Aqueous epoxy resins are impact-resistant modified to use core-shell nano lotion preparation process
Technical field
The invention belongs to aqueous epoxy resins toughener field more particularly to a kind of aqueous epoxy resins are impact-resistant modified uses core
Core/shell nanoparticles lotion preparation process.
Background technology
Epoxy resin is a kind of three-dimensional netted thermosetting polymer, is a kind of very strong material of brittleness, toughening modifying
It is polymer science and the important topic of Material Field basic research and application and development, all receives significant attention all the time.But
Simple rubber or elastomer toughening or rigid particles to epoxy resin roughening, all there is some shortcomings.For simple
Rubber or elastic body toughening polymer although impact flexibility has obtained large increase, usually require to add in 10wt%-20wt%
Rubber or elastomer, intensity and modulus loss that this often leads to material is too many;And it is carried out using inorganic rigid particle
Toughening, although the intensity and modulus of material will not lose, the toughness increase rate of material is little, and is not easy in polymer
In uniformly disperse, the finely dispersed composite material of inorganic particulate can not be obtained, especially to the Inorganic Fillers Filled ring of nano-scale
Epoxy resin system, since particle has higher surface can, it is easy to aggregation occur so as to generate defect in the material.
The prior art prepares SiO using conventional emulsion polymerization mode2/ esters of acrylic acid core-shell particles lotion, but due to
Emulsifying process is not suitable for, emulsifier is excessive, the lipophile modification degree of silica is low, eventually leads to coated with silica
Rate is low, straight polymer micelle is more, even if there are indivedual core-shell nanos, coating thickness size is also very greatly and not
Uniformly.
Invention content
The purpose of the present invention is:In view of the deficiencies of the prior art, a kind of clad ratio height, size uniform, shell thickness are provided
Consistent aqueous epoxy resins are impact-resistant modified to use core-shell nano lotion preparation process.
In order to achieve the above object, the present invention provides a kind of impact-resistant modified core-shell nano breasts of aqueous epoxy resins
Liquid preparing process includes the following steps:
Step A is prepared homodisperse nano silicon dioxide using sol-gal process, it is carried out using silane coupling agent
Surface hydrophobicity is modified, and obtains hydrophobicity nano silicon dioxide;
Step B, using pre-emulsification seed emulsion polymerization, using the hydrophobicity nano silicon dioxide that step A is obtained as core knot
Structure is carried out with glycidyl methacrylate monomer polymerizeing cladding with methacrylate, obtains product.
Beneficial effects of the present invention are as follows:1. the preparation-obtained modified silica particles sphericity of this patent is high, ruler
It is very little uniformly, particle diameter distribution it is small, without particle adhesion phenomenon;2. improved silica weight-loss ratio prepared by this patent is 4.55%, even
The grafting rate of connection agent increases substantially;3. the impact-resistant modified core-shell nano lotion of aqueous epoxy resins prepared by the present invention
The loss to matrix modulus can be significantly reduced as toughener, increases substantially the impact strength of entire toughened system,
Improve toughness of products.
Description of the drawings
Fig. 1 is the scanning electron microscope (SEM) photograph of hydrophobicity nano-silicon dioxide particle that the embodiment of the present invention one is prepared.
Fig. 2 is the transmission electron microscope picture of hydrophobicity nano-silicon dioxide particle that the embodiment of the present invention one is prepared.
Fig. 3 is the grain size and distribution tests of hydrophobicity nano-silicon dioxide particle that the embodiment of the present invention one is prepared
Figure.
Fig. 4 is the fourier infrared test for the hydrophobicity nano-silicon dioxide particle that the embodiment of the present invention one is prepared
Figure.
Fig. 5 is the impact-resistant modified core-shell nano lotion of aqueous epoxy resins that the embodiment of the present invention one is prepared
Transmission electron microscope picture.
Fig. 6 is the impact-resistant modified core-shell nano lotion of aqueous epoxy resins that the embodiment of the present invention one is prepared
Grain size and distribution tests figure.
Fig. 7 is the scanning electron microscope (SEM) photograph of silicon dioxide granule that the embodiment of the present invention two is prepared.
Fig. 8 is the fourier infrared test chart of silicon dioxide granule that the embodiment of the present invention two is prepared.
Fig. 9 is the transmission electron microscope picture of particle lotion that the embodiment of the present invention two is prepared.
Specific embodiment
Aqueous epoxy resins prepared by the present invention are impact-resistant modified to use core-shell nano lotion, including using silica as
Kernel, surface are coated with the core-shell structure nanometer particle of polymer, and the general molecular formula of the polymer is:
Wherein x=200-300, y=50-100.The silica kernel it is a diameter of
290-310nm, outer cover polymer layer thickness are 30-50nm.
The aqueous epoxy resins are impact-resistant modified to compare other toughener by the use of core-shell nano lotion as toughener
Advantage be:
1) after the toughener is mixed with epoxy resin, the interface rubber content meeting that is in contact with epoxy molecule segment
More, less rigid content of material is more for internal rubber content, and such structure toughener can be significantly reduced to base
The loss of body modulus;
2) product is in nano-scale, and monodispersity is good, and what can be disperseed in epoxy resin-base is more uniform, when
After product content reaches critical value, coordination plasticizing between each toughening particle increases substantially the impact strength of entire toughened system;
3) product polymer shell is designed as methacrylate and is copolymerized with glycidyl methacrylate monomer,
The epoxy group of polymeric shell layer molecule chain end is enable to react shape with the hydroxyl of epoxy resin, epoxy group isoreactivity group
Into covalent bond, the interface interaction between product and matrix is improved, is conducive to the transmission of impact energy, can finally improve toughness.
The present invention provides a kind of aqueous epoxy resins it is impact-resistant modified use core-shell nano lotion preparation process, including
Following steps:
Step A is prepared homodisperse nano silicon dioxide using sol-gal process, it is carried out using silane coupling agent
Surface hydrophobicity is modified, and obtains hydrophobicity nano silicon dioxide;
Step B, using pre-emulsification seed emulsion polymerization, using the hydrophobicity nano silicon dioxide that step A is obtained as core knot
Structure is carried out with glycidyl methacrylate monomer polymerizeing cladding with methacrylate, obtains product.
Preferably, in the step A, the addition of each component is measured by volumes below number:
Its preparation process includes,
A1 takes segment polarity organic solvent, deionized water and accelerating agent to add in reactor, with 100-400 revs/min of rotating speed
6-12min is stirred, is then improved rotating speed to 800-1500 revs/min, while measure remaining polar organic solvent and positive silicic acid second
Ester is uniformly mixed, and is then mixed drop and is added in reactor, treats that mixed liquor color becomes milky by transparent in reactor
Rotating speed is reduced to 100-380 revs/min afterwards, keeps this tachyphylaxis 2-8h;
A2 continues to stir and adjusts the temperature to 40-50 DEG C, silane coupling agent is then added in into reactor, is kept stirring
Thermotonus 12-30h, drying, dry to obtain hydrophobicity nano silicon dioxide again at washing.
It is further preferred that polar organic solvent and ethyl orthosilicate mixed liquor drop rate are in the step A1
10ml/s-20ml/s.It is prepared compared to the mode for being slowly added dropwise, mixing slowly using fast drop and quick agitating mode
Obtained silica dioxide granule sphericity height, size uniform, particle diameter distribution be small, without particle adhesion phenomenon.
It is further preferred that the silane coupling agent is γ-methacryloxypropyl trimethoxy silane.
It is further preferred that the process dried in the step A2, wash, dried again includes, dispersion liquid is placed in 40-60
DEG C air dry oven is dried to pulverulence, is subsequently placed in 60-100 DEG C of vacuum drying chamber drying 20-30h, then has with polarity
Solvent centrifuge washing 3-4 times, finally drying obtain modified hydrophobic nano silicon dioxide.By increasing by one before centrifuge washing
Walk stage drying the step of, compared to direct centrifuge washing then dry mode so that silica surface it is silane coupled
Agent grafting rate increases substantially.
By step A more than preferred embodiments, prepare a diameter of 290-310nm and silica of uniform size is received
Rice grain, and hydrophobicity modification is carried out to it, make to be grafted upper γ-methacryloxypropyl trimethoxy silicon on its surface
Alkane.
Preferably, in the step B, the addition of each component is measured by following mass fraction:
Its preparation process includes,
B1 adds in water, emulsifier and assistant for emulsifying agent, high-speed stirred 15-50min in reaction kettle and obtains the water-soluble of emulsifier
Liquid;
B2, ultrasound 20-80min in the aqueous solution for the emulsifier that hydrophobicity nano silicon dioxide is added to step B1, then
0.5-2h is stirred with 100-350 revs/min of rotating speed again, obtains hydrophobicity silica pre-emulsion;
The mixed liquor of methacrylate monomers and initiator is added drop-wise in the pre-emulsion that B2 steps obtain and stirred by B3
0.5-2h obtains the monomer droplet of coated silica kernel;Nitrogen 15-35min is subsequently passed, is then heated to 40-90 DEG C,
Reaction time is 3-10h, and glycidyl methacrylate is added dropwise, temperature is increased to 70-96 DEG C, is further continued for reaction 0.5-
2h adjusts pH value to 6-10 to get required product.
It is further preferred that the methacrylate includes methyl methacrylate, ethyl methacrylate, methyl-prop
Olefin(e) acid N-butyl or 2-Propenoic acid, 2-methyl-, octyl ester.
It is further preferred that the emulsifier is lauryl sodium sulfate, sodium hexadecyl sulfate, dodecyl polyoxy second
Alkene ether sodium sulfate, neopelex or dodecyl sodium sulfate.
It is further preferred that the assistant for emulsifying agent is hexadecanol, hexadecane, hexadecylic acid, cetylamine, octadecyl alcolol or 18
Alkane.
It is further preferred that the initiator is hydrogen peroxide, benzoyl peroxide, benzoyl peroxide acetyl or peroxidating two
Isopropylbenzene.
By step B more than preferred embodiments, cladding thickness 30-50nm and evengranular nuclear shell structure nano are prepared
Silica/polymethacrylate emulsion.The compound emulsifying agent composition and the relevant technologies compound emulsifying agent of patent of the present invention are not
Together, the assistant for emulsifying agent kind of such as hexadecane, hexadecanol etc is included;The present invention uses pre-emulsification side in monomer emulsion process
Formula, i.e., first emulsify the hydrophobicity silica being modified in emulsifier aqueous solution, and monomer is then added dropwise again and is emulsified, phase
Pass technology is generally using being silica and monomer emulsifying manner simultaneously, and compared with this, pre-emulsification mode can make monomer more preferable
Absorption monomer corona drop layer is formed around silica;Initiator in patent of the present invention is caused using oil-soluble
Agent, the relevant technologies are generally using water soluble starter;Overall improvement synergistic effect by these techniques so that pre-emulsification
Afterwards package silica each drop monomer size more uniformly, particle diameter distribution smaller, the core-shell particles shell formed after polymerization
Thickness is more in line with product requirement, and also more uniformly, straight polymer particle and exposed silica dioxide granule ratio are big for particle size
Amplitude is reduced.
With reference to specific embodiment, the invention will be further described, but the present invention is not limited to following embodiments.
Embodiment 1
A. measure 45 parts of ethyl alcohol, 25 parts of deionized waters and 10 parts of ammonium hydroxide add in the reactors with magnetic stirring apparatus with
300 revs/min of rotating speeds stir 10 minutes, then improve rotating speed to 1000 revs/min, while measure 15 parts of ethyl alcohol and 4.5 parts of positive silicon
Acetoacetic ester is uniformly mixed, and is then mixed in liquid fast drop to reactor, treats that mixed liquor color is by transparent change in reactor
Rotating speed is reduced to 300 revs/min after into milky, keeps this tachyphylaxis 4h;Continue to stir and adjust the temperature to 40-50 DEG C,
Then 2 parts of silane coupling agents are added in into system, are kept stirring thermotonus for 24 hours, after dispersion liquid is placed in 50 DEG C of forced air dryings
Case is dried to pulverulence, is subsequently placed in 80 DEG C of vacuum drying chamber drying for 24 hours, then with ethyl alcohol centrifuge washing 3-4 times, finally dries
It is dry to obtain modified hydrophobic nano-silicon dioxide particle.
Product test:
1st, Electronic Speculum is tested, in the nano-silicon dioxide particle to 10ml absolute ethyl alcohols for taking the above-mentioned preparations of 0.02g, ultrasonic disperse
Then 30min is dripped on silicon chip, carry out scanning electron microscopic observation after ethyl alcohol volatilization, test result is shown in Fig. 1;It simultaneously will be above-mentioned super
On sound dispersant liquid drop to the copper mesh with carbon film, transmission electron microscope observing is carried out after naturally dry, test result is shown in Fig. 2.It can by Fig. 1
Know, prepared silica dioxide granule is whole, and all very uniformly sphericity is high, no adhesion and agglomeration;As shown in Figure 2, dioxy
Silicon carbide particle size is 290-310nm, and size uniform.
2nd, grain size is tested, and above-mentioned ultrasonic disperse liquid is taken to carry out grain size and be distributed to survey with Malvern grain size tester after diluting
Examination, test result are shown in Fig. 3.From the figure 3, it may be seen that silica dioxide granule is close to monodisperse status.
3rd, fourier infrared is tested, and the modified manometer silicon dioxide of above-mentioned preparation is dried in 80 DEG C of vacuum drying chambers
10h takes out and carries out fourier infrared test, and the grafting situation of silica surface coupling agent is analyzed with this, and test result is shown in figure
4.As shown in Figure 4, using γ-methacryloxypropyl three in the improved silica infared spectrum of this patent technique preparation
The carbonyl peak (1720~cm-1) of methoxy silane characteristic absorption peak has apparent display, illustrates that grafting density significantly rises;
Simultaneously using TG test (30~800 DEG C, 10 DEG C/min, N2Protection) it also shows, the improved silica prepared using this patent
Weight-loss ratio is 4.55% (product weight-loss ratio prepared by other methods is 1%), improves 3.5%, illustrates the grafting rate of coupling agent
It increases substantially.
B. 400 parts of water, 1 part of lauryl sodium sulfate and 0.08 part of hexadecane, high-speed stirred are added in reaction kettle
30min, while 3 parts of above-mentioned steps A modified hydrophobic nano silicon dioxides prepared are added in the aqueous solution of aforementioned emulsifier
Ultrasound 1 hour is then transferred in reaction kettle with 300 revs/min of stirring 1h, is then added dropwise to 2 parts of butyl methacrylates
With 0.04 portion of benzoyl peroxide mixed liquor, continue to be passed through nitrogen 30min after stirring 1h, then begin to warm up to 80 DEG C, react
Time is 5h, and 0.5 part of glycidyl methacrylate of function monomer is added dropwise, temperature is increased to 90 DEG C, is further continued for reaction 1h,
PH value is adjusted to 7-8 up to required product.
Product test:
1st, transmissioning electric mirror test takes lotion prepared by a small amount of step B to be diluted rear ultrasonic disperse with deionized water
Then 30min is dropped on the copper mesh with carbon film, transmission electron microscope observing is carried out after naturally dry, and test result is shown in Fig. 5.It can by Fig. 5
Know, entire polymer covering layer is uniformly distributed around silica sphere, size 30-50nm, and interfacial contact is close.
2nd, grain size is tested, and lotion prepared by a small amount of step B is taken to be diluted rear ultrasonic disperse 30min with deionized water, is taken
Grain size and distribution tests are carried out with Malvern grain size tester after above-mentioned ultrasonic disperse liquid dilution, test result is shown in Fig. 6.By Fig. 6
It is found that core-shell particles dispersion degree is small, show that particle size is highly uniform.
Embodiment 2
A. measure 45 parts of ethyl alcohol, 25 parts of deionized waters and 10 parts of ammonium hydroxide add in the reactors with magnetic stirring apparatus with
300 revs/min of rotating speeds stir 10 minutes, while 15 parts of ethyl alcohol of measurement and 4.5 parts of ethyl orthosilicates are uniformly mixed, and are then mixed
Liquid is added dropwise to 2ml/min speed in reactor with dropping funel, reacts 4h after being added dropwise;Continue to stir and adjust the temperature to
40-50 DEG C, 2 parts of silane coupling agents are then added in into system, thermotonus are kept stirring for 24 hours, with ethyl alcohol centrifuge washing 3-4
Secondary, finally drying obtains modified hydrophobic nano-silicon dioxide particle.
Product test:
1st, Electronic Speculum is tested, in the nano-silicon dioxide particle to 10ml absolute ethyl alcohols for taking the above-mentioned preparations of 0.02g, ultrasonic disperse
Then 30min is dripped on silicon chip, carry out scanning electron microscopic observation after ethyl alcohol volatilization, test result is shown in Fig. 7;As shown in Figure 7,
Particle size is uneven, and adhesion particle is more, reunites serious.
2nd, fourier infrared is tested, and the modified manometer silicon dioxide of above-mentioned preparation is dried in 80 DEG C of vacuum drying chambers
10h takes out and carries out fourier infrared test, and the grafting situation of silica surface coupling agent is analyzed with this, and test result is shown in figure
8, as shown in Figure 8, the characteristic absorption of γ-methacryloxypropyl trimethoxy silane in improved silica infared spectrum
Peak carbonyl peak (1720~cm-1) is not shown, is illustrated modified unsuccessful.
B. reaction kettle add in 400 parts water and 1 part of lauryl sodium sulfate, high-speed stirred 30min, while will be on 3 parts
Nano silicon dioxide, 2 parts of butyl methacrylates, 0.08 part of hexadecane, 0.04 benzoyl peroxide for stating step A preparations mix
Drop is added in the aqueous solution of aforementioned emulsifier and stirs 1 hour, is passed through nitrogen 30min, then begins to warm up to 80 DEG C, during reaction
Between for 5h, 0.5 part of glycidyl methacrylate of function monomer is added dropwise, temperature is increased to 90 DEG C, is further continued for reaction 1h, adjusts
PH value is saved to 7-8 up to required product.
Product test:
1st, transmissioning electric mirror test takes lotion prepared by a small amount of step B to be diluted rear ultrasonic disperse with deionized water
Then 30min is dropped on the copper mesh with carbon film, transmission electron microscope observing is carried out after naturally dry, and test result is shown in Fig. 9.It can by Fig. 9
Know, monomer droplet dispersion is uneven to cause the sub- adhesion of core-shell latex particles serious.
Embodiment 3
A. measure 45 parts of ethyl alcohol, 30 parts of deionized waters and 10 parts of ammonium hydroxide add in the reactors with magnetic stirring apparatus with
300 revs/min of rotating speeds stir 10 minutes, then improve rotating speed to 1000 revs/min, while measure 15 parts of ethyl alcohol and 3 parts of positive silicic acid
Ethyl ester is uniformly mixed, and is then mixed in liquid fast drop to reactor, treats that mixed liquor color is become by transparent in reactor
Rotating speed is reduced to 300 revs/min after milky, keeps this tachyphylaxis 4h;Continue to stir and adjust the temperature to 40-50 DEG C, so
2 parts of silane coupling agents are added in backward system, are kept stirring thermotonus for 24 hours, after dispersion liquid is placed in 50 DEG C of air dry ovens
Pulverulence is dried to, is subsequently placed in 80 DEG C of vacuum drying chamber drying for 24 hours, then with ethyl alcohol centrifuge washing 3-4 times, is finally dried
Obtain modified hydrophobic nano-silicon dioxide particle;
B. 400 parts of water, 1 part of lauryl sodium sulfate and 0.08 part of hexadecanol, high-speed stirred are added in reaction kettle
30min, while 3 parts of above-mentioned steps A modified hydrophobic nano silicon dioxides prepared are added in the aqueous solution of aforementioned emulsifier
Ultrasound 1 hour is then transferred in reaction kettle with 300 revs/min of stirring 1h, is then added dropwise to 10 parts of butyl methacrylates
With 0.2 portion of benzoyl peroxide mixed liquor, continue to be passed through nitrogen 30min after stirring 1h, then begin to warm up to 80 DEG C, during reaction
Between for 5h, 0.5 part of glycidyl methacrylate of function monomer is added dropwise, temperature is increased to 90 DEG C, is further continued for reaction 1h, adjusts
PH value is saved to 7-8 up to required product.
Embodiment 4
A. measure 45 parts of ethyl alcohol, 30 parts of deionized waters and 10 parts of ammonium hydroxide add in the reactors with magnetic stirring apparatus with
300 revs/min of rotating speeds stir 10 minutes, then improve rotating speed to 1000 revs/min, while measure 15 parts of ethyl alcohol and 3 parts of positive silicic acid
Ethyl ester is uniformly mixed, and is then mixed in liquid fast drop to reactor, treats that mixed liquor color is become by transparent in reactor
Rotating speed is reduced to 300 revs/min after milky, keeps this tachyphylaxis 4h;Continue to stir and adjust the temperature to 40-50 DEG C, so
5 parts of silane coupling agents are added in backward system, are kept stirring thermotonus for 24 hours, after dispersion liquid is placed in 50 DEG C of air dry ovens
Pulverulence is dried to, is subsequently placed in 80 DEG C of vacuum drying chamber drying for 24 hours, then with ethyl alcohol centrifuge washing 3-4 times, is finally dried
Obtain modified hydrophobic nano-silicon dioxide particle;
B. 400 parts of water, 5 parts of lauryl sodium sulfate and 0.08 part of hexadecane, high-speed stirred are added in reaction kettle
30min, while 3 parts of above-mentioned steps A modified hydrophobic nano silicon dioxides prepared are added in the aqueous solution of aforementioned emulsifier
Ultrasound 1 hour is then transferred in reaction kettle with 300 revs/min of stirring 1h, is then added dropwise to 8 parts of butyl methacrylates
With 0.16 portion of benzoyl peroxide mixed liquor, continue to be passed through nitrogen 30min after stirring 0.2h, then begin to warm up to 80 DEG C, instead
It is 5h between seasonable, 0.5 part of glycidyl methacrylate of function monomer is added dropwise, temperature is increased to 90 DEG C, is further continued for reacting
1h adjusts pH value to 7-8 up to required product.
Embodiment 5
A. measure 45 parts of ethyl alcohol, 25 parts of deionized waters and 10 parts of ammonium hydroxide add in the reactors with magnetic stirring apparatus with
300 revs/min of rotating speeds stir 10 minutes, then improve rotating speed to 1000 revs/min, while measure 15 parts of ethyl alcohol and 4.5 parts of positive silicon
Acetoacetic ester is uniformly mixed, and is then mixed in liquid fast drop to reactor, treats that mixed liquor color is by transparent change in reactor
Rotating speed is reduced to 300 revs/min after into milky, keeps this tachyphylaxis 4h;Continue to stir and adjust the temperature to 40-50 DEG C,
Then 2 parts of silane coupling agents are added in into system, are kept stirring thermotonus for 24 hours, after dispersion liquid is placed in 50 DEG C of forced air dryings
Case is dried to pulverulence, is subsequently placed in 80 DEG C of vacuum drying chamber drying for 24 hours, then with ethyl alcohol centrifuge washing 3-4 times, finally dries
It is dry to obtain modified hydrophobic nano-silicon dioxide particle;
B. 300 parts of water, 1 part of lauryl sodium sulfate and 0.08 part of hexadecane, high-speed stirred are added in reaction kettle
30min, while 3 parts of above-mentioned steps A modified hydrophobic nano silicon dioxides prepared are added in the aqueous solution of aforementioned emulsifier
Ultrasound 1 hour is then transferred in reaction kettle with 300 revs/min of stirring 1h, is then added dropwise to 5 parts of ethyl methacrylate
0.1 part of cumyl peroxide mixed liquor continues to be passed through nitrogen 30min after stirring 1h, then begins to warm up to 80 DEG C, react
Time is 5h, and 0.5 part of glycidyl methacrylate of function monomer is added dropwise, temperature is increased to 90 DEG C, is further continued for reaction 1h,
PH value is adjusted to 7-8 up to required product.