Method for preparing alkyl poly (3-hydroxypropionate), alkyl poly (3-hydroxypropionate) and composition comprising same

Abstract

The present disclosure provides a method for preparing an alkyl poly (3-hydroxypropionate), an alkyl poly (3-hydroxypropionate), and a composition comprising the same, the method comprising: subjecting an alkyl-3-hydroxypropionate to polycondensation to prepare an alkyl poly (3-hydroxypropionate), where the alkyl-3-hydroxypropionate has 2 to 20 carbon atoms in the alkyl group.

Description

Technical Field

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2022-0183172 filed in the Korean Intellectual Property Office on December 23, 2023, the disclosure of which is incorporated herein by reference in its entirety.

[0003] The present disclosure relates to methods for preparing alkyl poly(3-hydroxypropionates), alkyl poly(3-hydroxypropionates), and compositions containing the same. Background Art

[0004] Poly(3-hydroxypropionic acid) is a biodegradable polymer that not only has the property of being resistant to breakage but also has excellent mechanical properties, and therefore has attracted attention as an environmentally friendly material.

[0005] Poly(3-hydroxypropionic acid) is prepared by the polycondensation of 3-hydroxypropionic acid (3-HP), among which the method of preparing 3-hydroxypropionic acid by microbial fermentation has attracted attention as an environmentally friendly bioprocess.

[0006] However, when 3-hydroxypropionic acid is prepared by microbial fermentation, other byproducts besides 3-hydroxypropionic acid are also produced in the process of fermenting the microorganisms, and therefore, various processes are required to separate and purify 3-hydroxypropionic acid from the fermented liquid. In particular, 3-hydroxypropionic acid exhibits high hydrophilicity and has high solubility and reactivity in water, and therefore, separation and purification are not easy.

[0007] As an example for recovering 3-hydroxypropionic acid, 3-hydroxypropionic acid can be converted into alkyl-3-hydroxypropionic acid ester and purified, but additional steps such as removing the alkyl group therefrom are required. Summary of the invention

[0008] Technical issues

[0009] An object of the present disclosure is to provide a method for preparing alkyl poly(3-hydroxypropionate) by polycondensation of alkyl-3-hydroxypropionate, the alkyl poly(3-hydroxypropionate) prepared thereby, and a composition containing the same.

[0010] Technical Solution

[0011] According to one embodiment of the present disclosure, there is provided a method for preparing an alkyl poly(3-hydroxypropionate), the method comprising: subjecting an alkyl-3-hydroxypropionate to polycondensation to prepare an alkyl poly(3-hydroxypropionate) represented by the following Chemical Formula 1, wherein the alkyl-3-hydroxypropionate has 2 to 20 carbon atoms in the alkyl group.

[0012] According to another embodiment of the present disclosure, an alkyl poly (3-hydroxypropionate) represented by the following Chemical Formula 1 is provided.

[0013] According to yet another embodiment of the present disclosure, provided is an alkyl poly(3-hydroxypropionate) composition including: an alkyl poly(3-hydroxypropionate) represented by the following Chemical Formula 1 and an alcohol having 2 to 20 carbon atoms.

[0014] Now, a method for preparing an alkyl poly(3-hydroxypropionate), an alkyl poly(3-hydroxypropionate), and a composition including the same according to specific embodiments of the present disclosure will be described in more detail.

[0015] In addition, unless explicitly stated as a sequential or continuous order or otherwise stated, the steps constituting the preparation methods described herein should not be interpreted as being limited to the order of one step and other steps constituting a preparation method described herein. Therefore, the order of the constituent steps of the preparation method can be changed within the scope that can be easily understood by those skilled in the art, and in this case, the changes that are obvious to those skilled in the art are also included in the scope of the present invention.

[0016] Unless particularly mentioned herein, the term “include” or “comprising” means that some elements (or components) are included without any limitation, and should not be interpreted as excluding the addition of other elements (or components).

[0017] In addition, unless otherwise specified herein, the weight average molecular weight and number average molecular weight of alkyl poly (3-hydroxypropionate) etc. can be measured using gel permeation chromatography (GPC). Specifically, the polymer or copolymer is dissolved in chloroform to a concentration of 1 mg / ml, and then 100 μl of the solution is injected into the GPC, and GPC analysis is performed at 40°C. At this time, chloroform is used as the mobile phase for GPC, with a flow rate of 1.0 mL / min, and the column used is two Agilent Mixed-B units connected in series. RI detector is used as a detector. The value of Mw can be obtained using a calibration curve formed using a polystyrene standard sample. Twelve polystyrene standard samples having weight average molecular weights of 162 g / mol, 580 g / mol, 1,180 g / mol, 4,870 g / mol, 9,310 g / mol, 17,120 g / mol, 75,050 g / mol, 200,500 g / mol, 448,500 g / mol, 10,690,000 g / mol, 3,022,000 g / mol, and 6,545,000 g / mol were used.

[0018] According to one embodiment of the present disclosure, there is provided a method for preparing an alkyl poly(3-hydroxypropionate), the method comprising: subjecting an alkyl-3-hydroxypropionate to polycondensation to prepare an alkyl poly(3-hydroxypropionate) represented by the following Chemical Formula 1, wherein the alkyl-3-hydroxypropionate has 2 to 20 carbon atoms in the alkyl group.

[0019] [Chemical formula 1]

[0020]

[0021] Wherein in Chemical Formula 1,

[0022] R is C n H 2n+1 A linear or branched alkyl group represented by (wherein n is an integer from 2 to 20), and

[0023] m is an integer of 10 or more.

[0024] The present inventors have found that when alkyl poly(3-hydroxypropionate) is prepared by polycondensation of alkyl-3-hydroxypropionic acid ester, an alcohol having a boiling point lower than that of water is produced as a polycondensation by-product, so that the by-product can be effectively removed, and the finally prepared alkyl poly(3-hydroxypropionate) has a structure in which a carboxyl group (-COOH) is terminated with an alkyl group, so that the acid value of the polymer is low, the content of vinyl groups at the terminal groups is low, and the yield of the final recovery is also excellent, and the present disclosure has been completed.

[0025] In the method for preparing an alkyl poly(3-hydroxypropionate) according to one embodiment, the alkyl-3-hydroxypropionate may be subjected to polycondensation to prepare the alkyl poly(3-hydroxypropionate) represented by Chemical Formula 1.

[0026] When alkyl-3-hydroxypropionic acid ester is subjected to polycondensation to prepare alkyl poly(3-hydroxypropionic acid ester), alcohol is produced as a polycondensation by-product. However, since this alcohol has a lower boiling point than water, it can be effectively removed even at low temperatures, the content of the by-products finally produced is small, and the water removal step conventionally involved in the production of poly(3-hydroxypropionic acid ester) can be omitted.

[0027] In addition, the alkyl poly (3-hydroxypropionate) has a structure in which the carboxyl group (carboxylic acid group) at the terminal group is substituted with an alkyl ester, and as a result, the carboxyl terminal group is blocked, so that the acid value can be reduced. As the acid value of the alkyl poly (3-hydroxypropionate) is reduced, the storage stability of the polymer can be improved, and the possibility of side reactions can be reduced. In addition, in order to control the acid value of the polymer, an additive for reducing the acid value is conventionally added, but the preparation method according to one embodiment can reduce the acid value without adding an additional additive, thereby reducing the occurrence of by-products.

[0028] Meanwhile, the acid value of the alkyl poly(3-hydroxypropionate) may show different trends according to the number average molecular weight. For example, when the number average molecular weight of the alkyl poly(3-hydroxypropionate) is greater than 3,000 g / mol, the acid value may be higher as the number average molecular weight is lower.

[0029] However, even if the number average molecular weight exceeds 3,000 g / mol, the alkyl poly (3-hydroxypropionate) prepared by the preparation method according to one embodiment can also show a low acid value of 300.0 meq / Kg or less. For example, the acid value of the alkyl poly (3-hydroxypropionate) having a number average molecular weight of more than 3,000 g / mol and 8,000 g / mol or less can be 300.0 meq / Kg or less, 1.0 meq / Kg or more and 290.0 meq / Kg or less, and 10.0 meq / Kg or more, 20.0 meq / Kg or more, 30.0 meq / Kg or more, 50.0 meq / Kg or more, and 280.0 meq / Kg or less, 270.0 meq / Kg or less, 250.0 meq / Kg or less, 230.0 meq / Kg or less, or 210.0 meq / Kg or less. In addition, the acid value of the alkyl poly(3-hydroxypropionate) having a number average molecular weight of greater than 8,000 g / mol and 30,000 g / mol or less may be 150.0 meq / Kg or less, or 1.0 meq / Kg or more and 140.0 meq / Kg or less, and 10.0 meq / Kg or more, 20.0 meq / Kg or more and 145.0 meq / Kg or less, 140.0 meq / Kg or less, 135.0 meq / Kg or less, or 130.0 meq / Kg or less.

[0030] Meanwhile, the acid value of the alkyl poly(3-hydroxypropionate) having a number average molecular weight of 300 g / mol or more and 3,000 g / mol or less may be 1.0 meq / Kg or more and 333.0 meq / Kg or less, and 2.0 meq / Kg or more, 3.0 meq / Kg or more, or 300.0 meq / Kg or less, 200.0 meq / Kg or less, 100.0 meq / Kg or less, 70.0 meq / Kg or less, 50.0 meq / Kg or less, 30.0 meq / Kg or less, or 20.0 meq / Kg or less.

[0031] In addition, alkyl poly(3-hydroxypropionate) is prepared by polycondensation of alkyl 3-hydroxypropionate, such that the content of vinyl at the ends of the alkyl poly(3-hydroxypropionate) can be 40 mol% or less. For example, the content of vinyl at the ends of the alkyl poly(3-hydroxypropionate) can be 30 mol% or less, 20 mol% or less, 15 mol% or less, 10 mol% or less, or 5 mol% or less, or 0.01 mol% or more, 0.02 mol% or more, 0.03 mol% or more, 0.04 mol% or more, or 0.05 mol% or more.

[0032] The alkyl poly(3-hydroxypropionate) can have hydroxyl, carboxyl, vinyl, etc. as end groups, but since the alkyl poly(3-hydroxypropionate) is prepared by polycondensation of alkyl 3-hydroxypropionate, the possibility of vinyl existing in the end groups is low. Vinyl is generated due to side reactions occurring during the polymerization of 3-hydroxypropionic acid into poly(3-hydroxypropionic acid), where vinyl acts as a factor that disrupts the equivalent ratio in the polycondensation, and the equivalent ratio of each functional group (hydroxyl, carboxyl) is important, thereby inhibiting the reaction rate and making it difficult to obtain a polymer with a high molecular weight. In addition, if vinyl exists in the alkyl poly(3-hydroxypropionate), there is a problem that chain extension caused by further modification of the alkyl poly(3-hydroxypropionate) cannot occur favorably. Therefore, since the amount of vinyl in the end groups of the alkyl poly(3-hydroxypropionate) is small, it has the advantage of fundamentally reducing the above-mentioned disadvantages.

[0033] The content of the end groups of poly(3-hydroxypropionic acid) can be determined by calculating the ratio of vinyl to the total end groups via 1 1H-NMR measurement using a Buker 500 MHz NMR model device. For example, the polymer can be dissolved at a concentration of 8 mg / ml in d-CDCl 3 and measured, and calculated according to the following Mathematical Formula 1.

[0034] [Mathematical Formula 1]

[0035]

[0036] In Mathematical Formula 1,

[0037] a is the area value of H in C═C at 6.3 ppm 1 and

[0038] b is the area value of H in HO-CH 2 - 2 and

[0039] in C═C 1The area value of H is the area value of the hydrogen (H) on the side closer to the carbonyl group among the hydrogens (H) of the double bond of the vinyl group, and the area value of HO-CH 2 -middle 2 The area value of H may be the area value of two hydrogens substituted on the carbon to which the terminal hydroxyl group is connected.

[0040] The alkyl-3-hydroxypropionate may have 2 to 20, 2 to 10, 2 to 8, or 2 to 6 carbon atoms in the alkyl group, and examples thereof may be ethyl, n-propyl, isopropyl, n-butyl, or tert-butyl.

[0041] In addition, the alkyl poly(3-hydroxypropionate) may be represented by Chemical Formula 1 below.

[0042] [Chemical formula 1]

[0043]

[0044] R is an alkyl group that terminates the carboxyl group of poly(3-hydroxypropionate), and may be derived from the alkyl group of alkyl-3-hydroxypropionate. For example, R may be composed of C n H 2n+1 A linear or branched alkyl group represented by (wherein n is an integer from 2 to 20), composed of C n H 2n+1 A linear or branched alkyl group represented by (wherein n is an integer from 2 to 10), or a C n H 2n+1 represents a linear or branched alkyl group (wherein n is an integer of 2 to 6), and more specifically, it may be an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, or a tert-butyl group.

[0045] m represents the number of repeating structures, and for example, m may be an integer of 10 or more, or an integer of 10 to 600.

[0046] The weight average molecular weight of the alkyl poly (3-hydroxypropionate) may be 500 g / mol or more, 600 g / mol or more, 1,000 g / mol or more, 2,000 g / mol or more, 3,000 g / mol or more, or 5,000 g / mol or more, and 100,000 g / mol or less, 80,000 g / mol or less, 70,000 g / mol or less, 60,000 g / mol or less, 50,000 g / mol or less, 25,000 g / mol or less, or 20,000 g / mol or less. If the weight average molecular weight of the alkyl poly (3-hydroxypropionate) is too low, its crystallinity is low and does not exist in a solid state, and may be easily broken and have reduced strength, while if the weight average molecular weight is too high, it may have high viscosity and be difficult to process.

[0047] The number average molecular weight of the alkyl poly (3-hydroxypropionate) may be 300 g / mol or more, 400 g / mol or more, 500 g / mol or more, 1,000 g / mol or more, 2,000 g / mol or more, 3,000 g / mol or more, or 5,000 g / mol or more, and 30,000 g / mol or less, 25,000 g / mol or less, 20,000 g / mol or less, 15,000 g / mol or less, 10,000 g / mol or less, 9,000 g / mol or less, or 8,000 g / mol or less. If the number average molecular weight of the alkyl poly (3-hydroxypropionate) is too low, its crystallinity is low and does not exist in a solid state, and may be easily broken and have reduced strength, while if the number average molecular weight is too high, it may have high viscosity and be difficult to process.

[0048] In addition, the alkyl poly (3-hydroxypropionate) can have a certain number average molecular weight and a molecular weight distribution (Mw / Mn) of 1.0 to 35.0. More preferably, the molecular weight distribution of the poly (3-hydroxypropionic acid) according to the present disclosure can be 1.3 or more, 1.4 or more, 1.7 or more, 1.8 or more, or 2.0 or more, and 35.0 or less, 30.0 or less, 25.0 or less, 20.0 or less, 11.0 or less, 5.0 or less, 3.0 or less, or 2.5 or less.

[0049] The alkyl poly (3-hydroxypropionate) prepared by the preparation method according to one embodiment can be prepared by subjecting the alkyl-3-hydroxypropionate to a polycondensation reaction. Specifically, the polycondensation of the alkyl-3-hydroxypropionate can be performed at a temperature of 50° C. or higher and 250° C. or lower. In addition, the polycondensation can be performed for 6 hours or longer and 30 hours or shorter.

[0050] For example, the polycondensation can be performed at a temperature of 50° C. or more, or 70° C. or more, or 90° C. or more, or 110° C. or more, and at a temperature of 250° C. or less, or 230° C. or less, or 200° C. or less for a period of 6 hours or more, or 8 hours or more, or 10 hours or more, and 30 hours or less, or 28 hours or less, or 26 hours or less. When the polymerization is performed under the above conditions, an alkyl poly(3-hydroxypropionate) having physical properties and a weight average molecular weight within the optimal range to be achieved in the present disclosure can be prepared with excellent yield.

[0051] The polycondensation may be performed in the presence of at least one catalyst selected from the group consisting of a sulfonic acid-based catalyst, a metal oxide, a metal chloride, and a metal alkoxide catalyst.

[0052] The sulfonic acid catalyst may include, but is not limited to, for example, benzenesulfonic acid, n-butylbenzenesulfonic acid, n-octylbenzenesulfonic acid, n-dodecylbenzenesulfonic acid, pentadecylbenzenesulfonic acid, 2,5-dimethylbenzenesulfonic acid, 2,5-dibutylbenzenesulfonic acid, o-aminobenzenesulfonic acid, m-aminobenzenesulfonic acid, p-aminobenzenesulfonic acid, 3-amino-4-hydroxybenzenesulfonic acid, 5-amino-2-methylbenzenesulfonic acid, 3,5-diamino-2,4,6-trimethylbenzenesulfonic acid, 2,4-dinitrobenzenesulfonic acid, p-chlorobenzenesulfonic acid, 2,5-dichlorobenzenesulfonic acid, hydroxynitro Benzenesulfonic acid, aminotoluenesulfonic acid, p-phenolsulfonic acid, aminophenolsulfonic acid, isopropylbenzenesulfonic acid, xylenesulfonic acid, o-cresolsulfonic acid, m-cresolsulfonic acid, p-cresolsulfonic acid, p-toluenesulfonic acid (p-TSA), methanesulfonic acid (m-SA), trifluoromethanesulfonic acid, perfluorobutane-1-sulfonic acid, 2-naphthalenesulfonic acid, p-xylene-4-sulfonic acid, 2-toluenesulfonic acid, 3-toluenesulfonic acid, 2-ethylbenzenesulfonic acid, 3-ethylbenzenesulfonic acid, 4-ethylbenzenesulfonic acid, taurine, cyclopentanesulfonic acid, cyclohexanesulfonic acid, sulfuric acid, camphorsulfonic acid, etc.

[0053] The metal oxide may include, but is not limited to, germanium dioxide, zinc oxide, tin oxide, antimony trioxide, iron trioxide, aluminum trioxide, silicon dioxide, titanium dioxide, and the like.

[0054] The metal alkoxide may include, but is not limited to, for example, titanium butoxide, titanium isopropoxide, aluminum isopropoxide, yttrium isopropoxide, germanium ethoxide, silicon ethoxide, tin octoate, and the like.

[0055] The metal chloride may include, but is not limited to, potassium chloride, calcium chloride, nickel chloride, cobalt chloride, magnesium chloride, manganese chloride, iron chloride, barium chloride, zinc chloride, aluminum chloride, tin chloride, and the like.

[0056] Based on the alkyl-3-hydroxypropionic acid ester, the catalyst can be used in an amount of 0.001 mol% or more and 10 mol% or less. For example, based on the alkyl-3-hydroxypropionic acid ester, the catalyst can be used in an amount of 0.010 mol% or more, or 0.050 mol% or more, and 0.10 mol% or more, or 0.20 mol% or more, or 10 mol% or less, 5 mol% or less, 3 mol% or less, or 1 mol% or less. If the catalyst is used in too small an amount, the polymerization activity may be insufficient, and if the catalyst is used in too large an amount, the amount of residual catalyst may become larger, which may result in decomposition of the polymer or a decrease in molecular weight due to depolymerization such as transesterification.

[0057] In addition, the preparation method according to one embodiment may include: (step 1) melt-polymerizing an alkyl-3-hydroxypropionic acid ester to prepare an alkyl-3-hydroxypropionic acid oligomer; and (step 2) further polymerizing the alkyl-3-hydroxypropionic acid oligomer to prepare an alkyl poly(3-hydroxypropionic acid ester).

[0058] Melt polymerization means that the reactant alkyl-3-hydroxypropionic acid ester and the product alkyl-3-hydroxypropionic acid oligomer remain in a liquid state. For this purpose, in the present disclosure, the reaction temperature of step 1 is adjusted to a temperature of 40°C to 120°C. Although not theoretically limited, the formation of cyclic oligomers is suppressed during the polymerization of alkyl-3-hydroxypropionic acid ester under melt polymerization conditions. Preferably, the reaction temperature of step 1 can be 40°C or higher, 45°C or higher, 50°C or higher, 55°C or higher, 60°C or higher, 65°C or higher, 70°C or higher, 75°C or higher, or 80°C or higher, and 135°C or lower, 130°C or lower, 125°C or lower, 120°C or lower, 115°C or lower, 110°C or lower, 105°C or lower, 100°C or lower, or 95°C or lower.

[0059] Step 1 can be carried out at a pressure of 5 mbar to 200 mbar. When the reaction of step 1 is carried out at such a low pressure, the polymerization of alkyl-3-hydroxypropionic acid ester can be promoted. More preferably, step 1 can be carried out at 6 mbar or more, or 7 mbar or more, and 190 mbar or less, 180 mbar or less, 170 mbar or less, 160 mbar or less, 150 mbar or less, 140 mbar or less, 130 mbar or less, 120 mbar or less, 110 mbar or less, 100 mbar or less, 90 mbar or less, 80 mbar or less, 70 mbar or less, 60 mbar or less, 50 mbar or less, 40 mbar or less, 30 mbar or less, 20 mbar or less, or 10 mbar or less.

[0060] The reaction time of step 1 can be appropriately determined in consideration of the molecular weight, yield, etc. of the generated alkyl-3-hydroxypropionic acid oligomer, and preferably, the reaction is performed for 1 to 5 hours. Within the above reaction time, the molecular weight of the alkyl-3-hydroxypropionic acid oligomer can be increased to an appropriate level, and the production yield can also be improved.

[0061] Furthermore, a catalyst may be added in a predetermined amount during the reaction of step 1. The catalyst has a role of promoting polymerization of the alkyl-3-hydroxypropionic acid ester and simultaneously suppressing the formation of cyclic oligomers during the polymerization process of the alkyl-3-hydroxypropionic acid ester.

[0062] Meanwhile, for the melt polymerization of step 1, if necessary, a step of drying the alkyl-3-hydroxypropionic acid ester may be performed before performing step 1. By drying, moisture present in the alkyl-3-hydroxypropionic acid ester may be removed. At this time, the drying temperature is preferably 40° C. to 95° C., and the drying pressure is preferably 10 mbar to normal pressure, and the drying time is preferably 1 hour to 10 hours.

[0063] In step 2, the alkyl-3-hydroxypropionic acid oligomer may be further polymerized to prepare an alkyl poly(3-hydroxypropionate).

[0064] Since the reactant is an oligomer unlike step 1, step 2 may be performed at an increased polymerization temperature and a further reduced pressure as compared to step 1. Preferably, the polymerization temperature of step 2 may be 50° C. or higher, or 70° C. or higher, or 90° C. or higher and 250° C. or lower, or 230° C. or lower, 200° C. or lower, 180° C. or lower, or 160° C. or lower.

[0065] The pressure of step 2 is 1 mbar or less, and more preferably, the pressure of step 2 is 0.9 mbar or less, 0.8 mbar or less, 0.7 mbar or less, 0.6 mbar or less, 0.5 mbar or less, 0.4 mbar or less, 0.3 mbar or less, 0.25 mbar or less, 0.20 mbar or less, 0.19 mbar or less, or 0.18 mbar or less, and 0.01 mbar or more, 0.02 mbar or more, 0.03 mbar or more, 0.04 mbar or more, 0.05 mbar or more, 0.06 mbar or more, 0.07 mbar or more, 0.08 mbar or more, 0.09 mbar or more, or 0.01 mbar or more.

[0066] The reaction time of step 2 can be appropriately determined in consideration of the molecular weight, yield, etc. of the produced alkyl poly (3-hydroxypropionate), and the reaction is preferably performed for a period of 6 hours or more, or 8 hours or more, or 10 hours or more, and 30 hours or less, or 28 hours or less, or 26 hours or less. Within the above reaction time, the molecular weight of the alkyl poly (3-hydroxypropionate) can be increased to an appropriate level, and the production yield can also be improved.

[0067] Meanwhile, since step 2 is performed after step 1, the catalyst added in step 1 participates in the reaction even in step 2. Therefore, the catalyst previously described in step 1 can also be applied to step 2.

[0068] According to another embodiment of the present disclosure, an alkyl poly (3-hydroxypropionate) represented by the following Chemical Formula 1 is provided.

[0069] [Chemical formula 1]

[0070]

[0071] Wherein in Chemical Formula 1,

[0072] R is C n H 2n+1A linear or branched alkyl group represented by (wherein n is an integer from 2 to 20), and

[0073] m is an integer of 10 or more.

[0074] The alkyl poly(3-hydroxypropionate) may be prepared by the method for preparing an alkyl poly(3-hydroxypropionate) according to one embodiment.

[0075] In addition, the acid value, the content of vinyl groups in the terminal groups, the weight average molecular weight and the number average molecular weight of the alkyl poly(3-hydroxypropionate) are as described above.

[0076] Furthermore, according to yet another embodiment of the present disclosure, provided is an alkyl poly(3-hydroxypropionate) composition including the alkyl poly(3-hydroxypropionate) represented by Chemical Formula 1 and an alcohol having 2 to 20 carbon atoms.

[0077] The composition may be prepared by the method for preparing an alkyl poly(3-hydroxypropionate) according to one embodiment.

[0078] The preparation method prepares poly(3-hydroxypropionate) by polycondensation of alkyl-3-hydroxypropionate, and therefore, may produce alcohols having 2 to 20 carbon atoms as by-products. The alcohols have a lower boiling point than water and can be effectively removed even at low temperatures, so that the content of the by-products finally produced is low, and the water removal process conventionally involved in the preparation of poly(3-hydroxypropionate) can be omitted.

[0079] The alcohol may have 2 to 20 carbon atoms, 2 to 10 carbon atoms, 2 to 8 carbon atoms, or 2 to 6 carbon atoms, and for example, the alcohol may be ethanol, n-propanol, isopropanol, n-butanol, or tert-butanol.

[0080] Beneficial Effects

[0081] The present disclosure provides a method for preparing alkyl poly(3-hydroxypropionate), alkyl poly(3-hydroxypropionate), and a composition comprising the same, wherein the method prepares alkyl poly(3-hydroxypropionate) by polycondensation of alkyl-3-hydroxypropionate and effectively removes by-products such as alcohol, and the acid value of the finally prepared polymer is low and the formation of vinyl groups due to side reactions is small. DETAILED DESCRIPTION

[0082] Hereinafter, embodiments of the present disclosure will be described in detail with reference to examples. However, the following examples are for illustrative purposes only, and the specific embodiments of the present disclosure are not limited to these examples.

[0083] Experimental Example 1

[0084] 15 g of ethyl-3-hydroxypropionate from which water was removed was placed in a reactor, and 0.4 mol% of octyltriamine as a catalyst was added based on the ethyl-3-hydroxypropionate. The temperature and pressure in the reactor were maintained at 90° C. and 10 Torr, respectively, and the reaction was carried out for 2 hours to prepare ethyl-3-hydroxypropionate oligomers. Then, the temperature and pressure in the reactor were adjusted to 90° C. and 0.2 Torr, respectively, and the reaction was carried out for 24 hours to prepare ethyl poly(3-hydroxypropionate).

[0085] Experimental Example 2

[0086] Ethyl poly(3-hydroxypropionate) was prepared in the same manner as in Experimental Example 1, except that p-TSA (p-toluenesulfonic acid) was used instead of octyltriamine.

[0087] Experimental Example 3

[0088] Ethyl poly(3-hydroxypropionate) was prepared in the same manner as in Experimental Example 1, except that tin chloride (SnCl 2 ) instead of octyltriamine.

[0089] <Evaluation>

[0090] 1. Gas chromatography (GC) measurement

[0091] The reaction products of Experimental Examples 1 to 3 were measured by gas chromatography (GC), and the contents of byproducts such as ethanol, ethyl-3-hydroxypropionate, dimer and other byproducts generated other than the final ethyl poly (3-hydroxypropionate) were measured. The results are shown in Table 1 below.

[0092] [Table 1]

[0093] Unit (weight %) Ethanol Ethyl 3-hydroxypropionate Dimer other Experimental Example 1 0.8 99.2 0 0 Experimental Example 2 27.0 47.8 25.2 0 Experimental Example 3 3.6 64.5 31.2 0.7

[0094] According to Table 1, it was determined that in Experimental Examples 2 and 3, the starting material ethyl-3-hydroxypropionate was measured to be less than 64.5 wt %, while in Experimental Example 1, ethyl-3-hydroxypropionate was measured to be 99.2 wt %, so that the condensation reactivity was lower than that in Experimental Examples 2 and 3.

[0095] Example 1

[0096] 15 g of ethyl-3-hydroxypropionate from which water was removed was placed in a reactor, and 19.7 mg of m-SA (methanesulfonic acid) as a catalyst was added at 0.2 mol% based on ethyl-3-hydroxypropionate. The temperature and pressure in the reactor were maintained at 90° C. and 10 Torr, respectively, and the reaction was carried out for 2 hours to prepare ethyl-3-hydroxypropionate oligomers. Then, the temperature and pressure in the reactor were adjusted to 90° C. and 0.2 Torr, respectively, and the reaction was carried out for 24 hours to prepare ethyl poly (3-hydroxypropionate).

[0097] Example 2

[0098] 15 g of tert-butyl-3-hydroxypropionate from which water was removed was placed in a reactor, and 19.7 mg of m-SA (methanesulfonic acid) as a catalyst was added at 0.2 mol% based on tert-butyl-3-hydroxypropionate. The temperature and pressure in the reactor were maintained at 90° C. and 10 Torr, respectively, and the reaction was carried out for 2 hours to prepare ethyl-3-hydroxypropionate oligomers. Then, the temperature and pressure in the reactor were adjusted to 90° C. and 0.2 Torr, respectively, and the reaction was carried out for 24 hours to prepare tert-butyl poly (3-hydroxypropionate).

[0099] Example 3

[0100] Tert-butyl poly(3-hydroxypropionate) was prepared in the same manner as in Example 2, except that 39.4 mg (0.4 mol%) of m-SA (methanesulfonic acid) was used instead of 19.7 mg (0.2 mol%) of m-SA (methanesulfonic acid).

[0101] Example 4

[0102] Tert-butyl poly(3-hydroxypropionate) was prepared in the same manner as in Example 2, except that 63.3 mg (0.2 mol%) of p-TSA was used instead of 19.7 mg (0.2 mol%) of m-SA (methanesulfonic acid).

[0103] Example 5

[0104] Tert-butyl poly(3-hydroxypropionate) was prepared in the same manner as in Example 2, except that 126.6 mg (0.4 mol%) of p-TSA was used instead of 19.7 mg (0.2 mol%) of m-SA (methanesulfonic acid).

[0105] Example 6

[0106] Tert-butyl poly(3-hydroxypropionate) was prepared in the same manner as in Example 5, except that all reaction temperatures were controlled to 120°C.

[0107] Example 7

[0108] Tert-butyl poly(3-hydroxypropionate) was prepared in the same manner as in Example 5, except that all reaction temperatures were controlled to 140°C.

[0109] Example 8

[0110] Tert-butyl poly(3-hydroxypropionate) was prepared in the same manner as in Example 5, except that all reaction temperatures were controlled to 160°C.

[0111] Example 9

[0112] Tert-butyl poly(3-hydroxypropionate) was prepared in the same manner as in Example 5, except that all reaction temperatures were controlled to 180°C.

[0113] Example 10

[0114] 15 g of n-butyl-3-hydroxypropionate from which water was removed was placed in a reactor, and 126.6 mg of p-TSA as a catalyst was added at 0.4 mol% based on n-butyl-3-hydroxypropionate. The temperature and pressure in the reactor were maintained at 90° C. and 10 Torr, respectively, and the reaction was carried out for 2 hours to prepare n-butyl-3-hydroxypropionate oligomers. Then, the temperature and pressure in the reactor were adjusted to 90° C. and 0.2 Torr, respectively, and the reaction was carried out for 24 hours to prepare n-butyl poly (3-hydroxypropionate).

[0115] Embodiment 11

[0116] 15 g of n-butyl-3-hydroxypropionate from which water was removed was placed in a reactor, and titanium butoxide (Ti(BuO)) was added as a catalyst at 0.4 mol% based on the n-butyl-3-hydroxypropionate. 4 ). The temperature and pressure in the reactor were maintained at 90° C. and 10 Torr, respectively, and the reaction was carried out for 2 hours to prepare n-butyl-3-hydroxypropionate oligomer. Then, the temperature and pressure in the reactor were adjusted to 90° C. and 0.2 Torr, respectively, and the reaction was carried out for 24 hours to prepare n-butyl poly (3-hydroxypropionate).

[0117] Example 12

[0118] n-Butyl poly(3-hydroxypropionate) was prepared in the same manner as in Example 11, except that the reaction conditions (90° C. / 0.2 Torr / 24 hours) were adjusted to 120° C. and 0.2 Torr, and the reaction was performed for 8 hours.

[0119] Embodiment 13

[0120] n-Butyl poly(3-hydroxypropionate) was prepared in the same manner as in Example 11, except that the reaction conditions (90° C. / 0.2 Torr / 24 hours) were adjusted to 140° C. and 0.2 Torr, and the reaction was performed for 8 hours.

[0121] Embodiment 14

[0122] n-Butyl poly(3-hydroxypropionate) was prepared in the same manner as in Example 11, except that the reaction conditions (90° C. / 0.2 Torr / 24 hours) were adjusted to 160° C. and 0.2 Torr, and the reaction was performed for 18 hours.

[0123] Embodiment 15

[0124] n-Butyl poly(3-hydroxypropionate) was prepared in the same manner as in Example 11, except that the reaction conditions (90° C. / 0.2 Torr / 24 hours) were adjusted to 180° C. and 0.2 Torr, and the reaction was performed for 8 hours.

[0125] Comparative Example 1

[0126] 15 g of 3-hydroxypropionic acid from which water was removed was placed in a reactor, and 63.3 mg of p-TSA as a catalyst was added at 0.2 mol% based on the 3-hydroxypropionic acid. The temperature and pressure in the reactor were maintained at 90° C. and 10 Torr, respectively, and the reaction was performed for 2 hours to prepare a 3-hydroxypropionate oligomer. Then, the temperature and pressure in the reactor were adjusted to 90° C. and 0.2 Torr, respectively, and the reaction was performed for 24 hours to prepare poly(3-hydroxypropionate).

[0127] Comparative Example 2

[0128] Poly(3-hydroxypropionate) was prepared in the same manner as in Comparative Example 1, except that 19.7 mg (0.2 mol%) of m-SA was used instead of 63.3 mg (0.2 mol%) of p-TSA.

[0129] Comparative Example 3

[0130] 15 g of methyl-3-hydroxypropionate from which water was removed was placed in a reactor, and 19.7 mg of m-SA as a catalyst was added at 0.2 mol% based on the methyl-3-hydroxypropionate. The temperature and pressure in the reactor were maintained at 90° C. and 10 Torr, respectively, and the reaction was performed for 2 hours to prepare a methyl-3-hydroxypropionate oligomer. Then, the temperature and pressure in the reactor were adjusted to 90° C. and 0.2 Torr, respectively, and the reaction was performed for 24 hours to prepare methyl poly(3-hydroxypropionate).

[0131] <Evaluation>

[0132] 1. Gel Permeation Chromatography Measurements

[0133] The weight-average molecular weight, number-average molecular weight, and polydispersity index of the polymers prepared in the examples and comparative examples were measured by gel permeation chromatography (GPC, Waters Alliance e2695), and the results are shown in Table 2 below.

[0134] <GPC analysis conditions>

[0135] The product was dissolved in chloroform to a concentration of 1 mg / ml, then 100 μl of the solution was injected into the GPC, and GPC analysis was performed at 40 °C. At this time, chloroform was used as the mobile phase for GPC, the flow rate was 1.0 mL / minute, and the columns used were two Agilent Mixed-B units connected in series. An RI detector was used as the detector. The value of Mw was obtained using a calibration curve formed with polystyrene standard samples. Twelve polystyrene standard samples with weight-average molecular weights of 162 g / mol, 580 g / mol, 1,180 g / mol, 4,870 g / mol, 9,310 g / mol, 17,120 g / mol, 75,050 g / mol, 200,500 g / mol, 448,500 g / mol, 10,690,000 g / mol, 3,022,000 g / mol, and 6,545,000 g / mol were used.

[0136] 2. Evaluation of yield

[0137] The yields of the polymers prepared in the examples and comparative examples were calculated according to the following Mathematical Formulas 2 and 3, and the results are shown in Table 2 below.

[0138] <Mathematical Formula 2>

[0139] Theoretical value = amount of alkyl-3-hydroxypropionate added (g) * (polymer molecular weight / alkyl-3-hydroxypropionate molecular weight)

[0140] <Mathematical Formula 3>

[0141] Yield (%) = amount of finally prepared polymer / theoretical value * 100

[0142] 3. Analysis of the content of vinyl groups in the end groups

[0143] For the polymers prepared in Examples 1 to 3, 11 and Comparative Examples 1 to 3 above, the ratio of vinyl groups to total end groups was calculated by 1H-NMR measurement using a Buker 500 MHz NMR model device. Specifically, each polymer was dissolved in d-CDCl3 at a concentration of 8 mg / ml and measured, and calculated according to the following Mathematical Formula 1, and the results are shown in Table 2 below. 1 H-NMR measurement 3 and measured, and calculated according to the following Mathematical Formula 1, and the results are shown in Table 2 below.

[0144] [Mathematical formula 1]

[0145]

[0146] In mathematical formula 1,

[0147] a is 6.3 ppm in C=C 1 The area value of H,

[0148] b is 3.8 ppm HO-CH 2 -middle 2 The area value of H.

[0149] 4. Measurement of polymer acid value

[0150] The acid values ​​of the polymers prepared in Examples 1 to 3, 11 and Comparative Examples 1 to 3 were measured according to ASTM D4662 standard, and the results are shown in Table 3 below.

[0151] Specifically, the polymer was titrated using a DGi 116-solvent electrode on a Mettler Toledo T5 apparatus with 0.02 N potassium methoxide solution as the titration solution to analyze the titration point.

[0152] [Table 2]

[0153] Number average molecular weight Weight average molecular weight Polydispersity index Yield (%) Comparative Example 1 9,990 21,180 2.12 89 Comparative Example 2 4,976 10,984 2.20 87 Comparative Example 3 2,248 4,295 1.91 19 Example 1 2,638 5,025 1.90 21 Example 2 7,090 12,094 1.71 72 Example 3 9,948 19,352 1.95 77 Example 4 6,234 11,649 1.87 71 Example 5 9,227 19,627 2.13 96.6 Example 6 3,302 63,858 19.34 98 Example 7 2,326 78,459 33.73 94 Example 8 838 1,577 1.88 75 Example 9 457 664 1.45 39 Example 10 2,331 3,023 1.30 94 Embodiment 11 7,259 14,484 2.00 95 Example 12 1,525 12,450 8.16 88 Embodiment 13 4,615 15,082 3.27 90 Embodiment 14 4,459 12,317 2.76 92 Embodiment 15 3,195 34,947 10.94 89

[0154] [Table 3]

[0155] Number average molecular weight Vinyl content (%) Comparative Example 1 9990 13.8 Comparative Example 2 4976 5.2 Comparative Example 3 2248 0 Example 1 2638 0 Example 2 7090 0 Example 3 9948 0 Embodiment 11 7259 0

[0156] [Table 4]

[0157] Number average molecular weight Acid value (unit: meq / Kg) Comparative Example 1 9990 198.7 Comparative Example 2 4976 344.1 Comparative Example 3 2248 19.4 Example 1 2638 15.2 Example 2 7090 203.1 Example 3 9948 128.3 Embodiment 11 7259 207.5

[0158] Referring to Table 2, it was determined that the polymer of the Examples prepared from ethyl-3-hydroxypropionate, tert-butyl-3-hydroxypropionate, or n-butyl-3-hydroxypropionate was significantly higher in yield than the polymer of Comparative Example 3 prepared from methyl-3-hydroxypropionate. In addition, referring to Table 3, it was determined that unlike Comparative Examples 1 and 2 in which the polymer was prepared from 3-hydroxypropionic acid, the Examples in which the polymer was prepared from alkyl-3-hydroxypropionate did not include a vinyl group in the terminal group of the polymer.

[0159] In addition, referring to Table 4, it was determined that the acid value of the polymer is affected by the number average molecular weight, and although Comparative Example 1 and Example 3 have similar number average molecular weights, the acid value of Example 3 is significantly lower than that of Comparative Example 1. In addition, it was determined that although Example 1 and Comparative Example 3 have similar number average molecular weights, the acid value of Example 1 is lower than that of Comparative Example 3.

Claims

1. A method for preparing an alkyl poly (3-hydroxypropionate), comprising: The alkyl-3-hydroxypropionate is subjected to polycondensation to prepare an alkyl poly(3-hydroxypropionate) represented by the following Chemical Formula 1, wherein the alkyl-3-hydroxypropionate has 2 to 20 carbon atoms in the alkyl group: [Chemical formula 1] Wherein in Chemical Formula 1, R is C n H 2n+1 A linear or branched alkyl group represented by (wherein n is an integer from 2 to 20), and m is an integer of 10 or more.

2. The method for preparing alkyl poly (3-hydroxypropionate) according to claim 1, wherein the polycondensation is carried out in the presence of at least one catalyst selected from the group consisting of sulfonic acid-based catalysts, metal oxides, metal chlorides and metal alkoxide catalysts.

3. The method for preparing alkyl poly (3-hydroxypropionate) according to claim 2, wherein the catalyst is used in an amount of 0.001 mol% or more and 10 mol% or less based on the alkyl-3-hydroxypropionic acid ester.

4. The method for preparing alkyl poly (3-hydroxypropionate) according to claim 1, wherein the polycondensation is performed at a temperature of 50° C. or higher and 250° C. or lower.

5. The method for preparing alkyl poly (3-hydroxypropionate) according to claim 1, wherein the polycondensation is carried out for a period of 6 hours or more and 30 hours or less.

6. The method for preparing alkyl poly (3-hydroxypropionate) according to claim 1, wherein the alkyl poly(3-hydroxypropionate) has a weight average molecular weight of 500 g / mol or more and 100,000 g / mol or less.

7. The method for preparing alkyl poly (3-hydroxypropionate) according to claim 1, wherein the alkyl poly(3-hydroxypropionate) has a number average molecular weight of 300 g / mol or more and 30,000 g / mol or less.

8. The method for preparing alkyl poly (3-hydroxypropionate) according to claim 1, wherein the alkyl poly(3-hydroxypropionate) having a number average molecular weight of 300 g / mol or more and 3,000 g / mol or less has an acid value of 1.0 meq / Kg or more and 333.0 meq / Kg or less, The alkyl poly(3-hydroxypropionate) having a number average molecular weight of greater than 3,000 g / mol and 8,000 g / mol or less has an acid value of 300.0 meq / Kg or less, and The alkyl poly(3-hydroxypropionate) having a number average molecular weight of greater than 8,000 g / mol and 30,000 g / mol or less has an acid value of 150.0 meq / Kg or less.

9. The method for preparing alkyl poly (3-hydroxypropionate) according to claim 1, The alkyl poly (3-hydroxypropionate) has a vinyl content at the terminal of 30 mol% or less.

10. An alkyl poly (3-hydroxypropionate) represented by the following Chemical Formula 1: [Chemical formula 1] Wherein in Chemical Formula 1, R is C n H 2n+1 A linear or branched alkyl group represented by (wherein n is an integer from 2 to 20), and m is an integer of 10 or more.

11. The alkyl poly (3-hydroxypropionate) according to claim 10, wherein the alkyl poly(3-hydroxypropionate) having a number average molecular weight of 300 g / mol or more and 3,000 g / mol or less has an acid value of 1.0 meq / Kg or more and 333.0 meq / Kg or less, The alkyl poly(3-hydroxypropionate) having a number average molecular weight of greater than 3,000 g / mol and 8,000 g / mol or less has an acid value of 300.0 meq / Kg or less, and The alkyl poly(3-hydroxypropionate) having a number average molecular weight of greater than 8,000 g / mol and 30,000 g / mol or less has an acid value of 150.0 meq / Kg or less.

12. The alkyl poly (3-hydroxypropionate) according to claim 10, The alkyl poly (3-hydroxypropionate) has a vinyl content at the terminal of 30 mol% or less.

13. An alkyl poly (3-hydroxypropionate) composition comprising: an alkyl poly(3-hydroxypropionate) represented by the following Chemical Formula 1, and Alcohols having 2 to 20 carbon atoms: [Chemical formula 1] Wherein in Chemical Formula 1, R is C n H 2n+1 A linear or branched alkyl group represented by (wherein n is an integer from 2 to 20), and m is an integer of 10 or more.

14. The alkyl poly (3-hydroxypropionate) composition according to claim 13, wherein the alkyl poly(3-hydroxypropionate) having a number average molecular weight of 300 g / mol or more and 3,000 g / mol or less has an acid value of 1.0 meq / Kg or more and 333.0 meq / Kg or less, The alkyl poly(3-hydroxypropionate) having a number average molecular weight of greater than 3,000 g / mol and 8,000 g / mol or less has an acid value of 300.0 meq / Kg or less, and The alkyl poly(3-hydroxypropionate) having a number average molecular weight of greater than 8,000 g / mol and 30,000 g / mol or less has an acid value of 150.0 meq / Kg or less.

15. The alkyl poly (3-hydroxypropionate) composition according to claim 13, The alkyl poly (3-hydroxypropionate) has a vinyl content at the terminal of 30 mol% or less.

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