CN101463135A - Preparation of water-dispersion polyamic acid particle - Google Patents
Preparation of water-dispersion polyamic acid particle Download PDFInfo
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- CN101463135A CN101463135A CNA2009100664285A CN200910066428A CN101463135A CN 101463135 A CN101463135 A CN 101463135A CN A2009100664285 A CNA2009100664285 A CN A2009100664285A CN 200910066428 A CN200910066428 A CN 200910066428A CN 101463135 A CN101463135 A CN 101463135A
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Abstract
The invention belongs to the field of high molecular materials, specifically relates to a preparation method of a water dispersible polyamic acid particle. The polyamic acid particle has wide application to environment-friendly polyimide materials. The preparation method comprises the following steps: taking a mol of dianhydride monomers in the presence of nitrogen gas to dissolve or disperse in an organic solvent, and then slowly adding c mol of diamine monomers with the solid content in the solution being 0.1-40wt%; stirring the solution at the room temperature for 2-24h, then adding b mol of anhydride, and continuing to stir at the room temperature for 2-24h to obtain thick liquid that is the polyamic acid solution, wherein, a, b and c satisfy a relation that a plus 2b equals c, or when b equals 0, a/c ratio equals 0.1-5:1; then diluting the obtained polyamic acid solution by the organic solvent until the solution has the solid content of 0.01-10wt%; and preparing in a spray dryer to obtain the water dispersible polyamic acid particles . The method has the excellent effects of simplifying processing technology, lowering processing cost and improving the environmental protection property.
Description
Technical field
The invention belongs to polymeric material field, be specifically related to a kind of preparation method of water-dispersion polyamic acid particle, this polyamic acid particle has application widely aspect the polyimide environment-friendly materials.
Background technology
The special engineering plastics polyimide is because it has excellent thermal characteristics, mechanical property, performance such as corrosion-resistant, obtained using widely in various engineerings field, but this high-performance polymer is insoluble to general organic solvent, thereby the preparation of most of polyimide is further to add catalyzer and dewatering agent or thermal dehydration imidization via the good slightly precursor-polyamic acid of solvability to form.Polyamic acid (PAA) dissolves in N, N '-dimethyl formamide (DMF), N, N '-N,N-DIMETHYLACETAMIDE (DMAc), N-methyl isophthalic acid-pyrrolidone (NMP) wait a few strong polar aprotic solvent, but bigger to the injury that environment and human body cause in processing and the use of a large amount of organic solvents of use.In order to increase polyamic acid at common environmentally friendly solvent, as dispersiveness in ethanol, acetone and the water or solvability, a large amount of research and report all concentrate in the improvement of polymer architecture, comprise sulfonation, add large volume side group and compound with other materials, but such improvement general be cost all with the long-term structural stability or the tooling cost of sacrificial polymer.
Summary of the invention
The objective of the invention is to prepare a kind of water dispersible polyamic acid particle material and preparation method thereof.The present invention is under the prerequisite that does not change polymer architecture, take into account simplified processing process, prepared the polyamic acid powder of water dispersible, preparation technology is simple, and the preparation method has universality, be applicable to most of soluble polyamide acid, the economic environmental protection of preparation method, solvent for use is all recyclable in Industrial processes utilizes again, greatly reduces tooling cost, the polyamic acid powder that makes can be applicable to the polyimide environment-friendly materials, as environmental protection coating material.
The present invention selects a kind of diamines and a kind of dianhydride copolymerization, the molecular weight of the ratio control polymkeric substance by allocating dianhydride and diamines, the molecular weight of the further controlling polymers of use by single acid anhydride again; Water-dispersion polyamic acid particle preparation involved in the present invention comprises following two steps: preparation two portions of the synthetic and polyamic acid powder of polyamic acid.
Polyimide is to be raw material with diamines and acid anhydride, with strong polar aprotic solvent such as N, N '-dimethyl formamide (DMF), N, N '-N,N-DIMETHYLACETAMIDE (DMAc), N-methyl isophthalic acid-pyrrolidone non-inflammable and explosive solvents such as (NMP) are as solvent, and its structural formula and reaction formula are as follows:
N represents the polymerization degree, is positive integer,
A, b, c are mole number, and the following condition that satisfies condition is arbitrary:
1)a+2b＝c；
2)b＝0，a：c＝0.1～5：1
Wherein Ar1 is:
Ar2 is:
Ar3 is:
Instrument used in the present invention is the spray-dryer that is widely used in dry field, and particular type comprises air-flowing type, pressure type, centrifugal, low pressure mixed-flow.
Do not add any tensio-active agent in the production process of the present invention, under simple processing condition, obtained ideal results.
The polyamic acid morphology microstructure that obtains among the present invention changes from micro-nano bead, distortion particle to annular particles (30nm～20 μ m), has good water dispersible, and maximum dispersion concentration can reach 25%, minimumly reaches 9.6%.
The productive rate that the present invention obtains the water dispersible polyamic acid particle is 20%～80%, adds many group retrieving arrangements and be expected to make the productive rate of product higher in actual industrial production.
The preparation method of a kind of water-dispersion polyamic acid particle of the present invention, its step is as follows:
A: under the nitrogen protection, getting the amol dianhydride monomer is dissolved in or is scattered in the organic solvent, then slowly add the cmol diamine monomer, under room temperature, stirred 2～24 hours, add the single acid anhydride of bmol again, the solid content of polymkeric substance is 0.1～40wt% in the solution, continues to stir under the room temperature 2～24 hours, obtain thick liquid, i.e. polyamic acid solution; A:c=0.1～5:1 during wherein a+2b=c, or b=0;
B: with organic solvent diluting gained polyamic acid solution to solid content is 0.01～10wt%, in spray-dryer, prepare the water-dispersion polyamic acid powder granule, the air compressor wind speed of spray-dryer is 10～25 liters/minute, the atomizer inlet temperature is 120～220 ℃, and sample introduction speed is 1.0～60 rev/mins.
Diamine monomer described in the aforesaid method is 3; 3 '-diaminodiphenyl oxide; 3; 4 '-diaminodiphenyl oxide; 4; 4 '-diaminodiphenyl oxide (4,4 '-ODA); 1,3;-(3-amino-benzene oxygen) benzene; 1; 4 ,-(4-amino-benzene oxygen) benzene; 1,4;-(3-amino-benzene oxygen) benzene; 1; 3 ,-(4-amino-benzene oxygen) benzene; benzene is for 1,4;-(4-amino-benzene oxygen) benzene; 4; 4 '-two (3-amino-benzene oxygen) benzophenone (APBP); 1,3-phenylene two (4-(4-amine phenoxy group) benzene) benzophenone or 1,3-two (3-amino-benzene oxygen-4-benzoyl group) benzene (BABB).
Dianhydride monomer described in the aforesaid method is 3,3 ', 4,4 '-BPDA (s-BPDA), pyromellitic acid dianhydride (PMDA), phenyl ether tetracarboxylic dianhydride (ODPA), benzophenone tetracarboxylic dianhydride (BTDA), 2,3 ', 3,4 '-BPDA or 2,3 ', 2,3 '-BPDA.
Single acid anhydride described in the aforesaid method is 4-acetylene anhydride, 4-phenylacetylene phthalic anhydride (PEPA) or phthalic anhydride.
Organic solvent described in the aforesaid method is N-Methyl pyrrolidone (NMP), N, dinethylformamide (DMF) or N,N-dimethylacetamide (DMAc), or two or three mixed solvent of above-mentioned solvent.
The present invention has obtained the polyamic acid particle of water-dispersion by spray-dired method, compares with tradition processing, and the preparation method is simple, and a large amount of solvent phase that remaining a small amount of solvent and tradition processing expend in the particle are than environmental protection more, low consumption.
Description of drawings
Fig. 1: spray-dryer synoptic diagram;
The water dispersible polyamic acid powder scanning electron microscope picture that Fig. 2: embodiment 1 obtains;
The water dispersible polyamic acid powder scanning electron microscope picture that Fig. 3: embodiment 2 obtains;
The water dispersible polyamic acid powder scanning electron microscope picture that Fig. 4: embodiment 4 obtains;
The water dispersible polyamic acid powder stereoscan photograph that Fig. 5: embodiment 9 obtains.
As shown in Figure 1, the preferred spray-dryer of the present invention is the GPW120-II type mini spray moisture eliminator that Tianli Drying Equipment Co., Ltd., Shandong produces.Wherein, 1 is the feed liquid injection port, 2 peristaltic pumps for control feed liquid sample introduction speed, 3 is the air compressor of control air speed, and 4 is dry gas (warm air), and 5 is the spray-dryer import, the spray-dryer outlet of 6 places, 7 is sample divider, and 8 is cyclonic separation (cyclone dust removal) device, and 9 is exhaust outlet.
The operating process of spray-dryer: open air compressor 3, regulate wind speed and be stabilized in V1 (V1=10～25 liter/minute), opening dry gas enters the mouth to maximum, and then regulate the atomizer inlet temperature to T1 (T1=120～150 ℃), organic solvent is placed the injection port of spray-dryer, suck at inlet under the situation of organic solvent, regulate peristaltic pump control sample introduction speed V2 (V2=1.0～60 rev/min), continue to regulate inlet temperature to T2 (T2=120～220 ℃), after inlet temperature and temperature out are stable, change organic solvent into polyamic acid solution that the front has prepared, control inlet temperature T2, wind speed V1, V2 is constant for sample introduction speed.After preparation process finishes, in the collector or cyclonic separator bottom visible powdered samples, i.e. water-dispersion polyamic acid powder granule.
Fig. 2 is the representative picture of distortion particle and annular particles, and granular size is 1 μ m～20 μ m, major part ringwise, small part is a bowl type.
Fig. 3 is the typical representative picture of spheroidal particle, and granular size is 200nm～4 μ m, and particle presents intact sphere.
Fig. 4 is a distortion particulate representative picture, and granular size is 100nm～7 μ m, and depression is arranged on the particle.
Fig. 5 is a distortion particulate representative picture, and granular size is 300nm～3 μ m, and major part is bowl type or the particle that caves in more.
By the water-dispersion performance test (testing method: sample is placed in the sample hose that sample is carried out, the weighing sample quality, progressively drip distilled water or ethanol weighing solution quality, ultra-sonic dispersion, to disperseing first fully, the massfraction of calculation sample is a maximum dispersion concentration), prove that the polyamic acid particle that we obtain has good water dispersible, have good application may with prospect.
Embodiment
Embodiment 1:
Under induction stirring, under the nitrogen atmosphere, in three-necked bottle, add 4,4 '-diaminodiphenyl oxide (4,4 '-ODA) 1.0012g (0.005mol) is dissolved in 18.8262g N, and N '-N,N-DIMETHYLACETAMIDE (DMAc) slowly adds pyromellitic acid dianhydride (PMDA) 1.0906g (0.005mol) again, induction stirring is 4 hours under the room temperature, obtains transparent thick liquid-polyamic acid solution (solid content is 10wt%).
With N, viscous solution to the solid content that N '-N,N-DIMETHYLACETAMIDE (DMAc) dilution obtains previously is 1wt%, spraying drying, inlet temperature T2=170 ℃, wind speed V1=25 liter/minute, V2=12.0 rev/min of sample introduction speed, experiment finish in the collector of back or cyclonic separation (being cyclone dust removal) bottom visible powdered samples, i.e. water-dispersion polyamic acid powder granule.Characterize the discovery resulting granules by scanning electron microscope and be distortion particle and annular, recording sample maximum dispersion concentration through water dispersible is 22.9%.
Embodiment 2:
Method such as embodiment 1; dianhydride becomes 2.6480g (0.009mol) 3,3 ', 4; 4 '-BPDA (s-BPDA); slowly add diamines 5.0054g (0.01mol) 1 again, 3-two (3-amino-benzene oxygen-4-benzoyl group) benzene (BABB) stirs after 4 hours; slowly add 0.4965g (0.002mol) 4-phenylacetylene phthalic anhydride (PEPA) again; continue to stir 4 hours, N, N '-N,N-DIMETHYLACETAMIDE (DMAc) quality becomes 73.3491g.Scanning electron microscope shows that sample is spherical, and it is 9.6% that water dispersible records maximum dispersion concentration.
Embodiment 3:
Method such as embodiment 1; diamines is become 5.0054g (0.01mol) 1; 3-two (3-amino-benzene oxygen-4-benzoyl group) benzene (BABB); dianhydride becomes 2.9422g (0.01mol) 3; 3 ', 4,4 '-BPDA (s-BPDA); N, N '-N,N-DIMETHYLACETAMIDE (DMAc) quality becomes 71.5284g.Scanning electron microscope shows that sample is spherical, and it is 24.7% that water dispersible records maximum dispersion concentration.
Embodiment 4:
Method such as embodiment 1, diamines is become 3.9644g (0.01mol) 4,4 '-two (3-amino-benzene oxygen) benzophenone (APBP), dianhydride becomes 2.9422g (0.01mol) 3,3 ', 4,4 '-BPDA (s-BPDA), N, N '-N,N-DIMETHYLACETAMIDE (DMAc) quality becomes 62.1594g.Scanning electron microscope shows that sample is the distortion particle, and it is 17.6% that water dispersible records maximum dispersion concentration.
Embodiment 5:
Method such as embodiment 1 become 1.9822g (0.005mol) 4,4 '-two (3-amino-benzene oxygen) benzophenone (APBP) with diamines, N, and N '-N,N-DIMETHYLACETAMIDE (DMAc) quality becomes 27.6552g.Scanning electron microscope shows that sample is spherical, and it is 22.3% that water dispersible records maximum dispersion concentration.
Embodiment 6:
Method such as embodiment 1 become 2.5027g (0.005mol) 1 with diamines, 3-two (3-amino-benzene oxygen-4-benzoyl group) benzene (BABB), and N, N '-N,N-DIMETHYLACETAMIDE (DMAc) quality becomes 32.3397g.Scanning electron microscope shows that sample is spherical, and it is 15.0% that water dispersible records maximum dispersion concentration.
Embodiment 7:
Method such as embodiment 1 become 1.4711g (0.005mol) 3,3 ', 4 with dianhydride, 4 '-BPDA (s-BPDA), and N, N '-N,N-DIMETHYLACETAMIDE (DMAc) quality becomes 82.41g, and solid content is 3%, redilution not, inlet temperature is 180 ℃.Sample is the distortion particle, and it is 23.6% that water dispersible records maximum dispersion concentration.
Embodiment 8:
Method such as embodiment 1, diamines is become 3.9644g (0.01mol) 4,4 '-two (3-amino-benzene oxygen) benzophenone (APBP), and dianhydride becomes 3.2223g (0.01mol) benzophenone tetracarboxylic dianhydride (BTDA), N, N '-N,N-DIMETHYLACETAMIDE (DMAc) quality becomes 64.6803g.Sample is the distortion particle, and it is 19.8% that water dispersible records maximum dispersion concentration.
Embodiment 9:
Method such as embodiment 1 become 5.0017g (0.017mol) with the diamines quality, and dianhydride becomes 3.2038g (0.016mol) 3,3 ', 4,4 '-BPDA (s-BPDA), N, N '-N,N-DIMETHYLACETAMIDE (DMAc) quality becomes 73.8502g, and weaker concn is 4.48 ‰.Sample is the distortion particle, and it is 23.70% that water dispersible records maximum dispersion concentration.
Claims (7)
1, a kind of preparation method of water-dispersion polyamic acid particle, its step is as follows:
A: under the nitrogen protection, getting a mol dianhydride monomer is dissolved in or is scattered in the organic solvent, then slowly add c mol diamine monomer, solid content is 0.1～40wt% in the solution, stirs under room temperature 2～24 hours, add the single acid anhydride of b mol again, continue at and stirred under the room temperature 2～24 hours, obtain thick liquid, i.e. polyamic acid solution, a:c=0.1～5:1 during wherein a+2b=c, or b=0;
B: with organic solvent diluting gained polyamic acid solution to solid content is 0.01～10wt%, prepares the water-dispersion polyamic acid powder granule in spray-dryer.
2; the preparation method of a kind of water-dispersion polyamic acid particle as claimed in claim 1; it is characterized in that: diamine monomer is 3; 3 '-diaminodiphenyl oxide; 3; 4 '-diaminodiphenyl oxide; 4,4 '-diaminodiphenyl oxide; 1,3;-(3-amino-benzene oxygen) benzene; 1; 4 ,-(4-amino-benzene oxygen) benzene; 1,4;-(3-amino-benzene oxygen) benzene; 1; 3 ,-(4-amino-benzene oxygen) benzene; benzene is for 1,4;-(4-amino-benzene oxygen) benzene; 4; 4 '-two (3-amino-benzene oxygen) benzophenone; 1,3-phenylene two (4-(4-amine phenoxy group) benzene) benzophenone or 1,3-two (3-amino-benzene oxygen 4-benzoyl group) benzene.
3, the preparation method of a kind of water-dispersion polyamic acid particle as claimed in claim 1, it is characterized in that: dianhydride monomer is 3,3 ', 4,4 '-BPDA, pyromellitic acid dianhydride, phenyl ether tetracarboxylic dianhydride, benzophenone tetracarboxylic dianhydride, 2,3 ', 3,4 '-BPDA or 2,3 ', 2,3 '-BPDA.
4, the preparation method of a kind of water-dispersion polyamic acid particle as claimed in claim 1 is characterized in that: single acid anhydride is 4-acetylene anhydride, 4-phenylacetylene phthalic anhydride or phthalic anhydride.
5, the preparation method of a kind of water-dispersion polyamic acid particle as claimed in claim 1, it is characterized in that: organic solvent is N-Methyl pyrrolidone, N, dinethylformamide or N,N-dimethylacetamide, or two or three mixed solvent of above-mentioned solvent.
6, the preparation method of a kind of water-dispersion polyamic acid particle as claimed in claim 1 is characterized in that: spray-dryer is air-flowing type, pressure type, centrifugal or low pressure mixed flow type atomizing moisture eliminator.
7, as the preparation method of claim 1 or 6 described a kind of water-dispersion polyamic acid particles, it is characterized in that: the air compressor wind speed of spray-dryer is 10～25 liters/minute, the atomizer inlet temperature is 120～220 ℃, and sample introduction speed is 1.0～60 rev/mins.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010036170A1 (en) * | 2008-09-23 | 2010-04-01 | Nexam Chemical Ab | Acetylenic polyamide |
| CN102585253A (en) * | 2011-12-23 | 2012-07-18 | 云南云天化股份有限公司 | Preparation method of thermoplastic polyimide (TPI) particles for modifying surfaces of polyimide (PI) films |
| CN102702744A (en) * | 2012-05-29 | 2012-10-03 | 河北工业大学 | Method for preparing polyimide/carbon nanotube nanocomposite |
| CN104098772A (en) * | 2014-07-29 | 2014-10-15 | 上海华谊（集团）公司 | Novel polyamide-imide preparation method |
| CN110272543A (en) * | 2019-06-20 | 2019-09-24 | 青岛科思姆新材料有限公司 | A kind of polyimide foam hollow microsphere preparation method |
| CN112552513A (en) * | 2020-12-08 | 2021-03-26 | 珠海长先新材料科技股份有限公司 | Synthesis process of nano polyimide micro powder |
| CN112876680A (en) * | 2021-02-04 | 2021-06-01 | 武汉柔显科技股份有限公司 | Polyamide acid slurry, preparation method thereof and polyimide film |
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2009
- 2009-01-13 CN CNA2009100664285A patent/CN101463135A/en active Pending
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010036170A1 (en) * | 2008-09-23 | 2010-04-01 | Nexam Chemical Ab | Acetylenic polyamide |
| US8492507B2 (en) | 2008-09-23 | 2013-07-23 | Nexam Chemical Ab | Acetylenic polyamide |
| CN102585253A (en) * | 2011-12-23 | 2012-07-18 | 云南云天化股份有限公司 | Preparation method of thermoplastic polyimide (TPI) particles for modifying surfaces of polyimide (PI) films |
| CN102585253B (en) * | 2011-12-23 | 2014-07-09 | 云南云天化股份有限公司 | Preparation method of thermoplastic polyimide (TPI) particles for modifying surfaces of polyimide (PI) films |
| CN102702744A (en) * | 2012-05-29 | 2012-10-03 | 河北工业大学 | Method for preparing polyimide/carbon nanotube nanocomposite |
| CN102702744B (en) * | 2012-05-29 | 2013-09-04 | 河北工业大学 | Method for preparing polyimide/carbon nanotube nanocomposite |
| CN104098772A (en) * | 2014-07-29 | 2014-10-15 | 上海华谊（集团）公司 | Novel polyamide-imide preparation method |
| CN104098772B (en) * | 2014-07-29 | 2016-08-24 | 上海华谊（集团）公司 | A kind of preparation method of polyamidoimide |
| CN110272543A (en) * | 2019-06-20 | 2019-09-24 | 青岛科思姆新材料有限公司 | A kind of polyimide foam hollow microsphere preparation method |
| CN110272543B (en) * | 2019-06-20 | 2021-08-31 | 青岛科思姆新材料有限公司 | Preparation method of polyimide foam hollow microspheres |
| CN112552513A (en) * | 2020-12-08 | 2021-03-26 | 珠海长先新材料科技股份有限公司 | Synthesis process of nano polyimide micro powder |
| CN112876680A (en) * | 2021-02-04 | 2021-06-01 | 武汉柔显科技股份有限公司 | Polyamide acid slurry, preparation method thereof and polyimide film |
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