CN102249931B

CN102249931B - Method for synthesizing 3,3'-dimethyl-4,4'-diamidodiphenylmethane

Info

Publication number: CN102249931B
Application number: CN 201110127467
Authority: CN
Inventors: 王良成; 张强; 武祥; 王良璧; 常立民
Original assignee: Lanzhou Jiaotong University
Current assignee: Lanzhou Jiaotong University
Priority date: 2011-05-17
Filing date: 2011-05-17
Publication date: 2013-10-23
Anticipated expiration: 2031-05-17
Also published as: CN102249931A

Abstract

The invention provides a novel environmentally-friendly method for synthesizing 3,3'-dimethyl-4,4'-diamidodiphenylmethane (2MMDA1). The method comprises the following steps: by taking o-toluidine, hydrochloric acid and formaldehyde as raw materials, carrying out condensation reaction on the raw materials in the presence of no catalyst so as to obtain the hydrochloride of 2MMDA1; and then filtering, washing, drying and recrystallizing so as to obtain a target product, wherein sewage generated in the process is regulated by using diluted phosphoric acid so that the pH reaches about 7.0, the sewage is subjected to standing and precipitation, and supernate is taken for later use. The yield of 2MMDA1 is 75-85%, and the purity of 2MMDA1 is 95%. Relative to reported processes, the method provided by the invention has the advantages that: (1) the catalyst is not introduced in the reaction process, and sewage generated in the process and secondary pollution of solvent used for recrystallization can be avoided; and (2) ammonia water, potassium hydroxide and phosphoric acid are used as neutralization reagents, the finally generated sewage is rich in NH<4+>, k<+> and PO4<3-> ions which are necessary for plant growth; and the sewage after dilution can be directly used for irrigating a tree farm and a grass land, thereby achieving the harmless utilization of the sewage.

Description

A kind of method of synthetic 3,3'-dimethyl-4,4 '-diaminodiphenylmethane

Technical field

The present invention relates to the synthesis technical field of organic monomer, particularly a kind of method of synthetic 3,3'-dimethyl-4,4 '-diaminodiphenylmethane.

Background technology

3,3'-dimethyl-4,4'-diaminodiphenylmethane (being called for short 2MMDA1) is white or canescence thallus or needles (mainly being the solvent of using when depending on that what is refining), main as Resins, epoxy, the mucous membrane agent of urethane resin, solidifying agent, be characterized in thermotolerance, drug resistance, good electric performance.2MMDA1 and MALEIC ANHYDRIDE are comprehensive, namely get polyimide resin with the diamines pre-polymerization again, moreover 2MMDA1 and pyromellitic acid dianhydride condensation namely get polyimide resin.Goods with above-mentioned materials processing have the heat-resisting of excellence, and insulating property reach the stability to solvent, thus multiplex in high temperature varnish, the film of electric capacity, printed chassis and aviation part etc.In addition, 2MMDA1 also is commonly used for epoxy resin cross-linking agent, the insulation compound of circuit, the lubricant of glass fibre, and the solidifying agent of Resins, epoxy.As seen 3,3'-dimethyl-4,4 '-diaminodiphenylmethane of many uses.Although consumption is little, the at present domestic import of still needing, and price comparison is high.

According to domestic and foreign literature, the synthetic method of 3,3'-dimethyl-4,4 '-diaminodiphenylmethane has following four kinds:

(1) reaction in HCI solution of Ortho Toluidine and formaldehyde makes

The method is progressively to drip HCI in Ortho Toluidine at 40-60 ℃, makes both uniform contact under constantly stirring, and makes whole aniline all generate anilinechloride.Then add formaldehyde (aqueous solution of formaldehyde contains formaldehyde 37%) and carry out condensation with anilinechloride, improve temperature to 85-90 ℃ again, make its transposition, this temperature was namely finished translocation reaction in 3 hours.Then with the mixing solutions cool to room temperature, with the neutralization of NaOH solution.When the pH value near 7 the time, precipitate particle shape crude product 2MMDA1, elimination solution, washing, drying.The thick product 2MMDA1 of gained is obtained purity 99% above white needles body, fusing point l58 ℃ with ethyl alcohol recrystallization.

(2) Ortho Toluidine and formaldehyde are at H ₂SO ₄Reaction in the solution makes

Under l50-350 ℃ temperature, use strong acid H ₂SO ₄And there have NaCl to exist to be lower to Ortho Toluidine and formaldehyde condensation (under the pressure) cooling, uses Na ₂CO ₃In the place, namely obtain 2MMDA1.

(3) condensation on wilkinite of Ortho Toluidine and formaldehyde makes

Ortho Toluidine and formaldehyde are on excessive wilkinite, and temperature 130-150 ℃ adds thermal condensation, and namely obtains 2MMDA1 through molecular transposition.

(4) condensation reaction under the ion-exchange resin catalyst effect of Ortho Toluidine and formaldehyde makes

Many cyclisation platform thing that o-toluidine and formaldehyde condensation generate reacts by ion exchange resin, and this ion exchange resin contains perfluoroalkyl and sulfate.The mixture of o-toluidine and formaldehyde is 50 ℃ of lower heating 2 hours, improves afterwards temperature to 85 ℃, under the effect of ion exchange resin, can obtain 2MMDA1.

It is best that Ortho Toluidine and the reaction of formaldehyde in HCI solution make the method for 2MMDA1 and feasibility other three kinds of methods of comparing.Need product Crystallization Separation drying but also exist from being condensed to transposition, operation steps is complicated, easily causes side reaction, and because intermediate product contacts easily generation heat-tinting for a long time with air.Obtain the product of higher degree such as needs.Recrystallization repeatedly then, this will reduce yield, if obtain the product of high yield, then product purity is undesirable again.

Summary of the invention

Technical problem to be solved by this invention provides a kind of method of synthetic 3,3'-dimethyl-4,4 '-diaminodiphenylmethane of more environmental protection.

Another object of the present invention is the utilization to the sewage that produces in synthetic 3, the 3'-dimethyl-4,4 '-diaminodiphenylmethane process.

Technical problem of the present invention adopts following technical proposals to solve:

A kind of method of synthetic 3,3'-dimethyl-4,4 '-diaminodiphenylmethane, take Ortho Toluidine and formaldehyde as raw material, react in HCI solution by following processing step and to make 2MMDA1:

A. in the four-hole boiling flask that agitator and thermometer are housed, add Ortho Toluidine, logical nitrogen protection;

B. the hydrochloric acid with 36.5 % is diluted to 6.5-7.3%, presses the molar ratio of Ortho Toluidine and hydrochloric acid consumption 1:1-1.5, pours in the dropping funnel, drips time for adding 0.5-1.5 h under 15-30 ℃ of temperature;

C. with the formaldehyde of concentration 37%, be the molar ratio of 2:0.1-1.3 by Ortho Toluidine and formaldehyde consumption, in 0.5-1.5h, dropwise, synthermal lower reaction 1-1.5 h; In 1-1.5 h, progressively be warmed up to 55-60 ℃ again, reaction 1-1.5h; 0.5h interiorly progressively be warmed up to 72-74 ℃, reaction 2-3h;

D. reaction finishes, and when treating that nature cools to 35 ℃, dripping excessive ammonia to pH is 7-8, and changing hydro-oxidation potassium, to transfer pH be 9-9.5, filter and obtain buff powder, washing, dry, use ethyl alcohol recrystallization, obtain white crystal.

Filter and wash the sewage that produces in the described technological process and transfer pH to 7.0-7.1 with 30% phosphoric acid, staticly settle, add the fresh water dilute sewage, make the total concn of ammonium ion in the sewage, phosphate anion and potassium ion at 1%-2%, collect supernatant liquor for subsequent use.

The yield 75-85 % of the synthetic 2MMDA1 of the inventive method, purity〉95 %.Reaction equation is as follows:

Figure 2011101274679100002DEST_PATH_IMAGE001

(2) performance measurement of 2MMDA1

(1) fusing point of 2MMDA1

Adopt MELTING POINT TESTER, regulating temperature rise rate is 1 ℃/min, and the fusing point that records 2MMDA1 is 157-158 ℃, conforms to literature value, and melting range is 2 ℃, shows that its purity is higher.

(2) the hydrogen nuclear magnetic resonance spectrum analysis of 2MMDA1

The hydrogen position	Corresponding hydrogen number	Peak shape	Chemical shift
				a (C-NH)	4	s	3.71
b (CH ₂)	2	s	3.45
				C (phenyl ring hydrogen)	6	s	6.72
d（CH ₃）	6	s	2.16

(3) utilization that produces sewage in synthetic 3, the 3'-dimethyl-4,4 '-diaminodiphenylmethane process

Learn according to laboratory study, one ton of 2MMDA1 of every production will produce the production waste of 4-5 ton.Because the difference of production technique, contained mineral substance is also different in the sewage.At present, the sewage of sodium-chlor is rich in the technological process generation that both at home and abroad reaction in HCI solution makes 2MMDA1 with Ortho Toluidine and formaldehyde, the content of sodium-chlor is about 5-8% in this sewage, and is more taller than sodium-chlor in the seawater 3%, and the processing cost of this sewage will be very high.Contain a large amount of ammonium chloride in the sewage that the designed production technique of the present invention produces, ammonium phosphate and a small amount of Repone K, these ions account for the 3-4% of sewage gross weight, ammonium ion wherein, phosphate anion, potassium ion is the essential nutritive element of plant-growth, if this sewage is added the fresh water dilution, the total concn of above-mentioned three kinds of ions is controlled at about 1-2%, this sewage had both solved facilitate afforestation on barren hills and had cultivated the needed water in grassland, solve again simultaneously facilitate afforestation on barren hills and cultivated the grassland to the demand of fertilizer, the more important thing is the outlet that has found a green for processing and the recycling of industrial sewage.

The present invention carries out condensation and transposition two steps reaction in same reactor continuously, will not separate by intermediate product.Not only simplified technique, and the purity of product and yield reach respectively more than 95% and 75-85 %.

The method of the synthetic 2MMDA1 of the present invention is simple, and processing condition are gentle, and reaction is carried out in the aqueous solution, and cost is low, and effectively suppresses the generation of other side reaction, and the sewage that produces in reaction process simultaneously can solve forest and the grassland is irrigated and the needs of fertilizer.

Embodiment

Embodiment 1

A kind of method of synthetic 3,3'-dimethyl-4,4 '-diaminodiphenylmethane comprises following processing step:

A. in the four-hole boiling flask that agitator and thermometer are housed, add the 10.7g Ortho Toluidine, logical nitrogen protection;

B. with the 12 g hydrochloric acid of 36.5 % with distilled water diluting to 50ml, hydrochloric acid is 7.3% after the dilution, pours in the dropping funnel, drips time for adding 0.5 h under 15 ℃ of temperature;

C. the formaldehyde with 4.06g concentration 37% dropwises in 0.5h, synthermal lower reaction 1 h; In 1.5 h, progressively be warmed up to 55 ℃ again, reaction 1h; 0.5h interiorly progressively be warmed up to 72 ℃, reaction 2h;

D. reaction finishes, and when treating that nature cools to 35 ℃, dripping excessive ammonia to pH is 7, and changing hydro-oxidation potassium, to transfer pH be 9, filter and obtain buff powder, washing, dry, use ethyl alcohol recrystallization, obtain white crystal.Yield is 75%, and purity is 95%.

Filter and wash the sewage that produces in the above-mentioned technological process and transfer pH to 7.0 with 30% phosphoric acid, staticly settle, add the fresh water dilute sewage, make the total concn of ammonium ion in the sewage, phosphate anion and potassium ion 1%, collect the irrigation that supernatant liquor is used for facilitate afforestation on barren hills and cultivates the grassland.

Embodiment 2

B. with the 15 g hydrochloric acid of 36.5 % with distilled water diluting to 70ml, hydrochloric acid is 6.5% after the dilution,, pour in the dropping funnel, under 30 ℃ of temperature, drip time for adding 1.5 h;

C. the formaldehyde with 5.27g concentration 37% dropwises in 1.5h, synthermal lower reaction 1.5 h; In 1h, progressively be warmed up to 60 ℃ again, reaction 1.5h; 0.5h interiorly progressively be warmed up to 74 ℃, reaction 3h;

D. reaction finishes, and when treating that nature cools to 35 ℃, dripping excessive ammonia to pH is 8, and changing hydro-oxidation potassium, to transfer pH be 9.5, filter and obtain buff powder, washing, dry, use ethyl alcohol recrystallization, obtain white crystal.Yield is 85%, and purity is 97%.

Filter and wash the sewage that produces in the above-mentioned technological process and transfer pH to 7.1 with 30% phosphoric acid, staticly settle, add the fresh water dilute sewage, make the total concn of ammonium ion in the sewage, phosphate anion and potassium ion 2%, collect the irrigation that supernatant liquor is used for facilitate afforestation on barren hills and cultivates the grassland.

Claims

1. the method for synthetic 3, a 3'-dimethyl-4,4 '-diaminodiphenylmethane, take Ortho Toluidine and formaldehyde as raw material, react in HCI solution by following processing step and to make 2MMDA1:

C. with the formaldehyde of concentration 37%, press Ortho Toluidine and formaldehyde than being the molar ratio of 2:0.1-1.3, in 0.5-1.5h, dropwise synthermal lower reaction 1-1.5 h; In 1-1.5 h, progressively be warmed up to 55-60 ℃ again, reaction 1-1.5h; 0.5h interiorly progressively be warmed up to 72-74 ℃, reaction 2-3h;

2. as claimed in claim 1 a kind of synthetic 3,3'-dimethyl-4, the method of 4'-diaminodiphenylmethane, it is characterized in that: filter and wash the sewage that produces in the described technological process and transfer pH to 7.0-7.1 with 30% phosphoric acid, staticly settle, add the fresh water dilute sewage, make the total concn of ammonium ion in the sewage, phosphate anion and potassium ion at 1%-2%, collect supernatant liquor for subsequent use.