Summary of the invention
The object of the present invention is to provide a kind of water-based cooling coating and preparation method thereof, to overcome deficiency of the prior art.
For achieving the above object, present invention employs following technical scheme:
A kind of water-based cooling coating, comprises the aqueous dispersion containing matrix resin, the boron nitride composite granule of nano-carbon material parcel and can the subsidiary material that add of selectivity;
Wherein, the nano-carbon material that the boron nitride composite granule that described nano-carbon material wraps up comprises 70-99.9wt% boron nitride and is coated in boron nitride, described nano-carbon material comprises carbon nanotube and/or grapheme material.
Further, the particle diameter of described boron nitride is preferably 500nm-50 μm.
Further, described carbon nanotube diameter is preferably 0.4 nm-100 nm, and length is preferably 50 nm-25 μm.
Further, the thickness of described grapheme material is preferably 0.34 nm-10 nm, and mean diameter is preferably 500 nm-100 μm.
Further, described subsidiary material can include but not limited to filler, dispersion agent or auxiliary agent, and described auxiliary agent can include but not limited to defoamer, flow agent, film coalescence aid or thickening material.
As one of comparatively preferred embodiment, described water-based cooling coating comprises the following component according to weight percent meter: boron nitride composite granule 0.1-5%, nano-carbon material 0.1-5%, the dispersion agent 0.1-5% of the aqueous dispersion 20-40% containing matrix resin, nano-carbon material parcel, auxiliary agent 0.5-7%.
Preferably, the described aqueous dispersion containing matrix resin comprises modified aqueous epoxy resin.
Further, described modified aqueous epoxy resin can be selected from but be not limited to any one or the two or more combinations in the emulsion that acrylic modified epoxy resin aqueous dispersions, directly emulsion epoxy resin water-based emulsion or the direct emulsification of modified aqueous epoxy resin formed.
Wherein, described dispersion agent can be selected from but be not limited to Walocel MT 20.000PV, sodium carboxymethylcellulose pyce, ethyl cellulose, methylcellulose gum, carboxymethyl cellulose, Vltra tears, water-soluble polypropylene acid, polyvinylpyrrolidone, polyvinyl alcohol, Triton, commercial carbon blacks dispersion treating compound as any one in German Bi Ke BYK191, BYK181, BYK180 or two or more combinations.
Further, described water-based cooling coating also comprises the solidifying agent that addition is the described aqueous dispersion body weight 1-10% containing matrix resin, and described solidifying agent can be selected from but be not limited to amino resin curing agents, masked isocyanate or anhydride curing agent.
A kind of preparation method of water-based cooling coating, comprise: by the aqueous dispersion containing matrix resin with can subsidiary material more than the grinding distribution 3h that adds of selectivity, form dispersed paste, boron nitride composite granule then to major general's nano-carbon material parcel slowly adds described dispersed paste, more than 20min is stirred with the speed of more than 500rpm, then leave standstill froth breaking, obtain water-based cooling coating.
A preparation method for water-based cooling coating, comprising:
(1) by modified aqueous epoxy resin, dispersion agent, defoamer and nano-carbon material grinding distribution 3-48h, nano-sized carbon dispersed paste is obtained;
(2) under the condition accompanying by stirring, the boron nitride composite granule of auxiliary agent, nano-carbon material parcel is slowly added in nano-sized carbon dispersed paste, stirs 20min-2h with the speed of 500-5000rpm;
(3) obtain in mixture to step (2) and add water, mixture viscosity is adjusted to setting range, then leave standstill froth breaking, obtain described water-based cooling coating.
Water-based cooling coating of the present invention can adopt the technique film forming arbitrarily such as roller coating, spraying, spin coating, and its condition of cure is preferably: 100-200 DEG C, 5-40min.
Compared with prior art, advantage of the present invention comprises:
(1) heat radiation coating is prepared in boron nitride and the interpolation of nano-carbon material compound, can play the advantage of its high heat conductance and high infrared radiance simultaneously, make coating have superior heat dispersion;
(2) using nano-carbon material parcel boron nitride composite granule as heat conductive filler, nano-carbon material and boron nitride are combined closely by chemistry or non-bonding effect, reduces interface resistance, form outstanding passage of heat;
(3) compound of micro-nano-scale particle is added, and is conducive in coating, form more stable dispersion system, improves the dispersiveness of nano-carbon material in coating;
(4) full water-based system of the present invention has the film forming such as safety and environmental protection, easy construction advantage, has range of application widely.
Embodiment
One aspect of the present invention provides a kind of water-based cooling coating, it is mainly using the boron nitride composite granule of nano-carbon material parcel as heat-conductive coating filler, there is micro-nano-scale conductive structure, the performance advantage of nano-carbon material and boron nitride can be given full play to, there is the high-performance of high heat conductance and high infrared radiance.
Further, this water-based cooling coating comprises the aqueous dispersion containing matrix resin, nano-carbon material parcel boron nitride composite granule and can selectivity add subsidiary material;
Wherein, the nano-carbon material that the boron nitride composite granule that described nano-carbon material wraps up comprises 90-99.9wt% boron nitride and is coated in boron nitride.
Described nano-carbon material can adopt the carbon nanotube, grapheme material etc. addressed above.
Wherein, described carbon nanotube can select single wall and/or multi-walled carbon nano-tubes, and described grapheme material can select Graphene and/or graphene microchip.
Described graphene microchip (Graphene Nanoplatelets or Graphene Nanosheets) refers to that carbon-coating number is more than 10 layers, the ultra-thin Graphene stratiform accumulation body of thickness in 5-100 nanometer range.
Aforementioned boron nitride preferably adopts median size at the hexagonal system boron nitride particle of 500 nm-150 μm.
Aforementioned subsidiary material can include but not limited to filler, dispersion agent, auxiliary agent, solidifying agent etc.
Particularly, wherein filler preferably adopts nano-carbon material, but other heat conductive filler that industry also can be selected known.
In a comparatively typical embodiment, described water-based cooling coating can comprise the following component according to weight percent meter: boron nitride composite granule 0.1-5%, nano-carbon material 0.1-5%, the dispersion agent 0.1-5% of modified aqueous epoxy resin 20-40%, nano-carbon material parcel, auxiliary agent 0.5-7%.
Wherein, aforesaid modified aqueous epoxy resin refers to that epoxy resin is scattered in the emulsion, water dispersion or the aqueous solution that are formed in aqueous phase with particulate, drop or colloidal form, it can be selected from but be not limited to aforesaid all kinds, and it can adopt the preparations such as direct method, phase inversion, self-emulsification and solidifying agent emulsion process.
Aforementioned modified aqueous epoxy resins, dispersion agent etc. also all obtain by commercially available approach, and such as, foregoing dispersant can select BYK191, BYK181, BYK180 of German Bi Ke etc.
Consult shown in Fig. 1, when using carbon nanotube (CNT) as nano-carbon material, the boron nitride composite granule (BNCNT) of the nano-carbon material parcel that it is formed can form cross-linked network with the carbon nanotube be dispersed in coating, and then constructs efficient passage of heat.
In one embodiment, the method preparing aforementioned nano-sized carbon parcel boron nitride composite granule can comprise: be scattered in water by carboxylated nano-carbon material, and under the condition accompanying by stirring, add amino functional boron nitride powder in batches, fully be uniformly mixed rear filtration, by much filtrate vacuum-drying, obtain described nano-sized carbon parcel boron nitride composite granule.
In an exemplary embodiments, the preparation method of this nano-sized carbon parcel boron nitride composite granule can comprise the steps:
(1) nano-carbon material raw material being added concentration is in the salpeter solution of 2-8 M, filters, by much filtrate washing to neutral, collect for subsequent use after 100-140 DEG C of backflow 1-24 h;
(2) be dispersed in anhydrous solvent by boron nitride powder, add the amino coupling agent accounting for boron nitride powder body weight 1-30%, mix and blend 1-24h, stir 30min-1h subsequently, then filter at 70-100 DEG C, collection much filtrate is for subsequent use;
(3) step (1) obtained product is dispersed in water, in high-speed stirring, add step (2) obtained product gradually, filter after mix and blend 10min-2h, collect much filtrate, and at 60-100 DEG C of vacuum-drying 1-6h, obtain nano-carbon material parcel boron nitride composite granule;
Further, abovementioned steps (2)-(3) are recycled repetition more than 1 time.
Wherein, adopt graphene oxide as nano-carbon material raw material, then after acquisition composite granule, also need to carry out graphene oxide reduction treatment relating operation, the graphene oxide reducing process wherein adopted comprises high-temperature hot reduction, microwave reduction, reductive agent gas phase or liquid-phase reduction technique, and the reductive agent wherein adopted comprises hydrogen, sodium borohydride, hydrazine hydrate, xitix, citric acid, hydroiodic acid HI or Hydrogen bromide.
Aforementioned anhydrous solvent can be selected from but be not limited to any one or the two or more combinations in dehydrated alcohol, propyl carbinol, Virahol, toluene, dimethylbenzene, benzene, chloroform, methylene dichloride and acetone.
Aforementioned amino coupling agent can be selected from but be not limited to any one or the two or more combinations in γ-aminopropyl triethoxysilane (KH550), γ-aminopropyltrimethoxysilane (KH540), N-β-(aminoethyl)-γ-aminopropyltriethoxy dimethoxysilane (KH602), N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane (KH900), γ aminopropyltriethoxy diethoxy silane (KH902).
Another aspect of the present invention provides a kind of preparation method of water-based cooling coating, it comprises: by the aqueous dispersion containing matrix resin with can the subsidiary material grinding distribution that adds of selectivity, form dispersed paste, boron nitride composite granule then to major general's nano-carbon material parcel slowly adds described dispersed paste, leave standstill froth breaking after high-speed stirring, obtain target product.
In an exemplary embodiments, the preparation method of this water-based cooling coating can comprise:
(1) by modified aqueous epoxy resin, dispersion agent, defoamer and nano-carbon material grinding distribution 3-48h, nano-sized carbon dispersed paste is obtained;
(2) under the condition accompanying by stirring, the boron nitride composite granule of auxiliary agent, nano-carbon material parcel is slowly added in nano-sized carbon dispersed paste, stirs 20min-2h with the speed of 500-5000rpm;
(3) obtain in mixture to step (2) and add water, mixture viscosity is adjusted to setting range, then leave standstill froth breaking, obtain described water-based cooling coating.
Another aspect of the present invention provides the application of aforementioned water-based cooling coating, can comprise: adopt any technique such as roller coating, spraying, spin coating by described coating film forming, solidification, obtain required coating.Comparatively preferred, the condition of cure of described coating can be: 100-200 DEG C, 5-40min.
The present invention is by being assembled in boron nitride particle surface by part nano-carbon material parcel, form stable nucleocapsid structure and heat conduction network more closely, significantly can reduce the interface resistance of nano-carbon material and boron nitride particle or other thermal conductive ceramic phase, play nano-carbon material and the high thermal conductance of boron nitride and the advantage of high infrared radiation coefficient simultaneously, and also can with all the other the thermally conductive material networks in coating, the such as efficient passage of heat of nano-carbon material network struction, thus significantly improve the heat conductivility of coating and mechanical property (such as, can film toughness be improved) the various metal needing to strengthen ir radiation heat radiation can be widely used in, pottery, plastic-substrates, and there is easy construction, the advantages such as safety and environmental protection, show very important marketable value.
Below in conjunction with some embodiments and accompanying drawing, technical scheme of the present invention is further described.
embodiment 1:
Raw material (if following not specified, all referring to weight percent) is taken by following formula:
Acrylic modified waterborne epoxy resin 20%;
Auxiliary agent 3%;
The boron nitride composite granule 1% of carbon nanotube parcel;
Carbon nanotube 1%;
Polyacrylic acid grind resin 2%
Water surplus.Aforesaid builders comprises the defoamer, flow agent, solubility promoter etc. that industry is commonly used.
With acrylic modified epoxy resin aqueous dispersions for matrix resin, by metering than calculating proportioning, the grinding distribution in grinding distribution machine such as matrix resin, carbon nanotube, polyacrylic acid grind resin, defoamer BYK021 is prepared nano carbon material dispersed paste in 8 hours.Subsequently under high speed dispersor stirs, the boron nitride composite granule of residue auxiliary agent, carbon nanotube parcel is slowly added in carbon nanotube dispersed slurry, stirring velocity 1000 revs/min, churning time 30 minutes.Finally excess water is added, be adjusted to appropriate viscosity, after leaving standstill froth breaking, namely obtain water-based cooling coating.Adopt spraying coating process film forming, condition of cure be 180 degree toast 5 minutes coating film forming after infrared radiation coefficient 0.95, thermal conductivity 0.85 W/m K, hardness 2H.
embodiment 2:the difference of the present embodiment and embodiment 1 is, carbon nanotube addition is 2%, the infrared radiation coefficient 0.95 after coating film forming, thermal conductivity 1.2 W/m K, hardness 2H.
embodiment 3:the difference of the present embodiment and embodiment 1 is, carbon nanotube addition is 3%, the infrared radiation coefficient 0.96 after coating film forming, thermal conductivity 1.54 W/m K, hardness 2H.。
embodiment 4:the difference of the present embodiment and embodiment 1 is, nano-carbon material is Graphene, the infrared radiation coefficient 0.95 after coating film forming, thermal conductivity 0.9 W/m K, hardness 2H.
embodiment 5:the difference of the present embodiment and embodiment 4 is, Graphene addition is 2%, the infrared radiation coefficient 0.95 after coating film forming, thermal conductivity 1.24 W/m K, hardness 2H.
embodiment 6: the difference of the present embodiment and embodiment 1 is, matrix resin is emulsion epoxy resin water-based emulsion, the infrared radiation coefficient 0.95 after coating film forming, thermal conductivity 0.92 W/m K, hardness 2H.
embodiment 7: the difference of the present embodiment and embodiment 1 is, adds 2% amino resin curing agents in addition in coating, the infrared radiation coefficient 0.95 after coating film forming, thermal conductivity 0.90 W/m K, hardness 4H.
More than illustrate, and the embodiment shown on drawing, the design philosophy surely of the present invention that is limited can not be resolved.Hold in technical field of the present invention identical know the knowledgeable can by technical thought of the present invention with various form improvement change, such improvement and change are interpreted as belonging in protection scope of the present invention.