secondary and tertiary alcohols such as methanol, ethanol, n-propanol, n-butanol, isopropyl alcohol, tert- butyl alcohol or by combination of any of them in the ratio 1: 1 to 1 : 10 of polymer solution : alcohol for effective precipitation process of dissolved acrylic polymer where
  • the precipitates are suspended in adequate media such as alcohols or demineralised (DM) water in the concentration of 1:5 to 1:20 to remove the traces of DMF, DMAc, DMSO or NaSCN and repeated filtration process to obtain purified polymer.
  • adequate media such as alcohols or demineralised (DM) water in the concentration of 1:5 to 1:20 to remove the traces of DMF, DMAc, DMSO or NaSCN and repeated filtration process to obtain purified polymer.
  • the wet cake undergoes a drying process either in its existing form or by converting it to noodles using extruder before drying in continuous belt dryer followed by pulverization in which the acrylic polymer is converted to fine powdered before sieving and sending to storage bins.
  • the solvents used in the process are recovered and reused in subsequent process.
  • the intrinsic viscosities of the recycled acrylic polymer powders were in the range of 1.40 ⁇ 0.02 matching the intrinsic viscosity of the original acrylic polymers.
  • Intrinsic viscosity is obtained by determining the relative viscosity for 0.2% W/V solution of polymer in 0.2 Molar Lithium Bromide/ DMF Solvent at 25°C.
  • acrylic fiber 6.8 gm was dissolved in 100 ml of hot NaSCN aqueous solution (90% weight by volume), cooled and precipitated with 250 ml of Ethanol. The mixture is filtered and the white lumps were suspended in 100 ml of Ethanol. Filtered and again suspended in 200 ml of DM water to ensure complete removal of NaSCN traces and ethanol. Filtered and dried in oven followed by pulverization to get fine white acrylic powder.
  • 7.5 gm of acrylic fiber was dissolved in 75 ml of hot DMSO, cooled and precipitated with 300 ml of n-Propanol. The mixture is filtered and the white lumps were suspended in 150 ml of hot DM water, filtered and procedure was repeated to ensure complete removal of DMSO and alcohol. Dried in oven and pulverized to have fine acrylic powder.

Abstract

The invention discloses a process for conversion of grey acrylic fiber waste to acrylic powder comprising of the steps of (a) dissolving the acrylic wastes in a solvent in the concentration of 1-25% and temperature of not more than 90°C; (b) filtration through any coarse filter media to remove any un-dissolved and other impurities before precipitation; (c) precipitation of acrylic polymer from the solution using any commercially available primary-, secondary- and tertiary alcohols in the ratio of 1:1 to 1:10 volume by volume of polymer solution and alcohols; (d) vacuum filtration to remove the solvents mixture; (e) dispersing the polymer in hot/cold DM water in the ratio of 1:5 to 1:20 weight by volume to remove residual solvents; (e) pelletizing the wet precipitate before drying or directly drying the polymer at elevated temperature to remove moisture; (f) pulverizing the dried polymer and sieving to obtain fine acrylic powder; (g) recovering the used solvents by distillation process.

Description

A PROCESS FOR CONVERSION OF GREY ACRYLIC FIBER WASTE TO ACRYLIC POWDER
FIELD OF INVENTION:
The present invention relates to a novel process for converting grey acrylic fiber waste to acrylic powder which can be used in acrylic fiber production line without affecting the properties of virgin acrylic fiber.
BACKGROUND OF INVENTION:
Acrylic polymer is widely formed by free-radical polymerization in aqueous suspension. The acrylic polymer formed is purified by series of filtration and washing sequence with DM water, dried and pulverized for fiber production. The fiber is produced by dissolving the polymer in solvents such as N,N- dimethylformamide (DMF); dimethyl sulfoxide (DMSO); aqueous sodium thiocyanate (NaSCN) or dimethylacetamide (DMAc) in a precise concentration along with other additives; metering it through a multi-hole spinnerets and coagulating the resultant filaments in an aqueous solution of the same solvent (wet spinning) or evaporating the solvent in a stream of heated inert gas (dry spinning). This follows by washing, stretching, drying and crimping to form acrylic tow and staples fiber.
The acrylic fiber wastes are generated in different stages of fiber production line in the form of acrylic soft waste, acrylic tangled tow waste, acrylic off grade soft and hard waste etc. These
I wastes find their market in Asian countries, where they are subjected to manual separation and production of yarn either in the actual form or blending with other fibers. The acrylic fiber wastes also find application in manufacturing of acrylic base adhesives and paints.
The global demands for synthetic fiber and higher cost of acrylic fibers in compare to polyester fibers require measures to minimize the waste and reduce the production cost.
Considering the need for recycling the acrylic fiber waste, it was found necessary to find an cost effective method for converting the acrylic fiber wastes in any form to acrylic powder which could be easily mixed with the virgin pulverized acrylic polymer and introduced in manufacturing process, minimizing the waste generation and reducing the production cost.
OBJECTS OF INVENTION;
The main object of the invention is to develop an economical and environment friendly waste utilization process for grey acrylic fiber waste.
Another object of this invention is to convert grey acrylic fiber waste generated during the fiber production into acrylic powder.
Yet another object of this invention is to devise a novel process whereby grey acrylic fiber waste could be converted into acrylic powder for its usage as a raw material for the acrylic fiber production line. A further object of this invention is to develop a method to manufacture acrylic powder from acrylic fiber waste without affecting the original properties of virgin acrylic fiber.
An additional object of this invention is to propose a process whereby the solvents used during the process could be recycled to the system minimizing the effect to the environment and reducing the conversion cost.
An additional object of the invention is to minimize the use of water in precipitation process to reduce the chances of water pollution on account of additives in the fiber waste and solvents used in the process.
STATEMENT OF INVENTION;
According to this invention, there is provided a novel process for conversion of grey acrylic fiber waste to acrylic powder comprising of the steps of (a) dissolving the acrylic wastes in solvents such as N,N- dirhethylformamide (DMF), dimethyl sulfoxide (DMSO), dimethylacetamide (DMAc), aqueous solution of sodium thiocyariate (NaSCN) but not limited to above mentioned solvents in the concentration of 1-25% and temperature of not more than 90°C; (b) filtration through any coarse filter media to remove any un-dissolved and other impurities before precipitation; (c) precipitation of acrylic polymer from the solution using any commercially available primary-, secondary- and tertiary alcohols in the ratio of 1 : 1 to 1: 10 volume by volume of polymer solution and alcohols; (d) vacuum filtration to remove the solvents mixture; (e) dispersing the polymer in hot/ cold DM water in the ratio of 1:5 to 1 :20 weight by volume to remove residual solvents; (e) palletizing the wet precipitate before drying or directly drying the polymer at elevated temperature to remove moisture; (f) pulverizing the dried polymer and sieving to obtain fine acrylic powder, (g) recovering the used solvents by distillation.
DETAILED DESCRIPTION OF THE INVENTION:
The present novel invention involves an economical and environment friendly process to convert grey acrylic fiber waste generated during the fiber production into acrylic powder which could be used as a raw material for the acrylic fiber production line without affecting the original properties of virgin acrylic fiber. In this process, solvents used can be recycled to the system minimizing the effect to the environment and reducing the conversion cost.
In the instant invention, grey acrylic fiber waste is dissolved in appropriate solvents such as N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), dimethylacetamide (DMAc), aqueous solution of sodium thiocyanate (NaSCN) but not limited to the given examples in the concentration of 1-25% weight by volume at a temperature not exceeding 95°C.
The polymer solution is then subjected to coarse filtration in order to remove non-acrylic foreign particles from the solution to get clear acrylic solution and the filtrate is mixed with any commercially available aliphatic primary, secondary and tertiary alcohols such as methanol, ethanol, n-propanol, n-butanol, isopropyl alcohol, tert- butyl alcohol or by combination of any of them in the ratio 1: 1 to 1 : 10 of polymer solution : alcohol for effective precipitation process of dissolved acrylic polymer whereby the solvent and precipitating agent/ s are remove by filtration preferably vacuum filtration process.
The precipitates are suspended in adequate media such as alcohols or demineralised (DM) water in the concentration of 1:5 to 1:20 to remove the traces of DMF, DMAc, DMSO or NaSCN and repeated filtration process to obtain purified polymer.
The wet cake undergoes a drying process either in its existing form or by converting it to noodles using extruder before drying in continuous belt dryer followed by pulverization in which the acrylic polymer is converted to fine powdered before sieving and sending to storage bins.
The solvents used in the process are recovered and reused in subsequent process.
It is pertinent to mention here that the intrinsic viscosities of the recycled acrylic polymer powders were in the range of 1.40 ± 0.02 matching the intrinsic viscosity of the original acrylic polymers. Intrinsic viscosity is obtained by determining the relative viscosity for 0.2% W/V solution of polymer in 0.2 Molar Lithium Bromide/ DMF Solvent at 25°C.
Examples
Example: 1
8 gm of acrylic fiber was dissolved in 100 ml of hot DMAc, cooled and precipitated with 180 ml of n-Propanol. The mixture is filtered and the white lumps were suspended in 100 ml of hot DM water, filtered and procedure was repeated to ensure complete removal of DMAc and alcohol. Dried in oven and pulverized to have fine acrylic powder.
Example: 2
6.8 gm of acrylic fiber was dissolved in 100 ml of hot NaSCN aqueous solution (90% weight by volume), cooled and precipitated with 250 ml of Ethanol. The mixture is filtered and the white lumps were suspended in 100 ml of Ethanol. Filtered and again suspended in 200 ml of DM water to ensure complete removal of NaSCN traces and ethanol. Filtered and dried in oven followed by pulverization to get fine white acrylic powder.
Example: 3
7.5 gm of acrylic fiber was dissolved in 75 ml of hot DMSO, cooled and precipitated with 300 ml of n-Propanol. The mixture is filtered and the white lumps were suspended in 150 ml of hot DM water, filtered and procedure was repeated to ensure complete removal of DMSO and alcohol. Dried in oven and pulverized to have fine acrylic powder.
It is to be noted that the present invention is susceptible to modifications, adaptations and changes by those skilled in the art. Such variant embodiments employing the concepts and features of this invention are intended to be within the scope of the present invention, which is further set forth under the following claims:

Claims

A novel process for conversion of grey acrylic fiber waste to acrylic powder comprising of the steps of: a. dissolving the acrylic wastes in solvents such as N,N- dimethylformamide (DMF), dimethyl sulfoxide (DM SO), dimethylacetamide (DMAc), aqueous solution of sodium thiocyanate (NaSCN) but not limited to above mentioned solvents in the Concentration of 1-25% and temperature of not more than 90°C; b. filtration through any coarse filter media to remove any un-dissolved and other impurities before precipitation; c. precipitation of acrylic polymer from the solution using any commercially available primary-, secondary- and tertiary alcohols in the ratio of 1: 1 to 1: 10 volume by volume of polymer solution and alcohols; d. vacuum filtration to remove the solvents mixture; e. dispersing the polymer in hot/ cold DM water in the ratio of 1:5 to 1:20 weight by volume to remove residual solvents; f. palletizing the wet precipitate before drying or directly drying the polymer at elevated temperature to remove moisture; g. pulverizing the dried polymer and sieving to obtain fine acrylic powder; h. recovery of used solvents using distillation process.
2. A novel process as claimed in claim 1 where the concentration of acrylic fiber waste to solvent or solvents mixture is in the range of 1-25% weight by volume.
3. A novel process as claimed in claim 1 wherein the precipitating agent(s) is/ are any commercially available aliphatic primary, secondary and tertiary alcohols.
4. A novel process as claimed in claim 3 wherein the precipitating agent(s) can be single or mixture of said aliphatic alcohols.
5. A novel process as claimed in proceeding claims wherein the purification of polymer precipitate is carried out hot/ cold demineralised (DM) water in the concentration of 1:5 to 1 :20.
6. A novel process as claimed in proceeding claims wherein the further dispersion and purification is done using hot/ cold DM water to ensure complete removal of solvents from polymer precipitates.
7. A novel process as claimed in claim 1 wherein the wet polymer is converted to noodles using extruder before drying in continuous belt dryer.
8. A novel process for conversion of grey acrylic fiber waste to acrylic powder as herein substantially described read in conjunction with the accompanying examples.
PCT/IN2012/000197 2012-02-10 2012-03-26 A process for conversion of grey acrylic fiber waste to acrylic powder WO2013118132A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IN372/DEL/2012 2012-02-10
IN372DE2012 IN2012DE00372A (en) 2012-02-10 2012-03-26

Publications (1)

Publication Number Publication Date
WO2013118132A1 true WO2013118132A1 (en) 2013-08-15

Family

ID=46125484

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IN2012/000197 WO2013118132A1 (en) 2012-02-10 2012-03-26 A process for conversion of grey acrylic fiber waste to acrylic powder

Country Status (2)

Country Link
IN (1) IN2012DE00372A (en)
WO (1) WO2013118132A1 (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2862895A (en) * 1955-10-11 1958-12-02 American Cyanamid Co Method of recovering crumb of a polymer of a polymerized compund containing a singlech2=c< grouping from by-product material solutions
GB1084563A (en) * 1964-01-31 1967-09-27 Zaklady Wlokien Sztucznych Ani Method for preparing a spinning solution from waste arising during the production offibres of acrylonitrile polymers or copolymers
DD200233A1 (en) * 1981-09-10 1983-03-30 Ulrich Loerzer METHOD FOR PROCESSING THERMALLY LOADED ACRYLIC NITRILE-CONTAINING FIBER AND FORMKOERPER ABFAELLEN FOR DIRECT REPLACEMENT
CN1105406A (en) * 1994-01-10 1995-07-19 钱德明 Technique for producing spinnable acrylic fibre using waste acrylic viscose fibre
US20030191202A1 (en) * 2000-08-11 2003-10-09 Andreas Maurer Method for separating and recovering target polymers and their additives from a material containing polymers

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2862895A (en) * 1955-10-11 1958-12-02 American Cyanamid Co Method of recovering crumb of a polymer of a polymerized compund containing a singlech2=c< grouping from by-product material solutions
GB1084563A (en) * 1964-01-31 1967-09-27 Zaklady Wlokien Sztucznych Ani Method for preparing a spinning solution from waste arising during the production offibres of acrylonitrile polymers or copolymers
DD200233A1 (en) * 1981-09-10 1983-03-30 Ulrich Loerzer METHOD FOR PROCESSING THERMALLY LOADED ACRYLIC NITRILE-CONTAINING FIBER AND FORMKOERPER ABFAELLEN FOR DIRECT REPLACEMENT
CN1105406A (en) * 1994-01-10 1995-07-19 钱德明 Technique for producing spinnable acrylic fibre using waste acrylic viscose fibre
US20030191202A1 (en) * 2000-08-11 2003-10-09 Andreas Maurer Method for separating and recovering target polymers and their additives from a material containing polymers

Also Published As

Publication number Publication date
IN2012DE00372A (en) 2015-05-15

Similar Documents

Publication Publication Date Title
WO2019001137A1 (en) Method for manufacturing textile waste into fiber grade polyester chips applicable to textile processing
US20130289204A1 (en) Polyimide powder, polyimide solution, and method for producing polyimide powder
CN102127169A (en) Preparation method of cellulose acetate propionate
CN104759151A (en) Magnetic composite filter material prepared by blending melt-blown polypropylene with modified volcanic rock and used for sewage treatment and preparation method thereof
CN108368289A (en) PA/PET separation methods
CN103275320B (en) Front desalination process prepares the method for linear high molecular weight polyphenylene sulfide
CN100503569C (en) Method for preparing 4,4&#39;- bi (4 - carboxyl phthalimide group) 3,3&#39;- dimethyl diphenylmothane
WO2019047176A1 (en) Method for recycling waste polyester-cotton blend fabrics
WO2013118132A1 (en) A process for conversion of grey acrylic fiber waste to acrylic powder
CN103289093A (en) Method for preparing linear high molecular weight polyphenylene sulfide
JP6704923B2 (en) Method for obtaining ore dust control resin, ore dust control resin, method for control of ore particle emission and use of resin
CN104844819A (en) Modified polyimide film and modified polyimide precursor composite film waste material recovery processing method
CN104759147A (en) High-efficient composite filter material prepared by blending melt-blown polypropylene with modified activated carbon and used for sewage treatment and preparation method thereof
TWI694064B (en) Method for manufacturing terephthalic acid and system thereof
CN116769231A (en) Recycling method for mild and efficient selective hydrolysis of waste high polymer material based on polyester
CN102863621A (en) Polyphenylene sulfide resin refining method
CN113549347A (en) Surface modification method of carbon black
CN106496716A (en) A kind of junked tire reclaims modified technique
CN205851119U (en) A kind of polyarylate resin production centrifuge
CN105017560A (en) Waste recovery processing method for modified polyimide precursor composition film
CN110845759B (en) Method for removing excessive dihydric alcohol in alcoholysis liquid
CN110776069B (en) Impurity removal method for chain decomposition of waste polyester product solution by precipitation adsorption method
CN113980349B (en) PET waste recycling and regenerating method and anti-aging polyester material prepared by same
CN104759149A (en) High-activity composite filter material prepared by blending melt-blown polypropylene with modified kaolin and used for sewage treatment and preparation method thereof
CN117801269A (en) Method for chemically recycling and repolymerizing nylon 12

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 12722200

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 12722200

Country of ref document: EP

Kind code of ref document: A1