Polyamic acids dope composition, preparation method of hollow fiber using the same and hollow fiber prepared therefrom

Abstract

Disclosed herein are a polyamic acid dope solution composition, a method for preparing a hollow fiber using the composition and a hollow fiber prepared by the method. More specifically, disclosed are a method for preparing a hollow fiber, comprising preparing a polyamic acid dope solution composition comprising polyhydroxyamic acid, polythiolamic acid or polyaminoamic acid, spinning the composition to prepare a hollow fiber, and imidizing and thermally rearranging the hollow fiber, and the hollow fiber prepared by the method. In accordance with the method, a hollow fiber made of a high free volume polymer membrane can be prepared by spinning the dope solution composition to prepare a hollow fiber and thermally rearranging the hollow fiber via thermal treatment. The hollow fiber thus prepared exhibits excellent gas permeability and selectivity, thus being suitable for use as a gas separation membrane.

1 . A dope solution composition comprising:
 (a) a polymer for forming a hollow fiber, including one selected from the group consisting of polyamic acids represented by the following Formulae 1 to 4, polyamic acid copolymers represented by Formulae 5 to 8, copolymers thereof and blends thereof;   (b) an organic solvent; and   (c) an additive.   
       
         
           
           
               
               
           
         
         In Formulae 1 to 8, 
         Ar 1  is a tetravalent C 5 -C 24  arylene group or a tetravalent C 5 -C 24  heterocyclic ring, which is substituted or unsubstituted with at least one substituent selected from the group consisting of C 1 -C 10  alkyl, C 1 -C 10  alkoxy, C 1 -C 10  haloalkyl and C 1 -C 10  haloalkoxy, or two or more of which are fused together to form a condensation ring or covalently bonded to each other via a functional group selected from the group consisting of O, S, C(═O), CH(OH), S(═O) 2 , Si(CH 3 ) 2 , (CH 2 ) p  (in which 1≦p≦10), (CF 2 ) q  (in which 1≦q≦10), C(CH 3 ) 2 , C(CF 3 ) 2  and C(═O)NH; 
         Ar 2  is a bivalent C 5 -C 24  arylene group or a bivalent C 5 -C 24  heterocyclic ring, which is substituted or unsubstituted with at least one substituent selected from the group consisting of C 1 -C 10  alkyl, C 1 -C 10  alkoxy, C 1 -C 10  haloalkyl and C 1 -C 10  haloalkoxy, or two or more of which are fused together to form a condensation ring or covalently bonded to each other via a functional group selected from the group consisting of O, S, C(═O), CH(OH), S(═O) 2 , Si(CH 3 ) 2 , (CH 2 ) p  (in which 1≦p≦10), (CF 2 ) q  (in which 1≦q≦10), C(CH 3 ) 2 , C(CF 3 ) 2  and C(═O)NH; 
         Q is O, S, C(═O), CH(OH), S(═O) 2 , Si(CH 3 ) 2 , (CH 2 ) p  (in which 1≦p≦10), (CF 2 ) q  (in which 1≦q≦10), C(CH 3 ) 2 , C(CF 3 ) 2 , C(═O)NH, C(CH 3 )(CF 3 ), C 1 -C 6  alkyl-substituted phenyl or C 1 -C 6  haloalkyl-substituted phenyl in which Q is linked to opposite both phenyl rings in the position of m-m, m-p, p-m or p-p; 
         Y is —OH, —SH or —NH 2 ; 
         n is an integer from 20 to 200; 
         m is an integer from 10 to 400; and 
         l is an integer from 10 to 400. 
       
     
     
         2 . The dope solution composition according to  claim 1 , wherein Ar 1  is selected from the following compounds: 
       
         
           
           
               
               
           
         
         wherein X is O, S, C(═O), CH(OH), S(═O) 2 , Si(CH 3 ) 2 , (CH 2 ) p  (in which 1≦p≦10), (CF 2 ) q  (in which 1≦q≦10), C(CH 3 ) 2 , C(CF 3 ) 2 , or C(═O)NH; W is O, S or C(═O); and Z 1 , Z 2  and Z 3  are identical to or different from each other and are O, N or S. 
       
     
     
         3 . The dope solution composition according to  claim 1 , wherein Ar 1  is selected from the following compounds: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
       
     
     
         4 . The dope solution composition according to  claim 1 , wherein Ar 2  is selected from the following compounds: 
       
         
           
           
               
               
           
         
         wherein X is O, S, C(═O), CH(OH), S(═O) 2 , Si(CH 3 ) 2 , (CH 2 ) p  (in which 1≦p≦10), (CF 2 ) q  (in which 1≦q≦10), C(CH 3 ) 2 , C(CF 3 ) 2 , or C(═O)NH; W is O, S or C(═O); and Z 1 , Z 2  and Z 3  are identical to or different from each other and are O, N or S. 
       
     
     
         5 . The dope solution composition according to  claim 1 , wherein Ar 2  is selected from the following compounds: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
       
     
     
         6 . The dope solution composition according to  claim 1 , wherein Q is selected from the group consisting of CH 2 , C(CH 3 ) 2 , C(CF 3 ) 2 , O, S, S(═O) 2  and C(═O). 
     
     
         7 . The dope solution composition according to  claim 1 , wherein 
       
         
           
           
               
               
           
         
       
       and Q is C(CF 3 ) 2 . 
     
     
         8 . The dope solution composition according to  claim 1 , wherein the copolymerization ratio (m:l) of the copolymers of Formulae 5 to 8 is from 0.1:9.9 to 9.9:0.1. 
     
     
         9 . The dope solution composition according to  claim 1 , wherein the copolymers of polyamic acids represented by Formulae 1 to 4 are selected from those represented by Formulae 9 to 18 below: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         In Formulae 9 to 18, 
         Ar 1 , Q, Y, m and l are defined as above; and 
         Y′ is different from Y and is —OH, —SH or —NH 2 . 
       
     
     
         10 . The dope solution composition according to  claim 9 , wherein the copolymerization ratio (m:l) of the copolymers of Formulae 9 to 18 is from 0.1:9.9 to 9.9:0.1. 
     
     
         11 . The dope solution composition according to  claim 1 , wherein the dope solution composition comprises 5 to 45% by weight of the polymer for forming a hollow fiber, 25 to 94% by weight of the organic solvent and 0.5 to 40% by weight of the additive. 
     
     
         12 . The dope solution composition according to  claim 1 , wherein the organic solvent is selected from the group consisting of: alcohols including methanol, ethanol, 2-methyl-1-butanol and 2-methyl-2-butanol; ketones including γ-butyrolactone, cyclohexanone, 3-hexanone, 3-heptanone, 3-octanone, acetone and methyl ethyl ketone; tetrahydrofurane; dichloroethane; dimethyl sulfoxide; N-methyl-2-pyrrolidone; N,N-dimethylformamide; N,N-dimethylacetamide; and
 mixtures thereof.   
     
     
         13 . The dope solution composition according to  claim 1 , wherein the additive is selected from the group consisting of: water; alcohols including glycerol, ethylene glycol, propylene glycol and diethylene glycol; polymers including polyvinylalcohol, polyacrylic acid, polyacrylamide, polyethylene glycol, polypropylene glycol, chitosan, chitin, dextran and polyvinylpyrrolidone; and salts including lithium chloride, sodium chloride, calcium chloride, lithium acetate, sodium sulfate and sodium hydroxide and mixtures thereof. 
     
     
         14 . A method for preparing a hollow fiber comprising:
 (S1) spinning the dope solution composition according to  claim 1  to prepare a polyamic acid hollow fiber;   (S2) imidizing the polyamic acid hollow fiber to obtain a polyimide hollow fiber; and   (S3) thermal-treating the polyimide hollow fiber to induce intramolecular and intermolecular rearrangement and obtain a hollow fiber comprising one selected from polymers represented by the following Formulae 19 to 32 and copolymers thereof.   
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         In Formulae 19 to 32, 
         Ar 1  is a tetravalent C 5 -C 24  arylene group or a tetravalent C 5 -C 24  heterocyclic ring, which is substituted or unsubstituted with at least one substituent selected from the group consisting of C 1 -C 10  alkyl, C 1 -C 10  alkoxy, C 1 -C 10  haloalkyl and C 1 -C 10  haloalkoxy, or two or more of which are fused together to form a condensation ring or covalently bonded to each other via a functional group selected from the group consisting of O, S, C(═O), CH(OH), S(═O) 2 , Si(CH 3 ) 2 , (CH 2 ) p  (in which 1≦p≦10), (CF 2 ) q  (in which 1≦q≦10), C(CH 3 ) 2 , C(CF 3 ) 2  and C(═O)NH; 
         Ar 1 ′ and Ar 2  are identical to or different from each other and are each independently a bivalent C 5 -C 24  arylene group or a bivalent C 5 -C 24  heterocyclic ring, which is substituted or unsubstituted with at least one substituent selected from the group consisting of C 1 -C 10  alkyl, C 1 -C 10  alkoxy, C 1 -C 10  haloalkyl and C 1 -C 10  haloalkoxy, or two or more of which are fused together to form a condensation ring or covalently bonded to each other via a functional group selected from the group consisting of O, S, C(═O), CH(OH), S(═O) 2 , Si(CH 3 ) 2 , (CH 2 ) p  (in which 1≦p≦10), (CF 2 ) q  (in which 1≦q≦10), C(CH 3 ) 2 , C(CF 3 ) 2  and C(═O)NH; 
         Q is O, S, C(═O), CH(OH), S(═O) 2 , Si(CH 3 ) 2 , (CH 2 ) p  (in which 1≦p≦10), (CF 2 ) q  (in which 1≦q≦10), C(CH 3 ) 2 , C(CF 3 ) 2 , C(═O)NH, C(CH 3 )(CF 3 ), C 1 -C 6  alkyl-substituted phenyl or C 1 -C 6  haloalkyl-substituted phenyl in which Q is linked to opposite both phenyl rings in the position of m-m, m-p, p-m or p-p; 
         Y″ is —O or S; 
         n is an integer from 20 to 200; 
         m is an integer from 10 to 400; and 
         l is an integer from 10 to 400. 
       
     
     
         15 . The method according to  claim 14 , wherein in the step S1, the spinning is dry-jet-wet spinning or wet-spinning. 
     
     
         16 . The method according to  claim 14 , wherein in the step S2, the imidization is carried out under an inert atmosphere at 150 to 300° C. for 1 minute to 12 hours. 
     
     
         17 . The method according to  claim 14 , wherein the polyimide hollow fiber includes polyimides represented by Formulae 33 to 40 below: 
       
         
           
           
               
               
           
         
         In Formulae 33 to 40, Ar 1 , Ar 2 , Q, Y, n, m, and l are defined as above. 
       
     
     
         18 . The method according to  claim 14 , wherein in the step S3, the thermal treatment is carried out under an inert atmosphere at 350 to 500° C. for 1 minute to 12 hours. 
     
     
         19 . The method according to  claim 14 , wherein in the step S3, the thermal treatment is carried out under an inert atmosphere at 400 to 450° C. for 10 minutes to 2 hours. 
     
     
         20 . The method according to  claim 14 , wherein the method comprises:
 a1) preparing a polyamic acid dope solution composition according to  claim 1 ;   a2) bringing the dope solution composition into contact with an internal coagulant and spinning the composition in air, while coagulating an insidie of a hollow fiber, to form a polyamic acid hollow fiber;   a3) coagulating the hollow fiber in a coagulation bath;   a4) washing the hollow fiber with a cleaning solution, followed by drying;   a5) imidizing the hollow fiber to obtain a polyimide hollow fiber; and   a6) thermally treating the polyimide hollow fiber.   
     
     
         21 . The method according to  claim 20 , wherein the spinning is carried out at a spinning temperature of 5 to 120° C. and a spinning rate of 5 to 100 m/min. 
     
     
         22 . The method according to  claim 20 , wherein the coagulation bath has a temperature of 0 to 50° C. 
     
     
         23 . The method according to  claim 20 , wherein the internal coagulant has a flow rate of 1 to 10 ml/min. 
     
     
         24 . A hollow fiber comprising one selected from polymers represented by Formulae 19 to 32 and copolymers thereof: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         In Formulae 19 to 32, 
         Ar 1  is a tetravalent C 5 -C 24  arylene group or a tetravalent C 5 -C 24  heterocyclic ring, which is substituted or unsubstituted with at least one substituent selected from the group consisting of C 1 -C 10  alkyl, C 1 -C 10  alkoxy, C 1 -C 10  haloalkyl and C 1 -C 10  haloalkoxy, or two or more of which are fused together to form a condensation ring or covalently bonded to each other via a functional group selected from the group consisting of O, S, C(═O), CH(OH), S(═O) 2 , Si(CH 3 ) 2 , (CH 2 ) p  (in which 1≦p≦10), (CF 2 ) q  (in which 1≦q≦10), C(CH 3 ) 2 , C(CF 3 ) 2  and C(═O)NH; 
         Ar 1 ′ and Ar 2  are identical to or different from each other and are each independently a bivalent C 5 -C 24  arylene group or a bivalent C 5 -C 24  heterocyclic ring, which is substituted or unsubstituted with at least one substituent selected from the group consisting of C 1 -C 10  alkyl, C 1 -C 10  alkoxy, C 1 -C 10  haloalkyl and C 1 -C 10  haloalkoxy, or two or more of which are fused together to form a condensation ring or covalently bonded to each other via a functional group selected from the group consisting of O, S, C(═O), CH(OH), S(═O) 2 , Si(CH 3 ) 2 , (CH 2 ) p  (in which 1≦p≦10), (CF 2 ) q  (in which 1≦q≦10), C(CH 3 ) 2 , C(CF 3 ) 2  and C(═O)NH; 
         Q is O, S, C(═O), CH(OH), S(═O) 2 , Si(CH 3 ) 2 , (CH 2 ) p  (in which 1≦p≦10), (CF 2 ) q  (in which 1≦q≦10), C(CH 3 ) 2 , C(CF 3 ) 2 , C(═O)NH, C(CH 3 )(CF 3 ), C 1 -C 6  alkyl-substituted phenyl or C 1 -C 6  haloalkyl-substituted phenyl in which Q is linked to opposite both phenyl rings in the position of m-m, m-p, p-m or p-p; 
         Y″ is —O or S; 
         n is an integer from 20 to 200; 
         m is an integer from 10 to 400; and 
         l is an integer from 10 to 400. 
       
     
     
         25 . The hollow fiber according to  claim 24 , wherein Ar 1  is selected from the following compounds: 
       
         
           
           
               
               
           
         
         wherein X is O, S, C(═O), CH(OH), S(═O) 2 , Si(CH 3 ) 2 , (CH 2 ) p  (in which 1≦p≦10), (CF 2 ) q  (in which 1≦q≦10), C(CH 3 ) 2 , C(CF 3 ) 2 , or C(═O)NH; W is O, S or C(═O); and Z 1 , Z 2  and Z 3  are identical to or different from each other and are O, N or S. 
       
     
     
         26 . The hollow fiber according to  claim 24 , wherein Ar 1  is selected from the following compounds: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
       
     
     
         27 . The hollow fiber according to  claim 24 , wherein Ar 1 ′ and Ar 2  are selected from the following compounds: 
       
         
           
           
               
               
           
         
         wherein X is O, S, C(═O), CH(OH), S(═O) 2 , Si(CH 3 ) 2 , (CH 2 ) p  (in which 1≦p≦10), (CF 2 ) q  (in which 1≦q≦10), C(CH 3 ) 2 , C(CF 3 ) 2 , or C(═O)NH; W is O, S or C(═O); and Z 1 , Z 2  and Z 3  are identical to or different from each other and are O, N or S. 
       
     
     
         28 . The hollow fiber according to  claim 24 , wherein Ar 1 ′ and Ar 2  are selected from the following compounds: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
       
     
     
         29 . The hollow fiber according to  claim 24 , wherein Q is selected from the group consisting of CH 2 , C(CH 3 ) 2 , C(CF 3 ) 2 , O, S, S(═O) 2  and C(═O). 
     
     
         30 . The hollow fiber according to  claim 24 , wherein 
       
         
           
           
               
               
           
         
       
       and Q is C(CF 3 ) 2 . 
     
     
         31 . The hollow fiber according to  claim 24 , wherein the hollow fiber is used as a gas separation membrane for separation of mixed gas pair of H 2 /N 2 , H 2 /CH 4 , H 2 /O 2 , H 2 /CO 2 , O 2 /CO 2 , N 2 /CH 4 , O 2 /N 2 , CO 2 /CH 4  and CO 2 /N 2 . 
     
     
         32 . The hollow fiber according to  claim 24 , wherein the hollow fiber has O 2 /N 2  selectivity of 3 or higher and CO 2 /CH 4  selectivity of 20 or higher. 
     
     
         33 . The hollow fiber according to  claim 24 , wherein the hollow fiber has O 2 /N 2  selectivity of 3 to 30 and CO 2 /CH 4  selectivity of 20 to 100.