Summary of the invention
Embodiment of the invention technical problem to be solved is, good scratch resistance aqueous polyurethane coating of a kind of ductility and preparation method thereof is provided.
In order to solve the problems of the technologies described above, the embodiment of the invention provides a kind of scratch resistance aqueous polyurethane coating, and wherein, the raw material of said coating comprises following weight part: water-borne acrylic resin: 20-50; Solidifying agent: 10-30; Nano-calcium carbonate: 10-25; Aqueous polyurethane: 20-50; Reactive organosilicon: 1-5; Cosolvent: 1-3.
Said water-borne acrylic resin is the vinyl resin of hydroxyl, and solid content is 40%-70%, and particle diameter is 60-100nm.
Said solidifying agent is a POLYMETHYLENE POLYPHENYLISOCYANATE, and-NCO content is 15%-20%; Said aqueous polyurethane is end-blocked aqueous polyurethane, and solid content is 10%-15%; Said reactive organosilicon is that hydroxy-end capped linearity can be reacted siloxanes; Said cosolvent comprises any or the combination in ethylene glycol mono-ether, Ucar 35 monoether, Virahol, butanols and the butanone.
Correspondingly, the embodiment of the invention also provides a kind of preparation method of scratch resistance aqueous polyurethane coating, and wherein, the raw material of said coating comprises following weight part: water-borne acrylic resin: 20-50; Solidifying agent: 10-30; Nano-calcium carbonate: 10-25; Aqueous polyurethane: 20-50; Reactive organosilicon: 1-5; Cosolvent: 1-3; The preparation method of said coating may further comprise the steps:
(1) said cosolvent is added in the said reactive organosilicon, obtain organic silicon solution;
(2) said water-borne acrylic resin is mixed with organic silicon solution and the solidifying agent that nano-calcium carbonate, aqueous polyurethane, step (1) obtain successively, obtain coating.
Preferably, said water-borne acrylic resin is the vinyl resin of hydroxyl, and solid content is 40%-70%, and particle diameter is 60-100nm; Said solidifying agent is a POLYMETHYLENE POLYPHENYLISOCYANATE, and-NCO content is 15%-20%; Said aqueous polyurethane is end-blocked aqueous polyurethane, and solid content is 10%-15%; Said reactive organosilicon is that hydroxy-end capped linearity can be reacted siloxanes; Said cosolvent comprises any or the combination in ethylene glycol mono-ether, Ucar 35 monoether, Virahol, butanols and the butanone.
Select for use nano-calcium carbonate as mineral filler among the present invention, nano-calcium carbonate joins in the waterborne polymeric, is uniformly dispersed easily, can produce nano effect better.In addition, the Mohs' hardness of nano-calcium carbonate is 3, and is bigger than polymkeric substance, can improve polymkeric substance hardness, realizes scrath resistance.In the present invention, adopt mixing of hard component and soft component, make coating realize hard and tough performance, wherein soft component be end-block aqueous polyurethane, hard component is a water-borne acrylic resin.In the making processes, water-borne acrylic resin and nano-calcium carbonate, aqueous polyurethane, organic silicon solution and solidifying agent POLYMETHYLENE POLYPHENYLISOCYANATE are stirred.Since end-block aqueous polyurethane can not react with POLYMETHYLENE POLYPHENYLISOCYANATE, the soft chain segment of its molecule itself can be good at improving the toughness of coating; Simultaneously, the organosilicon in the component can be participated in polymer reaction, makes the reaction of part segment and polymer segment to improve the polymer surfaces performance, and performances such as sticking power, hardness, curing speed are improved.After stirring coating is applied at product surface; Be cured through 70 ℃ drying oven at last; As solidifying agent, film by the tough and tensile double-component acrylic acid polyurethane that when film forming is solidified, is converted into water resisting property with POLYMETHYLENE POLYPHENYLISOCYANATE for wherein hard component water-borne acrylic resin.It should be noted that reactive organosilicon need dissolve with cosolvent before use, make reactive organosilicon and water miscible.
Therefore embodiment of the present invention has scratch resistance and good ductility filming of substrate surface formation behind the paint solidification, and appearance is lubricated.Simultaneously according to the difference of coating purposes, the hardness of adjustable coating and tough sex ratio, use range is extensive, and cost is low.
Embodiment
For making the object of the invention, technical scheme and advantage clearer, will do to describe in detail further to the present invention below.
A kind of scratch resistance aqueous polyurethane coating is characterized in that the raw material of said coating comprises following weight part: water-borne acrylic resin: 20-50; Solidifying agent: 10-30; Nano-calcium carbonate: 10-25; Aqueous polyurethane: 20-50; Reactive organosilicon: 1-5; Cosolvent: 1-3.
Need to prove that the present invention adopts nano-calcium carbonate as mineral filler.
In addition, this coating adopts mixing of hard component and soft component, and to realize hard and tough performance, as solidifying agent, film by the tough and tensile double-component acrylic acid polyurethane that when film forming is solidified, is converted into water resisting property with POLYMETHYLENE POLYPHENYLISOCYANATE for wherein hard component water-borne acrylic resin; Soft component be end-block aqueous polyurethane, the soft chain segment in its molecule can be good at improving the toughness of coating.Purposes according to coating is different, can change to realize hardness and flexible through the ratio of said water-borne acrylic resin of allotment and said aqueous polyurethane, enlarges the use range of coating.
Further; Reactive organosilicon in said coating can be participated in polymer reaction; Make part segment and polymer segment react; Be intertwined with the polymer coating film molecular chain, when improving the polymer surfaces performance, a large amount of migrations can not take place, make performances such as sticking power, hardness, curing speed improve.
Preferably, said water-borne acrylic resin is the vinyl resin of hydroxyl, and solid content is 40%-70%, and particle diameter is 60-100nm.
Need to prove that said water-borne acrylic resin is polymerized by the acrylic ester monomer of hydroxy functional groups and the acrylic ester monomer of hydroxy functional groups not.Further, the acrylic ester monomer of said hydroxy functional groups is selected from any or the combination in Hydroxyethyl acrylate, Propylene glycol monoacrylate, Rocryl 400, methylacrylic acid hydroxyl propyl ester and the methylacrylic acid hydroxy butyl ester; The acrylic ester monomer of said not hydroxy functional groups is selected from any or the combination in methyl acrylate, ethyl propenoate, Bing Xisuandingzhi, TEB 3K, n-BMA and the Jia Jibingxisuanyizhi.
Preferably, said solidifying agent is a POLYMETHYLENE POLYPHENYLISOCYANATE, and-NCO content is 15%-20%.
Need to prove that said solidifying agent must just add before applying use.
Preferably, said aqueous polyurethane is end-blocked aqueous polyurethane, and solid content is 10%-15%.
Need to prove that said end-blocked aqueous polyurethane is the soft component of coating.Because end group do not contain-OH and-COOH isoreactivity group, therefore can not react, only as a kind of flexible blend components that provides with POLYMETHYLENE POLYPHENYLISOCYANATE.
Preferably, said reactive organosilicon is that hydroxy-end capped linearity can be reacted siloxanes.Further, said cosolvent comprises any or the combination in ethylene glycol mono-ether, Ucar 35 monoether, Virahol, butanols and the butanone.
Need to prove that said reactive organosilicon must be to follow polymer reaction, a large amount of migrations can not take place for a long time, little to the complete processing influence.In addition, said reactive organosilicon need dissolve with small amounts of co-solvents before use, makes the reactive organosilicon can be miscible with water.
Preferably, said coating can also add auxiliary agent; Said auxiliary agent is one or more in thinner, flow agent, skimmer, the catalyzer.
Need to prove that said auxiliary agent is not a necessary component of the present invention, can improve speed of response and effect better but in reaction process, correspondingly add auxiliary agent.Further, said auxiliary agent can not react with-NCO group.
Come to describe in more detail the present invention through embodiment below.
Embodiment 1
Present embodiment is used for explaining preparation method for coating of the present invention.
The step of making coating is:
(1) 3 parts of organic silicons are answered in negate, and add 2 parts of cosolvent Virahols to it, after the dissolving of question response organic silicon, obtain reactive organic silicon solution, and are subsequent use;
(2) the water intaking based acrylic resin stirs for 35 parts, adds 17 parts of nano-calcium carbonates, 35 parts of aqueous polyurethanes, said organic silicon solution and solidifying agent POLYMETHYLENE POLYPHENYLISOCYANATE successively to said water-borne acrylic resin while stirring and mixes for 20 parts, obtains coating;
(3) said coating is coated in product surface;
(4) the said product that scribbles coating being sent into 70 ℃ drying oven is cured.
This paint adhesion is strong, and paint film appearance is plentiful, and is smooth bright and clean, the paint film good toughness, and scratch resistance is high, has satisfactory stability property.
Embodiment 2
In the step (2) of embodiment 1, increase a small amount of flow agent, skimmer and catalyzer, all the other are identical with the method for embodiment 1.
This coating effect and embodiment 1 are basic identical, but owing to added corresponding adjuvants, speed of response is faster.
Embodiment 3
Part components contents among the embodiment 1 is changed into: water-borne acrylic resin: 50 parts; Solidifying agent POLYMETHYLENE POLYPHENYLISOCYANATE: 30 parts; Nano-calcium carbonate: 25 parts; Aqueous polyurethane: 20 parts; Reactive organosilicon: 5 parts; 3 parts of cosolvent Virahols; All the other are identical with the method for embodiment 1.
This paint adhesion is strong, and paint film appearance is plentiful, and is smooth bright and clean, and wherein hardness is particularly outstanding, has satisfactory stability property.Be applicable to the hardness requirement high product.
Embodiment 4
Part components contents among the embodiment 1 is changed into: water-borne acrylic resin: 50 parts; Solidifying agent POLYMETHYLENE POLYPHENYLISOCYANATE: 30 parts; Nano-calcium carbonate: 10 parts; Aqueous polyurethane: 20 parts; Reactive organosilicon: 1 part; 1 part of cosolvent Virahol; All the other are identical with the method for embodiment 1.
This paint adhesion is strong, and paint film appearance is plentiful, and is smooth bright and clean, and hardness is high, has satisfactory stability property.
Embodiment 5
Part components contents among the embodiment 1 is changed into: water-borne acrylic resin: 20 parts; Solidifying agent POLYMETHYLENE POLYPHENYLISOCYANATE: 13 parts; Nano-calcium carbonate: 20 parts; Aqueous polyurethane: 50 parts; Reactive organosilicon: 5 parts; 3 parts of cosolvent Virahols; All the other are identical with the method for embodiment 1.
This paint adhesion is strong, and paint film appearance is plentiful, and is smooth bright and clean, and ductility is good, stable in properties property.
Embodiment 6
Part components contents among the embodiment 1 is changed into: water-borne acrylic resin: 20 parts; Solidifying agent POLYMETHYLENE POLYPHENYLISOCYANATE: 10 parts; Nano-calcium carbonate: 10 parts; Aqueous polyurethane: 50 parts; Reactive organosilicon: 1 part; 1 part of cosolvent Virahol; All the other are identical with the method for embodiment 1.
This paint adhesion is strong, and paint film appearance is plentiful, and is smooth bright and clean, and wherein ductility is particularly outstanding, has satisfactory stability property.Be applicable to the toughness reguirements high product.
Performance test
The sticking power test:
The method of inspection: GB/T9286-1998;
Quality index: being divided into is six grades, and 0,1,2 grade is qualified.3,4,5 grades is defective.
The impact resistance performance test:
The method of inspection: GB/T1732-1993;
Quality index: do not cause single ㎝ of the high degree of paint film destructive with 1000g ± 1g weight vertical drop) be index, it is qualified that the multilayer thickness requires >=30 ㎏ ㎝.
Hardness test:
The method of inspection: GB/T6739-96;
Quality index: hardness order from high in the end is: 9H>8H>6H>5H>4H>3H>2H>H>F>HB>B>2B>3B>4B>5B>6B.
The ductility test:
The method of inspection: range estimation;
Quality index: paint film does not ftracture to qualified.
Paint film appearance:
The method of inspection: range estimation;
Quality index: paint film smooth smooth be qualified.
The coating that embodiment 1-6 is obtained carries out corresponding performance test according to the method described above, and the result who records lists in the table 1.
By on can know that embodiment of the present invention has scratch resistance and good ductility filming of forming of substrate surface behind the paint solidification, appearance is lubricated.Simultaneously according to the difference of coating purposes, the hardness of adjustable coating and tough sex ratio, use range is extensive, and cost is low.
The above is a preferred implementation of the present invention; Should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the principle of the invention; Can also make some improvement and retouching, these improvement and retouching also are regarded as protection scope of the present invention.