Molded article and preform

Abstract

To provide a molded article that reduces environmental burden and has physical properties including mechanical performance comparable to those of conventional molded articles produced from fossil fuel-derived materials, as well as a preform for use in manufacturing the molded article.SOLUTION: According to the present disclosure, the molded article is a molded article made of a polyester comprising a diol unit and a dicarboxylic acid unit, characterized in that the diol unit includes ethylene glycol derived from at least one gas selected from the group consisting of carbon monoxide and carbon dioxide.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to molded articles and preforms. [Background technology]

[0002] Polyesters are widely used in various industrial applications due to their excellent mechanical properties, chemical stability, heat resistance, transparency, etc., and their low cost. Polyesters are obtained by polycondensation of diol units and dicarboxylic acid units. For example, polyethylene terephthalate is produced by esterifying ethylene glycol and terephthalic acid as raw materials, followed by polycondensation. These raw materials are produced from petroleum, a fossil fuel. For example, ethylene glycol is industrially produced from ethylene, and terephthalic acid is industrially produced from xylene.

[0003] In recent years, with growing calls for the creation of a recycling-oriented society, there has been a desire to move away from fossil fuels in the materials field, just as there has been in the energy field. Therefore, the production of polyester from raw materials other than fossil fuels, such as biomass, has been considered. Biomass is an organic compound formed by photosynthesis from carbon dioxide and water, and by utilizing it, it can be converted back into carbon dioxide and water, making it a so-called carbon-neutral renewable energy source. Recently, the practical application of biomass plastics made from biomass has progressed rapidly, and attempts have been made to produce polyester, a general-purpose polymer material, from these biomass raw materials (e.g., Patent Documents 1 and 2). Using polyester produced from biomass-derived raw materials (biomass polyester) instead of polyester produced from fossil fuel-derived raw materials can reduce the amount of fossil fuel used and the environmental impact.

[0004] Bioethanol, which is used to produce biomass polyester, is generally produced by sugar fermentation from edible raw materials such as corn. However, mass production of bioethanol from edible raw materials for the purpose of producing biomass polyester can lead to problems such as a rise in food prices, as limited agricultural land is used for non-food production. To solve this problem, ethanol has been produced by microbial fermentation using carbon monoxide present in exhaust gases emitted from steel mills and factories as a raw material (for example, Patent Document 3). Ethylene glycol has also been produced by electrolyzing carbon dioxide present in exhaust gases emitted from steel mills and factories (for example, Patent Document 4). Furthermore, the production of polyesters from these compounds has also been considered. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Special Publication No. 2011-527348 [Patent Document 2] Special Publication No. 2012-519748 [Patent Document 3] Special Publication No. 2011-512869 [Patent Document 4] Japanese Patent Application Publication No. 2018-123390 Summary of the Invention [Problem to be solved by the invention]

[0006] Molded articles such as containers have been produced from polyesters produced from fossil fuel-derived raw materials or biomass-derived raw materials for some time. However, it was unclear whether molded articles produced from polyesters produced using ethanol, which is made from carbon monoxide gas, or ethylene glycol, which is made from carbon dioxide gas, would exhibit the same mechanical properties as conventional molded articles.

[0007] Therefore, an object of the present disclosure is to provide a molded article that can reduce the environmental load and is comparable in terms of physical properties such as mechanical properties to conventional molded articles produced from raw materials derived from fossil fuels. Another object of the present disclosure is to provide a preform used in producing the molded article. [Means for solving the problem]

[0008] The present inventors have found that molded articles produced using ethylene glycol, which is made from carbon monoxide gas or carbon dioxide gas as raw materials, are comparable in terms of physical properties, such as mechanical properties, to conventional molded articles produced from raw materials derived from fossil fuels. The present disclosure was completed based on this finding and through further investigation.

[0009] The present disclosure is solved by the following embodiments. <1> A molded article of a polyester comprising diol units and dicarboxylic acid units, The molded article, wherein the diol unit comprises ethylene glycol obtained from at least one gas selected from the group consisting of carbon monoxide and carbon dioxide. <2> The carbon dioxide molecule content is 9.2 x 10 17 pcs / g or more 3.0×10 18 pieces / g or less, <1> The molded article according to claim 1. <3> The Kjeldahl nitrogen content is 18 μg / g or less. <1> or <2> The molded article according to claim 1. <4> The dicarboxylic acid unit includes at least one selected from the group consisting of terephthalic acid derived from a fossil fuel, terephthalic acid derived from biomass, and terephthalic acid derived from carbon dioxide gas. <1> ~ <3> 1. The molded article according to any one of the preceding items. <5> The molded article is a container. <1> ~ <4> 1. The molded article according to any one of the preceding items. <6> <5> A preform used in the production of the molded article described in 1. [Effects of the Invention]

[0010] The present disclosure can provide molded articles that can reduce the environmental load and are comparable in terms of physical properties such as mechanical properties to conventional molded articles produced from raw materials derived from fossil fuels. The present disclosure can also provide a preform used in producing the molded article. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a front view showing a container, which is one embodiment of a molded product according to the present disclosure. [Figure 2] 1 is a schematic half-sectional view showing one embodiment of a preform according to the present disclosure. [Figure 3] FIG. 1 is a perspective view showing a spoon, which is one embodiment of a molded product according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0012] [polyester] The polyester constituting the molded article according to the present disclosure is composed of diol units and dicarboxylic acid units, and is obtained by a polycondensation reaction using ethylene glycol as the diol units and dicarboxylic acid as the dicarboxylic acid units, which are derived from at least one gas selected from the group consisting of carbon monoxide and carbon dioxide. Ethylene glycol made from carbon monoxide gas and ethylene glycol made from carbon dioxide gas will be described below.

[0013] [Ethylene glycol made from carbon monoxide gas] Ethylene glycol using carbon monoxide gas as a raw material can be produced from ethanol using carbon monoxide gas as a raw material. For example, ethylene glycol using carbon monoxide gas as a raw material can be obtained by, for example, producing ethanol using carbon monoxide gas as a raw material and then converting it into ethylene oxide using a conventionally known method.

[0014] <Microbial fermentation> Ethanol, which is made from carbon monoxide gas, can be obtained by microbial fermentation.

[0015] Microbial fermentation is carried out, for example, in a fermenter filled with a culture solution containing water and microorganisms. A feed gas containing carbon monoxide gas is supplied into the fermenter, and the carbon monoxide gas is converted into ethanol inside the fermenter. The feed gas may contain carbon dioxide, nitrogen, oxygen, etc. in addition to carbon monoxide.

[0016] The fermenter is preferably a continuous fermentation apparatus, and may be any of agitation type, airlift type, bubble column type, loop type, open bond type, and photobio type. The raw material gas and the culture solution may be continuously supplied to the fermenter, but it is not necessary to supply the raw material gas and the culture solution simultaneously, and the raw material gas may be supplied to a fermenter to which the culture solution has been previously supplied. The raw material gas is generally blown into the fermenter through a sparger or the like.

[0017] The culture medium is not particularly limited as long as it has an appropriate composition for culturing microorganisms, but is a liquid containing water as the main component and nutrients (e.g., vitamins, phosphoric acid, etc.) dissolved or dispersed in this water.

[0018] The temperature of the fermenter is preferably controlled to 40° C. or less. By controlling the temperature to 40° C. or less, the microorganisms in the fermenter do not die, and ethanol is efficiently produced by the raw material gas coming into contact with the microorganisms. The temperature of the fermenter is more preferably 38°C or lower, and in order to enhance the activity of the microorganisms, is preferably 10°C or higher, more preferably 20°C or higher, and even more preferably 30°C or higher.

[0019] The microorganism (species) that ferments the feed gas is not particularly limited as long as it can produce ethanol by microbial fermentation of the feed gas using carbon monoxide as the main feedstock. For example, the microorganism (species) is preferably one that produces ethanol from the feed gas through the fermentation action of gas-utilizing bacteria. Among gas-utilizing bacteria, the genus Clostridium is preferred, and Clostridium autoethanogenum is more preferred, from the viewpoints of gas utilization and culture stability. Examples are provided in more detail below.

[0020] Gas-utilizing bacteria include both eubacteria and archaebacteria. Examples of true bacteria include bacteria of the genus Clostridium, Moorella, Acetobacterium, Carboxydocella, Rhodopseudomonas, Eubacterium, Butyribacterium, Oligotropha, Bradyrhizobium, and the aerobic hydrogen-oxidizing bacteria Larsotonia.

[0021] On the other hand, examples of archaea include bacteria of the genus Methanobacterium, bacteria of the genus Methanobrevibacter, bacteria of the genus Methanocalculus, bacteria of the genus Methanococcus, bacteria of the genus Methanosarcina, bacteria of the genus Methanosphaera, bacteria of the genus Methanothermobacter, Metha Examples include bacteria of the genus Nothrix, bacteria of the genus Methanoculleus, bacteria of the genus Methanofollis, bacteria of the genus Methanogenium, bacteria of the genus Methanospirillium, bacteria of the genus Methanosaeta, bacteria of the genus Thermococcus, bacteria of the genus Thermofilum, bacteria of the genus Arcaheoglobus, and the like. Among these, as archaea, bacteria of the genus Methanosarcina, bacteria of the genus Methanococcus, bacteria of the genus Methanothermobacter, bacteria of the genus Methanothrix, bacteria of the genus Thermococcus, bacteria of the genus Thermofilum, and bacteria of the genus Archaeoglobus are preferred.

[0022] Furthermore, due to their excellent ability to assimilate carbon monoxide and carbon dioxide, archaea are preferably bacteria of the genus Methanosarcina, Methanothermobactor, or Methanococcus, with Methanosarcina or Methanococcus being particularly preferred. Specific examples of Methanosarcina bacteria include Methanosarcina barkeri, Methanosarcina mazei, and Methanosarcina acetivorans.

[0023] Among the gas-utilizing bacteria listed above, it is preferable to select and use bacteria with high ethanol production capacity, such as Clostridium autoethanogenum, Clostridium ljungdahlii, Clostridium aceticum, Clostridium carboxidivorans, Moorella thermoacetica, and Acetobacterium woodii.

[0024] Ethanol produced by microbial fermentation is obtained, for example, as an ethanol-containing liquid mixed with a culture solution. Ethanol can be separated from this ethanol-containing liquid using a separation device. Examples of separation devices include solid-liquid separators, distillation devices, and separation membranes, but it is preferable to use a solid-liquid separator and a distillation device in combination. Below, we will specifically explain the separation process performed using a solid-liquid separator and a distillation device in combination.

[0025] The ethanol-containing liquid obtained by microbial fermentation is separated in a solid-liquid separation device into a solid component mainly composed of microorganisms and a liquid component containing ethanol. The ethanol-containing liquid obtained by microbial fermentation contains, in addition to the target ethanol, microorganisms contained in the fermenter and their dead bodies as solid components, so solid-liquid separation is performed to remove these. Examples of solid-liquid separation devices include filters, centrifuges, and devices that use solution precipitation. The solid-liquid separation device may also be a device (e.g., a heat drying device) that evaporates the liquid component containing ethanol from the ethanol-containing liquid and separates it from the solid component. In this case, the liquid component containing the target ethanol may be entirely evaporated, or the liquid component may be partially evaporated so that the target ethanol is preferentially evaporated.

[0026] The liquid component separated by solid-liquid separation is further distilled in a distillation apparatus to separate the target product, ethanol. Separation by distillation allows for the production of large amounts of highly purified ethanol through simple operations. When distillation is performed, a known distillation apparatus such as a distillation column may be used. Furthermore, the distillation is performed, for example, so that the distillate contains the target product, ethanol, at a high purity, while the bottoms (i.e., the distillation residue) contains water as the main component (for example, 70% by mass or more, preferably 90% by mass or more). By performing the distillation in this manner, the target product, ethanol, and water can be largely separated.

[0027] The temperature inside the distillation apparatus during the distillation of ethanol is not particularly limited, but is preferably 100° C. or less, and more preferably about 70 to 95° C. By setting the temperature inside the distillation apparatus within the above range, it is possible to reliably separate ethanol from other components such as water. The pressure inside the distillation apparatus during ethanol distillation may be normal pressure, but is preferably less than atmospheric pressure, more preferably about 60 to 150 kPa (gauge pressure). By setting the pressure inside the distillation apparatus within this range, the ethanol separation efficiency can be improved, and the ethanol yield can be increased.

[0028] [Ethylene glycol made from carbon dioxide gas] Ethylene glycol can be produced from carbon dioxide gas by electrolysis. A method for producing ethylene glycol from carbon dioxide gas by electrolysis will be described below.

[0029] <Electrolysis> Electrolysis can be carried out, for example, using an electrolysis cell comprising an anode, a cathode, and an ion exchange membrane positioned to separate the anode and the cathode.

[0030] The anode causes an oxidation reaction of water (H2O) to produce oxygen (O2) and hydrogen ions (H +) or hydroxide ions (OH - ) to generate oxygen (O2) and water (H2O). On the other hand, the cathode reacts with the hydrogen ions (H + ) and electrons (e - ) to reduce carbon dioxide (CO2) and to produce carbon compounds such as ethylene glycol (C2H6O2). In this way, by reducing carbon dioxide on the cathode side of the electrolytic cell, ethylene glycol can be produced using carbon dioxide as a raw material.

[0031] The anode is preferably mainly composed of a catalytic material capable of reducing the overvoltage of the reaction that oxidizes water or hydroxide ions. Examples of such catalytic materials include metals such as platinum (Pt), palladium (Pd), and nickel (Ni), alloys and intermetallic compounds containing these metals, binary metal oxides such as manganese oxide (Mn-O), iridium oxide (Ir-O), nickel oxide (Ni-O), cobalt oxide (Co-O), iron oxide (Fe-O), tin oxide (Sn-O), indium oxide (In-O), ruthenium oxide (Ru-O), lithium oxide (Li-O), and lanthanum oxide (La-O), ternary metal oxides such as Ni-Co-O, Ni-Fe-O, La-Co-O, Ni-La-O, and Sr-Fe-O, quaternary metal oxides such as Pb-Ru-Ir-O and La-Sr-Co-O, and metal complexes such as Ru complexes and Fe complexes.

[0032] The cathode is preferably made of a catalytic material capable of reducing the overvoltage of the carbon dioxide reduction reaction. Examples of such catalytic materials include metals such as gold (Au), silver (Ag), copper (Cu), platinum (Pt), palladium (Pd), nickel (Ni), cobalt (Co), iron (Fe), manganese (Mn), titanium (Ti), cadmium (Cd), zinc (Zn), indium (In), gallium (Ga), lead (Pb), and tin (Sn), metal materials such as alloys and intermetallic compounds containing at least one of these metals, carbon materials such as carbon (C), graphene, CNT (carbon nanotubes), fullerene, and Ketjenblack, and metal complexes such as Ru complexes and Re complexes.

[0033] [Diol unit] The diol unit used in the present disclosure does not have to be limited to ethylene glycol made from at least one gas selected from the group consisting of carbon monoxide and carbon dioxide. That is, ethylene glycol made from at least one gas selected from the group consisting of carbon monoxide and carbon dioxide may be used in combination with another diol. Even when used in combination with another diol, the present disclosure aims to reduce the environmental impact as long as ethylene glycol made from at least one gas selected from the group consisting of carbon monoxide and carbon dioxide is used.

[0034] Other diols include diols derived from fossil fuels and diols derived from biomass.

[0035] As the fossil fuel-derived diol, a compound having two or more, preferably two to eight, hydroxyl groups per molecule can be used. Specifically, the fossil fuel-derived diol is not particularly limited and conventionally known compounds can be used, such as polypropylene glycol (PPG), neopentyl glycol (NPG), ethylene glycol (EG), diethylene glycol (DEG), butylene glycol (BG), hexamethylene glycol, triethylene glycol, dipropylene glycol, 1,4-cyclohexanedimethanol, 1,9-nonanediol, and 3-methyl-1,5-pentanediol. These may be used alone or in combination of two or more.

[0036] Examples of biomass-derived diols that can be used include aliphatic diols obtained from plant materials such as corn, sugarcane, cassava, and sago palm. Examples of biomass-derived aliphatic diols include polypropylene glycol (PPG), neopentyl glycol (NPG), ethylene glycol (EG), diethylene glycol (DEG), butylene glycol (BG), and hexamethylene glycol, all of which can be obtained from plant materials by the following methods. These may be used alone or in combination.

[0037] Biomass-derived polypropylene glycol is produced by a fermentation method in which glucose is obtained by decomposing plant raw materials, via 3-hydroxypropylaldehyde (HPA) from glycerol. Compared to polypropylene glycol produced by the EO production method, polypropylene glycol produced by a biomethod such as the fermentation method is preferable in terms of safety, as useful by-products such as lactic acid can be obtained, and production costs can be kept low. Biomass-derived butylene glycol can be produced by producing glycol from plant raw materials, fermenting the glycol, obtaining succinic acid, and then hydrogenating the resulting succinic acid. Biomass-derived ethylene glycol can be produced, for example, from bioethanol obtained by a conventional method via ethylene.

[0038] [Dicarboxylic acid unit] The dicarboxylic acid unit of the polyester is, for example, a dicarboxylic acid derived from a fossil fuel, and the fossil fuel-derived dicarboxylic acid may be, without limitation, an aromatic dicarboxylic acid, an aliphatic dicarboxylic acid, or a derivative thereof. Examples of aromatic dicarboxylic acids include terephthalic acid and isophthalic acid, and examples of derivatives of aromatic dicarboxylic acids include lower alkyl esters of aromatic dicarboxylic acids, specifically methyl esters, ethyl esters, propyl esters, butyl esters, etc. Among these, terephthalic acid is preferred, and dimethyl terephthalate is preferred as a derivative of aromatic dicarboxylic acid. Specific examples of aliphatic dicarboxylic acids include linear or alicyclic dicarboxylic acids typically having 2 to 40 carbon atoms, such as oxalic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, dodecanedioic acid, dimer acid, and cyclohexanedicarboxylic acid. Derivatives of aliphatic dicarboxylic acids include lower alkyl esters of the above aliphatic dicarboxylic acids, such as methyl esters, ethyl esters, propyl esters, and butyl esters, as well as cyclic acid anhydrides of the above aliphatic dicarboxylic acids, such as succinic anhydride. Among these, adipic acid, succinic acid, dimer acid, or a mixture thereof is preferred, with those containing succinic acid as the main component being particularly preferred. More preferred derivatives of aliphatic dicarboxylic acids include methyl esters of adipic acid and succinic acid, or a mixture thereof.

[0039] Furthermore, the dicarboxylic acid used in the dicarboxylic acid unit may be a dicarboxylic acid derived from biomass. Examples of biomass-derived dicarboxylic acids that can be used include aliphatic dicarboxylic acids obtained from plant materials such as renewable plant-derived oils such as soybean oil, linseed oil, tung oil, coconut oil, palm oil, and castor oil, as well as regenerated oils obtained by recycling waste cooking oils containing these oils as a main component. Examples of biomass-derived aliphatic dicarboxylic acids include sebacic acid, succinic acid, phthalic acid, adipic acid, glutaric acid, and dimer acid. For example, sebacic acid is produced by alkaline pyrolysis of ricinoleic acid obtained from castor oil, with heptyl alcohol as a by-product. Furthermore, biomass-derived aromatic dicarboxylic acids can be produced by, for example, producing isobutanol from corn, sugars, or wood, converting the isobutanol into isobutylene, dimerizing the isobutane to produce isooctene, synthesizing p-xylene through radical cleavage, recombination, and cyclization, and then oxidizing the resulting p-xylene (WO 2009 / 079213). When a biomass-derived dicarboxylic acid is used as the dicarboxylic acid unit, in the present disclosure, it is particularly preferable to use biomass-derived terephthalic acid.

[0040] The dicarboxylic acid used for the dicarboxylic acid unit may be a dicarboxylic acid produced from carbon dioxide gas. Terephthalic acid produced from carbon dioxide gas as a raw material can be used as a dicarboxylic acid produced from carbon dioxide gas. Terephthalic acid produced from carbon dioxide gas as a raw material can be produced, for example, by producing p-xylene from carbon dioxide gas and hydrogen gas as raw materials using a composite catalyst containing chromium oxide and a specific H-ZSM-5 zeolite, and then oxidizing the p-xylene (Japanese Patent Laid-Open Publication No. 2019-205969).

[0041] These dicarboxylic acids can be used alone or in combination of two or more.

[0042] The polyester may be a copolymerized polyester containing the diol unit and dicarboxylic acid unit, as well as a third copolymerization component. Specific examples of the copolymerization component include a bifunctional oxycarboxylic acid, and at least one polyfunctional compound selected from the group consisting of a trifunctional or higher polyhydric alcohol, a trifunctional or higher polycarboxylic acid and / or its anhydride, and a trifunctional or higher oxycarboxylic acid for forming a crosslinked structure. Among these copolymerization components, bifunctional and / or trifunctional or higher oxycarboxylic acids are particularly preferred because they tend to facilitate the production of copolymerized polyesters with a high degree of polymerization. Among these, the use of trifunctional or higher oxycarboxylic acids is most preferred because a very small amount of the oxycarboxylic acid can easily produce a polyester with a high degree of polymerization without the need for a chain extender, as described below.

[0043] The polyester may also be a high-molecular-weight polyester obtained by chain-extending (coupling) these copolymer polyesters. Chain extenders such as carbonate compounds and diisocyanate compounds can also be used, but the amount thereof is usually 10 mol % or less, preferably 5 mol % or less, and more preferably 3 mol % or less of carbonate bonds and urethane bonds relative to 100 mol % of all monomer units constituting the polyester.

[0044] Specific examples of carbonate compounds include diphenyl carbonate, ditolyl carbonate, bis(chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carbonate, dimethyl carbonate, diethyl carbonate, dibutyl carbonate, ethylene carbonate, diamyl carbonate, dicyclohexyl carbonate, etc. In addition, carbonate compounds derived from hydroxy compounds such as phenols and alcohols, and composed of the same or different hydroxy compounds, can also be used.

[0045] Specific examples of the diisocyanate compound include known diisocyanates such as 2,4-tolylene diisocyanate, a mixture of 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate, diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate.

[0046] The polyester used in the present disclosure can be obtained by a conventionally known method of polycondensing the above-mentioned diol unit and dicarboxylic acid unit. Specifically, it can be produced by a general melt polymerization method in which an esterification reaction and / or transesterification reaction between the above-mentioned diol unit and dicarboxylic acid unit is carried out, followed by a polycondensation reaction under reduced pressure, or by a known solution heating dehydration condensation method using an organic solvent.

[0047] The amount of diol used in producing the polyester is substantially equimolar to 100 moles of dicarboxylic acid or its derivative, but is generally used in an excess of 0.1 to 20 mole % because distillates are generated during the esterification and / or transesterification reaction and / or polycondensation reaction.

[0048] The polycondensation reaction is preferably carried out in the presence of a polymerization catalyst. The timing of adding the polymerization catalyst is not particularly limited as long as it is before the polycondensation reaction, and the catalyst may be added when the raw materials are charged or when pressure reduction is initiated.

[0049] Polymerization catalysts generally include compounds containing metal elements from Groups 1 to 14 of the periodic table, excluding hydrogen and carbon. Specific examples include compounds containing organic groups, such as carboxylates, alkoxy salts, organic sulfonates, or β-diketonate salts, containing at least one metal selected from the group consisting of titanium, zirconium, tin, antimony, cerium, germanium, zinc, cobalt, manganese, iron, aluminum, magnesium, calcium, strontium, sodium, and potassium, as well as inorganic compounds, such as oxides and halides, of the aforementioned metals, and mixtures thereof. Among these, metal compounds containing titanium, zirconium, germanium, zinc, aluminum, magnesium, and calcium, and mixtures thereof, are preferred, with titanium compounds, zirconium compounds, and germanium compounds being particularly preferred. Furthermore, because the polymerization rate increases when the catalyst is in a molten or dissolved state during polymerization, compounds that are liquid during polymerization or soluble in ester oligomers or polyesters are preferred.

[0050] The titanium compound is preferably a tetraalkyl titanate, specifically tetra-n-propyl titanate, tetraisopropyl titanate, tetra-n-butyl titanate, tetra-t-butyl titanate, tetraphenyl titanate, tetracyclohexyl titanate, tetrabenzyl titanate, and mixed titanates thereof. Titanium (oxy)acetylacetonate, titanium tetraacetylacetonate, titanium (diisoproxide)acetylacetonate, titanium bis(ammonium lactate)dihydroxide, titanium bis(ethylacetoacetate)diisopropoxide, titanium (triethanolamine)isopropoxide, polyhydroxytitanium stearate, titanium lactate, titanium triethanolamine, butyl titanate dimer, and the like are also preferably used. Furthermore, titanium oxide and composite oxides containing titanium and silicon are also preferably used. Among these, tetra-n-propyl titanate, tetraisopropyl titanate, tetra-n-butyl titanate, titanium(oxy)acetylacetonate, titanium tetraacetylacetonate, titanium bis(ammonium lactate) dihydroxide, polyhydroxytitanium stearate, titanium lactate, butyl titanate dimer, titanium oxide, and titania / silica composite oxide (for example, product name: C-94 manufactured by Acordis Industrial Fibers) are preferred, and tetra-n-butyl titanate, polyhydroxytitanium stearate, titanium(oxy)acetylacetonate, titanium tetraacetylacetonate, and titania / silica composite oxide (for example, product name: C-94 manufactured by Acordis Industrial Fibers) are particularly preferred.

[0051] Specific examples of zirconium compounds include zirconium tetraacetate, zirconium acetate hydroxide, zirconium tris(butoxy)stearate, zirconyl diacetate, zirconium oxalate, zirconyl oxalate, potassium zirconium oxalate, polyhydroxyzirconium stearate, zirconium ethoxide, zirconium tetra-n-propoxide, zirconium tetraisopropoxide, zirconium tetra-n-butoxide, zirconium tetra-t-butoxide, zirconium tributoxyacetylacetonate, and mixtures thereof. Zirconium oxide and composite oxides containing, for example, zirconium and silicon may also be used. Among these, zirconyl diacetate, zirconium tris(butoxy)stearate, zirconium tetraacetate, zirconium acetate hydroxide, ammonium zirconium oxalate, potassium zirconium oxalate, polyhydroxyzirconium stearate, zirconium tetra-n-propoxide, zirconium tetraisopropoxide, zirconium tetra-n-butoxide, and zirconium tetra-t-butoxide are preferred.

[0052] Specific examples of germanium compounds include inorganic germanium compounds such as germanium oxide and germanium chloride, and organic germanium compounds such as tetraalkoxygermanium. From the viewpoints of cost and availability, germanium oxide, tetraethoxygermanium, and tetrabutoxygermanium are preferred, with germanium oxide being particularly preferred.

[0053] When a metal compound is used as a polymerization catalyst, the amount of catalyst used, expressed as the amount of metal relative to the polyester produced, is usually 5 ppm or more, preferably 10 ppm or more, and the upper limit is usually 30,000 ppm or less, preferably 1,000 ppm or less, more preferably 250 ppm or less, and particularly preferably 130 ppm or less. If the amount of catalyst used is too large, not only is it economically disadvantageous but the thermal stability of the polymer is reduced, while if the amount is too small, the polymerization activity is reduced, which makes it more likely that the polymer will decompose during polymer production. As for the amount of catalyst used here, the method of reducing the amount of catalyst used is a preferred embodiment, because the amount of terminal carboxyl groups in the polyester produced is reduced as the amount of catalyst used is reduced.

[0054] The reaction temperature for the esterification reaction and / or transesterification reaction between diol units and dicarboxylic acid units is usually in the range of 150 to 260°C, and the reaction atmosphere is usually an inert gas atmosphere such as nitrogen or argon. The reaction pressure is usually normal pressure to 10 kPa. The reaction time is usually about 1 to 10 hours.

[0055] In the above-mentioned production process, a chain extender (coupling agent) may be added to the reaction system. After the polycondensation is completed, the chain extender is added to the reaction system in a homogeneous molten state without a solvent, and reacted with the polyester obtained by polycondensation.

[0056] High-molecular-weight polyesters using these chain extenders (coupling agents) can be produced using known techniques. After polycondensation is complete, the chain extender is added to the reaction system in a homogeneous, molten state without a solvent and reacted with the polyester obtained by polycondensation. Specifically, a polyester with a higher molecular weight can be obtained by reacting the chain extender with a polyester prepolymer obtained by catalytically reacting a diol with a dicarboxylic acid, which has substantially hydroxyl end groups and a mass-average molecular weight (Mw) of 20,000 or more, preferably 40,000 or more. A prepolymer with a mass-average molecular weight of 20,000 or more can be produced with the use of a small amount of coupling agent without being affected by residual catalyst, even under harsh conditions such as a molten state, and therefore without forming gel during the reaction.

[0057] [Molded products] The molded article according to the present disclosure is obtained by molding the polyester. Examples of the molded article include compression molded articles, injection molded articles, blow molded articles, and thermoformed articles. The molded article also includes containers for storing articles. Specific examples of the container include bottles, vials, cups, trays, and packs. Examples of molded articles other than containers include pellets, films, sheets, chopsticks, cutlery, etc. Specific examples of cutlery include knives, forks, spoons, etc. To process polyester into a molded article, a conventional method for processing polyester into a molded article can be employed.

[0058] The molded article according to the present disclosure tends to have a lower Kjeldahl nitrogen content than molded articles made from conventional fossil fuel-derived polyesters. For example, the Kjeldahl nitrogen content of the molded article according to the present disclosure is preferably 18 μg / g or less, more preferably 16 μg / g or less, and even more preferably 15 μg / g or less. Furthermore, the Kjeldahl nitrogen content of the molded article according to the present disclosure is 0 μg / g or more, practically 1 μg / g or more, and more practically 3 μg / g or more. In the present disclosure, Kjeldahl nitrogen is nitrogen quantified in accordance with JIS K0102:2019 44.1 (Kjeldahl method) and 44.2 (indophenol blue absorptiometry). The specific method for measuring the Kjeldahl nitrogen content is measured by the method described in the Examples below.

[0059] Furthermore, the content of carbon dioxide molecules in the molded article according to the present disclosure tends to be higher than that in molded articles made from conventional fossil fuel-derived polyesters. For example, the content of carbon dioxide molecules in the molded article according to the present disclosure is 9.2 × 10 17 It is preferable that the number of particles is 9.4×10 17 More preferably, it is 9.6 × 10 17 It is more preferable that the content of carbon dioxide molecules in the molded article according to the present disclosure is 3.0 × 10 18 It is preferable that the number of particles is less than 2.7 × 10 18 It is more preferable that the number of particles is less than 2.5 × 10 18 It is more preferable that the number is not more than 1 / g. The content of carbon dioxide molecules in the polyester resin layer is measured by thermal desorption spectrometry-mass spectrometry (TDS-MS), specifically by the method described in the examples below.

[0060] [container] The structure of a container, which is one embodiment of a molded article according to the present disclosure, will be described below with reference to FIG.

[0061] 1 is a front view showing one embodiment of a container 40 according to the present disclosure. The container 40 comprises a mouth 41, a substantially cylindrical body 42, and a bottom 43. The body 42 is provided below and continuous with the mouth 41. The bottom 43 is provided below and continuous with the body 42. A neck 44 is located between the mouth 41 and the body 42. A shoulder 48 is located between the neck 44 and the body 42.

[0062] A threaded portion 46 for screwing on a cap (not shown) is provided on the outer periphery of mouth portion 41. An annular support ring 47 that protrudes outward is provided on the outer periphery of mouth portion 41 below threaded portion 46.

[0063] As described above, the body 42 is substantially cylindrical. A plurality of horizontal grooves 45 are formed in the body 42. The horizontal cross section of the shoulder 48 is substantially circular, and the area of the horizontal cross section of the shoulder 48 gradually increases from the neck 44 side toward the body 42 side.

[0064] A heel portion 49 is formed on the radially outer portion of the bottom portion 43. The heel portion 49 is provided in an annular shape over the entire circumferential area of the bottom portion 43. The heel portion 49 is the portion of the bottom portion 43 that is stretched to be the thinnest during blow molding.

[0065] The size of such container 40 is not limited, and the container may be of any size. The full capacity of container 40 may be, for example, 100 mL or more, 200 mL or more, or 300 mL or more. The full capacity of container 40 may be, for example, 600 mL or less, 550 mL or less, or 530 mL or less.

[0066] Furthermore, the thickness of the heel portion 49 of the bottom 43 is not limited to this, but may be, for example, 0.07 mm or more, 0.08 mm or more, or 0.09 mm or more. The thickness of the heel portion 49 may be, for example, 0.30 mm or less, 0.25 mm or less, or 0.20 mm or less. By making the thickness of the heel portion 49 0.30 mm or less, the weight of the container 40 can be reduced. On the other hand, by making the thickness of the heel portion 49 0.07 mm or more, it is possible to prevent the bottom 43 from popping out and becoming permanently deformed when the container 40 is placed in a vending machine or dropped.

[0067] From the viewpoint of the strength of the container, the cross-sectional thickness of the body 42 of the container 40 is preferably 0.05 mm or more, and more preferably 0.10 mm or more. On the other hand, from the viewpoint of reducing the amount of polyester used, the cross-sectional thickness of the body 42 of the container 40 is preferably 0.54 mm or less, and more preferably 0.50 mm or less. The cross-sectional thickness of the body 42 of the container 40 refers to the cross-sectional thickness of the container 40 at the point where the cross-sectional thickness of the body 42 is smallest.

[0068] In a container according to one embodiment of the present disclosure, the ratio of volume to mass (volume / mass) is preferably 5 mL / g or more, and more preferably 8 mL / g or more, from the viewpoint of moldability of the container. On the other hand, the volume / mass is preferably 50 mL / g or less, more preferably 45 mL / g or less, from the viewpoint of the strength of the container.

[0069] The container according to one embodiment of the present disclosure may have a single-layer structure or a multi-layer structure of two or more layers. When the container has a multi-layer structure, the layers may have the same composition or different compositions.

[0070] In one embodiment, the container may have a vapor-deposited film on its surface, thereby improving the gas barrier properties of the container. The vapor-deposited film may be located on the inner surface or the outer surface of the container, but is preferably located on the inner surface.

[0071] Examples of the vapor-deposited film include vapor-deposited films made of metals such as aluminum, inorganic oxides such as aluminum oxide, silicon oxide, magnesium oxide, calcium oxide, zirconium oxide, titanium oxide, boron oxide, hafnium oxide, and barium oxide, organic silicon compounds such as hexamethyldisiloxane, and hard carbon films such as DLC (Diamond Like Carbon) films. The hard carbon film made of DLC is also called i-carbon film or hydrogenated amorphous carbon film (aC:H), and is a hard carbon film.3 It is an amorphous carbon film that is mainly composed of bonds.

[0072] The thickness of the vapor-deposited film is not particularly limited, and can be, for example, 1 nm or more and 150 nm or less.

[0073] The vapor-deposited film can be formed by a conventionally known method, for example, physical vapor deposition (PVD) methods such as vacuum deposition, sputtering, and ion plating, and chemical vapor deposition (CVD) methods such as plasma-enhanced chemical vapor deposition, thermal chemical vapor deposition, and photochemical vapor deposition. The thickness of the deposited film can be measured at the body of the container and means the cross-sectional thickness of the deposited film at the point where the cross-sectional thickness is smallest. When the deposited film is multilayered, the thickness of the deposited film is the sum of the thicknesses of all the deposited films.

[0074] [Preform] In this specification, a preform is a preform prior to blow molding into a container. The preform according to the present disclosure is used to manufacture a container, which is one embodiment of the present disclosure. Accordingly, the preform according to the present disclosure is composed of a polyester using ethylene glycol as a diol unit and dicarboxylic acid as a dicarboxylic acid unit, the polyester being derived from at least one gas selected from the group consisting of carbon monoxide and carbon dioxide. By configuring the preform in this way, a molded article according to the present disclosure can be manufactured. The polyester and the like contained in the preform according to the present disclosure may be the same as that used in the molded article according to the present disclosure.

[0075] An embodiment of the structure of a preform according to the present disclosure will now be described with reference to FIG.

[0076] Fig. 2 is a schematic half-sectional view showing one embodiment of a preform 30 according to the present disclosure. As shown in Fig. 2, the preform 30 comprises a mouth portion 31, a body portion 32 connected to the mouth portion 31, and a bottom portion 33 connected to the body portion 32. Of these, the mouth portion 31 corresponds to the mouth portion 41 of the container 40 and has substantially the same shape as the mouth portion 41. The body portion 32 corresponds to the neck portion 44, shoulder portion 48, and body portion 42 of the container 40 and has a substantially cylindrical shape. The bottom portion 33 corresponds to the bottom portion 43 of the container 40 and has a substantially hemispherical shape.

[0077] The mouth 31 includes a threaded portion 34 that corresponds to the threaded portion 46 of the container 40 onto which a cap (not shown) is screwed, a cap 35 that is provided below the threaded portion 34, and a support ring 36 that is provided below the cap 35 and corresponds to the support ring 47 of the container 40. The shape of the mouth 31 may be any conventionally known shape.

[0078] The cross-sectional thickness of the body portion 32 of the preform 30 according to the present disclosure is preferably 1.3 mm or more, and more preferably 1.7 mm or more. On the other hand, the cross-sectional thickness of the body portion 32 of the preform 30 is preferably 4.7 mm or less, and more preferably 4.0 mm or less. By setting the cross-sectional thickness of the body portion 32 of the preform 30 within the above range, a molded article according to the present disclosure can be produced. The cross-sectional thickness of the body portion 32 of the preform 30 refers to the cross-sectional thickness at the point where the cross-sectional thickness of the body portion 32 of the preform 30 is smallest.

[0079] [spoon] The structure of a spoon, which is one embodiment of the molded product according to the present disclosure, will be described below with reference to FIG.

[0080] Spoon 50 comprises measuring portion 51 and handle portion 52. Measuring portion 51 and handle portion 52 are both integrally formed by polyester injection molding. The tip of measuring portion 51 is rounded. Handle portion 52 is gradually wider towards its end. Measuring portion 51 has a measuring space 53 that opens upward.

[0081] The thickness of measuring portion 51 and handle portion 52 may be the same or different. As an example, the thickness of measuring portion 51 is 1.2 mm, and the thickness of handle portion 52 is 1.4 mm. The thickness of measuring portion 51 and handle portion 52 can be designed appropriately depending on the weight of the object to be measured using spoon 50. The dimensions of measuring portion 51 and handle portion 52 can also be designed appropriately. [Example]

[0082] The present disclosure will be described in more detail below with reference to examples, but the present disclosure is not limited to the following examples.

[0083] [Example 1] We prepared pellets (intrinsic viscosity: 0.77 dL / g) of polyethylene terephthalate (PET) using ethylene glycol derived from carbon monoxide gas as the diol unit and terephthalic acid derived from fossil fuels as the dicarboxylic acid unit. These pellets are hereinafter also referred to as pellet A. Pellets A were fed into an injection molding machine and melted at 290°C, and the melt was then injected to produce the preform shown in Figure 2. The body of the preform had a thickness of 3.5 mm and a weight per unit area of 22 g. Next, the preform was heated to 110°C and subjected to biaxial stretch blow molding in a blow molding die to produce a container with a full capacity of 600 mL as shown in Figure 1. The cross-sectional thickness of the body of the container was 0.28 mm. In this way, a molded article of Example 1 in the form of a container was obtained.

[0084] [Example 2] Pellets A were fed into an injection molding machine and melted at 290°C, and the melt was then injected to produce the spoon shown in Figure 3. The thickness of the measuring part and the handle part were both 1.5 mm. In this way, a molded article of Example 2 in the form of a spoon was obtained.

[0085] [Comparative Example 1] Pellets (intrinsic viscosity: 0.77 dL / g) made of polyethylene terephthalate (PET) were prepared using fossil fuel-derived ethylene glycol as the diol unit and fossil fuel-derived terephthalic acid as the dicarboxylic acid unit. These pellets are hereinafter also referred to as pellets B. A molded article of Comparative Example 1 was obtained in the same manner as in Example 1, except that pellets B were used instead of pellets A.

[0086] Comparative Example 2 A molded article of Comparative Example 2 was obtained in the same manner as in Example 2, except that pellets B were used instead of pellets A.

[0087] [Kjeldahl nitrogen content measurement] Test pieces were cut out from each of the molded articles of Examples 1 and 2 and Comparative Examples 1 and 2, and the Kjeldahl nitrogen content of the test pieces was measured in accordance with JIS K0102:2019 44.1 (Kjeldahl method) and 44.2 (indophenol blue absorptiometry). The lower detection limit for Kjeldahl nitrogen content is 10 μg / g, and since no Kjeldahl nitrogen was detected in Example 1, the Kjeldahl nitrogen content in the molded product of Example 1 was determined to be less than 10 μg / g. The results are shown in Table 1.

[0088] [Measurement of carbon dioxide molecular content] For each of the molded articles of Examples 1 and 2 and Comparative Examples 1 and 2, a test piece having a mass of 35 mg was cut out. Thermal desorption mass spectrometry (TDS-MS) was performed under the following measurement conditions to measure the carbon dioxide molecule content of the test piece. The results are shown in Table 1. (Measurement conditions) ·Device name: Denshi Kagaku EMD-WA1000S / W type Four specimens were heated on the SiC stage. Ionization method: Electron Ionization (EI) Measurement mode: SCAN mode Measurement mass range (m / z): 1 to 200 ·Heating conditions: 50℃~100℃ Heating rate: 10℃ / min Holding temperature and holding time: 100°C for 30 minutes

[0089] [Buckling strength measurement] Each of the molded articles of Example 1 and Comparative Example 1 was filled with 600 mL of water as the content liquid, then sealed with a cap. A buckling strength test was conducted with each molded article held upright. A top load tester (buckling test device) EH-1000 manufactured by Ebic Corporation was used to measure the buckling strength. A load was applied from above the opening at a constant rate, and the maximum load at which the article reached a so-called yield state was taken as the buckling strength. The higher the buckling strength, the better the mechanical properties of the molded article. The results are shown in Table 1.

[0090] [Impact resistance test] Ten molded articles were prepared for each of Example 2 and Comparative Example 2, and each molded article was dropped horizontally from a height of 1.5 m 10 times and evaluated based on the following evaluation criteria. The results are shown in Table 1. (Evaluation criteria) A: None of the 10 molded products were broken, and the molded products had excellent mechanical properties. B: One or more of the ten molded products were broken, and the molded products did not have excellent mechanical properties.

[0091] [Table 1]

[0092] As is clear from Table 1 above, the molded articles according to the present disclosure, even though they are molded articles of polyesters containing ethylene glycol as diol units derived from carbon monoxide gas as a raw material, exhibit physical properties comparable in terms of mechanical properties to molded articles of conventional polyesters containing ethylene glycol as diol units derived from fossil fuels. Furthermore, it was found that polyester molded products in which ethylene glycol, which is derived from carbon monoxide gas as a raw material, is used as a diol unit, have a lower Kjeldahl nitrogen content and a higher carbon dioxide molecule content than polyester molded products in which ethylene glycol, which is derived from fossil fuels, is used as a diol unit. [Explanation of symbols]

[0093] 30 preforms 31 Mouth 32 Torso 33 Bottom 34 Threaded part 35 Turnip 36 Support Ring 40 containers 41 Mouth 42 Torso 43 Bottom 44 Neck 45 horizontal groove 46 Threaded part 47 Support Ring 48 Shoulder 49 Heel 50 spoons 51 Measuring part 52 Handle 53 Metric space

Claims

1. A molded article of a polyester comprising diol units and dicarboxylic acid units, The molded article, wherein the diol unit comprises ethylene glycol obtained from at least one gas selected from the group consisting of carbon monoxide and carbon dioxide.

2. The carbon dioxide molecule content is 9.2 x 10 １７ pieces / g or more 3.0×10 １８ The molded article according to claim 1, wherein the number of particles per gram is not more than 1 / g.

3. 3. The molded article according to claim 1, wherein the Kjeldahl nitrogen content is 18 μg / g or less.

4. The molded article according to claim 1 or 2, wherein the dicarboxylic acid unit comprises at least one selected from the group consisting of terephthalic acid derived from a fossil fuel, terephthalic acid derived from biomass, and terephthalic acid derived from carbon dioxide gas.

5. The molded article according to claim 1 or 2, which is a container.

6. A preform used in the production of the molded article according to claim 5.

Images