Solvent-free production of porous polymer structures

1 . A method of manufacturing a porous polymer structure having a pore size of 1 to 5000 nm, comprising the steps of:

a) providing a powder mixture comprising:

1 to 90 wt. % of at least one of one or more polymers and oligomeric precursors thereof,

0.5 to 95 wt. % of at least one of salt nanoparticles and salt microparticles having primary particle sizes between 1 and 50,000 nm,

wherein at least part of one or both of said at least one of salt nanoparticles and salt microparticles is one or more solid acids,

and

wherein the ratio of polymer to particles is in the range of 3:1 to 1:10 by weight;

d) primary shaping said mixture to obtain a material; and

i) removing said at least one of salt nanoparticles and salt microparticles with a non-organic solvent to obtain a porous polymer structure.

2 . The method according to claim 1 , further comprising step

f) subjecting the material to at least one of a drying step and a cooling step.

3 . The method according to claim 1 , further comprising step

g) subjecting the material to at least one of further reshaping and further processing.

4 . The method according to claim 1 , further comprising step

h) subjecting the material to a polymerization or cross-linking step.

5 . The method according to claim 1 , wherein the primary shaping in step (d) is performed by extruding said mixture through a die to form porous polymer structures with a constant cross section.

6 . The method according to claim 1 , wherein the primary shaping in step (d) is performed by casting said mixture to form parts with a non-uniform cross section.

7 . The method according to claim 1 , wherein one or more of the method steps are performed continuously.

8 . The method according to claim 1 , further comprising step

e) coating a substrate with said mixture,

wherein said coating step (e) is selected from the group consisting of spraying and roll-to-roll processes.

9 . The method according to claim 8 , wherein

a) said substrate is made of polymer(s), rubber(s), metal(s), ceramic(s) and glass(es); and/or

b) wherein said substrate is a film, a woven or non-woven textile; and/or

c) wherein said substrate has a two-dimensional or a three-dimensional shape.

10 . The method according to claim 8 , further comprising removing the obtained porous polymer structure from said substrate.

11 . The method according to claim 1 , wherein a) one or both of said nanoparticles and microparticles are selected from the group consisting of oxides, carbonates, sulphates, halogenides, nitrates and phosphates; and/or

b) one or both of said at least one of salt nanoparticles and salt microparticles have a particle size of 1 to 50000 nm.

12 . The method according to claim 1 , wherein said solid acids is/are selected from the group consisting of at least one of

i) carboxylic acids; and/or

ii) sulfonic acids; and/or

iii) phosphonic acids; and/or

iv) pyrophosphoric acid; and/or

v) amino acids; and/or

vi) Lewis acids;

and derivatives thereof.

13 . The method according to claim 1 , wherein said at least one or more polymers is/are selected from the group consisting of at least one of

polysulfones, polyethersulfones, polycarbonates, polystyrenes, polyacrylates, polysiloxanes, polyarylates, polyurethanes, polyesters, polyethers, polyimides, polyamides, halogenated polyolefins, cellulose acetates, liquid crystal polymers, and polymers that can be cross-linked.

14 . The method according to claim 1 , wherein the method comprises an additional step

k) exposing an inner bulk material of the primary shaped mixture;

wherein step (k) is performed after step (d) and prior to step (i) and, if present, prior to any of a step e) coating a substrate with said mixture, a step f) subjecting the material to at least one of a drying step and a cooling step, a step g) subjecting the material to at least one of further reshaping and further processing, and a step h) subjecting the material to a polymerization or cross-linking step; or

wherein step (k) is performed after step (d) and, if present, after any of a step e) coating a substrate with said mixture, a step f) subjecting the material to at least one of a drying step and a cooling step, a step g) subjecting the material to at least one of further reshaping and further processing, and a step h) subjecting the material to a polymerization or cross-linking step, and prior to step (i).

15 . A method of manufacturing a porous polymer structure having a pore size of 1 to 5000 nm, comprising the steps of:

a) providing a powder mixture comprising:

1 to 90 wt. % of at least one of one or more polymers and oligomeric precursors thereof,

0.5 to 95 wt. % of at least one of salt nanoparticles and salt microparticles having primary particle sizes between 1 and 50,000 nm,

wherein at least part of one or both of said at least one of salt nanoparticles and salt microparticles is one or more solid acids,

and

wherein the ratio of polymer to particles is in the range of 3:1 to 1:10 by weight;

d) primary shaping said mixture to obtain a material, wherein the primary shaping is performed by extruding said mixture through a die to form porous polymer structures with a constant cross-section or the primary shaping is performed by casting said mixture to form parts with a non-uniform cross-section; and

i) removing said at least one of salt nanoparticles and salt microparticles with a non-organic solvent to obtain a porous polymer structure.

16 . A method of manufacturing a porous polymer structure having a pore size of 1 to 5000 nm, comprising the steps of:

a) providing a powder mixture comprising:

1 to 90 wt. % of at least one of one or more polymers and oligomeric precursors thereof,

0.5 to 95 wt. % of at least one of salt nanoparticles and salt microparticles having primary particle sizes between 1 and 50,000 nm,

wherein 40 to 85 wt. % of said at least one of salt nanoparticles and salt microparticles is one or more solid acids,

and

wherein the ratio of polymer to particles is in the range of 3:1 to 1:10 by weight;

d) primary shaping said mixture to obtain a material; and

i) removing said at least one of salt nanoparticles and salt microparticles with a non-organic solvent to obtain a porous polymer structure.