POSS-containing in-situ composite nanogel with magnetic responsiveness and method for preparing the same

Abstract

The present invention provides a POSS-containing in-situ composite nanogel with magnetic responsiveness and the method for preparing the same, wherein POSS-containing macromolecule capable of polymerizing and metal-coordination complexing is synthesized to complex with iron salt, Fe.sup.2+/Fe.sup.3+ salts are in-situ deposited via chemical coprecipitation, and crosslinking agent and initiator are added to induce polymerization so that POSS-containing nanogel ranges with magnetic responsiveness is obtained. The present invention is of professional design, feasible technique and simple operation, and prepared nanogel magnetic particles are well dispersed with excellent magnetic responsiveness, which possesses a good application prospect in medical diagnosis, sensor, catalyst carrier and biomaterial.

Claims

1. A POSS-containing in-situ composite nanogel with magnetic responsiveness, wherein the POSS-containing in-situ composite nanogel is derived from an amphiphilic macromolecule (POSS-MA-PEG-DPA), the amphiphilic macromolecule being polymerizable and capable of metal-coordination complex adsorption of iron salts; superparamagnetic Fe.sub.3O.sub.4 particles obtained by in-situ chemical coprecipitation of the ferrous/ferric iron salts; and a crosslinking agent added for inducing polymerization to obtain stable nanogel; wherein the size of POSS-containing nanogel ranges from 100 to 300 nm, and the Fe.sub.3O.sub.4 particles with a size of 5˜15 nm are uniformly dispersed on the polymer.

2. A method for preparing the POSS-containing in-situ composite nanogel with magnetic responsiveness of claim 1 including the steps of: dissolving POSS-MA-PEG-DPA in THF, adding the solution dropwise into deionized water under ultrasonic and rotary evaporating for removing THF to obtain POSS-MA-PEG-DPA aqueous solution A; adding iron salt solution containing Fe.sup.2+/Fe.sup.3+ dropwise into the solution A, stirring for 0.5 to 3 hours and then adding NaOH solution dropwise to obtain solution B; adding a crosslinking agent together with an initiator, heating up to 50˜70° C. and reacting for 2 to 12 hours to obtain the POSS-containing in-situ composite nanogel with magnetic responsiveness.

3. The method according to claim 2, wherein the concentration of POSS-MA-PEG-DPA in the solution A ranges from 0.1 to 2 mg/mL.

4. The method according to claim 2, wherein in the iron salt solution, the concentration of ferrous iron salt ranges from 0.5 μmol/L to 10 μmol/L, and the concentration of ferric iron salt ranges from 1.0 μmol/L to 20 μmol/L.

5. The method according to claim 2, wherein the crosslinking agent is N,N′-Methylene-bis-acrylamide with a dosage of 0.1-1 wt % of POSS-MA-PEG-DPA; the initiator is ammonium persulphate or potassium persulphate with a dosage of 0.1˜1.5 wt % of POSS-MA-PEG-DPA.

6. The method according to claim 2, wherein the structure formula of POSS-MA-PEG-DPA is as follows: ##STR00002## wherein R refers to organic corner group of POSS and n refers to degree of polymerization of polyethylene glycol (PEG), wherein the PEG has a molecular weight of 600˜4000; wherein the function corner group of POSS is aminopropyl group and the rest seven corner groups are isobutyl groups.

7. The method according to claim 2, wherein PEG has a molecular weight of 600-4000.

8. The method according to claim 2, wherein the method further includes steps of preparing the POSS-MA-PEG-DPA by: dissolving aminopropyl POSS, maleic anhydride (MA) and a polymerization inhibitor into toluene, reacting at 90° C. for 24 hours and then separating and purifying to get POSS-MA; dissolving POSS-MA, PEG, the polymerization inhibitor and a catalyst into toluene, reacting at 135° C. for 36 hours and then separating and purifying to get POSS-MA-PEG; dissolving POSS-MA-PEG, 2,6-Pyridinedicarboxylic acid (DPA), the polymerization inhibitor and the catalyst into 1,4-dioxane, reacting at 125° C. for 24 hours and then separating and purifying to get POSS-MA-PEG-DPA.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 illustrates TEM photo and high-resolution TEM photo of POSS-containing in-situ composite nanogel of the present invention;

(2) FIG. 2 illustrates SEM photo of POSS-containing in-situ composite nanogel of the present invention;

(3) FIG. 3 illustrates XRD spectra of POSS-containing in-situ composite nanogel of the present invention;

(4) FIG. 4 illustrates hysteresis loop diagram of POSS-containing in-situ composite nanogel of the present invention;

(5) FIG. 5 illustrates thermal gravimetric diagram of POSS-containing in-situ composite nanogel of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(6) The present invention will be further described with the drawings and the embodiments.

Embodiment 1

(7) (1) Preparation of POSS-MA-PEG-DPA Macromolecule

(8) 6 g POSS, 0.67 g maleic anhydride (MA), 0.034 g hydroquinone and 50 ml toluene are mixed together to react at 90° C. for 24 hours, and then the mixture is separated and purified to get POSS-MA; 1 g POSS-MA, 2.05 g PEG1000, 0.011 g p-toluenesulfonic acid, 0.0187 hydroquinone and 50 mL toluene are mixed together to react at 135° C. for 24 hours under nitrogen atmosphere, and then the mixture is separated and purified to get POSS-MA-PEG1000; 2 g POSS-MA-PEG1000, 0.078 g 2,6-Pyridinedicarboxylic acid (DPA), 0.0054 g p-toluenesulfonic acid, 0.0096 g hydroquinone and 50 mL 1,4-dioxane are mixed together to react at 125° C. for 24 hours, and then the mixture is separated and purified to get POSS-MA-PEG1000-DPA.

(9) (2) Preparation of POSS-Containing In-Situ Composite Nanogel

(10) 0.50 g POSS-MA-PEG1000-DPA is dissolved in 10 mL THF to obtain solution A; 250 μL solution A is added dropwise into 10 mL deionized water under ultrasonic and the mixture is rotary evaporated for removing THF to obtain POSS-MA-PEG1000-DPA aqueous solution.

(11) 2.73 g FeCl.sub.3.6H.sub.2O and 1.45 g FeSO.sub.4.7H.sub.2O are dissolved in 100 mL deionized water to get Fe.sup.2+/Fe.sup.3+ salt solution; 100 μL Fe.sup.2+/Fe.sup.3+ salt solution is added dropwise into previous POSS-MA-PEG1000-DPA aqueous solution and stirred for 1 hours, then 100 μL NaOH of 0.44 mol/L is added and stirred for another 1 hours; 0.012 g N,N′-methylene-bis-acrylamide, 0.009 g ammonium persulphate are added and the mixture is heated up to 60° C. for 6 hours to obtain the POSS-containing in-situ composite nanogel.

(12) The average particle size of the nanogel is 255.8 nm measured by DLS, and the saturation magnetic intensity of the nanogel is 32.9 emu/g measured by SQUID.

Embodiments 2 to 4

(13) The methods for preparing POSS-containing in-situ composite nanogel of embodiments 2 to 4 are similar to embodiment 1 expect molecular weight of PEG is changed to 600, 2000 and 4000 respectively, and the results present on sheet 1.

Embodiments 5 to 8

(14) The methods for preparing POSS-containing in-situ composite nanogel of embodiments 5 to 8 are similar to embodiment 1 expect dosage of Fe.sup.2+/Fe.sup.3+ salt solution is changed to 100 μL, 300 μL, 400 μL and 500 μL respectively, and the results present on sheet 2.

(15) Sheet 1

(16) TABLE-US-00001 particle size of saturation magnetic intensity of Embodiment nanogel (nm) nanogel (emu/g) 2 235.4 31.6 3 267.8 33.8 4 296.9 31.2

(17) Sheet 2

(18) TABLE-US-00002 particle size saturation magnetic of nanogel intensity of Embodiment (nm) nanogel (emu/g) 5 254.3 22.4 6 258.7 43.1 7 266.9 54.7 8 272..8 66.5

INDUSTRIAL APPLICABILITY

(19) The present invention is of professional design, feasible technique and simple operation. Prepared nanogel magnetic particles are well dispersed with excellent magnetic responsiveness.