CN101775148A

CN101775148A - Preparation method of microgel composite hydrogel

Info

Publication number: CN101775148A
Application number: CN200910255805A
Authority: CN
Inventors: 赵芳; 秦绪平
Original assignee: Shandong University
Current assignee: Shandong University
Priority date: 2009-12-30
Filing date: 2009-12-30
Publication date: 2010-07-14
Anticipated expiration: 2029-12-30
Also published as: CN101775148B

Abstract

The invention belongs to the technical field of polymer, and relates to a preparation method of microgel composite hydrogel, which comprises the following steps: preparing solution containing N-hydroxymethyl, preparing dispersion solution, preparing prepolymerization solution, polymerization and heating and crosslink at high temperature. Acrylamide is adopted as a main monomer, N-methylol acrylamide is used as a functional monomer, the prepared microgel dispersion solution containing the N-hydroxymethl is adopted as a potential crosslink agent, and then the microgel composite hydrogel is prepared with a method of first polymerization and later high-temperature processing and crosslink. The method is free from adopting chemical modifier to obtaining the microgel containing the potential crosslink point, so the preparation process of the microgel composiste hydrogel is simpler, and the mechanical performance of the prepared hydrogel is excellent.

Description

A kind of preparation method of microgel composite hydrogel

Technical field:

The invention belongs to technical field of macromolecules, relate in particular to a kind of preparation method of microgel composite hydrogel.

Background technology:

Hydrogel is a kind of functional high molecule material with three-dimensional net structure, can water absorption and swelling but water insoluble, have good water retention property and biocompatibility simultaneously, and twenty or thirty year is the focus of a research always recently.Can be widely used in various fields such as medicine, medical treatment, health care, building, agricultural gardening water-efficient irrigation, soil improvement, petrochemical complex, sewage disposal and organizational project.The traditional water gel is because bad mechanical strength, and limited its application greatly.The traditional water gel is to be prepared from by small molecules chemical cross-linking agent (as N, the two propyl group alkene acid amides of N '-methylene).Because the chaotic distribution of cross-linking set in system causes chain link different in size, the stress difference that every chain be can bear, stress concentrates on short chain and at first fracture easily, cause breaking of whole hydrogel then, thereby the overall mechanical properties of hydrogel is poor.

In recent years, the synthetic method of several high intensity hydrogel intensity has appearred: topological hydrogel, dual network water of constitution gel, composite aquogel.Compare with other two kinds of hydrogels, composite aquogel is because the advantage on its preparation method, caused extensive concern in recent years,, adopted the macromolecular microspheres composite aquogel of hydrophobicity macromolecular microspheres as initiator and linking agent as adopting the Nanometer composite hydrogel of clay as linking agent.But these two kinds of composite aquogels clay and hydrophobicity macromolecular microspheres in the preparation all belong to the weighting material that is different from the hydrogel body, and whole hydrogel is not the material of component homogeneous.When improving its hydrogel mechanical property, cause other performance decrease of hydrogel easily, as cmot, temperature sensitivity etc.

On Colloid Polym Sci (2009) 287:621-625 paper, disclose and adopted the reactive micro-gel that contains two keys to prepare microgel composite hydrogel as linking agent, this hydrogel has the structure of two levels, at first, microgel inside has network structure; Secondly, polymer chain links together by microgel, and this layer similar is in the clay composite aquogel; This hydrogel has excellent mechanical property.The principal monomer for preparing microgel and hydrogel simultaneously is identical, do not need to introduce other added ingredients, thereby making whole hydrogel is the material of component homogeneous, can not produce other performance decrease problem that causes owing to weighting material when improving its mechanical property.But when adopting double bond containing microgel to prepare microgel composite hydrogel, need at first that the method by chemical modification prepares double bond containing microgel on the basis of reactive micro-gel, make whole preparation process very complicated.

Summary of the invention:

The objective of the invention is to overcome above-mentioned the deficiencies in the prior art, the preparation method of the simple microgel composite hydrogel of a kind of technology is provided, when improving its mechanical property, can not produce because other performance decrease problem that weighting material causes.

The present invention realizes in the following manner:

The preparation method of microgel composite hydrogel comprises the steps:

The first step, preparation contains the microgel emulsion of N-methylol

Adopt emulsion polymerization, with driving oxygen under the nitrogen normal temperature after 20 minutes, the initiation reaction preparation contains the microgel emulsion of N-methylol, and its component and mass percent are:

Hexanaphthene: 40-45%

Acrylamide: 16-23%

2-acrylamido-2-methyl propane sulfonic acid (AMPS) or vinylformic acid: 1-7%

N hydroxymethyl acrylamide: 2-7%

N, N '-methylene-bisacrylamide: 0.005-0.10%

OP-10：1-3％

SP20 or SP80:3-9%

Water: 35-41%

Ammonium persulphate or Potassium Persulphate: 0.002-0.02%

Sodium bisulfite: 0.002-0.02%

Second step, the preparation dispersion liquid

To be scattered in again after the microgel emulsion drying in the water, the component of dispersion liquid and mass percentage content are:

Microgel: 3-4%

Water: 96-97%

Here the microgel quality of indication is meant water-free dried microgel quality;

The 3rd step, preparation pre-polymerization liquid

Acrylamide, 2-acrylamido-2-methyl propane sulfonic acid or vinylformic acid, dispersion liquid, water are mixed acquisition pre-polymerization liquid, and its component and mass percent are:

Acrylamide: 20-25%

2-acrylamido-2-methyl propane sulfonic acid or vinylformic acid: 2-5%

Dispersion liquid: 5-15%

Water: 60-70%

The 4th step, polymerization

Pre-polymerization liquid was driven oxygen more than 30 minutes, add the sodium bisulfite of 0.002-0.04% ammonium persulphate or Potassium Persulphate and 0.002-0.04%, normal temperature causes radical polymerization more than 3 hours down, obtains base polymer;

The 5th step, high-temperature heating treatment

With base polymer at 70-99 ℃ of heat treated 1.5-5 hour.

Concrete preparation technology can be summarized as:

The preparation contain the N-methylol emulsion → preparation dispersion liquid → preparation pre-polymerization liquid → polymerization → heat is crosslinked

The present invention adopts acrylamide as principal monomer, N hydroxymethyl acrylamide is as function monomer, the microgel dispersion that contains the N-methylol that adopts preparation is as potential cross-linking agent, adopt first polymerization then, the crosslinked method of back pyroprocessing is prepared microgel composite hydrogel, this method does not need to adopt chemical modification to obtain to contain the microgel of potential cross-linking set, makes the preparation technology of whole microgel composite hydrogel simpler, and the hydrogel mechanical property excellence of preparation.

Embodiment

Provide four most preferred embodiments of the present invention below.

Embodiment 1:

In the flask of 500ml, add 45 gram acrylamides, 4 gram AMPS, 4 gram N hydroxymethyl acrylamides, 0.05 gram is two the third, 56ml water, add 2.5 gram OP-10,7.5 gram SP80 after fully stirring, adds the 110ml hexanaphthene, add 0.005 gram ammonium persulphate and 0.01 after 20 minutes with nitrogen flooding oxygen and restrain sodium bisulfite, react acquisition in 3 hours and contain N-methylol microgel emulsion as initiator.Again be scattered in the 47 gram water after getting 8.5 gram emulsion dryings.Get 10 gram dispersion liquids in the 150ml beaker, add the 20g acrylamide, 5 gram AMPS, 65ml water, fully stirring and dissolving is 10 minutes, forms prepolymerization liquid, drives oxygen 20 minutes, adds 0.008 gram ammonium persulphate and 0.008 gram sodium bisulfite.Polymerization obtained base polymer in 5 hours under the normal temperature, and base polymer was handled 10 minutes at 99 ℃, handled 1.5 hours for 90 ℃.

The gel water content adopts following formula to calculate:

X＝(Ws-Wd)/Ws

The quality of Ws---swell gel; Wd---corresponding xerogel quality

The test of gel tensile strength is as follows: carry out on the mechanical test machine, it is long that the specimen of employing is of a size of 45mm, and 15mm is wide, and 5mm is thick, and the water content of sample is 90%.

Its result is as follows:

Tensile strength 25Kpa, extensibility 2700%

Embodiment 2:

In the flask of 500ml, add 40 gram acrylamides, 6 gram AMPS, 7 gram N hydroxymethyl acrylamides, 0.04 gram is two the third, 56ml water, add 2.5 gram OP-10,7.5 gram SP80 after fully stirring, adds the 110ml hexanaphthene, add 0.005 gram Potassium Persulphate and 0.01 after 20 minutes with nitrogen flooding oxygen and restrain sodium bisulfite, react the microgel emulsion that obtained to contain the N-methylol in 3 hours as initiator.Again be scattered in the 47 gram water after getting 8.5 gram emulsion dryings.Get 5 gram dispersion liquids in the 150ml beaker, add the 25g acrylamide, 2 gram AMPS, 68ml water, fully stirring and dissolving is 10 minutes, forms prepolymerization liquid, drives oxygen 25 minutes, adds 0.012 gram Potassium Persulphate and 0.012 gram sodium bisulfite.Polymerization obtained base polymer in 4 hours under the normal temperature, and polymkeric substance was handled 10 minutes at 99 ℃, handled 4.5 hours for 90 ℃.

Performance test is with embodiment one, and its result is as follows:

Tensile strength 24Kpa, extensibility 1900%

Embodiment 3:

In the flask of 500ml, add 42 gram acrylamides, 5 gram AMPS, 6 gram N hydroxymethyl acrylamides, 0.03 gram is two the third, 56ml water, add 2.5 gram OP-10,7.5 gram SP20 after fully stirring, adds the 110ml hexanaphthene, add 0.005 gram ammonium persulphate and 0.02 after 20 minutes with nitrogen flooding oxygen and restrain sodium bisulfite, react the microgel emulsion that obtained to contain the N-methylol in 3 hours as initiator.Again be scattered in the 47 gram water after getting the newborn drying of 8.5 grams.Get 14 gram dispersion liquids in the 150ml beaker, add the 20g acrylamide, 4 gram AMPS, 62ml water, fully stirring and dissolving is 10 minutes, forms prepolymerization liquid, drives oxygen 20 minutes, adds 0.005 gram ammonium persulphate and 0.005 gram sodium bisulfite.Polymerization obtained base polymer in 5 hours under the normal temperature, and polymkeric substance was handled 4 hours at 89 ℃.

Performance test is with embodiment one, and its result is as follows:

Tensile strength 37Kpa, extensibility 1900%

Embodiment 4:

Other obtained base polymer with embodiment 3 in 5 hours with polymerization under the normal temperature, handled 3 hours at 80 ℃.

The performance test results is as follows:

Tensile strength 17Kpa, extensibility 1385%

Claims

1. the preparation method of a microgel composite hydrogel is characterized in that may further comprise the steps:

(1) preparation contains the microgel emulsion of N-methylol

Hexanaphthene 40-45%,

Acrylamide 16-23%,

2-acrylamido-2-methyl propane sulfonic acid or vinylformic acid 1-7%,

N hydroxymethyl acrylamide 2-7%,

N, N '-methylene-bisacrylamide 0.005-0.10%,

OP-10：1-3％，

SP20 or SP80:3-9%,

Water: 35-41%,

Ammonium persulphate or Potassium Persulphate: 0.002-0.02%,

Sodium bisulfite: 0.002-0.02%;

(2) preparation dispersion liquid

To be scattered in the water again after the microgel emulsion drying; The component of dispersion liquid and mass percent are: microgel 3-4%, water 96-97%, microgel are meant water-free dried microgel;

(3) preparation pre-polymerization liquid

Acrylamide, 2-acrylamido-2-methyl propane sulfonic acid or vinylformic acid, dispersion liquid, water are mixed acquisition pre-polymerization liquid, the component of its pre-polymerization liquid and mass percent are: acrylamide 20-25%, 2-acrylamido-2-methyl propane sulfonic acid or vinylformic acid 2-5%, dispersion liquid 5-15%, water 60-70%;

(4) polymerization

Pre-polymerization liquid was driven oxygen more than 30 minutes, add the sodium bisulfite of 0.002-0.04% initiator and 0.002-0.04%, normal temperature causes radical polymerization more than 3 hours down, obtains base polymer;

(5) high-temperature heating treatment

The base polymer that step (4) is obtained was at 70-99 ℃ of heat treated 1.5-5 hour.