阅读说明：本技术 一种多孔聚季磷型离子液材料及其制备方法 (Porous polyquaternary phosphorus type ionic liquid material and preparation method thereof ) 是由 崔佳 孟祥举 胡长禄 龚奇菡 韩晓琳 李知春 吕雉 张上 张鹏 潘晖华 桂鹏 于 2020-06-19 设计创作，主要内容包括：本发明涉及一种多孔聚季磷型离子液材料的制备方法,包括以下步骤：(1)将三(4-乙烯基苯基)膦、卤化氢与羟基苯甲醇进行季膦化反应,将其转化为阴离子为卤离子的季膦型离子液体,且,三(4-乙烯基苯基)膦∶溴化氢∶羟基苯甲醇的摩尔比为1:15～40:1.5～2.0；(2)将步骤(1)制得的离子液体作为基本骨架材料溶于致孔溶剂,加入聚合引发剂偶氮二异丁腈,搅拌聚合,蒸馏回收溶剂后,得到多孔聚季磷型离子液材料,且,基本骨架材料∶致孔溶剂∶聚合引发剂的质量比为1∶5～50∶0.005～0.015。(The invention relates to a preparation method of a porous polyquaternary phosphorus type ionic liquid material, which comprises the following steps: (1) carrying out a quaternary phosphonation reaction on tris (4-vinylphenyl) phosphine, hydrogen halide and hydroxybenzyl alcohol, and converting the quaternary phosphonation reaction into a quaternary phosphine type ionic liquid with halide ions as anions, wherein the molar ratio of the tris (4-vinylphenyl) phosphine to the hydrogen bromide to the hydroxybenzyl alcohol is 1: 15-40: 1.5-2.0; (2) and (2) dissolving the ionic liquid prepared in the step (1) as a basic framework material in a pore-forming solvent, adding a polymerization initiator azodiisobutyronitrile, stirring for polymerization, and distilling to recover the solvent to obtain the porous polyquaternary phosphorus type ionic liquid material, wherein the mass ratio of the basic framework material to the pore-forming solvent to the polymerization initiator is 1: 5-50: 0.005-0.015.)

1. The preparation method of the porous polyquaternary phosphorus ionic liquid material is characterized by comprising the following steps:

(1) reacting tris (4-vinylphenyl) phosphine with hydrogen halide to obtain tris (4-vinylphenyl) phosphine hydrogen halide, then carrying out quaternary phosphonation reaction on the tris (4-vinylphenyl) phosphine hydrogen halide and hydroxybenzyl alcohol, and converting the tris (4-vinylphenyl) phosphine hydrogen halide into quaternary phosphine type ionic liquid with halide ions, wherein the molar ratio of the tris (4-vinylphenyl) phosphine to the hydrogen bromide to the hydroxybenzyl alcohol is 1: 15-40: 1.5-2.0;

(2) and (2) dissolving the ionic liquid prepared in the step (1) as a basic framework material in a pore-forming solvent, adding a polymerization initiator azodiisobutyronitrile, stirring for polymerization, and distilling to recover the solvent to obtain the porous polyquaternary phosphorus type ionic liquid material, wherein the mass ratio of the basic framework material to the pore-forming solvent to the polymerization initiator is 1: 5-50: 0.005-0.015.

2. The process according to claim 1, wherein the tris (4-vinylphenyl) phosphine is reacted with a hydrogen halide under the conditions: stirring for 15-120 minutes at 25-30 ℃, and then stirring for 10-20 minutes at 50-100 ℃.

3. The method according to claim 1, wherein in the step (1), after the reaction of tris (4-vinylphenyl) phosphine with hydrogen halide is completed, the solvent in the obtained mixed solution is evaporated to dryness, the remaining solid is washed with trichloromethane and with ethyl acetate to remove unreacted raw materials, and the dried solid is vacuum-dried to obtain the tris (4-vinylphenyl) phosphine hydrogen halide.

4. The preparation method according to claim 3, wherein the mass ratio of the trichloromethane to the ethyl acetate is as follows: 1:3 to 3: 1.

5. The method according to claim 1, wherein the step of the quaternary phosphonation reaction is: and (3) refluxing the tris (4-vinylphenyl) phosphine hydrogen bromide salt and the hydroxybenzyl alcohol in anhydrous acetonitrile, cooling, filtering and spin-drying to obtain the quaternary phosphorus type ionic liquid.

6. The method according to claim 1, wherein the hydrogen halide is hydrogen bromide, hydrogen chloride or hydrogen fluoride.

7. The method according to claim 1, wherein the hydroxybenzyl alcohol is 2-hydroxybenzyl alcohol, 3-hydroxybenzyl alcohol or 4-hydroxybenzyl alcohol.

8. The production method according to claim 1, wherein in the step (2), the conditions of the agitation polymerization are: stirring and polymerizing for 6-48 hours at 60-240 ℃.

9. The method as claimed in claim 1, wherein in the step (2), the distillation temperature is 110-130 ℃; the time of the reflux reaction is 1-5 hours.

10. The method according to claim 1, wherein the pore-forming solvent is tetrahydrofuran, N-dimethylformamide, or N-methylpyrrolidone.

11. A porous polyquaternary phosphorus type ionic liquid material prepared by the preparation method of any one of claims 1 to 10, wherein the porous polyquaternary phosphorus type ionic liquid material has a pore diameter of 0.4 to 50nm and a specific surface area of 350 to 450m²/g。

Technical Field

The invention belongs to the field of porous organic materials, and particularly relates to a porous polyquaternary phosphorus type ionic liquid material and a preparation method thereof.

Background

Compared with porous inorganic materials, porous polymers have wide applications in catalysis, adsorption, ion exchange, separation and the like due to the characteristics of small density, special mechanical properties and large selectivity of the monomer which can be modulated according to requirements. (a) N.b.mckeown, p.m.budd, chem.soc.rev.2006,35,675; b) kaur, j.t.hupp, s.t.nguyen, ACS catal.2011,1,819; c) y.zhang, s.n.ridean, chem.soc.rev.2012,41,2083; d) thomas, angelw, chem, int, ed, 2010,49,8328; e) xie, c.wang, k.e.dekrafft, w.lin, j.am.chem.soc.2011,133, 2056; f) -y.ding, j.gao, q.wang, y.zhang, w.g.song, c.y.su, w.wang, j.am.chem.soc.2011,133, 19816; g) p.zhang, z.weng, j.guo, c.wang, chem.mater.2011,23,5243; h) x.zhu, c.tian, s.m.mahurin, s. -h.chai, c.wang, s.brown, g.m.veith, h.luo, h.liu, s.dai, j.am.chem.soc.2012,134, 10478; i) g.cheng, t.hasell, a.trewin, d.j.adams, a.i.cooper, angelw.Chem.int.ed.2012,51,12727; j) kulun, m.antonietti, a.thomas, angelw.chem.int.ed.2008, 47,3450; k) guo, t.ben, z.bin, g.m.veith, x. -g.sun, s.qiu, s.dai, chem.commun.2013,49,4905; l) c.zhang, j. -j.wang, y.liu, h.ma, x. -l.yang, h. -b.xu, chem.eur.j.2013,19,5004; m) y.liang, r.fu, d.wu, ACS Nano 2013,7,1748.) ionic liquids are, on the other hand, widely used in catalysis, separation and purification and electrochemical studies due to their unique properties such as low vapor pressure, special solubility properties, composition variability. (a) Xiong, j.liu, y.wang, h.wang, r.wang, angelw.chem.int.ed.2012, 51,9114; b) b.lin, l.qiu, j.lu, f.yan, chem.mater.2010,22,6718; c) q.zhao, p.zhang, m.antonietti, j.yuan, j.am.chem.soc.2012,134, 11852; d) V.I are provided.C.hardacre, chem.rev.2007,107, 2615; e) m.a.p.martins, c.p.frizzo, d.n.moreira, n.zanattata, h.g.bonacorso, chem.rev.2008,108, 2015; f) t.l.great, c.j.drummond, chem.rev.2008,108, 206; g) yuan, s.soll, m.drechsler, a.h.e.muller, m.antonietti, j.am.chem.soc.2011,133, 17556; h) r.girrnoth, angelw.chem.int.ed.2010, 49,2834.) porous polyionic liquid polymers can combine the respective advantages of porous polymers and ionic liquids to arouse the researchers' wide interest, for example, have a wider electrochemical window in electrochemical applications and are more convenient to separate from a reaction system and recycle in catalytic applications. (a) M.armand, f.endres, d.r.macfarlane, h.ohno, b.scrosati, nat.mater.2009,8,621; b) j.h.cho, j.lee, y.xai, b.kim, y.he, m.j.renn, t.p.lodge, c.d.frisbie, nat.mater.2008,7, 900; c) liu, l.wang, q.sun, l.zhu, x.meng, f.s.xiao, j.am.chem.soc.2012,134, 16948; d) y.xie, z.zhang, t.jiang, j.he, b.han, t.wu, k.ding, angelw.chem.int.ed.2007, 46,7255.) but the existing methods for preparing porous polyion liquids are very cumbersome and cannot be used for experimental large-scale production applications, for example, the ionic liquids are grafted on the original porous polymers after grafting, and porous polyion liquids (a) a.wilke, j.weber, macro mol.rapid commu.2012, 33,785 are obtained by melting silicon through using nano silicon spheres as a hard template; b) q.li, j.f.quinn, f.caroso, adv.mater.2005,17,2058; c) wang, a.m.yu, f.caroso, Angew.Chem.Int.Ed.2005,44,2888；d)J.L.Lutkenhaus,K.McEnnis,P.T.Hammond,Macromolecules 2008,41,6047；d)J.Hiller,J.D.Mendelsohn,M.F.Rubner,Nat.Mater.2002,1,59)。

Chinese patent 'preparation method of porous polyquaternary phosphonium ionic liquid (CN 201310410837)' provides a method for preparing porous polyquaternary phosphonium ionic liquid material, but in the method, four substituent groups are benzene, and a substituent functional group is lacked, so that the catalysis or other performances of the ionic liquid are seriously restricted.

Thus, it remains a challenge how to synthesize porous functional polyionic liquid materials that are simple and suitable for large-scale production.

Disclosure of Invention

In view of the above, the present invention aims to overcome the disadvantages of the prior art, such as the insufficient functionality of four phenyl groups in the prepared material, replace one of four vinyl benzenes with hydroxybenzyl alcohol, and realize functional modulation by adjusting the positions of hydroxyl groups (2-hydroxybenzyl alcohol, 3-hydroxybenzyl alcohol, and 4-hydroxybenzyl alcohol). Therefore, the invention provides a porous polyquaternary phosphorus type ionic liquid material and a preparation method thereof.

Therefore, the invention provides a preparation method of a porous polyquaternary phosphorus type ionic liquid material, which comprises the following steps:

(1) reacting tris (4-vinylphenyl) phosphine with hydrogen halide, then carrying out a quaternary phosphonation reaction with hydroxybenzyl alcohol, and converting the tris (4-vinylphenyl) phosphine into a quaternary phosphine type ionic liquid with bromide ions as anions, wherein the molar ratio of tris (4-vinylphenyl) phosphine to hydrogen bromide to hydroxybenzyl alcohol is 1: 15-40: 1.5-2.0;

(2) and (2) dissolving the ionic liquid prepared in the step (1) as a basic framework material in a pore-forming solvent, adding a polymerization initiator azodiisobutyronitrile, stirring for polymerization, and distilling to recover the solvent to obtain the porous polyquaternary phosphorus type ionic liquid material, wherein the mass ratio of the basic framework material to the pore-forming solvent to the polymerization initiator is 1: 5-50: 0.005-0.015.

In the preparation method of the present invention, the conditions of the quaternary phosphonation reaction are preferably: stirring for 15-120 minutes at 20-30 ℃, and then stirring for 10-20 minutes at 50-100 ℃.

In the preparation method according to the present invention, in the step (1), after the reaction of tris (4-vinylphenyl) phosphine with hydrogen halide is completed, the solvent in the obtained mixed solution is evaporated to dryness, and the remaining solid is washed with trichloromethane and ethyl acetate to remove unreacted raw materials, and then vacuum-dried to obtain the tris (4-vinylphenyl) phosphine hydrogen halide.

In the preparation method of the invention, preferably, the mass ratio of the trichloromethane to the ethyl acetate is as follows: 1:3 to 3: 1.

In the preparation method of the present invention, it is preferable that the quaternary phosphonation reaction comprises the steps of: and (3) refluxing the tris (4-vinylphenyl) phosphine hydrogen bromide salt and the hydroxybenzyl alcohol in anhydrous acetonitrile, cooling, filtering and spin-drying to obtain the quaternary phosphorus type ionic liquid.

In the production method of the present invention, it is preferable that the hydrogen halide is hydrogen bromide, hydrogen chloride or hydrogen fluoride.

In the production method of the present invention, it is preferable that the hydroxybenzyl alcohol is preferably 2-hydroxybenzyl alcohol, 3-hydroxybenzyl alcohol or 4-hydroxybenzyl alcohol.

In the preparation method of the present invention, in the step (2), preferably, the conditions of the stirring polymerization are: stirring and polymerizing for 6-48 hours at 60-240 ℃.

In the preparation method of the present invention, in the step (2), preferably, the distillation temperature is 110-; the time of the reflux reaction is 1-5 hours.

In the preparation method of the present invention, preferably, the pore-forming solvent is tetrahydrofuran, N-dimethylformamide or N-methylpyrrolidone.

The invention also provides a porous polyquaternary phosphorus type ionic liquid material which is prepared by the preparation method, wherein the pore diameter of the porous polyquaternary phosphorus type ionic liquid material is 0.4-50 nm, and the specific surface area is 350-450 m²/g。

The preparation method of the porous polyquaternary phosphorus type ionic liquid material provided by the invention comprises the following specific steps:

s1, reacting tris (4-vinylphenyl) phosphine with hydrogen bromide, and then carrying out a quaternary phosphonation reaction with hydroxybenzyl alcohol to convert the tris (4-vinylphenyl) phosphine into a quaternary phosphonium salt ionic liquid with bromide ions as anions. Wherein the molar ratio of the tri (4-vinylphenyl) phosphine to the hydrogen bromide to the hydroxybenzyl alcohol is 1: 15-40: 1.5-2.0.

S2, dissolving the functionalized quaternary phosphonium ionic liquid of the basic framework material in a pore-forming solvent, and adding a polymerization initiator azobisisobutyronitrile; stirring and polymerizing for 6-48 hours at 60-240 ℃, and distilling and recovering the solvent at 120 ℃ to obtain the porous polyquaternary phosphorus ionic liquid material; wherein the mass ratio of the basic framework material, the pore-forming solvent and the polymerization initiator is 1: 5-50: 0.005-0.015.

Step S1 can also be described in detail as including the following steps:

s11, adding the tri (4-vinyl phenyl) phosphine into the hydrogen bromide solution, stirring for 15-120 minutes at room temperature, and then stirring for 10-20 minutes at 50-100 ℃. After the reaction is finished, the solvent is dried by a rotary evaporator, unreacted raw materials are washed away by chloroform and solid obtained by washing with ethyl acetate, and the solid is dried in vacuum at room temperature to obtain the tris (4-vinylphenyl) phosphine hydrogen bromide.

S12, carrying out reflux reaction on tris (4-vinylphenyl) phosphine hydrogen bromide and hydroxybenzyl alcohol in anhydrous acetonitrile for 1-5 hours, cooling, filtering, and spin-drying to obtain the functionalized quaternary phosphorus type ionic liquid.

Compared with the prior art, the invention has the beneficial effects that:

the invention prepares the functionalized quaternary phosphorus type ionic liquid monomer by reacting tri (4-vinyl phenyl) phosphine with hydrogen bromide and then carrying out quaternary phosphonation reaction with hydroxybenzyl alcohol; and then carrying out one-step solvent thermal polymerization on the functionalized quaternary phosphorus type ionic liquid monomer to obtain the porous polyquaternary phosphorus type ionic liquid polymer.

The triphenylphosphine ionic liquid polymer synthesized by the method has the following characteristics: different vinyl functionalized ionic liquid monomers can be adjusted and different porous polyionic liquids can be obtained simply by introducing different hydroxybenzyl alcohols.

Drawings

FIG. 1 shows the preparation of monomers obtained in example 1 of the present invention¹H NMR chart;

FIG. 2 shows the preparation of monomers obtained in example 1 of the present invention³¹P NMR chart;

FIG. 3 shows the preparation of monomers according to example 1 of the invention¹³C NMR chart;

FIG. 4 shows the preparation of monomers obtained in example 2 of the present invention¹H NMR chart;

FIG. 5 shows the preparation of monomers obtained in example 2 of the present invention³¹P NMR chart;

FIG. 6 shows the preparation of monomers obtained in example 2 of the present invention¹³C NMR chart;

FIG. 7 shows the preparation of monomers according to example 3 of the present invention¹H NMR chart;

FIG. 8 shows the preparation of monomers according to example 3 of the present invention³¹P NMR chart;

FIG. 9 shows the preparation of monomers according to example 3 of the present invention¹³C NMR chart;

FIG. 10a is a drawing of a polymer made in example 4 of the present invention¹³A C MAS NMR chart;

FIG. 11 is a drawing showing a polymer obtained in example 4 of the present invention³¹P MAS NMR chart;

FIG. 12a is N of a polymer obtained in example 4 of the present invention₂Adsorption isotherms;

FIG. 13a is a TEM image of a polymer prepared in example 4 of the present invention;

FIG. 14a is a SEM photograph of a polymer prepared in example 4 of the present invention;

FIG. 10b is a photograph of a polymer obtained in example 5 of the present invention¹³A C MAS NMR chart;

FIG. 12b shows N for the polymer obtained in example 5 of the present invention₂Adsorption isotherms;

FIG. 13b is a TEM image of the polymer prepared in example 5 of the present invention;

FIG. 14b is a SEM photograph of a polymer prepared in example 5 of the present invention;

FIG. 10c is a photograph of a photograph obtained in example 6 of the present inventionOf (2) a polymer¹³A C MAS NMR chart;

FIG. 12c shows N for the polymer prepared in example 6 of the present invention₂Adsorption isotherms;

FIG. 13c is a TEM image of the polymer prepared in example 6 of the present invention;

FIG. 14c is a SEM photograph of a polymer prepared in example 6 of the present invention.

Detailed Description

The following examples illustrate the invention in detail: the present example is carried out on the premise of the technical scheme of the present invention, and detailed embodiments and processes are given, but the scope of the present invention is not limited to the following examples, and the experimental methods without specific conditions noted in the following examples are generally performed according to conventional conditions.

The invention prepares the functionalized quaternary phosphorus type ionic liquid monomer by reacting tri (4-vinyl phenyl) phosphine with hydrogen bromide and then carrying out quaternary phosphonation reaction with hydroxybenzyl alcohol; and then carrying out one-step solvent thermal polymerization on the functionalized quaternary phosphorus type ionic liquid monomer to obtain the porous polyquaternary phosphorus type ionic liquid polymer.

Example 1

Tris (4-vinylphenyl) phosphine (3mmol) was added portionwise to hydrobromic acid (45mmol) and stirred at room temperature for 120 min and then at 50 ℃ for 20 min. After cooling, chloroform (20mL) was added, dried and then spun dry, the solid was washed with ethyl acetate and dried under vacuum to give tris (4-vinylphenyl) phosphine hydrogen bromide.

Dissolving tris (4-vinylphenyl) phosphine hydrogen bromide (1.2mmol) and 2-hydroxybenzyl alcohol (1.8mmol) in anhydrous acetonitrile (10mL) under nitrogen atmosphere, refluxing and reacting for 1 hour, cooling, filtering, spin-drying, filtering and draining to obtain the 2-hydroxybenzyl-tris (4-vinylphenyl) phosphine bromide monomer.

For construction of single bodies¹HNMR (FIG. 1),³¹PNMR (FIG. 2) and¹³CNMR (fig. 3).

Example 2

Tris (4-vinylphenyl) phosphine (3mmol) was added portionwise to hydrobromic acid (120mmol) and stirred at room temperature for 15 minutes and then at 100 ℃ for 10 minutes. After cooling, chloroform (20mL) was added, dried and then spun dry, the solid was washed with ethyl acetate and dried under vacuum to give tris (4-vinylphenyl) phosphine hydrogen bromide.

Dissolving tris (4-vinylphenyl) phosphine hydrogen bromide (1.2mmol) and 3-hydroxybenzyl alcohol (2.4mmol) in anhydrous acetonitrile (10mL) under nitrogen atmosphere, refluxing for 3 hours, cooling, filtering, spin-drying, filtering and draining to obtain the 3-hydroxybenzyl-tris (4-vinylphenyl) phosphine bromide monomer.

For construction of single bodies¹HNMR (FIG. 4),³¹PNMR (FIG. 5) and¹³CNMR (fig. 6).

Example 3

Tris (4-vinylphenyl) phosphine (3mmol) was added portionwise to hydrobromic acid (45mmol) and stirred at room temperature for 120 min and then at 70 ℃ for 15 min. After cooling, chloroform (20mL) was added, dried and then spun dry, the solid was washed with ethyl acetate and dried under vacuum to give tris (4-vinylphenyl) phosphine hydrogen bromide.

Dissolving tris (4-vinylphenyl) phosphine hydrogen bromide (1.2mmol) and 2-hydroxybenzyl alcohol (1.8mmol) in anhydrous acetonitrile (10mL) under nitrogen atmosphere, refluxing for 5 hours, cooling, filtering, spin-drying, filtering and draining to obtain 4-hydroxybenzyl-tris (4-vinylphenyl) phosphine bromide.

For construction of single bodies¹HNMR (FIG. 7),³¹PNMR (FIG. 8) and¹³CNMR (fig. 9).

Example 4

2-hydroxybenzyl-tris (4-vinylphenyl) phosphine bromide monomer (1g) obtained in example 1 was dissolved in N, N-dimethylformamide (50g), azobisisobutyronitrile (15mg) was added, and after stirring for 30 minutes under nitrogen, the mixture was transferred to a reaction vessel and placed in an oven at 60 ℃ for reaction for 48 hours. Then, the polymer is washed by absolute ethyl alcohol and dried in vacuum to obtain white polymer, namely the target product.

Of the polymer¹³C NMR and³¹the P NMR patterns are shown in FIGS. 10a and 11, respectively. From FIG. 10a, it can be seen that a strong peak at 42.5ppm on the solid carbon nuclear magnetism of the polymer in addition to the characteristic peak of triphenylphosphine indicates that the vinyl group was successfully polymerized.As can be seen from FIG. 11³¹The PNMR diagram shows that the P-nuclear magnetic chemical shift of the polymer and the chemical shift of the monomer are almost the same, indicating that the valence state of the phosphine has not changed during the polymerization. N is a radical of₂The adsorption results are shown in FIG. 12a, and the specific surface area of the obtained polymer is 450m²About/g, pore size distribution is 0.6-20 nm. The results of scanning electron microscopy (fig. 13a) and of projection electron microscopy (fig. 14a) demonstrate the porosity of the obtained polymer.

Example 5

3-hydroxybenzyl-tris (4-vinylphenyl) phosphine bromide monomer (1g) from example 2 was dissolved in N-methylpyrrolidone (5g), azobisisobutyronitrile (5mg) was added, and after stirring for 30 minutes under nitrogen, the mixture was transferred to a reaction vessel and placed in an oven at 240 ℃ for reaction for 6 hours. Then, the polymer is washed by absolute ethyl alcohol and dried in vacuum to obtain white polymer, namely the target product.

Of the polymer¹³C NMR As shown in FIG. 10b, it can be seen that a strong peak at 42.8ppm on the solid carbon nuclear magnetic resonance of the polymer in addition to the characteristic peak of triphenylphosphine indicates that the vinyl group was successfully polymerized. N is a radical of₂The adsorption results showed that the specific surface area of the obtained polymer was 400m²Around/g (FIG. 12b), the pore size distribution is between 0.4 and 15 nm. The results of scanning electron microscopy (fig. 13b) and of projection electron microscopy (fig. 14b) demonstrate the porosity of the obtained polymer.

Example 6

4-hydroxybenzyl-tris (4-vinylphenyl) phosphine bromide (1g) monomer from example 3 was dissolved in tetrahydrofuran (25g), azobisisobutyronitrile (12mg) was added, and after stirring for 30 minutes under nitrogen, the mixture was transferred to a reaction vessel and placed in an oven at 100 ℃ for reaction for 24 hours. Then, the polymer is washed by absolute ethyl alcohol and dried in vacuum to obtain white polymer, namely the target product.

Of the polymer¹³C NMR chart As shown in FIG. 10C, it can be seen that a strong peak at 41.9ppm on the solid carbon nuclear magnetic spectrum of the polymer in addition to the characteristic peak of triphenylphosphine indicates that the vinyl group was successfully polymerized. N is a radical of₂The adsorption result shows that the specific surface area of the obtained polymer is 350m²About/g(FIG. 12c), pore size distribution was 0.6-50 nm. The results of scanning electron microscopy (fig. 13c) and projection electron microscopy (fig. 14c) demonstrate the porosity of the resulting polymerization.

The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is therefore intended that all such changes and modifications as fall within the true spirit and scope of the invention be considered as within the following claims.