CN103302234B - A kind of amine method cold core box binder of the easy demoulding - Google Patents
A kind of amine method cold core box binder of the easy demoulding Download PDFInfo
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- CN103302234B CN103302234B CN201310232614.8A CN201310232614A CN103302234B CN 103302234 B CN103302234 B CN 103302234B CN 201310232614 A CN201310232614 A CN 201310232614A CN 103302234 B CN103302234 B CN 103302234B
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Abstract
The present invention proposes a kind of amine method cold core box binder of the easy demoulding, it comprises the compound releasing agent be made up of alkene releasing agent and ester class releasing agent, described alkene releasing agent is C12-C16 monoolefine, and described ester class releasing agent is one or more in the group be made up of the single methanol ester of C12-C18 alkanoic acid monohydroxy alcohol ester, C12-C18 alkanoic acid polyhydroxy alkyl ester, C12-C18 alkyl acid, C12-C18 alkyl acid diol ester.Technical scheme of the present invention significantly improves continuous core-making number of times when preparing complex core, significantly improves production efficiency.
Description
Technical field
The present invention relates to binding agent, specifically, the present invention relates to a kind of amine method cold core box resinoid bond of the easy demoulding, this binder system is used for casting resin sand compound, under gaseous state amine catalyst exists, solidify to form the core mould manufacturing cast metal foundry goods, be applicable to cast various types of cast steel, cast iron and non-ferrous alloy part.
Background technology
In foundary industry, cold-box process refers to the process with gas or the at room temperature instantaneous solidification of catalytic resin sand of aerosol catalyst.By the difference of gas or aerosol catalyst, cold-box process can be divided into amine method, SO2 method, CO2 resin method and methyl formate method.
The spendable catalyst of amine method cold core box technique has triethylamine, dimethyl amine, dimethylisopropylamine etc., because triethylamine is cheap, catalyst made by usual employing triethylamine, be characterized in, setting rate is fast, coremaking efficiency is high, core sand good fluidity, the core sand up time is long, core dimensional accuracy is high and economize energy etc., meet Foundry Production high-quality, efficient, energy-conservation requirement, be applicable to the production of complicated core in enormous quantities, now be widely used in the industries such as automobile, internal combustion engine, rolling stock, aircraft, pump processed, become the main flow of various core manufacturing craft.
Along with more large batch of Foundry Production demand, and high coremaking productivity ratio, foundry goods high accuracy, high-quality, high duplication demand, Core-making unit pipelining degree is more and more higher, be integrated into a Core making center, namely with robot automation, get the sequence of operations such as core, core assembly, dip-coating to the various cores that cold-box core blower produces to continuous productive process, the production efficiency of a Core making center can reach more than 50 core groups per hour, and it is more low better that this is just desirably in frequency mould spraying releasing agent.
But current amine method cold core box resinoid bond then not too adapts to the operating type of this high pipelining.Although the binding agent of part may be had can to meet the preparation of the core of simple shape, when preparing the core of complicated shape, defect can be produced.Be embodied in: when preparing the core of complicated shape; binding agent in core is easy to bond with die surface; after carrying out the secondary coremaking of minority continuously; core (having cured) can be bonded on mould; this just needs to shut down frequently; to carry out labor cleaning, rerun again after spraying releasing agent, limit the performance of automatization level.On the other hand, high-frequency sticking to mould will certainly make more sand core surface be pulled, and causes blemish, causes the percent defective of product high, Quality Down.
Summary of the invention
Instant invention overcomes above-mentioned shortcoming, propose a kind of easy demoulding amine method cold core box binder.
The amine method cold core box binder of the easy demoulding of the present invention comprises the compound releasing agent be made up of alkene releasing agent and ester class releasing agent, described alkene releasing agent is C12-C16 monoolefine, and described ester class releasing agent is one or more in the group be made up of the single methanol ester of C12-C18 alkanoic acid monohydroxy alcohol ester, C12-C18 alkanoic acid polyhydroxy alkyl ester, C12-C18 alkyl acid, C12-C18 alkyl acid diol ester.
Use amine method cold core box binder of the present invention, significantly improve the demolding performace of core, be especially applicable to the preparation of complex-shaped core, on mould, spray the number of times of releasing agent when greatly reducing coremaking, protect environment; Improve yield rate and the production efficiency of product.
Detailed description of the invention
In the present invention, by the monoolefine of C10 to C16 and ester class releasing agent with the use of, the amine method cold core box binder obtained can significantly improve the demolding performace of resin sand.Term " monoolefine " refers to only have the straight chain of a C-C double bond or branched alkene in hydrocarbon chain, wherein preferred linear alkene.Typical example comprises the straight or branched monoolefine of 1-decene, 2-decene, 1-hendecene, 2-hendecene, 1-laurylene, 2-laurylene, 1-tridecylene, 2-tridecylene, 1-tetradecylene, 2-tetradecene, 1-ten pentaene, 2-ten pentaene, 1-hexadecylene, 2-hexadecylene and other double bond positions, and wherein branched monoolefins preferably only comprises the monoolefine of methyl, ethyl, propyl group or isopropyl.The alkene of the especially preferred C12-C14 of the present invention, most preferably linear alkene.
Be applicable to ester class releasing agent of the present invention and comprise C12-C18 alkanoic acid monohydroxy alcohol ester, C12-C18 alkanoic acid polyhydroxy alkyl ester, the single methanol ester of C12-C18 alkyl acid, the diol ester of C12-C18 alkyl acid, wherein, term " single hydroxyl alcohol " refers to only containing the C1-C6 alcohol of a hydroxyl, wherein preferred C1-C4 alcohol, such as methyl alcohol, ethanol, normal propyl alcohol, isopropyl alcohol, n-butyl alcohol, 2-butanols.Term " polyhydroxy-alcohol " refers to the alcohol containing two, three or four hydroxyls, such as ethylene glycol, glycerine (glycerine), pentaerythrite etc.Term " C12-C18 alkanoic acid polyhydroxy alkyl ester " comprises C12-C18 alkanoic acid polyhydroxy-alcohol single methanol ester and C12-C18 alkanoic acid polyhydroxy-alcohol polyol esters.Typical example comprises tristerin, glyceryl tristearate, pentaerythritol monostearate, pentaerythritol stearic acid ester 2, pentaerythrite tristearate, pentaerythritol tetrastearate, butyl stearate etc.These ester class releasing agents can be used alone, and also can be two kinds or two or more combinations.
In the present invention, the mass ratio of alkene releasing agent and ester class releasing agent preferably in the scope of 1:1 to 10:1, more preferably in the scope of 1:1 ~ 5:1, most preferably in the scope of 1:1 ~ 3:1.
In further scheme of the present invention, in releasing agent, comprise amide-type releasing agent further.Typical example comprises oleamide, stearic amide, the two oleamide of ethylene, the one of hexa-methylene two oleamide, an xyxylene bis-stearamides etc. or its combination.Such releasing agent account for releasing agent total amount 0.05 ~ 10% between.
In a kind of detailed description of the invention of the present invention, this amine method cold core box binder is made up of the raw material of following weight portion:
As the improvement of above-mentioned detailed description of the invention, this amine method cold core box binder is made up of the raw material of following weight portion:
Phenolic resins in amine method cold core box binder is benzyl ether type phenolic resins normally.In the present invention, the weight average molecular weight of benzylic ether phenolic resins is preferably 500 ~ 2000, is preferably between 600-1200.By selecting this specific benzylic ether phenolic resins, the viscosity of binding agent can be reduced, making the casting model powder being mixed with binding agent have the sand mould intensity of higher free-running property and Geng Gao.Preferably use high ortho position benzylic ether phenolic resins in the present invention, so-called high ortho position benzylic ether phenolic resins refers to the phenolic resins that neighbour/contrast is greater than 1, and major part is the phenolic resins at ortho position in other words.Use high ortho position benzylic ether phenolic resins can obtain curing rate faster.The example of the preparation of this high ortho position benzylic ether phenolic resins has disclosure in the Chinese patent CN 200710188114.3 of applicant.What adopt in embodiment hereafter is this benzylic ether phenolic resins.
May be used for PIC of the present invention and include but not limited to diphenyl methane-4,4 '-vulcabond (referred to as " MDI "), thick diphenyl methane-4,4 '-vulcabond (referred to as thick " MDI ") or polymethylene polyphenyl polyisocyanates (referred to as " PAPI ").Gaseous state amine catalyst can be triethylamine, dimethyl amine or dimethylisopropylamine, is preferably triethylamine.
In most of the cases, need in cold-box binder, introduce diluent (solvent), make this resinoid bond be suitable for mixing with molding sand.Operable solvent comprises liquid high-boiling point ester, lower alcohol and hydro carbons, such as aromatic hydrocarbons.In the present invention, high boiling ester refers to that boiling point is between 100 ~ 400 DEG C, especially between 150 ~ 400 DEG C, carboxylate particularly between 200 ~ 400 DEG C, example comprises dibutyl phthalate, dioctyl phthalate, diisobutyl phthalate, diisooctyl phthalate, adipic acid dibutyl ester, dimethyl succinate, dimethyl glutarate, dimethyl adipate; The example of lower alcohol comprises methyl alcohol, ethanol, butanols, isopropyl alcohol; It is one or more in the petroleum liquid aromatic hydrocarbons fraction of 150 ~ 290 DEG C and kerosene that the example of aromatic hydrocarbons comprises benzene,toluene,xylene and ethylbenzene and boiling range.
In the preferred embodiment of the present invention, use the mixed diluent be made up of high boiling ester and aromatic solvent, wherein introduce the effect that high boiling ester can play plasticising.The mass ratio of high boiling ester and aromatic solvent preferably in the scope of 1:1 to 5:1, more preferably in the scope of 1:1 ~ 3:1, most preferably in the scope of 1:1 ~ 2:1.
In a kind of detailed description of the invention of the present invention, this amine method cold core box binder is made up of the raw material of following weight portion:
Those skilled in the art should understand and can add other additives as siloxanes, defoamer, wetting agent etc. in aggregate or cast mixture.The specific purposes of designer are depended in the selection of special additive.The selection of these auxiliary agents and consumption are all, known by prior art, no longer describe in detail at this.
Above-mentioned each composition can be independent component, or mixes with other component, but benzylic ether phenolic resins can not mix storage with PIC.Preferably, this binding agent is made up of component I and component I I; Component I comprises the phenolic resins of all wt part, solvent and releasing agent; Component I I comprises the PIC of all wt part.Typical embodiment is, binder system is with bicomponent system packaging and use, and component I comprises the phenolic resins of all wt part and the releasing agent of moiety by weight part and hydrocarbon solvent; Component I I comprises the PIC of all wt part and the releasing agent of all the other parts and solvent.
This resin is mixed to form casting resin sand compound with casting aggregate, and described casting resin sand compound is for the manufacture of the core mould of cast metal foundry goods.
Adopt according to amine method cold core box resinoid bond of the present invention, the not easily sticking to mould when carrying out coremaking.When producing the core of complicated shape, the continuous core-making number of times of mould reaches more than 90 times, even more than 100 times, and preferably state is more than 100 times.And the continuous seepage number of times of traditional amine method cold core box resin is generally about 10 times.In addition, resinoid bond quick solidifying of the present invention, first intensity is high, facilitates manipulator clamping; Reduce the percent defective of core sand mold, improve casting quality.
Embodiment 1
The preparation of component I: be equipped with in the mixing kettle of agitator one, adds 580 kilograms, high ortho position benzylic ether phenolic resins, dibutyl phthalate 200 kilograms, Solvesso 150 hydrocarbon solvent 196 kilograms, 9 kilograms, A-187 silane, starts stirring, mix about 2 hours, make mixing of materials even.
The preparation of component I I: be equipped with in the mixing kettle of agitator one, add MDI 800 kilograms, Solvesso 150 hydrocarbon solvent 131 kilograms, butyl stearate 18 kilograms, 9 kilograms, A-187 silane, 1-tetradecylene 50 kilograms, phosphorus trichloride 6 kilograms, drives agitator, mix about 2 hours, make mixing of materials even.With container, aforesaid liquid component I and liquid component II are packed respectively, namely obtain easy demoulding amine method cold core box resin.
The intensity detection of this amine method cold core box resin is with reference to GB2684 " Foundry sand and test mixture method ".Resin sand is made into according to the ratio of 100 weight portion great Lin normal sands, 0.77 parts by weight of component I, 0.63 parts by weight of component II.First add component I and mix 1 minute with sand, then add component I I and mix 2 minutes, then being blown by MLA1 core making machine by this resin sand is pressed into tension dog-bone.Its core manufacturing craft parameter is: shooting pressure 0.4MPa, blows amine pressure 0.2MPa, and washing pressure 0.2MPa, blows 3.0 seconds amine time, wash time 5.0 seconds.
Measure 5 seconds initial strengths, 24 hours whole intensity, 24 hours high wet strength (humidity >=95%) of the test block of Eight characters tension respectively, the results are shown in Table 1.
Table 1. uses the tensile strength of the sand mold of embodiment 1 cold box resin
With the resin of the present embodiment, the core shooter suitability for industrialized production of producing with German Lan Pei company connects manifold core, working condition: addition 1.4 % of 50/100 scouring sand resin, wherein the ratio of component I and component I I is 55:45.Continuous seepage core group number of times is not less than 100 times.
Embodiment 2
The preparation of component I: be equipped with in the mixing kettle of agitator one, add 580 kilograms, high ortho position benzylic ether phenolic resins, dibutyl phthalate 200 kilograms, stearic amide 5 kilograms, Solvesso 150 hydrocarbon solvent 196 kilograms, 9 kilograms, A-187 silane, start stirring, mix about 2 hours, make mixing of materials even.
The preparation of component I I: be equipped with in the mixing kettle of agitator one, add MDI 800 kilograms, Solvesso 150 hydrocarbon solvent 131 kilograms, butyl stearate 18 kilograms, 9 kilograms, A-187 silane, 1-tetradecylene 50 kilograms, phosphorus trichloride 6 kilograms, drives agitator, mix about 2 hours, make mixing of materials even.
With container, aforesaid liquid component I and liquid component II are packed respectively, namely obtain easy demoulding amine method cold core box resin.Measure tensile strength by embodiment 1 method, the results are shown in Table 2.
Table 2. uses the tensile strength of the sand mold of embodiment 2 cold box resin
Produce by embodiment 1 method and connect manifold core, continuous seepage core group number of times is not less than 120 times.
Comparative example
The preparation of component I: be equipped with in the mixing kettle of agitator one, adds 580 kilograms, high ortho position benzylic ether phenolic resins, dibutyl phthalate 200 kilograms, Solvesso 150 hydrocarbon solvent 196 kilograms, 9 kilograms, A-187 silane, starts stirring, mix about 2 hours, make mixing of materials even.
The preparation of component I I: be equipped with in the mixing kettle of agitator one, adds MDI 800 kilograms, Solvesso150 hydrocarbon solvent 131 kilograms, butyl stearate 18 kilograms, 9 kilograms, A-187 silane, phosphorus trichloride 6 kilograms, drives agitator, mix about 2 hours, make mixing of materials even.
With container, aforesaid liquid component I and liquid component II are packed respectively, namely obtain amine method cold core box resin.Measure tensile strength by embodiment 1 method, the results are shown in Table 3.
Table 3. uses the tensile strength of the sand mold of comparative example cold box resin
Produce by embodiment 1 method and connect manifold core, after continuous seepage core mould 7 times, sticking to mould is serious, can produce after needing cleaning, release agent spraying.
Below set forth easy demoulding amine method cold core box resin of the present invention in conjunction with specific embodiments, these embodiments are just for exemplifying explanation.For a person skilled in the art, carry out multiple change and change not needing to make creative work to some details of foregoing.Within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (14)
1. the amine method cold core box binder of an easy demoulding, wherein comprise the compound releasing agent be made up of alkene releasing agent and ester class releasing agent, described alkene releasing agent is C12-C16 monoolefine, and described ester class releasing agent is one or more in the group be made up of the single methanol ester of C12-C18 alkanoic acid monohydroxy alcohol ester, C12-C18 alkanoic acid polyhydroxy alkyl ester, C12-C18 alkyl acid, C12-C18 alkyl acid diol ester.
2. amine method cold core box binder according to claim 1, wherein, described C12-C16 monoolefine is 1-position linear alkene.
3. amine method cold core box binder according to claim 1, wherein, described ester class releasing agent is one or more in tristerin, glyceryl tristearate, pentaerythritol monostearate, pentaerythritol stearic acid ester 2, pentaerythrite tristearate, pentaerythritol tetrastearate and butyl stearate.
4. amine method cold core box binder according to claim 1, wherein, the mass ratio of described alkene releasing agent and ester class releasing agent is in the scope of 1:1 to 10:1.
5. amine method cold core box binder according to claim 4, wherein, the mass ratio of described alkene releasing agent and ester class releasing agent is in the scope of 1:1 ~ 5:1.
6. amine method cold core box binder according to claim 5, wherein, the mass ratio of described alkene releasing agent and ester class releasing agent is in the scope of 1:1 ~ 3:1.
7. amine method cold core box binder according to claim 1, the raw material primarily of following weight portion forms:
8. amine method cold core box binder according to claim 7, comprises amide-type releasing agent further, accounts for 0.05 ~ 10% of releasing agent gross mass.
9. amine method cold core box binder according to claim 8, described amide-type releasing agent is one or its combination of oleamide, stearic amide, the two oleamide of ethylene, the two oleamide of hexa-methylene and an xyxylene bis-stearamides.
10. amine method cold core box binder according to claim 7, the raw material primarily of following weight portion forms:
11. amine method cold core box binders according to claim 7, wherein: described phenolic resins to be weight average molecular weight be 500 ~ 2000 high ortho position benzylic ether phenolic resins.
12. amine method cold core box binders according to claim 7, wherein, described PIC is diphenyl methane-4,4 '-vulcabond, thick diphenyl methane-4,4 '-vulcabond or polymethylene polyphenyl polyisocyanates.
13. amine method cold core box binders according to claim 10, wherein, described high boiling ester solvent be dibutyl phthalate, o-phthalic acid dibutyl ester, diisobutyl phthalate, diisooctyl phthalate, adipic acid dibutyl ester and dimethyl adipate, dimethyl succinate and dimethyl glutarate one or more.
14. amine method cold core box binders according to claim 10, wherein, described high boiling hydrocarbon solvent be one in the petroleum liquid aromatic hydrocarbons fraction of boiling range 150 ~ 290 DEG C, kerosene or its combine.
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| CN104889314A (en) * | 2015-06-08 | 2015-09-09 | 谢伟杰 | Heat-resisting releasing agent |
| CN106046283B (en) * | 2015-06-18 | 2019-04-09 | 济南圣泉集团股份有限公司 | High ortho position benzylic ether phenolic resin, preparation method and applications are in the method for cold-box binder |
| CN112548023B (en) * | 2020-12-08 | 2022-06-17 | 四川东树新材料有限公司 | Cold core box resin for high-collapsibility cast aluminum engine cylinder body and preparation method thereof |
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| JPS52152820A (en) * | 1976-06-15 | 1977-12-19 | Kuraray Co | Molding sand molding composition |
| JPS6186044A (en) * | 1984-10-03 | 1986-05-01 | Kao Corp | Release agent for casting mold |
| US4692479A (en) * | 1985-07-19 | 1987-09-08 | Ashland Oil, Inc. | Self-setting urethane adhesive paste system |
| CN100562383C (en) * | 2007-11-12 | 2009-11-25 | 济南圣泉集团股份有限公司 | A kind of high performance low smoke flame-proof amine method cold core box binder |
| CN102069141B (en) * | 2009-11-24 | 2012-10-03 | 济南圣泉集团股份有限公司 | Binder for casting core mould |
| JP5819606B2 (en) * | 2010-12-17 | 2015-11-24 | 日華化学株式会社 | Organo-modified silicone, mold release agent containing the same, and production method thereof |
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Denomination of invention: Amine method cold core box adhesive easy to demould Effective date of registration: 20211227 Granted publication date: 20151014 Pledgee: CITIC Bank Limited by Share Ltd. Ji'nan branch Pledgor: JINAN SHENGQUAN GROUP SHARE HOLDING Co.,Ltd. Registration number: Y2021980016380 |
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