A kind of aqueous polyurethane molds soft bubble mould release and preparation method thereofTechnical field
The present invention relates to a kind of mould release and preparation method thereof, be specifically related to a kind of soft bubble of aqueous polyurethane molding with releaseAgent.
Background technology
Polyurethane release agent is divided into external release agent and inner pattern releasing agent applicable two kinds.In order to when processing and forming, goods can be from mouldEasily take out, at one layer of paint, referred to as external release agent that mold surface is coated.Inner pattern releasing agent applicable is added in PU formula, every timeTime molded, move to the interface of foam and mould, thus reach stripping result.
Ideal releasing agent should have preferable heat endurance and chemical stability, does not corrode mould, at mould tableThe most remaining analyte in face, should be able to give the outward appearance that goods are good, do not affect the color and luster of goods, cohesive, by paint ability etc., to the greatest extent may be usedThe mold cleaning time can be reduced；And nontoxic, safety, it is simple to operation, cost is relatively low.
For various reasons, inner pattern releasing agent applicable uses seldom, and what current polyurethane industries among others was widely used remains the outer demouldingAgent.External release agent is typically made up of medium and demoulding active material.Medium is usually organic solvent or water, demoulding active materialCommon are silicone oil, wax and grease etc..Medium in used external release agent is usually organic solvent, such as halogenated hydrocarbons and aliphatic hydrocarbonDeng, owing to organic solvent used is the most poisonous or flammable, threaten safety, and pollute environment；Use water as solvent then to lack without thesePoint, therefore the water based mold release agent with water as medium is greatly paid close attention to by people.But existing aqueous mould release all contains organic moltenAgent, it is impossible to use deionized water to disperse completely；And existing aqueous mould release scarcely shelf-stable, solid content are relatively low,Poor with the cohesive force of metal.
Summary of the invention
For solving the not shelf-stable of existing aqueous mould release existence, the relatively low poor adhesive force etc. with metal of solid content is askedTopic, the invention discloses a kind of water type polyurethane and molds soft bubble mould release, gluing of its solid content height, good film-forming property and metalKnot power is good.
For reaching above-mentioned purpose, the technical scheme is that, a kind of water type polyurethane molds soft bubble mould release, with weightAmount percentages, described aqueous polyurethane molds soft bubble mould release and includes following composition: PEPA 0 ~ 40 part, polyethers is manyUnit's alcohol 10 ~ 60 parts, isocyanates 15 ~ 30 parts, dihydromethyl propionic acid 1 ~ 8 part, triethylamine 1 ~ 7 part, amine chainextender 0.05 ~ 0.15Part, catalyst 0 ~ 0.15 part, defoamer 0.05 ~ 0.15, wax class 30 ~ 80 parts, deionized water 50 ~ 200 parts；
Described amine chainextender is ethylenediamine；
Described catalyst is T-120 or T12；
Described defoamer is T-7551 or BYK-024；
Described wax class is Tissuemat E or microwax.
Wherein, described PEPA is 0 ~ 1 with the mass ratio of PPG.
Wherein, described PEPA is PBA2000.
Wherein, described PPG is the combination of one or more in N220, KGF2000MD or N330.
Wherein, described wax class is Tissuemat E, and temperature tolerance is higher than 70 DEG C；Or microwax, temperature tolerance is higher than 65 DEG C.
Wherein, described isocyanates is IPDI or HDI；Its isocyanate index (NCO/OH molar ratio) is 1.1 ~1.4。
The present invention also provides for a kind of aqueous polyurethane and molds the preparation method of soft bubble mould release, and described preparation method includesFollowing steps:
A, Starting Material Polyester polyalcohol, PPG, dihydromethyl propionic acid, wax class and chain extender are subtracted in 110 ~ 120 DEG CPressure stirring dehydration；
B, in step a system add isocyanates, under catalyst, carry out prepolymerization reaction and hydrophilic chain extending reaction；
C, the base polyurethane prepolymer for use as that deionized water solution and step b dissolved with triethylamine prepares is neutralized, at a high speed pointDissipate emulsification；
D, in step c gained system, add amine chainextender and organotin catalysts, after dispersion 1h, add defoamer and continueDispersion 10min, i.e. can get aqueous polyurethane and molds soft bubble mould release.
Wherein, the PEPA in described step a is 0 ~ 1.0 with the mass ratio of PPG；Described wax class isThe 30 ~ 80% of gross mass, heating-up temperature is 105 ~ 120oC, vacuum is 0.08 ~ 0.1Ma, and dewatering time is 2 ~ 3 h.
Wherein, in described step b catalyst amount be performed polymer total amount ten thousand/~ 5/10000ths；Described isocyanic acidThe isocyanate index of ester is 1.1 ~ 1.4；Described prepolymerization reaction temperature is 75 ~ 95oC, the reaction time is 1 ~ 3 h.
Wherein.In described step c triethylamine consumption is performed polymer total amount 1% ~ 2%；Described rate of dispersion is 600 ~2000 r/min；The emulsion dispersion time is 0.5 ~ 2 h.
Compared with prior art, the method have the advantages that
1, the aqueous polyurethane soft bubble mould release storage stability of molding of the present invention is good, and solid content is higher；
2, the aqueous polyurethane of the present invention molds the good film-forming property of soft bubble mould release, with the cohesive force of metal grinding tool relativelyGood, substantially increase release times；
3, the preparation method technique of the present invention is simple, and cost is relatively low, without any organic solvent, uses deionized water to carry outDispersion, preparation technology low-carbon environment-friendly.
Detailed description of the invention
Below in conjunction with specific embodiment, the present invention is expanded on further.Should be understood that these embodiments are merely to illustrate the present inventionRather than restriction the scope of the present invention.In addition, it is to be understood that after having read present disclosure, those skilled in the art canTo make various changes or modifications the present invention, these equivalent form of values fall within limited range of the present invention equally.
Embodiment 1,
Weigh following raw material:
PEPA PBA2000 20g
PPG N220 80g
Isocyanates IPDI 33.5g
Dihydromethyl propionic acid DMPA 6g
Triethylamine 3g
Ethylenediamine 0.1g
Catalyst T-120 0.03g
Tissuemat E 45g
Deionized water 187g
T-7551 0.2g
Preparation process:
Step a, polyester PBA2000, PPG N220, DMPA and Tissuemat E dehydration
In being dried the clean 500mL there-necked flask equipped with agitator and thermometer, add PBA2000, N220, DMPAAnd Tissuemat E, in 110 DEG C, decompression dehydration 2h under 0.08MPa vacuum；
Step b, prepolymerization reaction
It is cooled to 60oC, is slowly added to 33.5g IPDI, T-120 mono-in flask, measures in performed polymer after reaction 2hThe content of-NCO base, until close to theoretical value；
Step c, prepares dispersion
The base polyurethane prepolymer for use as that deionized water 187g and step b dissolved with triethylamine prepares is neutralized, high speed dispersionEmulsification.
Step d, chain extension froth breaking
In step c gained system, add amine chainextender and organotin catalysts stannous octoate, after dispersion 1h, add froth breakingAgent T-7551 continues dispersion 10min, i.e. can get aqueous polyurethane and molds soft bubble mould release.
Embodiment 2,
Weigh following raw material:
PBA2000 10g
KGF2000MD 80g
N330 20g
HDI 35.5g
DMPA 8g
Tissuemat E 80g
Deionized water 210g
Triethylamine 7g
Ethylenediamine 0.12g
T-120 0.03g
BYK-024 0.25g
Step a, polyester, PPG, DMPA and Tissuemat E dehydration
In being dried the clean 500mL there-necked flask equipped with agitator and thermometer, addition PBA2000,KGF2000MD, N330, DMPA and Tissuemat E 80g, in 110 DEG C, decompression dehydration 2h under 0.08MPa vacuum；
Step b, prepolymerization reaction
It is cooled to 60oC, is slowly added to 35.5g HDI, T-120 mono-in flask, measures in performed polymer after reaction 2hThe content of-NCO base, until close to theoretical value；
Step c, prepares dispersion
Base polyurethane prepolymer for use as prepared with step b for deionized water solution 210g dissolved with triethylamine is neutralized, at a high speedDispersion and emulsion.
Step d, chain extension froth breaking
In step c gained system, add amine chainextender and organotin catalysts stannous octoate, after dispersion 1h, add froth breakingAgent BYK-024 continues dispersion 10min, i.e. can get aqueous polyurethane and molds soft bubble mould release.
Embodiment 3,
(1) mensuration of mould release solid content
Measure by GBl725-79 regulation.Take dry surface plate and claim quality m, then weigh m with Subtraction method0=1.5-2.0gPolymer emulsion is laid in surface plate, puts in baking oven 60oC is dried 24h, and taking-up is cooled to room temperature and weighs, places into baking ovenBeing dried until weighing difference to be less than 0.01g, obtaining last stabilised quality is m1。
Solid content=m1-m/m0×100%
After tested, in embodiment 1, the solid content of polyaminoester emulsion is 50%.
(2) mensuration of bin stability
In the colorimetric pool of band plug, add the made mould release of 50mL embodiment 1, be positioned over 70 ± 3 DEG C of thermostatic drying chambersMiddle 3h, takes out and is cooled to room temperature (15 DEG C～35 DEG C), places 3h, is placed in 24h in the low temperature refrigerator of-12 ± 3 DEG C the most again,Take out and stand to room temperature, evaluate after 1h.Given formula not layering, phase transformation, gluey phenomenon.
(3) mensuration of PH value
Made for embodiment 1 mould release dilution 5 times is placed in measuring cup, measures with PHS-25 display precise PH meter,Measured value is 7.0～8.0.
(4) defoaming test
20% embodiment 1 made mould release dilution is poured in 100mL band plug graduated cylinder, make liquid level at 70m l,Building lid, fluctuate 1 minute, shake frequency is 120 times/min, the most at room temperature stands 10 minutes, observes liquidFace resid vol is 5mL.
(5) viscosity test
It is diluted to mould release prepared by embodiment 1 spray multiple, is transferred in measuring cup, measures with viscosity determinatorIts viscosity is 100 mPa.s.
It is good that the aqueous polyurethane of the present invention molds soft bubble mould release storage stability, and solid content is higher；Good film-forming property, withThe cohesive force of metal grinding tool is preferable, substantially increases release times.The preparation method technique of the present invention is simple, and cost is relatively low, noContaining any organic solvent, preparation technology low-carbon environment-friendly.
It is more than the description to the embodiment of the present invention, by the described above to the disclosed embodiments, makes this area specialIndustry technical staff is capable of or uses the present invention.Those skilled in the art are come by the multiple amendment to these embodimentsSaying and will be apparent from, generic principles defined herein can be in the situation without departing from the spirit or scope of the present inventionUnder, realize in other embodiments.Therefore, the present invention is not intended to be limited to the embodiments shown herein, and is intended to symbolClose the widest scope consistent with principles disclosed herein and features of novelty.