Method for esterification of polyatomic alcohols with acids substituted with tertiary alkyls

FIELD: chemistry.

SUBSTANCE: method involves reaction of a polyatomic alcohol - neopentyl glycol, trimethylol propane, pentaerythritol with trialkylacetic acid in molar ratio 1:1 in the presence of an acid catalyst which is a sulphonic acid derivative having pKa between -2 and +2, carried out at temperature 180C or lower.

EFFECT: invention enables to obtain hydrolysis-resistant esters.

8 cl, 3 tbl, 15 ex

 

The present invention relates to a method for producing esters of polyols from tert-alkyl acid under reduced homopolymerization polyhydric alcohols. It is known that esters trialkylborane acids have high hydrolytic stability and enhance the hydrolytic stability present a number of complex ester. For this reason, they are highly appreciated in the coatings and/or target applications in the construction industry that require resistance to hydrolysis. This property is due to spatial difficulty due to trialkyltin group acid. Therefore, polyhydric alcohols, partially esterified trialkylborane acid, regarded as the elementary units in the synthesis of resins for coatings or applications in the construction industry.

Etherification of alcohol trialkylborane acid is difficult, and for this reason, this acid is even used as a catalyst to accelerate the esterification reaction is less complicated spatial acid with alcohol (WO 0144156).

The application of conventional esterification catalysts for the esterification of spatial hindered acid alcohol or polyhydric alcohol is known from Jour. Am. Oil. Chem. Soc., Vol 45, 5-10, January 1968, the conditions Used are, according to the authors, more stringent than for non-complicated question is rantenna acid or alcohol, and in the case of polyhydric alcohols worked with excess acid to achieve complete esterification of an alcohol functional groups.

Also known etherification strongly branched (spatial difficult) acids using non-traditional catalysts for esterification. The use of CHLOROSILANES (Bull. Chem. Soc. Jpn, 54, 1267-1268) is effective in the case of monosperma due to the formation of alkoxysilanes as the active ingredients. However, given the technology of application of this method for the partial esterification of polyols.

Of the above cited publications can be established that previous technological solutions has drawbacks, such as the use of expensive catalysts or the inability to use conditions to provide partial esterification of a polyhydric alcohol with the formation of mainly monoamino polyhydric alcohols with only small amounts of compounds of higher molecular weight, resulting from side reactions of esterification.

The way in which you can use the usual esterification catalysts to obtain mainly monoamino polyhydric alcohols, which are invaluable industry, because such a monomer is considered to be a valuable basic element for use in further synthesis resins.

p> To date, the result of extensive research and experimentation it was unexpectedly found that the choice of certain conditions in combination with a specific catalyst makes possible the predominant formation of low-viscosity complex monoether with hydroxyl functional groups of the tert-alkyl carboxylic acids and polyhydric alcohols.

Suddenly, to date, been found that the use of derivatives of sulfonic acids in mild temperature conditions is an effective combination for the production of complex monoether polyhydric alcohol without significant formation of polyethers. These polyethers are unwanted homopolymer by-products and are considered to be the product of the reaction between an alcohol functional groups; this reaction is a competing reaction, if the esterification is slow or if alcohol is used in excess relative to the acid functional groups. The present invention provides a solution to the problems, i.e. improved selective obtaining of complex monoether of polyhydric alcohols and spatial difficult carboxylic acids.

Method for the above-mentioned selective esterification reaction is carried out in the presence of the tvii acidic catalyst at a temperature below 180C.

Suitable polyhydric alcohols may be selected from ethylene glycol, propylene glycol, oligomers of glycols (n from 2 to 10), glycerol, neopentyl glycol, trimethylolpropane, pentaerythritol, and combinations thereof. The preferred polyhydric alcohol selected from ethylene glycol, neopentyl glycol, trimethylolpropane, pentaerythritol. Most preferred are neopentylglycol, trimethylolpropane.

Derived acid selected from acids of the General formula (I)

in which R1, R2independently are aliphatic alkyl radicals of from 1 to 10 carbon atoms, the total number of carbon atoms of the three radicals (CH3+R1+R2) is from 3 to 20, preferably from 3 to 13.

The acidic catalyst is selected from the derived sulfonic acids, such as methanesulfonate, econsultancy, triftormetilfullerenov, para-toluensulfonate, cellsurvival acid, and the preferred acid catalysts are methansulfonate acid or para-toluensulfonate acid. These acids are used in the range from 0.05 to 4 wt.% relative to the weight of the acid and a polyhydric alcohol. The preferred interval is from 0.10 to 2.5 wt.% from acid and a polyhydric alcohol. The most preferred catalyst is one which by methansulfonate acid.

Hydroxyl-containing ester obtained from the above-mentioned polyhydric alcohol and alanovoy acid of the formula (I)may further be used as basic units in obtaining polyester resin with improved chemical resistance.

Thus obtained resin are oligomers that can be used mainly in compositions for coatings, compositions for impregnation of fibres and as a lubricating oil.

Description of measurements and analytical methods

Measurement of strength at impact: ISO 6272-93 (E)

Measurement of the hardness of the decay time of the oscillations of the pendulum hardness according to knig): according to ISO 1522-73 (E) or DIN 53157

A brief description of the method of determining the resistance to methyl ethyl ketone (MEK)

Floor wipe with a piece of cotton wool soaked in MEK (using a pressure of about 2 kg). If the surface is wiped with a hundred times up and down with no signs of any damage, the coating is considered fully utverzhdennym. If after x double proteron MEK floor collapsed by the solid line going from top to bottom panels, the floor is considered destroyed after x double proteron IEC". Resistance to IEC was measured on hardened surfaces.

The viscosity of Newtonian systems using Brookfield viscometer: ISO 2555-89.

The invention posn what is more detail in the following examples, without limiting, however, the amount of data specific implementation options. All percentages are content by weight and all parts are parts by weight unless otherwise indicated.

EXAMPLES

Method get

Uses a 1 l round bottom glass reactor, equipped with anchor stirrer, stainless steel, thermocouple, reflux condenser Dean-stark and inlet for N2. The reactor was placed tert-alanovoy acid and polyhydric alcohol (see Tables 1 and 2 for compositions) with a molar ratio of acid/ethanol 1:1. The reaction is carried out in an atmosphere of N2with constant stirring and gradual heating. At 130C add solvent (xylene) and the catalyst. The temperature was raised to

- 150C when using trimethylhexanoic acid (V5)

- 170C when using the neo-decanoas acid (V10)

(Versatic acid 10 from Resolution Performance Products).

Temperature constant support until the acid number reaches a constant value. At this point the reaction is stopped and the reaction mixture cooled down.

Below diagram shows the structure of the products, which were identified by GC-MS analysis (with ionization detection mode POS-C1) for examples based on trimethylolpropane (TSR) as a polyhydric alcohol. In the samples simple poly is Fira were not detected.

Used catalyst:

a pair of toluensulfonate (pTSA)

methansulfonate acid (MSA 70% in water).

Mass %, are presented below in Tables for MSA, refer to the weight of the delivered solution.

pTSA was supplied in the form of solids, 97.5%, from Acros

MSA was supplied in the form of a solution (70% in water) from Atofina.

Polyhydric alcohol came:

trimethylolpropane (TSR) 97%, Aldrich

neopentylglycol (NPG) 99%, Aldrich

pentaerythritol 98%, Aldrich

Examples trimethylhexanoic acid (V5)

Table 1
Example12345678
AcidV5V5V5V5V5V5V5V5
AlcoholTSR TSRTSRTSRTSRTSRTSRTSR
The molar ratio of alcohol/acid1/11/11/11/11/11/11/11/1
CatalystpTSAMSAMSAMSAMSAMSApTSApTSA
Number cat.220,50,250,150,10,10,15
Viscosity (MPas)1971818806720450 262737420
Color (Pt/Co)173324166125736370118
Time (h)1,51,52.52,53,5565,5
Output (%)*9598,5989797959198
Ether(%)Mono3466,563,668,9no74,273,970,5
Di5933,5 35,730,7no25,626,129,5
Three700,70,4no0,300
the concentration is not carried out; * yield based on unreacted acid (consumption of catalyst: all expressed in mass of the total mass of the acid and a polyhydric alcohol)

Examples of Versatic acid 10 (V10)

Example 12. Polyester resin derived from a complex ester of a polyhydric alcohol obtained in example 6

Used a 1 l round bottom glass reactor, equipped with anchor stirrer, stainless steel, thermocouple, reflux condenser and inlet for N2. The product from example 6 (of 177.8 g) and succinic anhydride (153,6 g) were placed in the reactor in a molar ratio of 1-1 (assuming that ideally, the structure of the adduct is a complex monoether). The mixture was heated with stirring to 105C, approximately at a given temperature is the heat release and temperature increases is raised to 160C.

These reaction conditions, save to reach an acid number of. Then the reaction mixture was cooled to about 140C, before added Cardura E10 (401 g), the temperature was maintained constant within 1 hour.

Properties of polyester resin:

Color (Pt/Co): 130

Viscosity: 12 to 690 MPas

The coating composition

The cross-linking agent Cymel 301 from CYTEC.

The curing catalyst: pTSA is used in the form of a 40% solution in butanol, the concentration of 1 wt.% of the total number.

Attitude: polyester 12/Cymel=80/20.

The conditions of curing the coated Q panel: 30 min 140C.

Coating: 60 to 65 microns.

Properties of the coating: the strength of direct/reverse impact>WIMlb

Poor penetration 9 mm

Resistance to IEC>100 double proteron (MEK=methyl)

Examples 13 and 14. The polyester obtained from trimethylhexanoic acid, a polyhydric alcohol, and other acid or anhydride.

Polyesters with compositions shown in Table 3, were obtained in a glass reactor, equipped with stirrer, heater/fridge and a nozzle Dean-stark. All the ingredients were heated to 160-200C to achieve the desired acid number. To remove the reaction water by azeotropic distillation used xylene.

Ingredients Example 13Example 14
Pentaerythritol (mol)22
Methylhexahydrophthalic anhydride (mol)11
V5 (mol)34
CatalystMSAMSA
The amount of catalyst0.02 wt.%0.02 wt.%
The content HE %6,85,1
Mw892909
Mn722745
(V5): trimethylhexane acid

Example 15. Coating based on polyester 14

Estimated polyester 14 as a reaction solvent for the isocyanate cured coating. At first it was mixed with 40 wt.% with acrylic polyhydric alcohol. As the hardener used Desmodur N3600, aliphatic isocyanate of the Bayer; the catalyst was a mixture of dibutylamine of dilaurate and 1,4-diazabicyclo-2,2,2-octane; the system was diluted with butyl acetate to 100 MPaS.

This system was compared with a similar coating composition prepared from acrylic polyhydric alcohol without polyester. A mixture containing 40%, had a much less volatile organic compounds (VOC)than the material for comparison (400 against 458 g/l), but showed excellent speed of solidification and appearance. After less than 30 minutes at 60C. the system was slipnoose.

1. The method of obtaining esters, polyhydric alcohol and tert-alanovoy acid, comprising the reaction of a specified polyhydric alcohol and specified alanovoy carboxylic acid in a molar ratio of 1:1 in the presence of acidic catalyst comprising a derivative of sulfonic acid having a pKa ranging from -2 to +2, carried out at a temperature below 180C and, if necessary, in the presence of an inert organic solvent.

2. The method according to claim 1, where the acid catalyst is selected from methansulfonate, econsultancy, triftormetilfullerenov, para-toluensulfonate, cellsurvival acids.

3. The method according to claim 1, where the acid catalyst is methanesulfonate or para-toluensulfonate acid.

4. The method according to claim 1, where the acid catalyst is used in the range from 0.05 to 4 wt.%, p is edocfile from 0.10 to 2.5 wt.% relative to the weight of the acid and a polyhydric alcohol.

5. The method according to claim 1, characterized in that the derived acid selected from acids of the General formula (I),

in which R1, R2independently are aliphatic alkyl radicals of from 1 to 10 carbon atoms, the total number of carbon atoms of the three radicals (CH3+R1+R2) is from 3 to 20, preferably from 3 to 13.

6. The method according to claim 1, characterized in that the polyhydric alcohol may be selected from ethylene glycol, propylene glycol, oligomer glycol (with n from 2 to 10), glycerol, neopentyl glycol, trimethylolpropane, pentaerythritol, and combinations thereof, preferably neopentyl glycol, trimethylolpropane, pentaerythritol.

7. The resin obtained from the complex ester obtained according to any one of claims 1 to 6.

8. The coating composition containing utverzhdennuyu the resin composition according to claim 7.



 

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32 cl, 19 tbl, 67 ex, 3 dwg

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6 cl, 2 ex

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13 cl, 2 ex

FIELD: chemistry.

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7 cl, 2 ex

FIELD: chemistry.

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17 cl, 1 tbl, 5 ex

FIELD: chemistry.

SUBSTANCE: invention concerns organic compound synthesis, particularly method of obtaining 4-biphenylmetacrylate of the formula . Obtained compound is applied in production of heat and weather resistant polymer materials. Claimed method involves dissolution of 4-phenylphenol in 10 wt % aqueous solution of caustic soda, further dosage of acylating agent in the form of metacrylic acid anhydride agent in reaction mix preliminarily cooled to 0-(+5)C at such rate so as to keep the mix temperature below +10C at molar ratio of 4-phenylphenol and metacrylic acid anhydride of 1:(1.1-1.5), reaction mix maturing at room temperature with stirring, organic layer extraction, flushing by alkali solution, and drying.

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3 cl, 1 tbl, 10 ex

FIELD: chemistry.

SUBSTANCE: invention refers to advanced method of production of (meth)acrylic acid ester including (meth)acrylic acid purification by contacting raw (meth)acrylic acid containing manganese as an impurity manganese, and cation-exchange resin to remove manganese. To ensure contacting raw (meth)acrylic acid and cation-exchange resin, water is pre-added to (meth)acrylic acid. Besides, the method involves reaction of purified (meth)acrylic acid and alcohol with acid catalyst added.

EFFECT: method allows preventing effectively deactivation of the acid catalyst used in etherification reaction, equipment plugging and can ensure stable ester manufacturing.

3 cl, 5 tbl, 5 ex

FIELD: chemistry.

SUBSTANCE: invention relates to improved method of obtaining (meth)acrylic ester including stage of etherification of (meth)acrylic acid with C1-C4alcohol in presence of catalyst from highly acidic cation-exchange resin in form of immovable layer for obtaining (meth)acrylic ester; addition of polymerisation inhibitor into reactor or into distillation column for isolation; stage of isolation, at which (meth)acrylic acid that did not react is separated from reaction solution, obtained at reaction stage, where temperature in distillation column still is in the range from 60 to 100C, and pressure at the top of distillation column is in the range from 1.33 to 26.7 kPa; and recirculation stage in order to return thus obtained (meth)acrylic acid, that did not react, to reaction stage, where solid substances, contained in isolated (meth)acrylic acid that did not react and is returned to reaction stage, are isolated from it. In industry used method of obtaining (meth)acrylic esters is improved in such way as to prolong service life of used in it catalyst from highly acidic cation-exchange resin.

EFFECT: elaboration of improved method of obtaining (meth)acrylic ester.

5 cl, 2 ex, 1 dwg

FIELD: chemistry.

SUBSTANCE: present invention pertains to improvement of the method of producing (met)acrylic acid and complex (met)acrylic esters, involving the following stages: (A) reacting propane, propylene or isobutylene and/or (met)acrolein with molecular oxygen or with a gas, containing molecular oxygen through gas-phase catalytic oxidation, obtaining crude (met)acrylic acid; (B) purification of the obtained crude (met)acrylic acid, obtaining a (met)acrylic acid product; and (C) reacting raw (met)acrylic acid with alcohol, obtaining complex (met)acrylic esters, in the event that the installation used in any of the stages (B) and (C), taking place concurrently, stops. The obtained excess crude (met)acrylic acid is temporarily stored in a tank. After restoring operation of the stopped installation, the crude (met)acrylic acid, stored in the tank, is fed into the installation, used in stage (B), and/or into the installation used in stage (C). (Met)acrylic acid output of the installation used in stage (A) should be less than total consumption of (met)acrylic acid by installations used in stages (B) and (C).

EFFECT: the method allows for processing (met)acrylic acid, temporarily stored in a tank, when stage (B) or (C) stops, without considerable change in workload in stage (A).

2 ex

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to the improved method for preparing dimethyl-1,5-naphthalene dicarboxylate that is used in preparing polymers based on thereof and articles made of these polymers. The economic and effective method involves the following stages: (1) dehydrogenation of 1,5-dimethyltetraline to yield 1,5-dimethylnaphthalene; (2) oxidation of 1,5-dimethylnaphthalene prepared at dehydrogenation stage to yield 1,5-naphthalene dicarboxylic acid being without accompanying isomerization stage, and (3) esterification of 1,5-naphthalene dicarboxylic acid prepared at oxidation stage in the presence of methanol to yield the final dimethyl-1,5-naphthalene dicarboxylate.

EFFECT: improved preparing method.

9 cl, 3 dwg, 5 ex

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