Liquid 1,3-dioxolane copolymer

Abstract

The present invention relates to 1,3-dioxolane copolymers of general formula I and methods for their preparation. H-[O-CH2-O-CH2-CH2-] x1 [O-CH2-CH2O-CH2-] x2 [O-CH2-O-CHR 1 -CHR 2 -] y1 [O-CHR 1 -CHR 2 O-CH2-] y2 OH (I) (In the formula, x1+x2 is a value between 10 and 2000, R 1 and R 2 is hydrogen or C1-C 18 is an alkyl group, Unit [O-CH2-O-CHR 1 -CHR 2 -] y1 and unit [O-CHR 1 -CHR 2 O-CH2-] y2 In each case, the group R 1 or group R 2 At least one of C1 to C 18 is an alkyl group, However, y1+y2 is 3×(x1+x2+y1+y2) / 100 ~ 50×(x1+x2+y1+y2) / 100.)

Description

[Technical field]

[0001] The present invention relates to a 1,3-dioxolane copolymer of 1,3-dioxolane and an alkyl-substituted 1,3-dioxolane, and a method for producing the same. [Background technology]

[0002] It is clear that increasing CO2 emissions contribute significantly to climate change, and it has been proven, not just since the signing of the Paris Climate Agreement, that reducing CO2 emissions is a key factor in stopping the increase in global average temperatures. Plastic production also releases a significant amount of CO2 into the atmosphere, with EIT Climate-KIC forecasting that by 2050, 15-20% of global CO2 emissions will come from plastic production alone. One way to reverse this trend is to utilise CO2 in plastic production, incorporating it into the value chain as a starting material rather than as a waste product. In this context, polyacetals are an attractive class of plastics, which can be produced, inter alia, via cyclic acetal intermediates by catalytic fixation of CO2 with environmentally friendly hydrogen. However, conventional polyacetals, also called polyoxymethylenes (POM), such as those available by polymerization of formaldehyde or trioxane (POM-H) or by ring-opening polymerization of 1,3-dioxolane (POM-C), are solid at room temperature due to their crystalline fraction and associated melting point, which hinders further processing and functionalization in some applications. Summary of the Invention [Problem to be solved by the invention]

[0003] It was therefore an object of the present invention to provide a polyacetal which is liquid over a wide temperature range and which can be produced from a cyclic acetal. The intention of introducing controlled imperfections in the form of alkyl groups pendant from the polymer backbone is to eliminate, not merely reduce, the crystallinity of the polyacetal, and such amorphous nature can be detected by differential scanning calorimetry, given that there is only a glass transition temperature and no melting point.

[0004] US Pat. No. 7,030,207 BB describes polyacetals formed from trioxane and 1,3-dioxolane, which can lower the crystallization temperature of the polyacetal, but the polymer crystallizes at a lower temperature than specified.

[0005] The publication "Thermal Stability and Dynamic Mechanical Properties of Acetal Copolymers", Angew. Makromol. Chem., 1999, Vol. 265, pp. 55-61, describes the copolymerization of trioxane with alkylated 1,3-dioxolanes, but no liquid products are obtained.

[0006] Masahiko Okada et al., "Polymerizability of Methyl-Substituted 1,3-Dioxolanes," Makromolekulare Chemie, Vol. 176, pp. 859-872 (1975), describes the polymerization of 4-methyl-1,3-dioxolane by itself to form a viscous polymer in which the monomer and polymer exist in equilibrium. This polymerization requires very long reaction times of several days at low temperatures.

[0007] EP 3020741 A describes the possibility of preparing copolymers from 1,3-dioxolane and other monomers, but does not describe the properties of these copolymers. [Means for solving the problem]

[0008] The present invention provides 1,3-dioxolane copolymers of general formula I: H-[O-CH2-O-CH2-CH2-] x1 [O-CH2-CH2O-CH2-] x2 [O-CH2-O-CHR1 -CHR 2 -] y1 [O-CHR 1 -CHR 2 O-CH2-] y2 OH (I) (In the formula, x1+x2 is a value between 10 and 2000, R 1 and R 2 is hydrogen or C1-C 18 is an alkyl group, Unit [O-CH2-O-CHR 1 -CHR 2 -] y1 and unit [O-CHR 1 -CHR 2 O-CH2-] y2 In each case, the group R 1 or group R 2 At least one of C1 to C 18 is an alkyl group, However, y1+y2 is 3×(x1+x2+y1+y2) / 100 ~ 50×(x1+x2+y1+y2) / 100.) DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Copolymers are formed from 1,3-dioxolanes and 1,3-dioxolanes substituted at the 4- and / or 5-positions, which are liquid over a wide temperature range and are therefore very suitable for further processing. The copolymer preferably has a glass transition between -50°C and -70°C, and particularly preferably has no melting point. The copolymer begins to decompose above 110°C, especially above 100°C.

[0010] 1,3-dioxolane copolymers consist of the units [O-CH2-O-CH2-CH2-] x1 , unit [O-CH2-CH2O-CH2-] x2 , the unit [O-CH2-O-CHR 1 -CHR 2 -] y1 , unit [O-CHR1 -CHR 2 O-CH2-] y2 , either randomly or in blocks.

[0011] x1+x2 is preferably a value of 20-1000, more preferably a value of 30-500, and particularly preferably a value of 50-300.

[0012] Alkyl group R 1 and R 2 Examples of R include linear and branched alkyl groups such as methyl, ethyl, i-octyl and n-octyl groups, and cycloalkyl groups such as cyclohexyl. 1 and R 2 is preferably hydrogen or a C1 to C6 alkyl group, and particularly preferably hydrogen or a methyl group, an ethyl group, an n-propyl group or an i-propyl group.

[0013] Unit [O-CH2-O-CHR 1 -CHR 2 -] y1 and unit [O-CHR 1 -CHR 2 O-CH2-] y2 In each case, the group R 1 or group R 2 Only one of the following is C1~C 18 It is preferably an alkyl group.

[0014] It is preferable that y1+y2 is a value of 5×(x1+x2+y1+y2) / 100 to 40×(x1+x2+y1+y2) / 100, particularly preferably a value of 10×(x1+x2+y1+y2) / 100 to 30×(x1+x2+y1+y2) / 100, and in particular a value of 14×(x1+x2+y1+y2) / 100 to 25×(x1+x2+y1+y2) / 100.

[0015] The molecular weight Mw of the 1,3-dioxolane copolymer is preferably between 750 and 300,000, particularly preferably between 1,500 and 125,000, extremely preferably between 2,200 and 63,000, and particularly preferably between 4,000 and 25,000.

[0016] The dynamic viscosity of the 1,3-dioxolane copolymer at 25° C. is preferably between 50 mPas and 500 Pas, particularly preferably between 500 mPas and 200 Pas, and in particular between 1 Pas and 100 Pas.

[0017] The 1,3-dioxolane copolymers of formula I above can be prepared by simple methods and short reaction times.

[0018] The present invention also provides a method for preparing a 1,3-dioxolane copolymer of general formula I above, comprising the step of copolymerizing 1,3-dioxolane with an alkyl-substituted 1,3-dioxolane of general formula II in the presence of a Lewis acid or a Bronsted acid. H-[O-CH2-O-CH2-CH2-] x1 [O-CH2-CH2O-CH2-] x2 [O-CH2-O-CHR 1 -CHR 2 -] y1 [O-CHR 1 -CHR 2 O-CH2-] y2 OH (I) (In the formula, x1+x2 is a value between 10 and 2000, R 1 and R 2 is hydrogen or C1-C 18 is an alkyl group, Unit [O-CH2-O-CHR 1 -CHR 2 -] y1 and unit [O-CHR 1 -CHR 2 O-CH2-] y2 In each case, the group R1 or group R 2 At least one of C1 to C 18 is an alkyl group, However, y1+y2 is 3×(x1+x2+y1+y2) / 100 ~ 50×(x1+x2+y1+y2) / 100.) [ka]

[0019] In the general formula II, alkyl groups R 1 and R 2 There is. The method is a cationic induced catalyzed ring-opening polymerization of dioxolane monomers. The catalyst is a Lewis or Bronsted acid.

[0020] In the process, it is preferred to use at least 10 mol %, particularly preferred to use at least 20 mol %, in particular at least 30 mol %, of the alkyl-substituted 1,3-dioxolane of general formula II, based on the total amount of 1,3-dioxolane and alkyl-substituted 1,3-dioxolanes of general formula II.

[0021] Because the alkyl substituted 1,3-dioxolanes of general formula II are less reactive than 1,3-dioxolanes, the process requires the use of more than is arithmetically necessary to achieve a given ratio of y1+y2.

[0022] Examples of acids include Lewis acids such as BF3, AlCl3, TiCl3, SnCl4, SO3, PCl5, POCl3, FeCl3, and their hydrates, as well as ZnCl2; boric acid, tetrafluoroboric acid, nitric acid, nitrous acid, phosphoric acid, phosphorous acid, hypophosphorous acid, sulfuric acid, sulfurous acid, peroxysulfuric acid, hydrochloric acid, hydrofluoric acid, hydroiodic acid, hydrobromic acid, perchloric acid, hexafluorophosphoric acid, aluminum chloride, zinc chloride, benzenesulfonic acid, and p-toluenesulfonic acid. , methanesulfonic acid, trifluoromethanesulfonic acid, carboxylic acids (such as chloroacetic acid, trichloroacetic acid, acetic acid, acrylic acid, benzoic acid, trifluoroacetic acid, citric acid, crotonic acid, formic acid, fumaric acid, maleic acid, malonic acid, gallic acid, itaconic acid, lactic acid, tartaric acid, oxalic acid, phthalic acid, and succinic acid), acidic ion exchangers, acidic zeolites, acid-activated bleaching earth, and acid-activated carbon black.

[0023] Particularly preferred are boron trifluoride etherate and trifluoromethanesulfonic acid.

[0024] In the present method, an initiator can be used, which is preferably a monohydric alcohol or a dihydric alcohol, and particularly preferably ethylene glycol.

[0025] The process may be carried out in the presence or absence of an aprotic solvent. When an aprotic solvent is used, a solvent or mixture of solvents having a boiling point or boiling range of up to 120° C. at 0.1 MPa is preferred. Such solvents include ethers such as dioxane, tetrahydrofuran, diethyl ether, methyl tert-butyl ether, diisopropyl ether, diethylene glycol dimethyl ether, and the like; chlorinated hydrocarbons such as dichloromethane, trichloromethane, tetrachloromethane, 1,2-dichloroethane, trichloroethylene, and the like; hydrocarbons such as pentane, n-hexane, hexane isomer mixtures, heptane, octane, benzine, petroleum ether, benzene, toluene, xylene, and the like; siloxanes, particularly dimethylsiloxane units with trimethylsilyl groups as terminal groups, are preferred. Examples of the dimethylsiloxane include linear dimethylpolysiloxanes having 0 to 6 dimethylsiloxane units, or cyclic dimethylpolysiloxanes having preferably 4 to 7 dimethylsiloxane units, such as hexamethyldisiloxane, octamethyltrisiloxane, octamethylcyclotetrasiloxane, and decamethylcyclopentasiloxane; ketones such as acetone, methyl ethyl ketone, diisopropyl ketone, and methyl isobutyl ketone (MIBK); esters such as ethyl acetate, butyl acetate, propyl propionate, ethyl butyrate, and ethyl isobutyrate; and carbon disulfide and nitrobenzene, or a mixture of these solvents.

[0026] The term "solvent" does not imply that all reactants must be dissolved in the solvent. Reactions may be carried out in a suspension or emulsion of one or more reactants. Reactions may be carried out in a solvent mixture with a miscibility gap, where at least one reactant is soluble in each mixed phase.

[0027] It is particularly preferred to use a solution of trifluoromethanesulfonic acid and initiator together with methylene chloride as the preferred solvent. The amount of catalyst and initiator used determines the achievable molecular weight of the 1,3-dioxolane copolymer of general formula I.

[0028] The process is preferably carried out at a temperature between 10° C. and 60° C., particularly preferably between 15° C. and 40° C., in particular between 21° C. and 30° C. A reaction temperature of 23° C. is highly preferred.

[0029] The reaction is preferably driven to completion by deactivating the catalyst with a suitable base, washing with a hydrocarbon such as heptane, and drying under reduced pressure. Suitable bases include, preferably, pyridine, triethylamine or aqueous sodium hydroxide.

[0030] In the following examples, unless otherwise specified, all amounts and percentages are by weight, all pressures are 0.10 MPa (absolute pressure), and all temperatures are 20°C. EXAMPLES

[0031] Overall Analysis of the Invention:

[0032] NMR spectroscopy to determine the proportion of alkylethylene oxide bridges y1+y2: Bruker Avance 500 or Ascend 500 (500MHz, 1 The measurements are performed in CDCl3 solution using a 1H spectrum. All measurements are referenced to TMS as an external standard. The relative proportions of monomer units in the polymer are determined by integrating each group of signals.

[0033] SEC (size exclusion chromatography) for determining the number average molecular weight Mn and the weight average molecular weight Mw and the polydispersity: Polystyrene standards are run in THF at 35° C., a flow rate of 0.3 mL / min, detection with a RID (refractive index detector) with an injection volume of 20 μL on an Agilent PLgel MiniMIX-C guard column.

[0034] Rheometer for determining dynamic viscosity: The measurements are made with an Anton Paar MCR 320 rotational viscometer at 25° C. The viscosity is plotted against the shear stress and a graphical evaluation is made.

[0035] DSC (Differential Scanning Calorimetry / Differential Thermal Analysis) for determining melting points and glass transition temperatures: Using a Mettler Toledo DSC-1 instrument, the temperature rise or fall rate is set to 10 K / min and two runs are performed in the temperature range from -150°C to 150°C. The second run is used to determine the melting point and glass transition temperature.

[0036] TGA analysis to determine the onset of decomposition: The onset of decomposition is determined using a Mettler Toledo TGA-2 instrument by heating the sample at a rate of 10 K / min in an oxygen atmosphere.

[0037] Example 1, not according to the invention: 8.0 mL (114 mmol) of 1,3-dioxolane (DXL) is placed in a flask and 14 μL of boron trifluoride etherate is added while stirring. An increase in viscosity is observed and after 10 minutes the reaction mixture becomes solid. 5 mL of a 5% by weight solution of sodium carbonate is added. The mixture is dissolved in dichloromethane and the product is precipitated in heptane and filtered. The white solid is dried under reduced pressure.

[0038] Experimental Example 2: 3.6 mL (50 mmol) of 1,3-dioxolane (DXL) and 5.1 g (50 mmol) of 4-ethyl-1,3-dioxolane (EDX) are placed in a flask and 14 μL of boron trifluoride etherate are added while stirring. An increase in viscosity is observed. After 4 hours, 5 mL of a 5% by weight sodium carbonate solution is added and the product is washed with heptane. The viscous residue is dried under reduced pressure.

[0039] Experimental Example 3: 5.2 mL (75 mmol) of 1,3-dioxolane (DXL) and 2.55 g (25 mmol) of 4-ethyl-1,3-dioxolane (EDX) are placed in a flask and 14 μL of boron trifluoride etherate are added while stirring. An increase in viscosity is observed. After 2 hours the reaction mixture can no longer be stirred. 5 mL of a 5% by weight solution of sodium carbonate and dichloromethane are added and the product is precipitated in heptane. The viscous white residue is dried under reduced pressure.

[0040] Experimental Example 4: 5.8 mL (83 mmol) of 1,3-dioxolane (DXL) and 1.74 g (17 mmol) of 4-ethyl-1,3-dioxolane (EDX) are placed in a flask and 14 μL of boron trifluoride etherate are added while stirring. The reaction is highly exothermic and an increase in viscosity is observed. After 5 min, the reaction mixture can no longer be stirred. 5 mL of a 5% by weight solution of sodium carbonate and 5 mL of dichloromethane are added and the product is precipitated in heptane. The white solid is dried under reduced pressure.

[0041] Experimental Example 5: 5.1 g (50 mmol) of 4-ethyl-1,3-dioxolane (EDX) and 14 μL of boron trifluoride etherate are placed in a flask. Within 15 min, 3.6 mL (50 mmol) of 1,3-dioxolane (DXL) are added dropwise with stirring. After 2 h, the reaction mixture is quenched by adding 5 mL of a 5% by weight sodium carbonate solution. After the addition of dichloromethane, the product is washed with heptane and dried under reduced pressure. A viscous oil is obtained.

[0042] Experimental Example 6: 2.55 g (25 mmol) of 4-ethyl-1,3-dioxolane (EDX) and 14 μL of boron trifluoride etherate are placed in a flask. Within 30 min, 4.2 mL (60 mmol) of 1,3-dioxolane (DXL) are added dropwise with stirring. After 2 h, 5 mL of a 5% by weight solution of sodium carbonate is added to quench the reaction mixture. After the addition of dichloromethane, heptane is added dropwise to the product, the heptane phase is removed and the residue is dried under reduced pressure. A viscous oil is obtained.

[0043] For Experimental Examples 7 to 10: Preparation of catalyst solution: 10 mL of dry dichloromethane, 1000 μL of ethylene glycol, and 76 μL of trifluoromethanesulfonic acid are mixed and stirred at room temperature for 1 hour.

[0044] Experiment 7: 4.5 mL of catalyst solution and 4.5 mL of dry dichloromethane are placed in a flask and the temperature is adjusted to 23° C. Then 67.5 g (640 mmol) of 4-ethyl-1,3-dioxolane (EDX) and 45 mL (640 mmol) of 1,3-dioxolane (DXL) are added and stirred. The reaction turns a pale red color. After 4.5 hours, pyridine is added until the mixture is colorless. The product is washed with heptane and then dried under reduced pressure.

[0045] Experimental Example 8: 9.0 mL of the catalyst solution is placed in the flask and the temperature is adjusted to 23° C. Then, 67.5 g (640 mmol) of 4-ethyl-1,3-dioxolane (EDX) and 45 mL (640 mmol) of 1,3-dioxolane (DXL) are added and the reaction mixture is stirred for 60 minutes at 21° C. The reaction mixture turns a pale red color. After 5.5 hours, pyridine is added until the mixture is colorless. The product is washed with heptane and then dried under reduced pressure.

[0046] Example 9: 0.25 mL of catalyst solution and 0.25 mL of dichloromethane are placed in a flask. Then, 3.75 g (35 mmol) of 4-ethyl-1,3-dioxolane (EDX) and 2.5 mL (35 mmol) of 1,3-dioxolane (DXL) are added and the mixture is stirred at 23° C. for 3 hours. 10 mL of dichloromethane is added, followed by dropwise addition of 10% sodium hydroxide solution until the pH is 7. The product is washed twice with 20 mL of water and dried under reduced pressure.

[0047] Example 10: 0.25 mL of catalyst solution and 0.25 mL of dichloromethane are placed in a flask. Then 800 mg (8 mmol) of 4-ethyl-1,3-dioxolane (EDX) and 4.7 mL (67 mmol) of 1,3-dioxolane (DXL) are added and the mixture is stirred at 23° C. After 4 hours, 1 mL of pyridine and 5 mL of dichloromethane are added. After the addition of heptane, the supernatant is decanted and the product is dried under reduced pressure. A white solid is obtained.

[0048] [Table 1]

Claims

1. A 1,3-dioxolane copolymer of general formula I. H-[O-CH ２ -O-CH ２ -CH ２ -] ｘ１ [O-CH ２ -CH ２ P.S. ２ -] ｘ２ [O-CH ２ -O-CHR １ -CHR ２ -] ｙ１ [O-CHR １ -CHR ２ O-CH ２ -] ｙ２ OH (I) (In the formula, x1+x2 is a value between 10 and 2000, R １ and R ２ is hydrogen or C １ ~C １８ is an alkyl group, Unit [O-CH ２ -O-CHR １ -CHR ２ -] ｙ１ and the unit [O-CHR １ -CHR ２ O-CH ２ -] ｙ２ In each of the above, the group R １ or group R ２ At least one of １ ~C １８ is an alkyl group, However, y1+y2 is a value between 3×(x1+x2+y1+y2) / 100 and 50×(x1+x2+y1+y2) / 100.)

2. group R １ and group R ２ 2. The 1,3-dioxolane copolymer of claim 1, wherein is selected from hydrogen, a methyl group, an ethyl group, an n-propyl group, or an isopropyl group.

3. Unit [O-CH ２ -O-CHR １ -CHR ２ -] ｙ１ and the unit [O-CHR １ -CHR ２ O-CH ２ -] ｙ２ In each of the above, the group R １ or group R ２ Only one of them is C １ ~C １８ 3. The 1,3-dioxolane copolymer according to claim 1, wherein the alkyl group is an alkyl group.

4. 4. The 1,3-dioxolane copolymer according to any one of claims 1 to 3, having a molecular weight Mw of 750 to 300,000 as measured using polystyrene as a standard in THF at 35°C, a flow rate of 0.3 mL / min, detection with a RID (refractive index detector) on an Agilent PLgel MiniMIX-C guard column with an injection volume of 20 μL.

5. 1,3-dioxolane copolymer according to any one of claims 1 to 4, having a dynamic viscosity at 25°C, measured at 25°C with an Anton Paar MCR 320 rotational viscometer and evaluated by a graphical plot of viscosity against shear stress, of between 50 mPas and 500 Pas.

6. A method for preparing a 1,3-dioxolane copolymer of general formula I, comprising the steps of: A process comprising the step of copolymerizing a 1,3-dioxolane with an alkyl-substituted 1,3-dioxolane of general formula II in the presence of a Lewis acid or a Bronsted acid. H-[O-CH ２ -O-CH ２ -CH ２ -] ｘ１ [O-CH ２ -CH ２ P.S. ２ -] ｘ２ [O-CH ２ -O-CHR １ -CHR ２ -] ｙ１ [O-CHR １ -CHR ２ O-CH ２ -] ｙ２ OH (I) (In the formula, x1+x2 is a value between 10 and 2000, R １ and R ２ is hydrogen or C １ ~C １８ is an alkyl group, Unit [O-CH ２ -O-CHR １ -CHR ２ -] ｙ１ and the unit [O-CHR １ -CHR ２ O-CH ２ -] ｙ２ In each of the above, the group R １ or group R ２ At least one of １ ~C １８ is an alkyl group, However, y1+y2 is a value between 3×(x1+x2+y1+y2) / 100 and 50×(x1+x2+y1+y2) / 100.) 【Chemistry 1】

7. 7. The method of claim 6, wherein the acid is selected from boron trifluoride etherate and trifluoromethanesulfonic acid.

8. The method according to claim 6 or 7, wherein the temperature is between 10°C and 60°C.