PL222347B1 - Method for preparing poly (ester-carbonates) with alkylene carbonates - Google Patents

Description

(12) PATENT DESCRIPTION (19) PL (11) 222347 (13) B1 (21) Application number: 400930 (51) Int.Cl.

C08G 63/64 (2006.01) C08G 64/30 (2006.01) (22) Date of notification: 26/09/2012 (54) Method for producing poly (ester-carbonates) from alkylene carbonates

(73) The right holder of the patent: WARSAW UNIVERSITY OF TECHNOLOGY, Warsaw, PL (43) Application was announced: March 31, 2014 BUP 07/14 (72) Inventor (s): (45) The grant of the patent was announced: GABRIEL ROKICKI, Warsaw, PL MAGDALENA MAZUREK, Warsaw, PL PAWEŁ PARZUCHOWSKI, Warsaw, PL ZBIGNIEW FLORJAŃCZYK, Piastów, PL 29.07.2016 WUP 07/16 (74) Representative: item. stalemate. Grażyna Padee

PL 222 347 B1

Description of the invention

The subject of the invention is a two-step process for the production of poly (ester-carbonates) by the phosgene-free method using alkylene carbonates as the source of carbonate bonds. The produced poly (ester-carbonates) can be used as biodegradable materials with a limited degradation rate and a regulated content of carbonate units. Low molecular weight poly (ester-carbonates) with terminal hydroxyl groups can be used in the production of polyurethane elastomers.

Aliphatic poly (ester-carbonates), due to their biocompatibility and biodegradability, are known to be used, for example, in in medicine as resorbable surgical threads and tissue scaffolds. They can also be used for the production of biodegradable packaging materials. They are most often obtained by copolymerization of trimethylene carbonate with cyclic esters such as epsilon-caprolactone, glycolide and L, L-lactide.

Known from the publication of Pospiech et al. in Biomacromolecules 6, 439, 2005, the method of copoly (ester-carbonate) synthesis consists in the copolymerization of L, L-lactide with trimethylene carbonate in the presence of a cyclic bifunctional 2,2-dibutyl-2-stanna-1,3-oxepane initiator. The obtained copolymers are characterized by a triblock structure. Kricheldorf and Rost in their work published in Macromolecules 38, 8220, 2005 used bismuth (III) hexanoate as initiator for the terpolymerization of L, L-lactide, ε-caprolactone and trimethylene carbonate, and Yang et al. described a method of obtaining poly (ester-carbonate) based on the copolymerization of trimethylene carbonate with D, L-lactide in the presence of zinc (II) lactate.

There are also known methods of obtaining poly (ester-carbonates) using other six-membered cyclic carbonates. Xu, Liu and Zhuo in their work published in J. Appl. Polym. Sci. 101, 1988, 2006 described the copolymerization of D, L-lactide with a cyclic carbonate having a rigid substituent: 9-phenyl-2,4,8,10-tetraspiro [5,5] undecan-3-one carried out in the presence of tin (II) octoate . Wolinski et al. for coplymerization with ε-caprolactone, they used a cyclic hexagonal carbonate with a benzyloxy group: 5-benzyloxy-1,3-dioxan-2-one, as described in Macromolecules 40, 7065, 2007. Zhu et al. for copolymerization with D, L-lactide, they used the substituted six-membered cyclic carbonate - 5-methyl-5-methoxycarbonyl-1,3-dioxan-2-one (Eur. Polym. J. 45, 1868, 2009). Another type of six-membered cyclic carbonate used for copolymerization is known from Weiser, Zawaneh and Putam in Biomacromolecules 12, 977, 2011. The authors used 5,5-dimethoxy-1,3-dioxan-2-one in copolymerization with D, L-lactide catalyzed by tin (II) octanoate.

Yank et al. described in Biomacromolecules 5, 2258, 2004 the possibility of obtaining poly (estercarbonates) by a mixed method: first they obtained poly (ethylene tetram succinate) by polycondensation, and then, using it as a macro-initiator, polymerized various cyclic six-membered carbonates, such as trimethylene carbonate, neopentyl carbonate, or 5-benzyloxy-1,3-dioxan-2-one.

There are also known methods of producing poly (ester-carbonates) by polycondensation with the use of phosgene and its derivatives, such as bischloroformates. These copolymers by Vincenzi et al. described in Macromol. Biosci. 1, 164, 2001. Instead of phosgene, Okada, Yokoe and Aoi used diphenyl carbonate and diphenyl sebacate as the source of carbonate bonds as described in J. Appl. Polym. Sci. 86, 872, 2002.

The European patent EP 1277779 B1 of 2004 and US patent 6667381 of 2003 disclose a method of obtaining aliphatic poly (ester-carbonates) from oligoesters of succinic and maleic acid with 1,4-butanediol by reaction with diphenyl carbonate catalyzed by typical reaction catalysts transesterification.

Aliphatic poly (ester-carbonates) can be obtained by enzymatic polycondensation. Described in Macromolecules, 41, 2008, 4671 by Jing et al. poly (tetramethylene succinate-co-carbonate) with a different ratio of carbonate to succinate units was obtained from diethyl carbonate, diethyl succinate and 1,4-butanediol in a two-step reaction catalyzed by the enzyme CALB. The molecular weights of the polymers ranged from 14,000 to 59,400. The highest molecular weight was obtained with a molar ratio of diethyl carbonate to diethyl succinate of 1 to 1. Unfortunately, the synthesis of the polymer is long, which makes the process not very economical. The first step of the reaction was carried out at a temperature of 50-100 ° C under a pressure of 600 mmHg for 18-24 hours. The pressure was then reduced to 1-5 mmHg and the reaction was continued under these conditions for another 24-60 hours. is associated with the high volatility of diethyl carbonate.

Aromatic poly (ester-carbonates) are obtained with the use of phosgene, diphenyl carbonate or mixed methyl phenyl carbonate. It is known from US patent 4,194,038 of

PL 222 347 B1

1980 method of obtaining aromatic poly (ester-carbonates) from bisphenol A, terephthalic acid and phosgene. The obtained polymer had a tensile strength equal to 26.9 MPa.

Likewise, aromatic poly (ester-carbonates) were obtained from phosgene and disodium terephthalic or isophthalic acid in an interface reaction as described in European patent EP 0040315 B1 of 1984.

US Patent 5,066,766 of 1991 discloses a method of obtaining aromatic poly (estercarbonates) by reacting bisphenol A, dimethyl terephthalate and methylphenyl carbonate. The polycondensation process was carried out in the presence of tetra / zopropoxytitanium (IV) at a temperature of 250 ° C, under nitrogen flow, for 3 hours and for 5 minutes at 350 ° C under a reduced pressure of 0.2 torr. The obtained polymer had an intrinsic viscosity equal to 0.63.

The above-described methods of obtaining poly (ester-carbonates) based on copolymerization of trimethylene carbonate or its derivatives require the use of an expensive monomer, which is trimethylene carbonate, which is obtained with the use of the phosgene derivative - ethyl chloroformate. This method generates stoichiometric amounts of environmentally harmful chlorides. The use of diphenyl carbonate or methyl phenyl carbonate in the reaction is in turn associated with the use of phosgene in the synthesis stage of carbonate monomers. The direct use of diethyl carbonate for the synthesis of poly (estercarbonates), due to its low boiling point, requires long-term polycondensation lasting several dozen hours at a relatively low temperature, not exceeding 100 ° C.

The method according to the invention avoids the above-mentioned difficulties. The polymers obtained by the process according to the invention are characterized by an extremely light color.

A method for producing poly (ester-carbonates) by a method using alkylene carbonates such as ethylene carbonate or propylene carbonate as the source of ester bonds is characterized in that, in a first step, a dicarboxylic acid or dimethyl or diethyl ester of a dicarboxylic, aliphatic or aromatic acid or a mixture thereof reacted with an α, ω-diol or a mixture of diols in a molar ratio ranging from 1: 2.6 to 1: 21.5 in the presence of a transesterification catalyst, at a temperature of 160-200 ° C, in a flow of inert gas, receiving water or methanol or ethanol as a by-product, resulting in the bis (hydroxyalkyl) ester of the dicarboxylic acid and unreacted diol. Then, in the second step, propylene carbonate or ethyl ene carbonate in a molar ratio to the bis (hydroxyalkyl) dicarboxylic acid ester from 1: 1.1 to 4: 1 and the azeotroping solvent are added in such an amount as to maintain the boiling point of the reaction mixture within the limits 155-180 ° C and the reaction is carried out by azeotroping 1,2-propylene or ethylene glycol. At the last stage, the azeotroping solvent is distilled off, first under normal pressure, and then by gradually reducing the pressure over 0.5 to 5 hours to a range of 0.1 to 1.0 mbar and gradually raising the temperature over a period of 1 to 5 hours. 5 hours, ranges from 200 to 220 ° C. Under these conditions, polycondensation takes place with the distillation of excess α, ω-diol, which leads to the achievement of the desired molecular weight of the poly (ester-carbonate).

The dicarboxylic acid used is preferably adipic acid, succinic acid, sebacic acid, fumaric acid, maleic acid, terephthalic acid, isophthalic acid or mixtures thereof.

As the α, ω-diol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol or mixtures thereof are preferably used.

As the transesterification catalyst, a tin or titanium catalyst is preferably used, most preferably tin (II) octanoate, dibutyl tin (IV) oxide, tetrabutoxy titanium (IV), tetraisopropoxy titanium (IV), dibutyl tin dilaurate.

The azeotropic removal of 1,2-propylene or ethylene glycol as the lower phase of the condensate is carried out until the 1790 cm absorption band ^- characteristic for the carbonyl group of the five-membered cyclic carbonate in the IR spectrum of the reaction mixture - disappears.

The process according to the invention makes it possible to obtain poly (ester-carbonates) from a cheap monomer, which is propylene or ethylene carbonate - both propylene carbonate and ethylene carbonate can be obtained easily and cheaply using carbon dioxide and oxygen, propylene or ethylene as starting materials. Carbonate monomers are non-toxic, what is more, their synthesis does not require the use of toxic raw materials such as phosgene or its derivatives. The process takes place in a short time and allows to obtain polymer chains containing end hydroxyl groups, thanks to which the products can be used in further reactions, e.g. for the synthesis of polyurethanes. The obtained products are characterized by a light color.

The method according to the invention is presented in more detail in the examples of use.

PL 222 347 B1

Example 1. Poly (tetramethylene terephthalate-co-carbonate) was prepared by a one-pot three-step method. In the first step, 30.00 g (0.1545 mol) dimethyl terephthalate was reacted with 46.15 g (0.5121 mol) 1,4-butanediol in the presence of 0.05 g (0.0002 mol) tetrabutoxy titanium as a catalyst. The reaction was carried out at 180 ° C for 5 h in a 150 cm round three-necked flask equipped with a magnetic stirrer, thermometer, distillation condenser and nitrogen feed valve. 28.3 g of oligo (tetramethylene terephthalate) were obtained in the form of a white solid with a molecular weight of 250. Then the distillation condenser was replaced with an azeotropic head and 28.63 g (0.2804 mol) of propylene ₃ carbonate and 90 cm of n-heptane were added to the flask. as an azeotroping solvent. The distillation condenser was replaced with an azeotropic cap. The reaction was carried out at 175-180 ° C for 7 h, after which the azeotropic head was changed back to the distillation condenser and the azeotroping solvent was distilled off under normal pressure. The reaction was then continued for another 3 hours while gradually reducing the pressure to 0.5 mbar and increasing the temperature to 220 ° C. 51.2 g of poly (ester-carbonate) were obtained in the form of a white solid with a molecular weight of 5410 containing 37 _mol %. carbonate groups.

Example 2 The synthesis of poly (tetramethylene succinate-co-carbonate) was carried out analogously to that described in example 1, except that 21.52 g (0.1473 mol) of dimethyl succinate was used instead of 30.00 g (0.1545 mol). ) dimethyl terephthalate and 52.68 g (0.5846 mol) instead of 46.15 g (0.5121 mol) 1,4-butanediol. 30.0 g of oligo (tetramethylene succinate) was obtained in the form of a cream solid with a molecular weight of 165. The second reaction step was also carried out analogously to that described in example 1, except that 37.12 g (0.3636 mol) was added to the flask instead of 28 . 63 g (0.2804 mol) propylene carbonate. 51.2 g of poly (ester-carbonate) were obtained in the form of a cream solid with a molecular weight of 3810 containing 42 _mol %. carbonate groups.

Example 1: The synthesis of poly (pentamethylene terephthalate-co-carbonate) was carried out analogously to that described in Example 1, except that 60.80 g (0.5846 mol) were used in the first reaction step

1,5-pentanediol instead of 52.68 g (0.5846 mol) 1,4-butanediol. 30.3 g of oligo (pentamethylene terephthalate) were obtained in the form of a colorless liquid of high viscosity and molecular weight 310. The second stage of the reaction was carried out analogously to that described in Example 1 by adding 28.63 g (0.2804 mol) of propylene carbonate. 57.12 g of poly (ester-carbonate) were obtained in the form of a colorless liquid with a very high viscosity and a molecular weight of 4300 containing 35 mol%. carbonate groups.

Example 4 The first step of the synthesis of poly (pentamethylene terephthalate-co-carbonate) was carried out analogously to that described in example 3. 31.8 g of oligo (pentamethylene terephthalate) was obtained in the form of a colorless liquid with high viscosity and molecular weight 405. Second step The reaction was carried out analogously to that described in Example 1, except that 25.93 g (0.2944 mol) of ethylene carbonate was added instead of 28.63 g (0.2804 mol) of propylene carbonate. 49.2 g of poly (ester-carbonate) was obtained in the form of a colorless liquid with a very high viscosity and a molecular weight of 4120 containing 29 mol%. carbonate groups.

Example 5 The synthesis of oligo (hexamethylene adipate-co-carbonate) was carried out analogously to that described in Example 1, except that in the first step 15.56 g (0.106 mol) of adipic acid was used instead of 30.00 g (0 , 1545 mol) dimethyl terephthalate, 64.36 g (0.5454 mol) 1,6-hexanediol instead of 46.15 g (0.5121 mol) 1,4-butanediol and 0.04 g (0.0002 mol) octanoate of tin (II) in place of 0.03 g (0.0001 mol) of tetrabutoxy titanium. 33.3 g of oligo (hexamethylene adipate) was obtained in the form of a cream-colored solid with a molecular weight of 220. The second stage of the reaction was carried out analogously to that described in example 1, except that 33.94 g (0.3325 mol) was added to the flask instead of 28.63 g (0.2804 mol) of propylene carbonate. 65.8 g of poly (ester-carbonate) were obtained in the form of a light yellow solid with a molecular weight of 3185 containing 35 mol%. carbonate groups.

Example 6 The synthesis of poly (tetramethylene terephthalate-co-carbonate-co-carbonate) was carried out analogously to that described in Example 1, except that in the first reaction step 15.53 g (0.0800 mol) were used instead of 30.00 g (0.1545 mol) dimethyl terephthalate, 27.0 g (0.2999 mol) instead of 46.15 g (0.5121 mol) 1,4-butanediol and additionally 6.97 g (0.0400 mol) dimethyl adipate . 23.5 g of oligo (tetramethylene adipate-co-terephthalate) were obtained in the form of a white solid with a molecular weight of 505 g / mol. The second step of the reaction was analogous to that described in Example 1, except that 4.64 g (0.0400 mol) was added to the flask instead of 28.63 g (0.2804 mol) of propylene carbonate. 13.0 g of poly (ester-carbonate) were obtained in the form of a light yellow solid with a molecular weight of 4550 containing 23 mol%. carbonate groups, 20 mole% adipine groups and 57 mole%. terephthalic groups.

PL 222 347 B1

Example 7 The synthesis of oligo (tetramethylene-co-pentamethylene sebacate-co-carbonate) was carried out analogously to that described in Example 1, except that 3.84 g (0.0190 mol) of sebacic acid were used in the first reaction step instead of 30.00 g (0.1545 mol) dimethyl terephthalate, 3.51 g (0.0390 mol) instead of 46.15 g (0.5121 mol) 1,4-butanediol and additionally 4.06 g 1.5- pentanediol. 6.36 g of oligo (tetramethylene-co-pentamethylene sebacate) was obtained in the form of a very viscous liquid with a cream color and a molecular weight of 360. The second reaction step was carried out analogously to that described in example 1, except that 4.08 g (0 0.0400 mol) in place of 28.63 g (0.2804 mol) of propylene carbonate. 8.29 g of poly (ester-carbonate) were obtained in the form of a viscous liquid with a cream color and a molecular weight of 2450 containing 42 _mol %. carbonate groups.

Example 8 The synthesis of poly (decamethylene succinate-co-carbonate) was carried out analogously to that described in Example 1, except that in the first step of the reaction 12.92 g (0.0884 mol) of dimethyl succinate was used instead of 30.00 g ( 0.1545 mol) dimethyl terephthalate, 61.04 g (0.3508 mol) 1,10-decanediol instead of 46.15 g (0.5121 mol) 1,4-butanediol and 0.05 g (0.0002 mol) dibutyltin oxide instead of 0.05 g (0.0002 mol) tetrabutoxy titanium. 24.8 g of oligo (decamethylene succinate) was obtained in the form of a cream solid with a molecular weight of 283. The second reaction step was also carried out analogously to that described in example 1, except that 19.78 g (0.1938 mol) were added to the flask instead of 28 . 63 g (0.2804 mol) propylene carbonate. 37.2 g of poly (ester-carbonate) were obtained in the form of a cream-colored solid with a molecular weight of 1890 containing 39 mol%. carbonate groups.

Example 9 The synthesis of poly (tetramethylene succinate-co-carbonate) was carried out analogously to that described in Example 1, except that 20.46 g (0.1400 mol) of dimethyl terephthalate were used instead of 30.00 g (0.1545 mol) of dimethyl terephthalate. ) of dimethyl succinate and 41.64 g (0.4620 mol) of 1,4-butanediol were used instead of 46.15 g (0.5121 mol). 27.4 g of oligo (tetramethylene succinate) were obtained in the form of a cream solid with a molecular weight of 215. The second step of the reaction was also carried out analogously to that described in example 1, except that 28.06 g (0.3186 mol) of ethylene carbonate were added to the flask. instead of 28.63 g (0.2804 mol) of propylene carbonate. 48.3 g of poly (ester-carbonate) were obtained in the form of a cream solid with a molecular weight of 3620 containing 67 mol%. carbonate groups.

Example 10 The synthesis of oligo (nonamethylene adipate-co-carbonate) was carried out analogously to that described in Example 1, except that in the first step 15.56 g (0.1064 mol) of adipic acid was used instead of 30.00 g ( 0.1545 mol) dimethyl terephthalate and 87.40 g (0.5454 mol) 1.9-nonanediol instead of 46.15 g (0.5121 mol) 1,4-butanediol. 41.3 g of oligo (nonamethylene adipate) was obtained in the form of a cream-colored solid with a molecular weight of 280. The second stage of the reaction was carried out analogously to that described in example 1, except that 33.94 g (0.3325 mol) was added to the flask instead of 28.63 g (0.2804 mol) of propylene carbonate. 74.8 g of poly (estercarbonate) were obtained in the form of a light yellow solid with a molecular weight of 3565 containing 52 _mol %. carbonate groups.

Example 11 The synthesis of poly (dodecamethylene terephthalate-co-carbonate) was carried out analogously to that described in Example 1, except that 118.09 g (0.5846 mol) of 1,12-dodecanediol were used in the first step of the reaction instead of 52. 68 g (0.5846 mol) 1,4-butanediol. 61.2 g of oligo (dodecamethylene terephthalate) was obtained in the form of a colorless liquid of high viscosity with a molecular weight of 415. The second stage of the reaction was carried out analogously to that described in Example 1, by adding 28.63 g (0.2804 mol) of propylene carbonate. 78.1 g of poly (ester-carbonate) were obtained in the form of a colorless liquid with a very high viscosity and a molecular weight of 3500 containing 47 mol%. carbonate groups.

Claims (5)

Patent claims A method for producing poly (ester-carbonates) using alkylene carbonates, dicarboxylic acids or their esters and diols, characterized in that a dicarboxylic acid or dimethyl or diethyl ester of a dicarboxylic, aliphatic or aromatic acid or mixtures thereof is reacted with α, ω -diol or a mixture of diols in a molar ratio ranging from 1: 2.6 to 1: 21.5 in the presence of a transesterification catalyst, at a temperature of 160-200 ° C, in a flow of inert gas, receiving water or methanol or ethanol as a by-product, to obtain the bis (hydroxyalkyl) ester of the dicarboxylic acid and the unreacted diol, and then the propylene carbonate or ethylene carbonate is added in a molar ratio to the bis (hydroxyalkyl) dicarboxylic acid ester of 1: 1.1 to 4: 1 and the azeotroping solvent in enough to keep the tem6 The boiling point of the reaction mixture is between 155-180 ° C and the reaction is carried out by receiving 1,2-propylene glycol or ethylene glycol azeotropically, and then the azeotroping solvent is distilled off, first under normal pressure, and then gradually reducing the pressure over time. 0.5 to 5 hours, to the range of 0.1 to 1 mbar, and gradually increasing the temperature, over a period of 1 to 5 hours, to the range of 200 to 220 ° C. 2. The method according to p. The process of claim 1, wherein the dicarboxylic acid is adipic acid, succinic acid, sebacic acid, fumaric acid, maleic acid, terephthalic acid, isophthalic acid or mixtures thereof. 3. The method according to p. A process as claimed in claim 1, characterized in that 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol or mixtures thereof. 4. The method according to p. The process of claim 1, wherein the transesterification catalyst is a tin or titanium catalyst. 5. The method according to p. A process as claimed in claim 1 or 4, characterized in that tin (II) octanoate, dibutyltin (IV) oxide, tetrabutoxy titanium (IV), tetraisopropoxytitanium (IV), dibutyl tin dilaurate are used as the transesterification catalyst.