CN1317344C - Hydrophilic antifrosting coating - Google Patents
Hydrophilic antifrosting coating Download PDFInfo
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- CN1317344C CN1317344C CNB2004101012549A CN200410101254A CN1317344C CN 1317344 C CN1317344 C CN 1317344C CN B2004101012549 A CNB2004101012549 A CN B2004101012549A CN 200410101254 A CN200410101254 A CN 200410101254A CN 1317344 C CN1317344 C CN 1317344C
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- frosting
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25D—REFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
- F25D21/00—Defrosting; Preventing frosting; Removing condensed or defrost water
- F25D21/04—Preventing the formation of frost or condensate
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- Combustion & Propulsion (AREA)
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- General Engineering & Computer Science (AREA)
- Application Of Or Painting With Fluid Materials (AREA)
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Abstract
The present invention relates to a hydrophilic anti-frosting paint which can be applied to household refrigerators, large-sized refrigerating rooms and other refrigeration plants, and belongs to the field of refrigeration at low temperature. The hydrophilic anti-frosting paint is characterized in that the paint comprises 20 to 60 portions (weight) of high water absorption resin any or any combined copolymers using acrylate, acrylic amide and methacrylic acid ester as hydrophilic monomers, 30 to 60 portions (weight) of paint using one kind of alcohol acid, epoxy, acrylic acid and phenolic resin as base materials and 30 to 50 portions (weight) of glycerol. The anti-frosting paint is mainly characterized in that the high water absorption resin is combined with the glycerol. The adoption of the anti-frosting paint can delay the time of initial frost crystals at least more than 3 hours under the conditions of low (lower than 50%) air humidity and relatively high (at least 10 DEG C) temperature of wall surfaces and can also reduce the quantity of frost formation by about 50%. The paint can also maintain the state of no frost formation under certain conditions, and has favorable performance of repeated use.
Description
Technical field
The present invention relates to a kind of hydrophilic antifrosting coating, can be applicable to belong to low temperature, refrigerating field in home freezer, large cold storage and other refrigeration equipments.
Background technology
The frosting phenomenon is ubiquity in nature and low temperature field, and frosting has many harm, and especially in refrigeration equipment, frost layer exchange hot side is a thermofin, greatly reduces heat transfer efficiency.In refrigerator and large cold storage, because the frost layer has covered wall, along with thickening of frost layer, white surface temperature can raise gradually, thereby equipment does not reach the temperature of setting and make article rotten.Currently used Defrost method all is based on the thinking of " defrosting ", promptly when tying certain thickness, the frost layer will defrost, electrical heating method, method such as closure systems are clocklike arranged, but these methods all are the energy with consume valuable is cost, so people have carried out the research of various antifrosting coatings, attempt to prevent frosting, to reach the purpose of save energy by being coated with one deck antifrosting coating at cold wall surface.
At present, there are following two kinds by adopting the mechanism that suppresses frosting at cold wall surface coating: one, make cold wall surface present hydrophobicity, the wall contact angle is increased; Two, make cold wall surface present wetting ability.First method can make the globule that forms at the frosting initial stage increase with the wall contact angle, and contact area reduces, and slow thereby the globule freezes, initial hoar crystal forms late, but along with the reduction of wall temperature, and frost is in case formation, and hydrophobic surface is just ineffective.Second method mainly is the suction character by the employing water-absorbing polymer, and the globule of drawing the formation of frosting initial stage comes frost prevention, but often can not reuse, and the effective constituent of coating is volatile.Some hydrophilic antifrosting coatings that occur can only satisfy the frosting phenomenon that prevents occurring in nature at present, and are then ineffective to the frosting under the low temperature.The antifrosting coating of developing at the frosting in the cyrogenic equipment also exists many shortcomings, for example, someone adopts and adds ethylene glycol suppress frosting in superpolymer, though this coating has obtained certain antifrost effect, but be easy to volatilization, just ineffective through three experiments, the somebody directly is coated onto cold wall surface with dense glycerol solution, water vapour constantly is condensed in the dense glycerol solution, reached the effect of frost-free in the short period of time, but the adhesive ability of glycerol solution and wall is poor, will soon be taken away by primary air or white melting layer after washed away.Just the best antifrosting coating of reporting at present of effect can make frosting degree reduce in 30%, so prevent that the coating of frosting from mainly containing following shortcoming under the existing low temperature: antifrost effect is poor, and the frost prevention composition in the organic coating is volatile, and life cycle is short.
Summary of the invention
The object of the present invention is to provide a kind of antifrost effect that is applied in the refrigeration equipment obvious, the not volatile and good antifrosting coating of use properties repeatedly.
The antifrosting coating that the present invention developed presents wetting ability, it is characterized in that comprising 20～60 parts by mass ratio is the High hydrophilous resin of any multipolymer of hydrophilic monomer with acrylate, acrylamide and methacrylic ester, or with arbitrary High hydrophilous resin that is combined as the multipolymer of hydrophilic monomer of acrylate, acrylamide and methacrylic ester, 30～60 parts is the varnish of base-material with in Synolac, Resins, epoxy, acrylic resin, the resol any, 30～50 parts glycerol.The principal character of this antifrosting coating is High hydrophilous resin is combined with glycerol, and the amount of High hydrophilous resin and glycerol is many more, and antifrost effect is good more, but the corresponding increase of the swelling property of coating meeting, sticking power can corresponding decline.Can also add corresponding solvent and auxiliary agent in mixed solution in making processes, solvent plays the effect of dilution, be convenient to apply, but solution is rare more, and antifrost effect can be poor more, and the effect of auxiliary agent is a rate of drying of accelerating coating.
During coating, can adopt conventional coating method, for example spray, brushing, flow coating etc.
Hydrophilic antifrosting coating of the present invention why have anti-frosting function be because: contain polarity group in the molecule of the super absorbent resin that wherein contains, and has certain degree of crosslinking, it is a kind of three-dimensional space network structure, this special chemical structure and reticulated structure make it can absorb a large amount of water.Glycerol can with High hydrophilous resin and the Synolac that is adopted, Resins, epoxy, acrylic resin, resol class coating dissolves each other, not volatile, and glycerol can moisture absorption, the more important thing is that glycerol is effective frostproofer, freezing point is below 0 ℃, and how many meetings of water content obviously influence its freezing point, moisture 50% o'clock, freezing point is-23 ℃, moisture 66.7% o'clock, freezing point is at-46.5 ℃, do not freeze so the moisture that adopts this antifrosting coating that the frosting initial stage is absorbed remains in the temperature of certain limit below freezing, thereby coating can postpone the formation of initial hoar crystal greatly.
Hydrophilic antifrosting coating of the present invention after tested, the result shows under certain temperature humidity, can make the frosting time lag more than 3 hours, the frosting degree decreased average is more than 40%.In wall surface temperature＞-10 ℃, in fact can be implemented in frost-free on the cold wall under the condition of relative humidity＜50%, and usability is good repeatedly.Top result has huge application background: in the winter of north cold, when air conditioning machinery was done heating operation, off-premises station (vaporizer) was easy to frosting, caused vaporizer to stop up, and heat exchange efficiency reduces rapidly, causes air conditioning machinery normally not move.This is the basic reason that north common air-conditioning machine in winter can not heating operation.In the winter of north cold, the relative humidity of air generally all smaller (being no more than 50%) so this coating is applied on the air-conditioner outdoor unit heat exchange surface, must effectively suppress the generation of frost, thereby guarantees that air conditioning machinery also can normally move in the winter of cold.
Description of drawings:
The left side scribbles the copper sheet of antifrosting coating at envrionment temperature (T among Fig. 1 embodiment 2
∞) be 15 ℃, cold wall temperature (T
w) be-8.2 ℃, relative humidity () is 40% condition frosting in following 360 minutes contrast photo.The contrast situation of Fig. 2 hydrophilic coating surface and red copper surface frost thickness under different experiment conditions.
(a)T
∞＝16.4℃，T
w＝-8.8℃，＝30％
(b)T
∞＝16.6℃，T
w＝-15.3℃，＝30％
(c)T
∞＝21℃，T
w＝-19.5℃，＝34.5％
(d)T
∞＝15.4℃，T
w＝-8.2℃，＝57％
The white surface temperature of Fig. 3 left side coating and the contrast situation of red copper surface frost surface temperature under different time.
(a) frosting (b) frosting in 30 minutes is 60 minutes
Fig. 4 is at =50%, T
wUnder=-9.3 ℃ of conditions, the frosting photo of the reflection coating repeat performance of different number of days frosting in the time of 60 minutes.
(a) 15 days (b) 40 days (c) is 55 days
Embodiment:
Embodiment 1:
The making step of antifrosting coating is as follows:
1, the making of High hydrophilous resin:
It is as follows that the High hydrophilous resin composition is pressed mass ratio: vinylformic acid 49, acrylamide 10, water 160, potassium hydroxide 20, sodium hydroxide 5, Rocryl 410 7, N, N '-methylene-bisacrylamide 0.002, initiator (ammonium persulphate) 0.04, sodium bisulfite 0.05.
In the reactor that has reflux exchanger, dropping funnel nitrogen conduit, add entry and potassium hydroxide and sodium hydroxide according to above-mentioned prescription, under the condition that feeds nitrogen, add vinylformic acid and N, N '-methylene-bisacrylamide, add Rocryl 410 while stirring, maintain the temperature at 40 ℃.Add acrylamide, divide 4 times and add ammonium persulfate initiator and sodium bisulfite.Be heated to leave standstill under 60 ℃ and carried out polyreaction in 6 hours.Mixture after the polyreaction becomes transparent gel by the white casse gel, vacuum-drying again after the cooling vacuum dehydration, and product obtains High hydrophilous resin through grinding.
2, the making of antifrosting coating: weighing High hydrophilous resin 20 grams, epoxy resin varnish 60 grams, 40 gram glycerol, after auxiliary agent diethylenetriamine 20 grams mix, fully stir, with brush partially mixed liquid is coated on the copper sheet left-hand face that thickness is 6mm, the measurement coat-thickness is 0.3mm.
3, the measure of merit of antifrosting coating is as follows:
1. testing apparatus: refrigerating unit adopts semiconductor temperature difference electricity refrigerator refrigeration, the copper sheet and cold of the semi-conductor that scribble antifrosting coating adopt known means to combine closely, adopt copper-constantan thermocouple to connect the temperature that the HP data collecting instrument is measured red copper surface, the microscopic system of utilizing microscope, pick-up lens, CCD, image collection card, computer, microscopic measurement software to form is carried out white thick measurement, utilizes the TH5102 thermal imaging system of NEC Corporation to measure the surperficial temperature of frost.
2. white thick measuring result:
Accompanying drawing 2 had coating under the different wall temperatures at 30%～50% o'clock for relative humidity remains on and does not have the measurement comparing result of frost thickness on the red copper surface of coating.Result among Fig. 2 (a) shows that when relative humidity was 30% left and right sides, cold wall temperature was in the time of-8.8 ℃, and the undercoat surface did not have frosting in 2 hours, and the thick 0.74mm that reaches of red copper surface frost; Result among Fig. 2 (b) shows that cold wall temperature is in the time of-15.3 ℃, and coatingsurface does not still have frosting, and the white thick of red copper surface is 1.45mm; When cold wall temperature was low to moderate-19.5 ℃, referring to Fig. 2 (c), coatingsurface just began frosting after testing 50 minutes, and frost is thick only to be 1.05mm in the time of 2 hours, and the white thick thick 2.35mm that reaches of red copper surface.Relative humidity among Fig. 2 (d) more greatly 57%, cold wall temperature is at-8.2 ℃, and the result shows that the undercoat surface did not have frosting in 2 hours, and the thick 2.3mm that reaches of red copper surface frost;
3. frosting degree measuring result: according to experimental result calculate adopt this antifrosting coating in humidity greater than 50%, wall temperature is lower than can make frosting degree reduce 34%～41% under-10 ℃ the situation, at relative air humidity less than 50%, wall surface temperature is during greater than-10 ℃, the minimizing of frosting degree is greater than 55%, and the appearance of initial hoar crystal was greater than 3 hours.
Above result shows that the antifrosting coating that is adopted has effectively suppressed white formation, in wall temperature＞-10 ℃, under the condition of relative humidity＜50% to press down white effect especially obvious.
4. surface temperature measurement result:
The purpose of frost prevention is except making white thick attenuate, and the runner of equipment such as the device that avoids evaporating is blocked by the frost layer, the more important thing is the rising significantly of the cold wall surface temperature that prevents that thick frost layer from bringing, and obtains more approaching default temperature.Because coating has thermal resistance, do not add coating so cated surface temperature is higher than in the refrigerating starting stage, but after tested, cated surface temperature is lower than does not have coating after cover the frost layer, so this antifrosting coating has reached the basic goal of frost prevention.Accompanying drawing 3 is at T
∞=26.0 ℃, T
w=-18.3 ℃, under the condition of =60%, adopt TH5102 thermal imaging system coated side of measuring and the white surface temperature comparing result that does not have coated side, can find out obviously that the white surface temperature of wall left-half (scribbling the antifrosting coating part) obviously will be lower than the surface temperature (not being coated with the part of antifrosting coating) of right side frost layer, and left side temperature distribution history big rise and fall, this is because evening appears in the initial hoar crystal of left-hand face, frosting degree is few, and hoar crystal is sparse, and surface temperature that the hoar crystal position occurs will be higher than does not have hoar crystal.
4. repeat performance test result: by bimestrial repeated experiment, find that coating still can keep good frost prevention effect, persistence is (referring to Fig. 4 (a) and (b), (c)) better.
Embodiment 2:
The moiety of High hydrophilous resin sees Table 1, and making processes is with embodiment 1.Weighing High hydrophilous resin 30 grams, epoxy resin varnish 60 grams after 45 gram glycerol are mixed, fully stir, and with brush partially mixed liquid are coated on the copper sheet left-hand face that thickness is 6mm, and the measurement coat-thickness is 0.8mm.Actual test shows is not less than-10 ℃ at cold wall surface temperature, and relative air humidity is no more than in 50% the scope, through 10 hours actual motion, all has tangible hoar crystal to generate less than finding on cold wall.Accompanying drawing 1 is 6 hours captured photos of refrigeration in the once experiment of adopting this antifrosting coating.This embodiment explanation, the coating of being invented can be used for the frost prevention of northern cold winter air-conditioning off-premises station and handle.
Listed embodiment 3,4 in the table 1 respectively, the component of antifrosting coating in 5, wherein the making processes of High hydrophilous resin and antifrosting coating and testing apparatus have listed file names with the component of embodiment 1,2 and the test effect of 5 embodiment with embodiment 1 in the table 1.
Record in test, under the situation of atmospheric moisture lower (＜50%), wall surface temperature higher relatively (＞-10 ℃), the time that initial hoar crystal occurs can be postponed 3 hours at least, frosting degree reduces more than 55%.In the experiment, Measuring Time is the longest to be 10 hours, and " average frosting time of lag " in the table 1 and " the on average minimizing of frosting degree " are the mean value under the situation of atmospheric moisture＜50%, wall surface temperature＞-10 ℃.
Table 1 (unit: g)
| Embodiment 1 | Embodiment 2 | | | Embodiment 5 | ||
| The component of High hydrophilous resin | Water | 160 | 145 | 120 | 130 | 125 |
| | 20 | 50 | 15 | 30 | 30 | |
| Sodium hydroxide | 5 | 0 | 10 | 3 | 3 | |
| Vinylformic acid | 49 | 90 | 55 | 70 | 70 | |
| N, N '-methylene-bisacrylamide | 0.002 | 0.002 | 0.04 | 0.02 | 0 | |
| Rocryl 410 | 7 | 0 | 8 | 10 | 10 | |
| Acrylamide | 10 | 12 | 0 | 15 | 15 | |
| Ammonium persulphate | 0.04 | 0.05 | 0.03 | 0.02 | 0.02 | |
| Sodium bisulfite 0.05 | 0.05 | 0.05 | 0.05 | 0.05 | 0.05 | |
| | 0 | 0 | 0 | 0 | 0.02 |
| | 60 | 60 | 60 | 60 | 60℃ | |
| Polymerization time | 6 hours | 5 hours | 4.5 hour | 4.5 hour | 4.5 hour | |
| Take by weighing the High | 20 | 30 | 60 | 25 | 50 | |
| Coating | Epoxy resin varnish, 60 | Alkyd varnish, 60 | Acrylic resin varnish, 60 | Bakelite varnish, 50 | Alkyd varnish, 50 | |
| | 40 | 45 | 50 | 30 | 50 | |
| Solvent | Pimelinketone, 20 | 200# gasoline, 20 | The propylene glycol butyl ether, 80 | Butylacetate, 30 | Butanone, 60 | |
| Auxiliary agent | Diethylenetriamine, 20 | Do not have | Do not have | Do not have | Do not have | |
| Coat-thickness (mm) | 0.3 | 0.8 | 0.3 | 0.4 | 0.6 | |
| The average retardation frosting time (min) | 465 | 600 | 370 | 400 | 545 | |
| Average frosting degree reduces | 72％ | 100％ | 58％ | 68％ | 80％ | |
Claims (1)
1. hydrophilic antifrosting coating, it is characterized in that comprising 20～60 parts by mass ratio is the High hydrophilous resin of any multipolymer of hydrophilic monomer with acrylate, acrylamide and methacrylic ester, or with arbitrary High hydrophilous resin that is combined as the multipolymer of hydrophilic monomer of acrylate, acrylamide and methacrylic ester, 30～60 parts is the varnish of base-material with in Synolac, Resins, epoxy, acrylic resin, the resol any, 30～50 parts glycerol.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2004101012549A CN1317344C (en) | 2004-12-17 | 2004-12-17 | Hydrophilic antifrosting coating |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2004101012549A CN1317344C (en) | 2004-12-17 | 2004-12-17 | Hydrophilic antifrosting coating |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1632014A CN1632014A (en) | 2005-06-29 |
| CN1317344C true CN1317344C (en) | 2007-05-23 |
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ID=34848064
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2004101012549A Expired - Fee Related CN1317344C (en) | 2004-12-17 | 2004-12-17 | Hydrophilic antifrosting coating |
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Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102007047116A1 (en) * | 2007-10-02 | 2009-04-09 | BSH Bosch und Siemens Hausgeräte GmbH | The refrigerator |
| CN100593557C (en) * | 2008-01-31 | 2010-03-10 | 中国科学院化学研究所 | Rime-proof coating material and method of use thereof |
| CN102408656B (en) * | 2011-08-31 | 2014-03-19 | 山东交通学院 | Anti-freeze nanometer titanium dioxide composite material and application thereof |
| CN102690558B (en) * | 2012-05-31 | 2013-05-29 | 蓬莱蔚阳新材料有限公司 | Process for preparing rust-bearing rust-proof heavy-duty coating |
| CN105001594B (en) * | 2014-04-18 | 2017-12-01 | 中国石油化工股份有限公司 | A kind of seismic physical model material and model |
| CN104356718A (en) * | 2014-12-10 | 2015-02-18 | 李永志 | Hydrophilic fireproof coating |
| CN104356881A (en) * | 2014-12-10 | 2015-02-18 | 李永志 | Hydrophilic anti-mildew coating, |
| CN110093073A (en) * | 2018-01-28 | 2019-08-06 | 姚建珍 | A kind of aqueous coating formulation and preparation method thereof based on Teflon |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5994438A (en) * | 1996-04-06 | 1999-11-30 | Hoeschst Aktiengesellschaft | Pulverulent adhesive composition |
-
2004
- 2004-12-17 CN CNB2004101012549A patent/CN1317344C/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5994438A (en) * | 1996-04-06 | 1999-11-30 | Hoeschst Aktiengesellschaft | Pulverulent adhesive composition |
Non-Patent Citations (3)
| Title |
|---|
| 透明材料的表面改性与防雾防霜性 张刚，崔占臣，杨柏，功能高分子学报，第13卷第1期 2000 * |
| 醇类交联剂对聚丙烯酸钠高吸水性树脂吸水性能的探讨 吴志明，南通职业大学学报，第16卷第4期 2002 * |
| 醇类交联剂对聚丙烯酸钠高吸水性树脂吸水性能的探讨 吴志明，南通职业大学学报，第16卷第4期 2002;透明材料的表面改性与防雾防霜性 张刚，崔占臣，杨柏，功能高分子学报，第13卷第1期 2000 * |
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