Method for producing alkyl poly(3-hydroxypropionate), alkyl poly(3-hydroxypropionate) and composition containing the same

Abstract

The present invention provides a method for producing alkyl poly(3-hydroxypropionate), which includes a step of producing alkyl poly(3-hydroxypropionate) by condensation polymerization of alkyl-3-hydroxypropionate, wherein the alkyl-3-hydroxypropionate has 2 to 20 carbon atoms, as well as alkyl poly(3-hydroxypropionate) and a composition thereof.

Description

[Technical Field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0183172 dated December 23, 2022, and all contents disclosed in the documents of that Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a method for producing alkyl poly(3-hydroxypropionate), alkyl poly(3-hydroxypropionate), and compositions containing the same. [Background technology]

[0003] Poly(3-hydroxypropionate) is a biodegradable polymer that is not only durable but also has excellent mechanical properties, and is therefore attracting attention as an eco-friendly material.

[0004] Poly(3-hydroxypropionate) is produced by condensation polymerization of the monomer 3-hydroxypropionic acid (3-HP), and the production of 3-hydroxypropionic acid by microbial fermentation has been gaining attention as an environmentally friendly bioprocess.

[0005] However, when producing 3-hydroxypropionic acid by microbial fermentation, since by-products other than 3-hydroxypropionic acid are also produced during the fermentation process, various processes are required to separate and purify 3-hydroxypropionic acid from the fermentation broth. In particular, 3-hydroxypropionic acid is highly hydrophilic and has high solubility and reactivity in water, making it difficult to separate and purify.

[0006] As an example of recovering 3-hydroxypropionic acid, 3-hydroxypropionic acid can be converted to alkyl-3-hydroxypropionate and purified, but this requires additional steps such as removing the alkyl group. Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention provides a method for producing alkyl poly(3-hydroxypropionate) by condensation polymerization of alkyl 3-hydroxypropionate, the alkyl poly(3-hydroxypropionate) produced thereby, and a composition containing the same. [Means for solving the problem]

[0008] According to one embodiment of the present invention, there is provided a method for preparing alkyl poly(3-hydroxypropionate), comprising the step of condensation polymerizing alkyl-3-hydroxypropionate to prepare alkyl poly(3-hydroxypropionate) represented by the following Chemical Formula 1, wherein the alkyl-3-hydroxypropionate has 2 to 20 alkyl carbon atoms:

[0009] According to another embodiment of the present invention, there is provided an alkyl poly(3-hydroxypropionate) represented by the following Chemical Formula 1:

[0010] According to another embodiment of the present invention, there is provided an alkyl poly(3-hydroxypropionate) composition comprising an alkyl poly(3-hydroxypropionate) represented by the following Chemical Formula 1 and an alcohol having 2 to 20 carbon atoms:

[0011] Hereinafter, a method for producing alkyl poly(3-hydroxypropionate), alkyl poly(3-hydroxypropionate), and a composition containing the same according to specific embodiments of the present invention will be described in more detail.

[0012] Furthermore, unless the steps constituting the manufacturing method described herein are explicitly stated to be sequential or continuous, or there is another special class, it should not be construed as being limited to the order in which one step and another step constituting a manufacturing method are described in the specification. Therefore, the order of the steps constituting the manufacturing method may be changed within a range that can be easily understood by a person skilled in the art, and in this case, the accompanying changes that are obvious to a person skilled in the art are included in the scope of the present invention.

[0013] Unless otherwise specified throughout this specification, the terms "comprise" or "contain" refer to the inclusion of a certain component (or ingredient) without any particular limitation, and should not be interpreted as excluding the addition of other components (or ingredients).

[0014] Unless otherwise specified herein, the weight-average molecular weight and number-average molecular weight of alkyl poly(3-hydroxypropionate) 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 100 μL is injected into the GPC. GPC analysis is performed at 40°C. The moving bed of the GPC is chloroform, with a flow rate of 1.0 mL / min. Two Agilent Mixed-B columns are connected in series, and an RI detector is used. Mw values ​​are derived using a calibration curve generated using polystyrene standard specimens. Twelve types of polystyrene standard specimens were used, 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.

[0015] According to one embodiment of the present invention, there is provided a method for preparing alkyl poly(3-hydroxypropionate), comprising the step of condensation polymerizing alkyl-3-hydroxypropionate to prepare alkyl poly(3-hydroxypropionate) represented by the following Chemical Formula 1, wherein the alkyl-3-hydroxypropionate has 2 to 20 alkyl carbon atoms:

[0016] [ka] In the above formula 1, R is C n H 2n+1 (n is an integer of 2 to 20), m is an integer of 10 or greater.

[0017] The present inventors have discovered that when alkyl-3-hydroxypropionate is condensed to produce alkyl poly(3-hydroxypropionate), an alcohol having a boiling point lower than that of water is produced as a condensation polymerization by-product, and the by-product can be efficiently removed. Furthermore, the carboxyl group (-COOH) of the finally produced alkyl poly(3-hydroxypropionate) is capped with an alkyl group, resulting in a low acid value of the polymer, a low content of vinyl groups among the terminal groups, and an excellent final recovery yield. Based on this discovery, the present invention has been completed.

[0018] In the method for producing alkyl poly(3-hydroxypropionate) according to the embodiment, the alkyl-3-hydroxypropionate is polycondensed to produce the alkyl poly(3-hydroxypropionate) represented by Chemical Formula 1.

[0019] When alkyl-3-hydroxypropionate is condensed to produce alkyl poly(3-hydroxypropionate), alcohol is generated as a condensation polymerization by-product. However, since the boiling point of this alcohol is lower than that of water, it can be efficiently removed even at low temperatures. Furthermore, the amount of the final by-product is small, so the water removal process involved in the conventional production of poly(3-hydroxypropionate) can be omitted.

[0020] In addition, the alkyl poly(3-hydroxypropionate) may have a lower acid value because the terminal carboxylic acid group is replaced with an alkyl ester, resulting in capping of the terminal carboxylic group. The lower acid value of the alkyl poly(3-hydroxypropionate) may improve the storage stability of the polymer and reduce the likelihood of side reactions. Furthermore, while conventional polymers require the addition of additives to reduce the acid value, the method of the present invention can reduce the acid value without the addition of additional additives, thereby reducing the generation of by-products.

[0021] Meanwhile, the acid value of the alkyl poly(3-hydroxypropionate) may show different trends depending on the number average molecular weight. For example, when the number average molecular weight of the alkyl poly(3-hydroxypropionate) exceeds 3,000 g / mol, the acid value may increase as the number average molecular weight decreases.

[0022] However, the alkyl poly(3-hydroxypropionate) produced by the method according to one embodiment may have a number-average molecular weight of more than 3,000 g / mol but a low acid value of 300.0 meq / kg or less. For example, the alkyl poly(3-hydroxypropionate) having a number-average molecular weight of more than 3,000 g / mol but not more than 8,000 g / mol may have an acid value of 300.0 meq / kg or less, 1.0 meq / kg or more but not more than 290.0 meq / kg, 10.0 meq / kg or more, 20.0 meq / kg or more, 30.0 meq / kg or more, or 50.0 meq / kg or more, or 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. Furthermore, the alkyl poly(3-hydroxypropionate) having a number average molecular weight of more than 8,000 g / mol and not more than 30,000 g / mol may have an acid value of not more than 150.0 meq / kg, or not less than 1.0 meq / kg and not more than 140.0 meq / kg, or may have an acid value of not less than 10.0 meq / kg, not less than 20.0 meq / kg, or not more than 145.0 meq / kg, not more than 140.0 meq / kg, not more than 135.0 meq / kg, or not more than 130.0 meq / kg.

[0023] On the other hand, 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 have an acid value of 1.0 meq / kg or more and 333.0 meq / kg or less, or 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.

[0024] The alkyl poly(3-hydroxypropionate) may be produced by polycondensing the alkyl 3-hydroxypropionate, and the terminal vinyl group content of the alkyl poly(3-hydroxypropionate) may be 40 mol% or less. For example, the terminal vinyl group content of the alkyl poly(3-hydroxypropionate) may 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.

[0025] The alkyl poly(3-hydroxypropionate) may have terminal groups such as hydroxy, carboxy, or vinyl. However, since the alkyl poly(3-hydroxypropionate) is produced by condensation polymerization of the alkyl 3-hydroxypropionate, the presence of vinyl groups at the terminals is unlikely. Vinyl groups are generated as a side reaction during the polymerization of 3-hydroxypropionic acid to poly(3-hydroxypropionic acid). This can disrupt the equivalent ratio of functional groups (hydroxy and carboxy) during condensation polymerization, which is crucial, thereby hindering the reaction rate and making it difficult to obtain a high molecular weight polymer. Furthermore, the presence of vinyl groups in the alkyl poly(3-hydroxypropionate) can prevent proper chain extension of the alkyl poly(3-hydroxypropionate) through further modification. Therefore, the poly(3-hydroxypropionate) has the advantage of having fewer vinyl groups at the terminals, fundamentally eliminating these drawbacks.

[0026] The end group content of the poly(3-hydroxypropionic acid) was measured using a Buker 500 MHz NMR model instrument. 1 The ratio of vinyl groups to all end groups can be calculated by H-NMR measurement. For example, the polymer is dissolved in d-CDCl3 at a concentration of 8 mg / ml and the measurement is performed, and the ratio can be calculated using the following equation 1.

number

[0027] The alkyl-3-hydroxypropionate may have 2 to 20, 2 to 10, 2 to 8, or 2 to 6 carbon atoms in the alkyl, and may be, for example, ethyl, n-propyl, isopropyl, n-butyl, or tert-butyl.

[0028] The alkyl poly(3-hydroxypropionate) may be represented by the following Chemical Formula 1: [ka]

[0029] The R is an alkyl group capping the carboxy group of poly(3-hydroxypropionate), and may be derived from the alkyl of alkyl-3-hydroxypropionate. For example, the R is C n H 2n+1 a linear or branched alkyl group represented by the formula (n is an integer of 2 to 20), C n H 2n+1 a linear or branched alkyl group represented by the formula (n is an integer of 2 to 10), or C n H 2n+1 (n is an integer of 2 to 6), specifically, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, or a tert-butyl group.

[0030] The m represents the number of repeating structures, and may be, for example, an integer of 10 or more or an integer of 10 to 600.

[0031] The alkyl poly(3-hydroxypropionate) may have a weight-average molecular weight of 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, the crystallinity may be low and the product may not exist in a solid state, and the product may be easily crushed and have low strength. If the weight-average molecular weight is too high, the viscosity may be high and processing may be difficult.

[0032] The alkyl poly(3-hydroxypropionate) may have a number average molecular weight of 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, the crystallinity may be low and the product may not exist in a solid state, resulting in easy crushing and low strength. If the number average molecular weight is too high, the viscosity may be high, making processing difficult.

[0033] The alkyl poly(3-hydroxypropionate) may have a number average molecular weight or 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 invention may 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.

[0034] The alkyl poly(3-hydroxypropionate) produced by the method according to the embodiment can be produced by polycondensation of alkyl-3-hydroxypropionate. Specifically, polycondensation of alkyl-3-hydroxypropionate can be carried out at a temperature of 50° C. to 250° C. for 6 hours to 30 hours.

[0035] For example, the condensation polymerization may be carried out at a temperature of 50°C or higher, or 70°C or higher, or 90°C or higher, or 110°C or higher and 250°C or lower, or 230°C or lower, or 200°C or lower, for 6 hours or higher, or 8 hours or higher, or 10 hours or higher and 30 hours or lower, or 28 hours or lower, or 26 hours or lower. When carried out under these conditions, the alkyl poly(3-hydroxypropionate) having the physical properties and weight average molecular weight in the optimum range desired in the present invention can be produced in an excellent yield.

[0036] The polycondensation may be carried out in the presence of one or more catalysts selected from the group consisting of sulfonic acid catalysts, metal oxide catalysts, metal chloride catalysts, and metal alkoxide catalysts.

[0037] Examples of the sulfonic acid catalyst include, but are not limited to, 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, and the like. toluenesulfonic acid, 3,5-diamino-2,4,6-trimethylbenzenesulfonic acid, 2,4-dinitrobenzenesulfonic acid, p-chlorobenzenesulfonic acid, 2,5-dichlorobenzenesulfonic acid, hydroxynitrobenzenesulfonic acid, aminotoluenesulfonic acid, p-phenolsulfonic acid, aminophenolsulfonic acid, cumenesulfonic acid, xylenesulfonic acid, o-cresolsulfonic acid, m-cresolsulfonic acid, p-cresolsulfonic acid, p-toluenesulfonic acid (p-TSA ), methanesulfonic acid (m-SA), trifluoromethanesulfonic acid, nanofluorobutane-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, and the like.

[0038] The metal oxide may be, but is not limited to, germanium dioxide, zinc oxide, tin oxide, antimony trioxide, iron trioxide, aluminum trioxide, silicon dioxide, titanium dioxide, and the like.

[0039] The metal alkoxide may be, but is not limited to, titanium butoxide, titanium isopropoxide, aluminum isopropoxide, yttrium isopropoxide, germanium ethoxide, silicon ethoxide, tin octoate, or the like.

[0040] The metal chloride may be, 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, etc.

[0041] The catalyst may be used in an amount of 0.001 mol% to 10 mol% based on the alkyl-3-hydroxypropionate. For example, the catalyst may be used in an amount of 0.010 mol% or more, 0.050 mol% or more, 0.10 mol% or more, or 0.20 mol% or more based on the alkyl-3-hydroxypropionate, or in an amount of 10 mol% or less, 5 mol% or less, 3 mol% or less, or 1 mol% or less. If the catalyst is used in an excessively small amount, the polymerization activity may be insufficient. If the catalyst is used in an excessively large amount, the residual catalyst amount may increase, resulting in depolymerization such as transesterification, which may lead to polymer decomposition or a decrease in molecular weight.

[0042] The method according to the embodiment may include the steps of melt-polymerizing alkyl-3-hydroxypropionate to produce an alkyl-3-hydroxypropionic acid oligomer (Step 1); and further polymerizing the alkyl-3-hydroxypropionic acid oligomer to produce alkyl poly(3-hydroxypropionate) (Step 2).

[0043] The melt polymerization refers to the reaction of alkyl-3-hydroxypropionic acid (a reactant) and alkyl-3-hydroxypropionic acid oligomer (a product) in a liquid state. To achieve this, the reaction temperature in Step 1 is controlled to 40°C to 120°C. While not theoretically limited, the melt polymerization conditions described above suppress the formation of cyclic oligomers during the polymerization of alkyl-3-hydroxypropionic acid. Preferably, the reaction temperature in Step 1 is 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.

[0044] Step 1 can be carried out at a pressure of 5 mbar to 200 mbar. When Step 1 is carried out at such low pressures, polymerization of the alkyl-3-hydroxypropionic acid can be promoted. More preferably, Step 1 can be carried out at a pressure of 6 mbar or more, or 7 mbar or more, but not more than 190 mbar, 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.

[0045] The reaction time of step 1 can be appropriately adjusted taking into consideration the molecular weight and yield of the alkyl-3-hydroxypropionic acid oligomer to be produced, and is preferably 1 to 5 hours. Within this 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.

[0046] Furthermore, the catalyst may be added in a predetermined amount during the reaction in step 1. The catalyst has the effect of promoting polymerization of alkyl-3-hydroxypropionic acid and suppressing the formation of cyclic oligomers during the polymerization of alkyl-3-hydroxypropionic acid.

[0047] Meanwhile, for the melt polymerization in step 1, if necessary, a step of drying the alkyl-3-hydroxypropionic acid may be performed before performing step 1. The drying can remove moisture present in the alkyl-3-hydroxypropionic acid. Here, the drying temperature is preferably 40 to 95°C, the drying pressure is preferably 10 mbar to atmospheric pressure, and the drying time is preferably 1 to 10 hours.

[0048] In the step 2, the alkyl-3-hydroxypropionic acid oligomer can be further polymerized to produce alkyl poly(3-hydroxypropionate).

[0049] Unlike Step 1, since the reactant is an oligomer, the polymerization temperature may be higher and the pressure may be lower than those of 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.

[0050] The pressure in step 2 is 1 mbar or less, more preferably 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.

[0051] The reaction time of step 2 can be appropriately adjusted taking into consideration the molecular weight and yield of the alkyl poly(3-hydroxypropionate) produced, and is preferably 6 hours or more, 8 hours or more, or 10 hours or more, and 30 hours or less, 28 hours or less, or 26 hours or less. Within this 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.

[0052] Meanwhile, since step 2 is performed after step 1, the catalyst added in step 1 also participates in the reaction in step 2. Therefore, the catalyst described in step 1 can also be used in step 2.

[0053] According to another embodiment of the present invention, there is provided an alkyl poly(3-hydroxypropionate) represented by the following Chemical Formula 1: [ka] In the above formula 1, R is C n H 2n+1 (n is an integer of 2 to 20), m is an integer of 10 or greater.

[0054] The alkyl poly(3-hydroxypropionate) may be produced by the method for producing alkyl poly(3-hydroxypropionate) according to the embodiment.

[0055] The acid value, vinyl group content among the terminal groups, weight average molecular weight and number average molecular weight of the alkyl poly(3-hydroxypropionate) are as described above.

[0056] According to another embodiment of the present invention, there is provided an alkyl poly(3-hydroxypropionate) composition comprising an alkyl poly(3-hydroxypropionate) represented by Chemical Formula 1 and an alcohol having 2 to 20 carbon atoms.

[0057] The composition may be produced by the method for producing alkyl poly(3-hydroxypropionate) according to the embodiment.

[0058] In this method, alkyl-3-hydroxypropionate is condensed to produce poly(3-hydroxypropionate), and the alcohol having 2 to 20 carbon atoms can be produced as a by-product. The alcohol has a lower boiling point than water and can be efficiently removed at low temperatures. Furthermore, the amount of by-products generated is small, making it possible to omit the water removal process required in the conventional production of poly(3-hydroxypropionate).

[0059] The alcohol may have 2 to 20, 2 to 10, 2 to 8, or 2 to 6 carbon atoms, for example, the alcohol may be ethanol, n-propanol, isopropanol, n-butanol, or tert-butanol. [Effects of the Invention]

[0060] The present invention provides a method for producing alkyl poly(3-hydroxypropionate) by condensation polymerization of alkyl-3-hydroxypropionate, which allows by-products such as alcohol to be efficiently removed, and the resulting polymer has a low acid value and little vinyl group formation due to side reactions, and can provide alkyl poly(3-hydroxypropionate) and a composition containing the same. DETAILED DESCRIPTION OF THE INVENTION

[0061] The present invention will be described in more detail in the following examples, but the following examples are merely illustrative of the present invention and are not intended to limit the scope of the present invention. Experimental Example 1

[0062] 15 g of dehydrated ethyl 3-hydroxypropionate was placed in a reactor, and 0.4 mol % of octyltriamine (based on the ethyl 3-hydroxypropionic acid) was added as a catalyst. The temperature and pressure inside the reactor were maintained at 90°C and 10 torr, respectively, and the reaction was continued for 2 hours to produce ethyl 3-hydroxypropionate oligomer. The temperature and pressure inside the reactor were then adjusted to 90°C and 0.2 torr, respectively, and the reaction was continued for 24 hours to produce ethyl poly(3-hydroxypropionate). Experimental Example 2

[0063] 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. Experimental Example 3

[0064] Ethyl poly(3-hydroxypropionate) was prepared in the same manner as in Experimental Example 1, except that tin chloride (SnCl2) was used instead of octyltriamine.

[0065] <Evaluation> 1. Gas Chromatography (GC) Measurement The reaction products of Experimental Examples 1 to 3 were analyzed by gas chromatography (GC) to determine the contents of by-products produced other than the final product ethyl poly(3-hydroxypropionate), such as ethanol, ethyl 3-hydroxypropionate, dimer, and other by-products. The results are shown in Table 1 below. [Table 1]

[0066] According to Table 1, in Experimental Examples 2 and 3, the starting material ethyl-3-hydroxypropionate was measured at a low level of 64.5 wt % or less, whereas in Experimental Example 1, the ethyl-3-hydroxypropionate was measured at 99.2 wt %, confirming that the polycondensation reactivity was lower than in Experimental Examples 2 and 3.

[0067] Example 1 15 g of dehydrated ethyl 3-hydroxypropionate was placed in a reactor, and 19.7 mg of m-SA (methanesulfonic acid) was added as a catalyst at 0.2 mol% relative to the ethyl 3-hydroxypropionate. The temperature and pressure inside the reactor were maintained at 90°C and 10 torr, respectively, and the reaction was continued for 2 hours to produce ethyl 3-hydroxypropionate oligomer. The temperature and pressure inside the reactor were then adjusted to 90°C and 0.2 torr, respectively, and the reaction was continued for 24 hours to produce ethyl poly(3-hydroxypropionate).

[0068] Example 2 15 g of dehydrated tert-butyl-3-hydroxypropionate was placed in a reactor, and 19.7 mg of m-SA (methanesulfonic acid) was added as a catalyst at 0.2 mol% relative to the tert-butyl-3-hydroxypropionate. The temperature and pressure inside the reactor were maintained at 90°C and 10 torr, respectively, and the reaction was continued for 2 hours to produce ethyl-3-hydroxypropionate oligomer. The temperature and pressure inside the reactor were then adjusted to 90°C and 0.2 torr, respectively, and the reaction was continued for 24 hours to produce tert-butyl poly(3-hydroxypropionate).

[0069] Example 3 Tert-butyl poly(3-hydroxypropionate) was produced 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.

[0070] Example 4 Tert-butyl poly(3-hydroxypropionate) was produced 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).

[0071] Example 5 Tert-butyl poly(3-hydroxypropionate) was produced 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).

[0072] Example 6 Tert-butyl poly(3-hydroxypropionate) was produced in the same manner as in Example 5, except that the reaction temperature was controlled at 120°C in both cases.

[0073] Example 7 Tert-butyl poly(3-hydroxypropionate) was produced in the same manner as in Example 5, except that the reaction temperature was controlled at 140°C in both cases.

[0074] Example 8 Tert-butyl poly(3-hydroxypropionate) was produced in the same manner as in Example 5, except that the reaction temperature was controlled at 160°C in both cases.

[0075] Example 9 Tert-butyl poly(3-hydroxypropionate) was produced in the same manner as in Example 5, except that the reaction temperature was controlled at 180°C in both cases.

[0076] Example 10 15 g of dehydrated n-butyl-3-hydroxypropionate was placed in a reactor, and 126.6 mg of p-TSA (0.4 mol % based on n-butyl-3-hydroxypropionate) was added as a catalyst. The temperature and pressure inside the reactor were maintained at 90°C and 10 torr, respectively, and the reaction was continued for 2 hours to produce n-butyl-3-hydroxypropionate oligomer. The temperature and pressure inside the reactor were then adjusted to 90°C and 0.2 torr, respectively, and the reaction was continued for 24 hours to produce n-butyl poly(3-hydroxypropionate).

[0077] Example 11 15 g of dehydrated n-butyl-3-hydroxypropionate was placed in a reactor, and titanium butoxide (Ti(BuO)4) was added as a catalyst at 0.4 mol% relative to the n-butyl-3-hydroxypropionate. The temperature and pressure inside the reactor were maintained at 90°C and 10 torr, respectively, and the reaction was continued for 2 hours to produce n-butyl-3-hydroxypropionate oligomer. The temperature and pressure inside the reactor were then adjusted to 90°C and 0.2 torr, respectively, and the reaction was continued for 24 hours to produce n-butyl poly(3-hydroxypropionate).

[0078] Example 12 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 changed to 120°C and 0.2 torr, and the reaction time was controlled to 8 hours.

[0079] Example 13 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 changed to 140°C and 0.2 torr, and the reaction time was controlled to 8 hours.

[0080] Example 14 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 changed to 160°C and 0.2 torr, and the reaction was carried out for 18 hours.

[0081] Example 15 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 changed to 180°C and 0.2 torr, and the reaction time was controlled to 8 hours.

[0082] Comparative Example 1 15 g of dehydrated 3-hydroxypropionic acid was placed in a reactor, and 63.3 mg of p-TSA (0.2 mol % based on the 3-hydroxypropionic acid) was added as a catalyst. The temperature and pressure inside the reactor were maintained at 90°C and 10 torr, respectively, and the reaction was continued for 2 hours to produce 3-hydroxypropionate oligomer. The temperature and pressure inside the reactor were then adjusted to 90°C and 0.2 torr, respectively, and the reaction was continued for 24 hours to produce poly(3-hydroxypropionate).

[0083] Comparative Example 2 Poly(3-hydroxypropionate) was produced 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.

[0084] Comparative Example 3 15 g of dehydrated methyl 3-hydroxypropionate was placed in a reactor, and 19.7 mg of m-SA (0.2 mol % based on the methyl 3-hydroxypropionate) was added as a catalyst. The temperature and pressure inside the reactor were maintained at 90°C and 10 torr, respectively, and the reaction was continued for 2 hours to produce methyl 3-hydroxypropionate oligomer. The temperature and pressure inside the reactor were then adjusted to 90°C and 0.2 torr, respectively, and the reaction was continued for 24 hours to produce methyl poly(3-hydroxypropionate).

[0085] <Evaluation> 1. Measurement by Gel Permeation Chromatography For the polymers produced in the above Examples and Comparative Examples, the weight-average molecular weight, number-average molecular weight, and polydispersity index were measured by gel permeation chromatography (GPC: gel permeation chromatography, Waters Alliance e2695), and the results are shown in Table 2 below.

[0086] <GPC Analysis Conditions> After dissolving the product in chloroform to a concentration of 1 mg / ml, 100 μl was injected into GPC, and GPC analysis was performed at 40°C. At this time, chloroform was used for the mobile phase of GPC and flowed in at a flow rate of 1.0 mL / min. Two Agilent Mixed-B columns were connected in series and used, and an RI Detector was used as the detector. The Mw value was derived using a calibration curve formed using polystyrene standard specimens. The weight-average molecular weights of the polystyrene standard specimens were 12 kinds, namely 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.

[0087] 2. Evaluation of Yield For the polymers produced in the above Examples and Comparative Examples, the yield was calculated using the following Formulas 2 and 3, and the results are shown in Table 2 below. <Formula 2> Theoretical value = amount of alkyl-3-hydroxypropionate input (g) × (polymer molecular weight / alkyl-3-hydroxypropionate molecular weight) <Formula 3> Yield (%) = amount of finally produced polymer obtained / theoretical value × 100

[0088] 3. Analysis of Vinyl Group Content of Terminal Groups The polymers prepared in Examples 1 to 3 and 11 and Comparative Examples 1 to 3 were analyzed using a Buker 500 MHz NMR model instrument. 1 The ratio of vinyl groups to all end groups was calculated by H-NMR measurement. Specifically, each polymer was dissolved in d-CDCl3 at a concentration of 8 mg / ml, and the ratio was calculated using the following equation 1. The results are shown in Table 3.

number

[0089] In the above formula 1, a is 6.3 ppm of C=C 1 is the area value of H, b is 3.8 ppm of HO-CH2- 2 is the area value of H. 4. Measurement of polymer acid value The acid values ​​of the polymers prepared in Examples 1 to 3 and 11 and Comparative Examples 1 to 3 were measured according to ASTM D4662, and the results are shown in Table 4 below.

[0090] Specifically, a Mettler Toledo T5 instrument was used with a DGi 116-solvent electrode, and 0.02N potassium methoxide solution was used as the titrant, and the titration point was analyzed. [Table 2] [Table 3] [Table 4]

[0091] Referring to Table 2 above, it was confirmed that the polymers of the examples prepared using ethyl-3-hydroxypropionate, tert-butyl-3-hydroxypropionate, or n-butyl-3-hydroxypropionate had significantly higher yields than the polymer of Comparative Example 3 prepared using methyl-3-hydroxypropionate.

[0092] Furthermore, referring to Table 3, it was confirmed that the Examples in which polymers were prepared using alkyl-3-hydroxypropionate did not contain vinyl groups among the terminal groups of the polymers, unlike Comparative Examples 1 and 2 in which polymers were prepared using 3-hydroxypropionic acid.

[0093] Furthermore, referring to Table 4, it was confirmed that the acid value of a polymer is affected by the number average molecular weight, and that although Comparative Example 1 and Example 3 have similar number average molecular weights, the acid value of Example 3 is significantly lower than the acid value of Comparative Example 1. It was also confirmed that although Example 1 and Comparative Example 3 have similar number average molecular weights, the acid value of Example 1 is lower than the acid value of Comparative Example 3.

Claims

1. Polycondensation of alkyl-3-hydroxypropionate to prepare alkyl poly(3-hydroxypropionate) represented by the following Chemical Formula 1: The alkyl-3-hydroxypropionate has an alkyl group having 2 to 20 carbon atoms. 【Chemical 1】 In the above formula 1, R is C ｎ H ２ｎ＋１ (n is an integer of 2 to 20), m is an integer of 10 or more.

2. 2. The method for producing alkyl poly(3-hydroxypropionate) according to claim 1, wherein the condensation polymerization is carried out in the presence of one or more catalysts selected from the group consisting of sulfonic acid catalysts, metal oxide catalysts, metal chloride catalysts, and metal alkoxide catalysts.

3. 3. The method for producing 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-hydroxypropionate.

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

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

6. 2. The method for producing 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. 2. The method for producing 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 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 more than 3,000 g / mol and not more than 8,000 g / mol has an acid value of not more than 300.0 meq / kg; The method for producing alkyl poly(3-hydroxypropionate) according to claim 1, wherein the alkyl poly(3-hydroxypropionate) having a number average molecular weight of more than 8,000 g / mol and not more than 30,000 g / mol has an acid value of not more than 150.0 meq / kg.

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

10. Alkyl poly(3-hydroxypropionate) represented by the following chemical formula 1. 【Chemistry 2】 In the above formula 1, R is C ｎ H ２ｎ＋１ (n is an integer of 2 to 20), m is an integer of 10 or more.

11. 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 more than 3,000 g / mol and not more than 8,000 g / mol has an acid value of not more than 300.0 meq / kg; The alkyl poly(3-hydroxypropionate) according to claim 10, wherein the alkyl poly(3-hydroxypropionate) has a number average molecular weight of more than 8,000 g / mol and not more than 30,000 g / mol and an acid value of not more than 150.0 meq / kg.

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

13. Alkyl poly(3-hydroxypropionate) represented by the following chemical formula 1, and containing an alcohol having 2 to 20 carbon atoms, Alkyl poly(3-hydroxypropionate) compositions. 【Chemistry 3】 In the above formula 1, R is C ｎ H ２ｎ＋１ (n is an integer of 2 to 20), m is an integer of 10 or more.

14. 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 more than 3,000 g / mol and not more than 8,000 g / mol has an acid value of not more than 300.0 meq / kg; 14. The alkyl poly(3-hydroxypropionate) composition according to claim 13, wherein the alkyl poly(3-hydroxypropionate) having a number average molecular weight of more than 8,000 g / mol and not more than 30,000 g / mol has an acid value of not more than 150.0 meq / kg.

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

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