Cellulose ester composition containing a fluidizing agent

Abstract

A melt-workable cellulose ester compound is described, containing an ionic fluidizing agent that can reduce the plasticizer content and increase dimensional stability during heating. One or more stabilizers may also be included in the compound. The compound is particularly suitable for melt-working applications such as extrusion and can be molded into useful articles.

Description

[Background technology]

[0001] There is a need for bio-derived or biodegradable materials with physical properties that can compete with conventional plastics in a variety of applications. Cellulose acetate (CA) is a bio-derived and biodegradable resin and has been used in various melt-processed products. Cellulose acetate compositions used in the melt-processing and molding of articles typically contain a considerable amount of plasticizer to enable processing and impart rigidity to the molded articles. However, the addition of plasticizers has the disadvantage of reducing dimensional stability at heat compared to the base cellulose ester. If the plasticized CA composition does not effectively eliminate moisture absorption, the water in the article acts as a plasticizer, further reducing dimensional stability at heat. Because CA compositions have a low thermal deflection temperature (HDT) and high hygroscopicity, the use of cellulose ester materials is excluded in applications where molded articles are exposed to heat, moisture, and especially heat and moisture.

[0002] Many types of plasticizers exist for cellulose acetate. For example, triacetin is an efficient plasticizer for cellulose acetate, and its bio-derived and non-toxic properties make it a good candidate for applications that come into contact with food, such as disposable food service products. However, many plasticizers, including triacetin, are relatively polar, allowing the blended cellulose acetate to absorb a considerable amount of moisture, thereby reducing the HDT (Heat Degradation Thickness). Adding hydrophobic additives to cellulose acetate can provide low hygroscopicity and a high HDT even at high humidity levels. It is also possible to increase the rigidity of the material by reducing the level of plasticizer. However, if the amount of plasticizer is low, the melt fluidity decreases, which increases the risk of thermal decomposition due to increased pressure during processing or an increase in the melting temperature. [Overview of the Initiative]

[0003] By adding a fluidizing agent to the composition, cellulose esters such as cellulose acetate can be melt-processed with a smaller amount of plasticizer. In one embodiment, or in combination with any other embodiment referenced herein, the addition of a fatty acid salt and an optional stabilizer yields a formulation that improves the dimensional stability of the molded article during heating. The fatty acid salt may function to improve melt fluidity and suppress plasticization of the article by water. The advantage of fatty acid salts is that they are significantly less volatile than fatty acids, which may volatilize during melt-processing and re-condense on the apparatus, causing contamination, or re-condense in the air, causing inhalation irritation. Fatty acid salts may have better compatibility with cellulose acetate than many fatty acid esters such as triglycerides, diglycerides, and monoglycerides, which may seep to the surface or cause blooming.

[0004] In one embodiment, or in combination with any other embodiment referenced herein, a composition is provided comprising a) a cellulose ester, b) a plasticizer, and c) a fluidizing agent comprising a salt having a melting point of 100°C to 250°C.

[0005] In other embodiments, or in combination with any other embodiments referenced herein, a composition is provided comprising a) a cellulose ester, b) a plasticizer, and c) 0.3% by weight or more of a flow aid.

[0006] In other embodiments, or in combination with any other embodiments referenced herein, a composition comprising a) a cellulose ester, b) a plasticizer, c) a flow aid, and d) a carboxylic acid stabilizer is provided.

[0007] In other embodiments, or in combination with any other embodiments referenced herein, a composition is provided comprising a) a cellulose ester, b) a plasticizer, and c) a flow aid comprising a metal fatty acid salt.

[0008] In other embodiments, or in combination with any other embodiments referenced herein, a composition is provided comprising a) a cellulose ester, b) a plasticizer, and c) a flow aid comprising a magnesium fatty acid salt.

[0009] In other embodiments, or in combination with any other embodiments referenced herein, a composition comprising a) a cellulose ester, b) a plasticizer, and c) a fluidizing agent is provided. The composition has a thermal deflection temperature greater than 50°C when tested under low pressure at 100% relative humidity (RH) in accordance with ASTM D648 and ISO 75. [Brief explanation of the drawing]

[0010] [Figure 1] This is a schematic diagram showing a bio-derived product molding process according to an embodiment of the present invention. [Figure 2] This is a schematic diagram showing another bio-based product molding process according to an embodiment of the present invention. [Modes for carrying out the invention]

[0011] The embodiments generally relate to methods, systems, and compositions for forming bio-derived particulate materials (e.g., pellets), sheets, and articles. Figures 1 and 2 show exemplary steps including methods, systems, and compositions, which are described in further detail below.

[0012] Methods and Systems As shown in Figures 1 and 2, the raw materials may be introduced into a bio-based polymer manufacturing process for producing bio-based polymer materials. As used herein, the term “bio-based” refers to polymer materials that are composed of whole or primarily of bio-based products or renewable agricultural resources. In one embodiment, or in combination with any other embodiment referred to herein, the bio-based polymer material comprises one or more cellulose esters. The one or more cellulose esters may include cellulose acetate. In such embodiments, the raw materials may include pulp such as wood pulp and / or cotton pulp. The pulp may be dissolvable grade pulp and / or paper grade pulp. The cellulose in the pulp may be esterified, for example with acetic acid, to form bio-based cellulose ester polymers such as cellulose acetate polymer.

[0013] Next, the bio-derived polymer material can be introduced into a compounding process. In this process, the bio-derived polymer material can be mixed with plasticizers and flow aids, and optionally one or more other additives (e.g., stabilizers) to form a compound material containing a plasticized bio-derived polymer. One or more other additives may also be mixed with the polymer, plasticizer, and flow aid. For example, as shown in Figure 1, other materials (additives) may include, but are not limited to, stabilizers, physical blowing agents (multiple), chemical blowing agents (multiple) (and / or precursors), nucleating agents (multiple), surface modifying additives (multiple), pigments (multiple), fillers (multiple), and / or other additives (multiple). Mixing can be achieved by any known mixing technique, including, but not limited to, rolling in a cylindrical vessel, overhead stirring, sigma blade mixing, and tumbling.

[0014] The compounding process may include a particleization process. The particleization process may generally include mixing a bio-derived polymer material, a plasticizer, a fluidizing agent, and optionally other additives to form a mixed composition, and forming particulate material from that composition. Specifically, the particleization process may include a pelletizing process, and the particulate material may contain a number of pellets. The term “compounded CE material” means the cellulose ester material formed during the compounding process, which may include a mixture of cellulose ester, a plasticizer, a fluidizing agent, and optionally other additives. Furthermore, such compounded CE material may take the form of particulate material or pellets. It should be understood that, as used herein, the terms “particleization” or “particleization process” may be the same as, or at least include, “pelletization” or “pelletization process.” In some embodiments, the particleization process may include pelletization in a water tank, pelletization on an air-cooled belt, underwater pelletization, solvent compounding, and the like.

[0015] In one embodiment, or in combination with any other embodiment referred to herein, the plasticizer, flow aid, and other optional additives can be mixed with the cellulose ester by conventional melt-kneading techniques. Such techniques involve mixing the cellulose ester with the plasticizer, flow aid, and optionally other additives in a twin-screw extruder equipped with appropriate mixing elements at appropriate temperatures and pressures until, by the time the material is discharged from the extruder, a molten and uniformly combined cellulose ester mixture is obtained. The molten and kneaded cellulose ester mixture may then be extruded through a die having an orifice with a diameter of about 2 to 6 mm so as to extrude strands. These strands may then be cooled with water (e.g., via underwater pelletization) or air and cut at regular intervals to obtain uniform desired sizes and shapes called "pellets" or "granules". Although the present specification describes a process for forming a pelletized compound material, it will be understood that the compound material supplied to the article forming process may be in any physical form (e.g., pellets, powders, granules, fibers) according to some embodiments. Further, such compound materials may take the form of molten mixtures or particulate materials (e.g., pellets, powders, granules, fibers, etc.).

[0016] The compound material that may contain pellets of the bio-derived polymer plasticized as described above may then be introduced into the article forming process as shown in FIGS. 1 and 2. In one embodiment, or in combination with any other embodiment referred to herein, the article forming process includes a sheet manufacturing process. The sheet manufacturing process may include a foamed sheet manufacturing process. The sheet manufacturing process may include one or more zones / steps for manufacturing a sheet or film, which will be described in more detail below.

[0017] A molding process can be used to produce foamed materials and articles, or rigid (i.e., non-foamed) materials and articles. As shown in Figure 2, in one embodiment, or in combination with any other embodiments referred to herein, various additives can be introduced into one or more zones of the molding process. The molding process may include an extrusion section, a sheet forming section, and / or a thermoforming section.

[0018] In one embodiment, or in combination with any other embodiments referenced herein, the article forming process may include introducing a compound material into a heating and mixing zone to form a CE molten composition. The heating and mixing zone may include, but is not limited to, a closed mixer (e.g., a static mixer), a roll mill, a kneader, and / or an extrusion process. Other heating and mixing processes may be used. The extrusion process may include one or more extruders, which may include single-screw extruders and / or twin-screw extruders. Within the extruder(s), the compound CE composition may be introduced into the extruder barrel and conveyed by a screw(s) through a die that forms an extruder from the feed composition. The composition may be heated and at least partially melted as it is conveyed through the extruder barrel toward the die. Thus, the term “CE molten composition” is used herein to mean a cellulose ester-based feed composition melted into a fluid molten resin via the heating and mixing zone. Heating may be supplied by an external heater positioned along the outside of the extruder barrel. The shape of the extruded product is generally determined by the shape and size of the die head. The extruded product may be further shaped by downstream processes such as forming a mandrel and / or a thermoforming process.

[0019] One or more additives can be introduced into the CE molten resin during an article forming process such as a heating and mixing zone. For example, one or more physical blowing agents can be added to the CE molten resin by injecting a physical blowing agent into the composition being conveyed within an extruder barrel. Other components such as plasticizers and flow aids can also be introduced into the heating and mixing zone. When the heating and mixing zone includes an extruder, the CE molten resin is then directed through an extrusion die to obtain a cellulose ester-based extrudate, which can then be further processed to form a CE sheet or article. The extrusion process is generally as described above, but it should be understood that the article forming process can include one or more additional or alternative processes for manufacturing an article from the CE molten resin. Such processes can include, but are not limited to, profile extrusion, injection molding, thermoforming, injection blow molding, rotational molding, and melt spinning.

[0020] Referring again to FIGS. 1 and 2, the compositions described herein can be used in the manufacture of cellulose ester sheets and articles. The article can have one or more particularly advantageous properties. For example, the article can be biodegradable and / or compostable, and / or the article can have excellent mechanical properties (e.g., strength, density, cell size, absorption, etc.).

[0021] Composition The steps described above may include the preparation and processing of compositions that can be used in downstream processing to form useful articles. For example, in one embodiment, or in combination with any other embodiments referred herein, the article forming step may include particulate material comprising a biopolymer, a plasticizer, a flow aid, and optionally one or more additives, such as those described herein. In one embodiment, or in combination with any other embodiments referred herein, the supply material may, in combination with one or more additives, such as those described herein, provide a mixed composition comprising a biopolymer, a plasticizer, a flow aid, and one or more additives. In one embodiment, or in combination with any other embodiments referred herein, the biopolymer comprises a cellulose ester. Further details of composition components comprising a biopolymer (e.g., a cellulose ester), a plasticizer, a flow aid, optionally a stabilizer, and other optional additives are given below.

[0022] Some of the exemplary components listed below may be described under two or more categories, but they should be understood as being intended to be included as separate components. For example, although magnesium stearate is described as a flow aid and optionally as a surface modifier or inorganic physical nucleating agent, magnesium stearate may be included separately or added to the composition at different times and / or in different amounts to perform different functions of the composition.

[0023] It should be further understood that compositions according to embodiments of the present invention may include or omit certain components described herein that are suitable for a particular use. Other components not described herein may also be included without departing from the scope of the present invention. However, in one embodiment, or in combination with any other embodiment, the compositions may contain, or include, polyester additives having polybasic acids and polyhydric alcohols in amounts of less than 1% by weight, or less than 0.1% by weight.

[0024] Cellulose ester The cellulose esters used as described herein may be any known in the art. Cellulose esters that can be used in the embodiments herein generally contain repeating units of the following structure: [ka]

[0025] In the formula, R 1 , R 2 , and R 3 The substituent is independently selected from the group consisting of hydrogen, acetyl, propyl, or butyl. The substitution level of a cellulose ester is usually expressed in terms of the degree of substitution ("DS"), which is the average number of non-OH substituents per anhydrous glucose unit ("AGU"). Generally, conventional cellulose contains three hydroxyl groups in each substitutable AGU unit. Therefore, DS can have values ​​from 0 to 3. Natural cellulose is a large polysaccharide with a degree of polymerization of 250 to 5,000 even after pulping and purification, and therefore the assumption that the maximum DS is 3.0 is approximately correct. Since DS is a statistical mean, a value of 1 does not guarantee that all AGUs have one substituent. In some cases, unsubstituted anhydrous glucose may exist, some having two substituents, some three, and the value is usually a non-integer. Total DS is defined as the average number of all substituents per anhydrous glucose unit. The degree of substitution per AGU can also mean specific substituents, such as hydroxyl or acetyl. In one embodiment, or in combination with any other embodiment, n is an integer in the range of 25 to 250, or 25 to 200, or 25 to 150, or 25 to 100, or 25 to 75.

[0026] In one embodiment, or in combination with any other embodiment, the cellulose ester may have at least two anhydrous glucose rings and at least 50 to a maximum of 5,000 anhydrous glucose rings, or at least 50 to less than 150 anhydrous glucose rings. The number of anhydrous glucose units per molecule is defined as the degree of polymerization (DP) of the cellulose ester. In one embodiment, or in combination with any other embodiment, the cellulose ester may have an intrinsic viscosity (IV) of about 0.2 to about 3.0 deciliters / gram, or about 0.5 to about 1.8, or about 1 to about 1.5, measured at a temperature of 25°C for 0.25 grams of sample in 100 ml of a 60 / 40 wt solution of phenol / tetrachloroethane. In one embodiment, or in combination with any other embodiment, cellulose esters useful herein may have a DS / AGU of about 1 to about 3.0, about 2.2 to about 2.8, or 1 to less than 2.2, or 1 to less than 1.5, where the substituted ester is acetyl.

[0027] Cellulose esters can be produced by any method known in the art. An example of a cellulose ester production process is taught in Kirk-Othmer, Encyclopedia of Chemical Technology, 5th Edition, Vol. 5, Wiley-Interscience, New York (2004), pp. 394-444. Cellulose, the starting material for producing cellulose esters, can be obtained from a variety of grades and sources, including, among others, cotton linters, softwood pulp, hardwood pulp, corn fiber, and other agricultural sources, as well as bacterial cellulose.

[0028] One method for producing cellulose esters involves esterification of cellulose by mixing it with a suitable organic acid, acid anhydride, and catalyst. The cellulose is then converted to cellulose triester. Next, the cellulose triester can be hydrolyzed by adding a water-acid mixture, and then filtered to remove gel particles or fibers. Water is then added to the mixture to precipitate the cellulose ester. The cellulose ester may then be washed with water to remove reaction by-products, followed by dehydration and drying.

[0029] The hydrolyzed cellulose triesters may have three acetyl substituents. These cellulose esters can be prepared by a number of methods known to those skilled in the art. For example, cellulose esters can be prepared by heterogeneous acylation of cellulose in a mixture of carboxylic acid and anhydride in the presence of a catalyst such as H2SO4. Cellulose triesters can also be prepared by homogeneous acylation of cellulose dissolved in a suitable solvent such as LiCl / DMAc or LiCl / NMP.

[0030] Those skilled in the art will understand that the commercial term "cellulose triester" also includes cellulose esters that are not completely substituted with acyl groups. For example, cellulose triacetate commercially available from Eastman Chemical Company, Kingsport, TN, USA typically has a DS of about 2.85 to about 2.99.

[0031] After esterification of cellulose to triester, some of the acyl substituents may be removed by hydrolysis or alcohol decomposition to obtain a secondary cellulose ester. As mentioned earlier, the distribution of acyl substituents may be random or non-random depending on the specific method used. Alternatively, the secondary cellulose ester may be prepared directly without hydrolysis by using a limited amount of acylation reagent. This process is particularly useful when the reaction is carried out in a solvent that dissolves cellulose. All of these methods yield cellulose esters useful in the present invention.

[0032] In one embodiment, or in combination with any embodiment mentioned, cellulose acetate is a cellulose diacetate having a polystyrene-equivalent number-average molecular weight (Mn) of about 10,000 to about 100,000, as measured by gel permeation chromatography (GPC) using NMP as the solvent and polystyrene-equivalent Mn according to ASTM D6474. In one embodiment, or in combination with any other embodiment, the cellulose acetate composition, when measured by gel permeation chromatography (GPC) according to ASTM D6474 using NMP as the solvent, is 10,000 to 90,000, or 10,000 to 80,000, or 10,000 to 70,000, or 10,000 to 60,000, or less than 10,000 to 60,000, or less than 10,000 to 55,000, or 10,000 to 50,000, or less than 10,000 to 50,000, or less than 10,000 to 45,000, or 10,000 to 40,000, or 10,000 to 30,000, or 20,000. 00 to less than 60,000, or 20,000 to less than 55,000, or 20,000 to less than 50,000, or 20,000 to less than 50,000, or 20,000 to less than 45,000, or 20,000 to 40,000, or 20,000 to 35,000, or 20,000 to 30,000, or 30,000 to 60,000 It contains cellulose diacetate having a polystyrene-equivalent number-average molecular weight (Mn) of less than 00, or between 30,000 and less than 55,000, or between 30,000 and less than 50,000, or between 30,000 and less than 45,000, or between 30,000 and 40,000, or between 30,000 and 35,000.

[0033] The most common commercially available secondary cellulose esters are produced by forming cellulose triesters through the initial heterogeneous acylation of cellulose using an acid catalyst. After obtaining a homogeneous solution of the cellulose triester in the corresponding carboxylic acid, the cellulose triester is then subjected to hydrolysis until the desired degree of substitution is obtained. After isolation, random secondary cellulose esters are obtained, i.e., the relative degree of substitution (RDS) at each hydroxyl group is approximately equal.

[0034] Cellulose esters useful in the present invention can be prepared using techniques known in the art, or can be selected from various types of cellulose esters available from, for example, Eastman Chemical Company, Kingsport, TN, USA, such as Eastman® Cellulose Acetate CA398-30 and Eastman® Cellulose Acetate CA398-10, Eastman® CAP485-20 Cellulose Acetate Propionate, and Eastman® CAB381-2 Cellulose Acetate Butyrate.

[0035] In one embodiment, or in combination with any other embodiment, cellulose esters can be prepared by converting cellulose to cellulose esters using a reactant obtained from a recycled material, such as a recycled plastic-containing synthesis gas source. In one embodiment, or in combination with any other embodiment, such reactant may be a cellulose reactant comprising an organic acid and / or acid anhydride used in the esterification or acylation reaction of cellulose, as discussed herein.

[0036] In one embodiment of the present invention, or in combination with any other embodiment referred to herein, or in combination with any other embodiment referred to herein, a cellulose ester composition is provided comprising at least one regenerated cellulose ester, wherein the cellulose ester has at least one substituent on anhydrous glucose units (AU) derived from a regenerated material (e.g., recycled plastic-containing synthesis gas).

[0037] In one embodiment, or in combination with any other embodiment, the cellulose ester composition contains more than 25% by weight, more than 30% by weight, more than 35% by weight, more than 40% by weight, more than 45% by weight, or more than 50% by weight, based on the total weight of the cellulose ester composition. All of the above cellulose ester compositions contain 50-99% by weight, or 60-99% by weight, or 70-99% by weight, or 80-99% by weight, or 90-99% by weight, or 50-90% by weight, or 60-90% by weight, or 70-90% by weight, or 80-90% by weight, or 90-99% by weight, or 50-80% by weight, or 60-80% by weight, or 70-80% by weight, or 50-70% by weight, or 60-70% by weight, or 50-60% by weight, based on the total weight of the cellulose ester composition. In some embodiments, the cellulose esters used herein may include combinations, formulations, or mixtures of two or more different types of cellulose esters (i.e., cellulose mixed esters). For example, in some embodiments, the cellulose esters used herein may consist of a formulation of two or more cellulose esters having different DSACs. However, this formulation may have a total DSAC of 2.0–3.0, 2.2–2.8, or 2.3–2.7.

[0038] plasticizer In one embodiment, or in combination with any other embodiment, the cellulose ester compositions described herein may contain at least one plasticizer. The plasticizer is added, for example, to an initial polymer-containing composition that does not contain additives to form a modified polymer-containing composition by reducing the melt viscosity of the polymer-containing composition (e.g., a cellulose ester composition) and substantially lowering its glass transition temperature (Tg). In one embodiment, "substantially lowering Tg" means that, when the additive is in the range of 0.1 to 20% by weight, the Tg of the composition decreases by at least 0.25°C, 0.5°C, 1°C, 1.5°C, 2°C, 2.5°C, 3°C, 4°C, 5°C, 6°C, 7°C, 8°C, 9°C, or 10°C for each 1% by weight increase in the additive concentration. The plasticizer may lower the thermal deflection temperature of the composition in proportion to the amount of additive added to the composition (i.e., in proportion to the additive concentration).

[0039] Plasticizers for cellulose esters include glycerol triacetate (triacetin), glycerol diacetate (diacetin), dibutyl terephthalate, dimethyl phthalate, diethyl phthalate, polyethylene glycol (molecular weight 200-600), dibutyl tartarate, di-2-methoxyethyl phthalate, o-benzoyl ethyl benzoate, triethylene glycol dipropionate, 1,2-epoxypropylphenylethylene glycol, 1,2-epoxypropyl (m-cresyl)ethylene glycol, 1,2-epoxypropyl (o-cresyl)ethylene glycol, β-oxyethylcyclohexene carboxylate, bis(cyclohexanate)diethylene glycol, triethyl citric acid, polyethylene glycol, propylene glycol, polysorbate, sucrose octaacetate, acetylated triethyl citric acid, acetyl tributyl citric acid, Admex, trippropionine, Scandiflex, poloxamer copolymer, and polyethylene. Glycol succinate, diisobutyl adipate, polyvinylpyrrolidone, glycol tribenzoate, benzoate plasticizers (such as the Benzoflex® plasticizer series), poly(alkyl succinate) (e.g., poly(butyl succinate), polyethylene succinate), o-cresyl-p-toluenesulfonate, N-ethyltoluenesulfonamide, adipate plasticizers, soybean oil epoxides (such as the Paraplex® plasticizer series), sucrose plasticizers, dibutyl Examples include tilsevacate, tributyline, sucrose acetate isobutyrate, the Resoflex® plasticizer series, triphenyl phosphate (TPP), triethyl phosphate (TEP), glycolates (e.g., ethyl phthalylethyl glycolate "EPEG" and methyl phthalylethyl glycolate "MPEG"), methoxypolyethylene glycol, 2,2,4-trimethylpentane-1,3-diyrbis(2-methylpropanoate), and polycaprolactone. In some embodiments, the plasticizers used herein may include combinations or mixtures of two or more different types of plasticizers.

[0040] In one embodiment, or in combination with any other embodiment, the plasticizer is a food-compatible plasticizer. Food compatibility means that it complies with applicable food additive and / or food contact regulations, and the plasticizer is permitted for use or recognized as safe by at least one (national or regional) food safety regulatory authority (or organization), for example, listed in the 21 CFR Food Additive Regulations, or otherwise recognized by the U.S. FDA with a Certificate of Conformity (GRAS). In one embodiment, or in combination with any other embodiment, the food-compatible plasticizer is triacetin or polyethylene glycol (PEG) having a molecular weight of about 200 to about 600, or about 300 to 500. In one embodiment, or in combination with any other embodiment, possible examples of food-compatible plasticizers include triacetin, triethyl citrate, polyethylene glycol, benzoic acid esters, propylene glycol, polysorbate, sucrose octaacetate, acetylated triethyl citrate, tributyl acetyl citrate, Admex, trippropionine, Scandiflex, poloxamer copolymer, polyethylene glycol succinate, diisobutyl adipate, polyvinylpyrrolidone, and glycol tribenzoate.

[0041] In one embodiment, or in combination with any other embodiment, the plasticizer is a bio-derived and / or biodegradable plasticizer. Some examples of bio-derived and / or biodegradable plasticizers include triacetin, triethyl citrate, acetyl triethyl citrate, polyethylene glycol, benzoic acid-containing plasticizers such as the Benzoflex® plasticizer series, poly(alkyl succinates) such as poly(butyl succinate), polyethylene succinate, adipic acid-based plasticizers, soybean oil epoxides such as the Paraplex® plasticizer series, sucrose-based plasticizers, dibutyl sebacate, tributylin, plasticizers in the Resolflex® series, triphenyl phosphate, glycolic acid, polyethylene glycol, 2,2,4-trimethylpentane-1,3-diirbis(2-methylpropanoate), and polycaprolactone.

[0042] In one embodiment, or in combination with any other embodiment, the cellulose ester composition may contain a plasticizer selected from the group consisting of PEG and MPEG (methoxyPEG). The polyethylene glycol or methoxy polyethylene glycol composition has an average molecular weight of 200 to 600 daltons, and the composition is melt-workable, biodegradable, and disintegrable.

[0043] In one embodiment, or in combination with any other embodiment, the composition comprises polyethylene glycol or methoxyPEG having an average molecular weight of 300 to 550 daltons.

[0044] In one embodiment, or in combination with any other embodiment, the composition comprises polyethylene glycol having an average molecular weight of 300 to 500 daltons.

[0045] In one embodiment, or in combination with any other embodiment, the plasticizer does not contain a metal fatty acid salt.

[0046] In one embodiment, or in combination with any other embodiment, the plasticizer does not contain an ionic compound.

[0047] In one embodiment, or in combination with any other embodiment, the plasticizer has a melting point temperature of less than 100°C.

[0048] In one embodiment, or in combination with any other embodiment, the plasticizer may be present in an amount sufficient to enable the cellulose ester composition to be melt-processed (or thermoformed) in a conventional melt-processing apparatus to produce useful articles, such as disposable plastic products.

[0049] In one embodiment, or in combination with any other embodiment, the plasticizer is present in an amount of 1% to 20% by weight, based on the weight of the cellulose ester composition being 100% by weight. The plasticizer may be present in an amount of at least 1% by weight, at least 2% by weight, at least 3% by weight, at least 4% by weight, or at least 5% by weight, at least 6% by weight, at least 7% by weight, or at least 8% by weight and / or 20% by weight or less, 19% by weight or less, 18% by weight or less, 17% by weight or less, 16% by weight or less, 15% by weight or less, 14% by weight or less, 13% by weight or less, or 12% by weight or less.

[0050] Fluid-enhancing agent In one embodiment, or in combination with any other embodiment, the cellulose ester compositions described herein may contain at least one fluidizing agent. As used herein, the term “fluidizing agent” refers to additives other than plasticizers that reduce the melt viscosity of the composition, such as, for example, by the melt flow index (ASTM D1238 / ISO1133). Advantageously, including a fluidizing agent in combination with a plasticizer can reduce the melt viscosity more significantly than including the same amount of plasticizer alone. For example, in some embodiments, a cellulose ester composition containing 10% by weight of plasticizer and 2% by weight of fluidizing agent may have a lower melt viscosity than a cellulose ester composition containing 12% by weight of plasticizer and no fluidizing agent. In addition, or alternatively, a cellulose ester composition containing 10% by weight of plasticizer and 2% by weight of fluidizing agent may have the same melt viscosity as a cellulose ester composition containing 20% ​​by weight of plasticizer and no fluidizing agent.

[0051] In one embodiment, or in combination with any other embodiment referenced herein, a flow aid is added, for example, to an initial polymer-containing composition that does not contain additives, to form a modified polymer-containing composition by not substantially lowering the glass transition temperature (Tg) of the polymer-containing composition (e.g., a cellulose ester composition). In one embodiment, "not substantially lowering Tg" means that, when the additive is in the range of 0.1 to 10% by weight, the Tg decreases by 0.5°C, 1°C, 1.5°C, 2°C, 2.5°C, 3°C, 4°C, 5°C, 6°C, 7°C, 8°C, 9°C, or 10°C or less for each 1% by weight increase in the additive concentration. In one embodiment, the flow aid does not lower the thermal deflection temperature of the composition in proportion to the amount of additive added to the composition (i.e., in proportion to the additive concentration). In one embodiment, "not reducing HDT" means that, when the additive is in the range of 0.1 to 10% by weight, the HDT decreases to C, 0.5°C, 1°C, 1.5°C, 2°C, 2.5°C, 3°C, 4°C, 5°C, 6°C, 7°C, 8°C, 9°C, or 10°C or lower for each 1% by weight increase in the additive concentration. The fluidizer may enable compounding of cellulose ester materials such as cellulose acetate with a smaller amount of plasticizer compared to formulations that do not contain a fluidizer.

[0052] In one embodiment, or in combination with any other embodiment, the fluidizer is a salt. The fluidizer salt may be solid at ambient temperature for ease of handling, but melts during processing (e.g., compounding, extrusion, thermoforming, injection molding). The fluidizer may be a salt with a melting point of 100°C to 250°C. Thus, the fluidizer salt, with a melting temperature of 100°C to 250°C, may also be called an ionic molten product. When heated, the ionic solid salt melts to form a liquid (or molten) ionic compound.

[0053] The fluidizing agent preferably has relatively low volatility and / or low water solubility. Low volatility suppresses the volatilization of the fluidizing agent during melting, while low water solubility suppresses dissolution and minimizes the influence of water on the glass transition temperature (Tg) and thermal deflection temperature (HDT) of cellulose acetate. Relative volatility can be characterized according to thermogravimetric analysis (TGA). For example, in some embodiments, when the fluidizing agent is heated in air from 20°C to 300°C at a rate of 20°C / min, the fluidizing agent exhibits a weight loss of less than 20%, less than 15%, less than 10%, less than 5%, less than 2%, less than 1%, or substantially no weight loss (i.e., any measured weight loss is attributable solely to the loss of water content).

[0054] In one embodiment, or in combination with any other embodiment, the fluidizing agent may be an ionic molten material composed of both cationic and anionic species. The cation may be any cation, including organic or inorganic cations. Examples of organic cations include ammonium, imidazolium, pyridinium, pyrrolidinium, triazolium, phosphonium, piperidinium, morpholinium, tetrazolium, pyrazolium ions, sulfonium ions, or thiazolium ions. Amino acids, specifically arginine, lysine, or histidine, may function as cations. The cation may preferably be an inorganic cation. Examples of inorganic cations include ions from groups 1 to 12 of the periodic table, or ions derived from groups 1 to 2 of the periodic table. The anion may be any anion, including organic or inorganic anions. The anion may preferably be an organic anion. Amino acids, particularly aspartic acid and glutamic acid, may function as organic anions. The organic anion may preferably be a fatty acid with an alkyl chain length of C8-C26, or a C12-C18 fatty acid, or a mixture of C12-C18 fatty acids. The fatty acid may be synthetic or natural, linear or branched, saturated or unsaturated. Exemplary linear saturated natural fatty acids include stearic acid, lauric acid, palmitic acid, and myristic acid. The flow aid containing the fatty acid may also function as a mold release agent and / or hydrophobic additive for the melt-processed cellulose acetate composition.

[0055] In one embodiment, or in combination with any other embodiment, the flow aid may be an aluminum, calcium, magnesium, potassium, sodium, and / or zinc salt of a fatty acid. These may also function as a mold release agent and / or hydrophobic additive for the melt-processed cellulose acetate composition. The aluminum, calcium, magnesium, potassium, and sodium salts are preferably food additives permitted under the 21 CFR Food Additives Rules or generally considered safe (GRAS) by the U.S. FDA, and would be suitable as additives or flow aids in melt-processed articles used to contain food. The aluminum, calcium, and magnesium salts are preferably not water-soluble and resistant to leaching from the article. In particular, magnesium fatty acid salts tend to be compatible with plasticized cellulose acetate, forming a transparent or nearly transparent rigid article without producing a waxy surface bloom. The magnesium fatty acid salt may contain 1 to 2 molar equivalents of fatty acid. The fatty acid may have an alkyl chain length of C12 to C18, or may contain a mixture of fatty acids within this range. In one embodiment, or in combination with any other embodiment, the fluidizing agent comprises a mixture of two or more fatty acid salts. In one embodiment, or in combination with any other embodiment, the fluidizing agent comprises magnesium stearate alone or in a mixture with other metal fatty acid salts.

[0056] In one embodiment or in combination with any other embodiment, the flow aid does not contain an ester.

[0057] In one embodiment or in combination with any other embodiment, the flow aid includes an ionic compound.

[0058] In one embodiment, or in combination with any other embodiment, the flow aid has a melting point temperature above 100°C.

[0059] In one embodiment, or in combination with any other embodiment, the flow aid may be present in the compound CE composition or melt-worked composition in amounts greater than 0.3% by weight, greater than 0.4% by weight, greater than 0.5% by weight, greater than 0.6% by weight, greater than 0.7% by weight, greater than 0.8% by weight, greater than 0.9% by weight, greater than 1.0% by weight, greater than 1.1% by weight, greater than 1.2% by weight, greater than 1.3% by weight, greater than 1.4% by weight, or greater than 1.5% by weight, and / or in amounts of 10% by weight or less, 9% by weight or less, 8% by weight or less, 7% by weight or less, 6% by weight or less, or 5% by weight or less. The flow aid may be present in the composition in amounts from 1% by weight to 10% by weight. Such compositions may further contain the plasticizers and stabilizers described herein.

[0060] Stabilizer During compounding or other processing of the CE composition, one or more stabilizers may be included that can suppress or reduce thermal decomposition of the polymer composition and articles or undesirable properties resulting therefrom. In one embodiment, or in combination with any other embodiment, one or more stabilizers include an organic acid (or organic acid formulation). The organic acid (or formulation) may have a pKa greater than 3.

[0061] In one embodiment, or in combination with any other embodiment, the CE composition comprises one or more carboxylic acid stabilizers. Suitable stabilizers include organic carboxylic acids that can neutralize the alkalinity of the composition which may be colored during melt processing. For example, organic carboxylic acids include citric acid, succinic acid, adipic acid, fumaric acid, maleic acid, malic acid, lauric acid, oxalic acid, myristic acid, oleic acid, palmitic acid, and stearic acid, as well as combinations thereof.

[0062] In one embodiment, or in combination with any other embodiment, one or more stabilizers may be included in the compound CE composition or melt-processed composition in an amount of 0.1 to 10% by weight, 0.5 to 5% by weight, or 1 to 10% by weight, based on the total weight of the composition being 100% by weight.

[0063] Biodegradable polymers In one embodiment, or in combination with any other embodiment, the cellulose ester composition described herein comprises a BCE component comprising at least one biodegradable cellulose ester (BCE) which may comprise one or more of the cellulose esters described herein, and a biodegradable polymer component comprising at least one other biodegradable polymer (other than BCE). In one embodiment, or in combination with any other embodiment, the other biodegradable polymer can be selected from polyhydroxyalkanoates (PHA and PHB), polylactic acid (PLA), polycaprolactone polymer (PCL), polybutylene adipate terephthalate (PBAT), polyethylene succinate (PES), polyvinyl acetate (PVA), polybutylene succinate (PBS) and copolymers (such as polybutylene succinate-co-adipate (PBSA)), cellulose esters, cellulose ethers, starch, proteins, their derivatives, and combinations thereof. In one embodiment, or in combination with any other embodiment, the cellulose ester composition comprises two or more biodegradable polymers. In one embodiment, or in combination with any other embodiment, the cellulose ester composition contains a biodegradable polymer (other than BCE) in an amount of 0.1 to less than 50% by weight, or 1 to 40% by weight, or 1 to 30% by weight, or 1 to 25% by weight, or 1 to 20% by weight, based on the cellulose ester composition. In one embodiment, or in combination with any other embodiment, the cellulose ester composition contains a biodegradable polymer (other than BCE) in an amount of 0.1 to less than 50% by weight, or 1 to 40% by weight, or 1 to 30% by weight, or 1 to 25% by weight, or 1 to 20% by weight, based on the total amount of BCE and biodegradable polymer.In one embodiment, or in combination with any other embodiment, at least one biodegradable polymer has a weight-average molecular weight (Mw) measured by gel permeation chromatography (GPC) with methylene chloride as the solvent using a refractive index detector and a polystyrene standard, which is 10,000 to 1,000,000, or 50,000 to 1,000,000, or 100,000 to 1,000,000, and This includes PHA in the range of 250,000 to 1,000,000, or 500,000 to 1,000,000, or 600,000 to 1,000,000, or 600,000 to 900,000, or 700,000 to 800,000, or 10,000 to 500,000, or 10,000 to 250,000, or 10,000 to 100,000, or 10,000 to 50,000. In one embodiment, or in combination with any other embodiment, the PHA may include polyhydroxybutyrate-co-hydroxyhexanoate.

[0064] Nuclear agent A nucleating agent refers to a chemical or physical material that provides sites for cell formation in a mixture of molten formulations, such as within a molten CE resin. As will be described in more detail below, nucleating agents can be added to compound CE materials during the compounding process. Alternatively, or in addition, nucleating agents may be added during the manufacturing process of foamed sheets. For example, a nucleating agent may be compounded with the formulation introduced into the hopper of the extruder in the extrusion section. Alternatively, a nucleating agent may be added to the molten CE resin in the extruder itself. Examples of nucleating agents include physical nucleating agents and chemical nucleating agents. A physical nucleating agent is a substance that is immiscible with the polymer matrix of the molten CE resin at the extrusion temperature of the extrusion section. A chemical nucleating agent is a substance that reacts (e.g., decomposes) during extrusion (e.g., at the extrusion temperature in the extruder) to form a physical nucleating agent. Thus, a chemical nucleating agent can be considered (and referred to herein as) a precursor of a physical nucleating agent formed in situ.

[0065] Suitable physical nucleating agents include fine particles having a desirable particle size and / or shape to create cell nucleation sites within the molten CE resin. For example, in some embodiments, the physical nucleating agent has an average particle size of less than 1000 microns, less than 500 microns, less than 100 microns, less than 50 microns, less than 25 microns, less than 20 microns, less than 10 microns, less than 5 microns, less than 2 microns, less than 1.5 microns, and / or less than 1.0 micron. However, in some other embodiments, it may be preferable to have nanoscale-sized particles. Furthermore, in some embodiments, the physical nucleating agent preferably has a high aspect ratio (i.e., width:height). For example, in some embodiments, the physical nucleating agent has an average aspect ratio greater than 1:1, greater than 2:1, greater than 5:1, greater than 10:1, greater than 20:1, greater than 30:1, greater than 40:1, greater than 50:1, greater than 75:1, and / or greater than 100:1. Furthermore, as described above, the physical nucleating agent must be immiscible with the polymer matrix of the CE molten resin at the extrusion temperature of the extrusion section. Therefore, in some embodiments, the physical nucleating agent needs to have a melting temperature of at least 220°C, at least 230°C, at least 240°C, at least 250°C, at least 275°C, at least 300°C, at least 325°C, or at least 350°C. However, the physical nucleating agent may be selected to have the ability to recrystallize after cooling following melting.

[0066] Examples of suitable inorganic physical nucleating agents include, but are not limited to, talc, minerals such as CaCO3 and mica, and mixtures of at least two of the aforementioned. One representative example is a talc concentrate of Heritage Plastics HT6000 linear low-density polyethylene (LLDPE). Other inorganic physical nucleating agents include wollastonite, silica, silicon dioxide, titanium dioxide, magnesium oxide, aluminum oxide and calcium silicate, barium sulfate, kaolin, aluminum trihydrate ATH(Al(OH)3), MDH(Mg(OH)2), diatomaceous earth, magnetite / hematite, halloysite, zinc oxide, and titanium dioxide. In some embodiments, the inorganic nucleating agent will include oxides such as metal oxides or mixed metal oxides selected from one or more of aluminum oxide, antimony oxide, arsenic oxide, bismuth oxide, boron oxide, calcium oxide, gallium oxide, iron oxide, lithium oxide, magnesium oxide, silicon dioxide, and titanium dioxide. In other embodiments, the inorganic nucleating agent may include a silicate such as a silicate selected from one or more magnesium silicate and calcium silicate.

[0067] Natural particulate matter of bio-derived origin from renewable organic sources (e.g., organic nucleating agents) has also been found to function as effective physical nucleating agents. Natural substances that can be physical nucleating agents include substances composed of cellulose fibers and / or cellulose starch. Examples, but not limited to, include almond husk flour, animal fiber, apricot husk flour, bamboo flour, bark flour, shell flour, coconut husk flour, coconut fiber, cork flour, corn cob flour, corn cob grit, cottonseed husks, flocs and fibers, hazelnut husk flour, kenaf flour, natural fiber, nut shells and flour, oat fiber flour, olive stone flour, peanut shell flour, pecan husk flour, pine nut husk flour, pistachio nut husk flour, plant fiber, rice husk flour, rice husk grit, rice husk, soy flour, starch flour (hydrophobic), walnut husk flour, wheat husk, wheat hull, and wood flour. Other organic physical nucleating agents include cellulose powder, chitin, chitosan, metal stearate, carbon black, and dolomite.

[0068] As described above, a suitable chemical nucleating agent (or a precursor to a physical nucleating agent formed in situ) is configured to decompose when a threshold chemical reaction temperature is reached, generating cell nucleating sites in the CE molten resin. These small cells serve as nucleating sites for the proliferation of larger cells from physical or other types of blowing agents. In some embodiments, the precursor is configured to form a gas such as CO2 or N2 during the extrusion of the particulate material.

[0069] Examples of chemical nucleating agents include, but are not limited to, acids such as citric acid or citric acid-based materials. Other acids may include lauric acid, stearic acid, tartaric acid, ascorbic acid, propionic acid, and hexanoic acid. A typical example is HYDROCEROL™ CF-40E (available from Clariant Corporation), which contains citric acid and a nucleating agent. In some embodiments, the chemical nucleating agent includes a combination of acid and base, such as a carbonate, and examples of carbonates include sodium bicarbonate, zinc bicarbonate, potassium bicarbonate, sodium carbonate, and potassium carbonate. For example, a typical example of a chemical nucleating agent is a combination of citric acid and sodium bicarbonate. In some embodiments, the chemical nucleating agent may include a carrier in which the active ingredient of the nucleating agent is dispersed. For example, yet another typical example of a chemical nucleating agent is a combination of citric acid, sodium bicarbonate, and a carrier. In some embodiments, the carrier may include polystyrene. However, the carrier may include other compositions such as various biopolymers (e.g., polybutylene succinate, Capa polyester, etc.), polyolefins, and acrylic copolymers (e.g., ethylene methyl acrylate). In some such embodiments, citric acid and sodium bicarbonate may constitute about half (by weight) of the chemical nucleating agent, while the carrier constitutes the remaining half (by weight). Furthermore, in some such embodiments, there may be more sodium bicarbonate than citric acid in the chemical nucleating agent. For example, there may be about three times (by weight) more sodium bicarbonate than citric acid in the chemical nucleating agent. It should also be understood that in some embodiments, such as when the nucleating agent is hecofoam or hydrocerol, a carrier may not be required or used.

[0070] In one embodiment or in combination with any of the embodiments referenced herein, the nucleating agents are all present in amounts of 0.1 to 10% by weight, 0.1 to 5.0% by weight, at least 0.1% by weight, at least 0.25% by weight, at least 0.5% by weight, at least 1.0% by weight, at least 1.25% by weight, at least 1.5% by weight, at least 1.75% by weight, at least 2.0% by weight, at least 2.25% by weight, at least 2.5% by weight, at least 2.75% by weight, or at least 3.0% by weight, or at least 3.5% by weight, or at least 4.0% by weight, or at least 4.5% by weight, and / or less than 7.5% by weight, less than 5% by weight, less than 4% by weight, less than 3% by weight, less than 2% by weight, or less than 1.0% by weight, based on the total weight of the cellulose ester composition. In some embodiments, the nucleating agents used herein may include combinations or mixtures of two or more different types of nucleating agents.

[0071] It should be noted that cellulose ester materials, whether in the form of compound CE materials or CE molten resins, can generally tolerate a maximum amount of nucleating agent that can function to form nucleating sites. Any remaining nucleating agent added to the cellulose ester material remains as a filler. Depending on the type of filler used, the filler can provide various properties to the resulting cellulose ester foam and / or article. For example, some fillers can increase / decrease the density, ductility, Young's modulus, yield strength, thermal deflection temperature, permeability, impact resistance, elongation to fracture, adhesive properties, and biodegradability of the cellulose ester material. Fillers can also be used to alter the visual properties (e.g., color, opacity, etc.) and tactile properties (e.g., material continuity, surface roughness, etc.) of the cellulose ester material.

[0072] foaming agent A blowing agent refers to a physical or chemical material (or combination of materials) that acts to expand nucleating sites. Blowing agents may include chemical blowing agents, physical blowing agents, combinations thereof, or several types of chemical and physical blowing agents. Blowing agents function to reduce the density of the material by expanding cells formed in the molten mixture at nucleating sites. Blowing agents may, for example, be added to molten CE resin in an extruder. Bio-derived or biodegradable particulate natural fillers may absorb moisture due to their hygroscopic nature, carrying the absorbed water into the molten resin mixture, where it may act as a physical blowing agent.

[0073] Examples of physical blowing agents include H2O, N2, CO2, alkanes, alkenes, esters, ethers, ketones, argon, helium, air, or mixtures thereof. Furthermore, it has been surprisingly found that the hygroscopic properties of bio-derived or particulate natural fillers allow them to absorb moisture, carry the absorbed water into the molten resin mixture, and act as a physical blowing agent. Hygroscopic biodegradable natural fillers can be incorporated into the composition to absorb moisture before the foaming process, after which the water is released and acts as a physical blowing agent. Beneficially, water can also be used as a plasticizer for cellulose ester resins. Furthermore, in some embodiments, the physical blowing agent may include hydrocarbons such as pentane / isopentane or butane / isobutane. Other hydrocarbons may include propane, ethane, methane, hexane, cyclohexane, cyclopentane, or cyclobutene.

[0074] Chemical blowing agents are materials that decompose or react to produce gases (e.g., CO2 or N2). Such gases expand cells in the molten resin mixture and / or the resulting foam mixture, creating a structural material with multiple gaseous voids that are dispersed throughout. Chemical blowing agents can be endothermic or exothermic. Chemical blowing agents typically decompose and release gases at a certain temperature. Examples of chemical blowing agents include azodicarbonamides, acids (e.g., citric acid), and carbonates (e.g., sodium bicarbonate, sodium carbonate, ammonium bicarbonate, ammonium carbonate, zinc carbonate, etc.), and combinations thereof.

[0075] In one embodiment, or in combination with any other embodiment referred to herein, the foaming agent is 0.3 to 1.5% by weight, or 0.3 to 2.0% by weight, or 0.3 to 2.5% by weight, or 0.3 to 3.0% by weight, or 0.3 to 3.5% by weight, or 0.3 to 4.0% by weight, or 0.3 to 8%, or 1.3 to 1.5% by weight, or 1.3 to 2.0% by weight, based on the total weight of the cellulose ester composition. %, or 1.3-2.5% by weight, or 1.3-3.0% by weight, or 1.3-3.5% by weight, or 1.3-4.0% by weight, or 1.3-4.5% by weight, or 1.3-5.0% by weight, or 1.3-5.5% by weight, or 1.5-3.0% by weight, or 1.5-4.0% by weight, or 1.5-5.0% by weight, or 1.5-6.0% by weight, or 2.0-3.0% by weight, or 2.0-4.0% by weight, or 2. 0-5.0% by weight, or 2.0-6.0% by weight, or 2.5-3.0% by weight, or 2.5-4.0% by weight, or 2.5-5.0% by weight, or 2.5-6.0% by weight, or 3.0-4.0% by weight, or 3.0-5.0% by weight, or 3.0-6.0% by weight, or 0.0-9.0% by weight, or 0.5-9.0% by weight, or 1.0-9.0% by weight, or 1.5-9.0% by weight, or 2.0-9.0% by weight It is present in amounts of %, or 2.5 to 9.0% by weight, or 3.0 to 9.0% by weight, or 3.5 to 9.0% by weight, or 4.0 to 9.0% by weight, or 4.5 to 9.0% by weight, or 5.0 to 9.0% by weight, or 5.5 to 9.0% by weight, or 6.0 to 9.0% by weight, or 6.5 to 9.0% by weight, or 7.0 to 9.0% by weight, or 7.5 to 9.0% by weight, or 8.0 to 9.0% by weight, or 8.5 to 9.0% by weight. In some embodiments, the blowing agent used herein may include a combination or mixture of two or more different types of blowing agents.

[0076] Surface modification additives Surface modifiers refer to materials that can be added to cellulose ester compositions to improve their processability, thereby modifying the structure of the composition (or the resulting foamed article). For example, adding a surface modifier to a compound CE material (e.g., pellets in the compounding process) or a CE molten resin (e.g., in the extrusion process) can improve processability by reducing undesirable adhesion of the CE molten resin to the die or mandrel (or other components in the foamed sheet manufacturing process). Such a reduction in adhesion can be achieved by the surface modifier suppressing the fusion of cellulose esters caused by plasticizers. The addition of surface modifiers can also reduce blocking of cellulose ester foamed sheets produced in the sheet molding section. Furthermore, surface modifiers can also improve the foamed sheet manufacturing process by allowing the process to be carried out at lower temperatures.

[0077] Furthermore, in some embodiments, surface modification additives can function as antistatic additives to suppress electrical sparks or arc discharges in CE molten resins. Suppression of electrical sparks or arc discharges can be particularly important to reduce the possibility of hydrocarbons igniting and causing fires when hydrocarbons are used as blowing agents. Beneficially, surface modification additives can also reduce the diffusion of blowing agents, such as hydrocarbons, from foamed sheets or the resulting articles. In some embodiments, hydrocarbons themselves can be used as surface modification additives.

[0078] Nevertheless, more common examples of surface modifiers that can be used with compound CE materials (e.g., during the compounding process) or with CE molten resins (e.g., during the foam sheet manufacturing process) according to embodiments of the present invention include fatty acids such as palmitic acid, tallow acid, stearic acid, oleic acid, linoleic acid and linolenic acid, arachidic acid / behenic acid, behenic acid, and erucic acid. Surface modifiers may also include fatty acid amides such as erucamide, oleoamide, stearamide, benamide, ethanolamide, secondary amide, and bisamide.

[0079] Examples of additional surface modification additives may include glycerol esters and / or stearate esters such as monoglycerides, diglycerides, and triglycerides. Examples of monoglycerides include glycerol monostearate or monoglyceride derivatives (such as diacetyltartrate esters of mono and diglycerides (DATEM), ethoxylated monoglycerides, succinyl monoglycerides, and propylene glycol monoesters (PGME)). Examples of surface modification additives may also include metal stearate salts such as aluminum stearate, calcium stearate, lithium stearate, magnesium stearate, sodium stearate, zinc stearate, and / or combinations thereof (e.g., calcium stearate / zinc stearate). Examples of surface modifying additives include polyolefin waxes (polypropylene wax and polyethylene wax), olefin oxide waxes, ethylene-acrylic acid (EAA) copolymer waxes, ethylene-methyl acrylate (EMA) copolymer waxes, EAA ionomer waxes, acrylic waxes, and / or natural waxes, such as rice bran wax, sunflower wax, sugarcane wax, candelilla wax, soybean wax, beeswax, candelilla wax, and carnauba wax.

[0080] Other non-exclusive examples of surface modification additives include aliphatic diesters (e.g., dioctyl adipate), polyglycol diesters, alkyl alkyl ether diesters, aromatic triesters, polyester resins, chlorinated hydrocarbons, halogenated hydrocarbons, alkyl ether monoesters, and alkyl monoesters. Further, various oils such as aromatic oils, naphthenic oils, glyceride oils, silicone oils, and epoxidized oils (e.g., soybean oil and linseed oil) can be used as surface modification additives. Thus, in some embodiments, the surface modification additive includes plasticizers such as aliphatic diester plasticizers and polyester plasticizers. Further, in some embodiments, the surface modification additive may include polyhedral oligomeric silsesquioxane (POSS).

[0081] More generally, the surface modification additives used in embodiments of the present invention may be less polar than the cellulose ester in the compound CE material (e.g., during the compounding process) or the CE molten resin (e.g., during the foamed sheet manufacturing process). For example, the surface modification additive may have (based on the Hansen solubility parameter) a total solubility parameter δ of less than 25 MPa, less than 20 MPa, or less than 19.5 MPa; a dispersion force solubility parameter δ of less than 18 MPa, less than 16 MPa, or less than 14 MPa; and / or a bipolar intermolecular force solubility parameter δ of less than 12 MPa, less than 8 MPa, or less than 4 MPa; and / or a hydrogen bond solubility parameter δ of less than 11 MPa, less than 10 MPa, or less than 9 MPa. 1 / 2 less than, 20 MPa 1 / 2 less than, or 19.5 MPa 1 / 2 less than total solubility parameter δ; 18 MPa 1 / 2 less than, 16 MPa 1 / 2 less than, or 14 MPa 1 / 2 less than dispersion force solubility parameter δ d ; 12 MPa 1 / 2 less than, 8 MPa 1 / 2 less than, or 4 MPa 1 / 2 less than bipolar intermolecular force solubility parameter δ d ; and / or 11 MPa 1 / 2 less than, 10 MPa 1 / 2 less than, or 9 MPa 1 / 2 less than hydrogen bond solubility parameter δ hIt may have the following properties. On the other hand, in some other embodiments, the surface modification additive used in embodiments of the present invention may have higher polarity than the cellulose ester in the compound CE material (e.g., during the compounding process) or the CE molten resin (e.g., during the foam sheet manufacturing process). For example, the surface modification additive may have a polarity of 21.5 MPa (based on the Hansen solubility parameter). 1 / 2 Super, 23MPa 1 / 2 Over, or 25 MPa 1 / 2 The total solubility parameter δ may be greater than or equal to 200°C, 220°C, 240°C, 260°C, 280°C, or 300°C. Furthermore, the surface modification additive may have a molecular weight greater than 100 g / mol, 150 g / mol, 220 g / mol, 260 g / mol, 300 g / mol, or 340 g / mol, and / or less than or equal to 1000 g / mol, less than or equal to 2500 g / mol, or less than or equal to 5000 g / mol. Furthermore, it may be preferable that the surface modification additive is insoluble in the plasticizer(s) used in the cellulose ester composition. For example, it may be preferable that the surface modification additive is insoluble in triacetin. Finally, in some embodiments, the surface modification additive may be biodegradable and / or food-safe or FDA-approved.

[0082] In one embodiment, or in combination with any other embodiment referred to herein, the surface modifying additives are all present in amounts of 0.05 to 0.75% by weight, or 0.05 to 1.0% by weight, or 0.05 to 2.5% by weight, or 0.05 to 5.0% by weight, or 0.75 to 1.0% by weight, or 0.75 to 2.5% by weight, or 0.75 to 5.0% by weight, or 0.1 to 1.0% by weight, or 0.1 to 2.5% by weight, or 0.1 to 5.0% by weight, or 1.0 to 2.5% by weight, or 1.0 to 5.0% by weight, or 2.5 to 5.0% by weight, based on the total weight of the cellulose ester composition. In some embodiments, the surface modifying additives used herein may include a combination or mixture of two or more different types of surface modifying additives.

[0083] Goods In one embodiment, or in combination with any other embodiments referenced herein, a cellulose ester composition may be formed into a sheet and / or article in the article molding process described above. The sheet and / or article may be a foam or a rigid body. In some embodiments, the molded sheet may be further processed (e.g., thermoformed) into a useful article. In some embodiments, the article may be biodegradable and / or compostable, and / or may have excellent mechanical properties (e.g., strength, density, cell size, absorbency, etc.).

[0084] Exemplary articles comprising cellulose ester compositions are provided for use in food service and groceries, horticulture, agriculture, recreation, coatings, textiles, nonwovens, and home / office applications. Examples of food service and groceries include, but are not limited to, straws, cup lids, composite lids, portion cups, beverage cups, trays, bowls, plates, food containers, container lids, clamshell containers, cutlery, cooking utensils, stirrers, jars, jar lids, bottles, bottle caps, bags, flexible packaging materials, wraps, produce baskets, produce stickers, and strings. Examples of horticultural and / or agricultural applications include, but are not limited to, flower pots, seedling trays, transplanting pots, plant tags, buckets, soil and mulch bags, trimmer cords, agricultural films, mulch films, greenhouse films, silage films, compostable bags, film fixing stakes, and hay packing strings. Examples of recreational articles include, but are not limited to, toys, sporting goods, fishing gear, golf equipment, and camping equipment. Toys include, but are not limited to, beach toys, blocks, wheels, propellers, sippy cups, doll accessories, and pet toys. Sporting goods include, but are not limited to, whistles, whiffle balls, paddles, nets, foam balls, and darts, as well as artificial turf. Fishing equipment includes, but are not limited to, floats, lures, nets, and traps. Golf equipment includes, but are not limited to, tees, practice balls, ball markers, and divot tools. Camping equipment includes, but are not limited to, tent pegs, tableware, and cords / ropes. Examples of household and office goods include, but are not limited to, gift cards, credit cards, signatures, labels, report covers, mailing envelopes, tape, tool handles, toothbrush handles, writing instruments, combs, film cartridges, wire insulation, screw caps, and bottles.

[0085] In one embodiment, or in combination with any other embodiment referenced herein, the article is manufactured from a moldable thermoplastic material comprising the cellulose ester composition described herein.

[0086] In one embodiment, or in combination with any other embodiment referred to herein, the article is a disposable food contact article. Examples of such articles that can be made from a cellulose ester composition include cups, trays, multi-compartment trays, clamshell packaging materials, candy sticks, films, sheets, trays and lids (e.g., thermoformed products), straws, plates, bowls, portion cups, food packaging materials, liquid transport containers, egg cartons, solid or gel transport containers, and cutlery. In one embodiment, the cellulose ester may be a coating or layer of the article. The article may contain fibers. In an embodiment, the article may be a horticultural article. Examples of such articles that can be made from a cellulose ester composition include flower pots, plant tags, mulch films, and agricultural ground coverings.

[0087] Articles formed using compositions according to embodiments of the present invention may advantageously exhibit desirable thermal stability properties. The thermal stability of an article may be characterized, for example, by the thermal deflection temperature of the composition when tested according to ASTM D648 and ISO 75. In one embodiment, or in combination with any other embodiment referred to herein, the CE composition has a thermal deflection temperature greater than 50°C, greater than 55°C, or greater than 60°C when tested according to ASTM D648 and ISO 75 under low-pressure conditions at 100% relative humidity (RH). Concepts of further inventions relating to compositions, processes, and systems for manufacturing pellets, sheets, and / or articles

[0088] In one embodiment, or in combination with any other embodiment referred to herein, the sheet or article is industrially compostable or compostable at home. In one subclass of this class, the sheet or article is industrially compostable. In one subclass of this subclass, the sheet or article has a thickness of less than 6 mm. In one subclass of this subclass, the sheet or article has a thickness of less than 3 mm. In one subclass of this subclass, the article has a thickness of less than 1.1 mm. In one subclass of this class, the sheet or article is compostable at home. In one subclass of this subclass, the sheet or article has a thickness of less than 6 mm. In one subclass of this subclass, the sheet or article has a thickness of less than 3 mm. In one subclass of this subclass, the sheet or article has a thickness of less than 1.1 mm. In one subclass of this subclass, the sheet or article has a thickness of less than 0.8 mm. In one subclass of this subclass, the sheet or article has a thickness of less than 0.6 mm. In one subclass of this subclass, the sheet or article has a thickness of less than 0.4 mm.

[0089] In one embodiment, or in combination with any other embodiment referred to herein, the thickness of the sheet or article is 1–10 mm, 1–8 mm, 2–8 mm, 3–7 mm, 4–6 mm, about 4 mm, about 5 mm, about 6 mm, about 7 mm, or about 8 mm. However, it should be noted that the sheet or article may have other, larger sizes. For example, in some embodiments, the sheet or article may have a thickness of 0.5–24 inches, 1–15 inches, or 3–12 inches.

[0090] Compositions used to manufacture biodegradable cellulose acetate sheets and articles may include other additives such as fillers, odor modifiers, waxes, compatibilizers, biodegradation accelerators, dyes, pigments, colorants, lubricants, antioxidants, viscosity modifiers, antifungal agents, antimicrobial agents, softeners, release agents, ultraviolet absorbers, and combinations thereof. Each additional additive may be present in the cellulose ester material in amounts of less than 10% by weight, less than 5% by weight, less than 4% by weight, less than 3% by weight, less than 2% by weight, or less than 1.0% by weight.

[0091] As described above, it should be understood that the same type of compound or material may be identified with or included in multiple component categories in a cellulose ester composition. For example, polyethylene glycol (PEG) can function as a plasticizer or as an additive that does not function as a plasticizer, such as a hydrophilic polymer or a biodegradation accelerator. For instance, low molecular weight PEG has a plasticizing effect, while high molecular weight PEG functions as a hydrophilic polymer but does not have a plasticizing effect.

[0092] In one embodiment, or in combination with any other embodiment referred to herein, the composition further comprises a photocatalyst. In one class of this embodiment, the photocatalyst is titanium dioxide or iron oxide. In one subclass of this class, the photocatalyst is titanium dioxide. In one subclass of this class, the photocatalyst is iron oxide.

[0093] In one embodiment, or in combination with any other embodiment referenced herein, the composition further comprises a pigment. In one class of this embodiment, the pigment is titanium dioxide, carbon black, or iron oxide. In one subclass of this class, the pigment is titanium dioxide. In one subclass of this class, the pigment is carbon black. In one subclass of this class, the pigment is iron oxide. In one subclass of this class, the pigment is a biodegradable particulate natural filler.

[0094] definition It should be understood that the following is not intended to be an exclusive list of the terms to be defined. Other definitions, for example, when used in context, may be provided in the explanations above.

[0095] As used herein, the terms "a," "an," and "the" mean one or more.

[0096] As used herein, the terms “comprising,” “comprises,” and “comprise” are open-ended transitional clauses used to move the subject listed before the term to one or more elements listed after the term, and the elements listed after the transitional clause are not necessarily the only elements that constitute the subject.

[0097] As used herein, the term “flow aid” refers to additives other than plasticizers that reduce the melt viscosity of a composition, such as by measuring the melt flow index (ASTM D1238 / ISO1133).

[0098] As used herein, the term “bio-derived” means a material (e.g., polymer) that is composed entirely or largely of biological products or renewable agricultural materials.

[0099] To be considered "storable," a material must meet four criteria: (1) the material must meet the biodegradation requirements corresponding to an absolute biodegradation of 90% or a relative biodegradation of 90% relative to a control polymer in tests conducted under controlled composting conditions at high temperature (58°C) in accordance with ISO 14855-1 (2012); (2) the material must achieve a degree of disintegration of 90% when tested under aerobic composting conditions in accordance with ISO 16929 (2013); (3) the test material must meet all requirements regarding volatile solids, heavy metals, and fluorine as specified in ASTM D6400 (2012), EN 13432 (2000), and ISO 17088 (2012); and (4) the material must not adversely affect plant growth.

[0100] As used herein, the term “biodegradability” generally refers to the biological transformation and consumption of organic molecules. Biodegradability is an inherent property of the material itself, and materials may exhibit different degrees of biodegradability depending on the specific conditions to which they are exposed. The term “disintegrability” refers to the tendency of a material to physically decompose into smaller fragments when exposed to specific conditions. Disintegration depends on both the material itself and the physical size and composition of the article being tested. Ecotoxicity measures the effect of a material on plants, and the heavy metal content of a material is determined according to the procedures presented in standard test methods.

[0101] For a material to be considered "biodegradable," it must exhibit at least 90 percent biodegradation in total under household composting conditions, according to French standard NFT51-800 and Australian standard AS5810 (for example, compared to the initial sample), or at least 90 percent of the maximum biodegradation of a suitable reference material after reaching a plateau for both the reference and test items. The maximum test period for biodegradation under household composting conditions is one year.

[0102] To be considered "biodegradable" under industrial deposition conditions, at least 90% of the organic carbon in the entire product (or in each component present at more than 1% by dry mass) must be converted to carbon dioxide by the end of the test period, in accordance with ASTM D6400 and ISO 17088 standards, compared to the control or absolute value. According to European standard ED13432 (2000), the material must exhibit at least 90 percent biodegradation in total, or at least 90 percent of the maximum biodegradation of a suitable reference material after reaching a plateau for both the reference and test items. The maximum test period for biodegradability under industrial composition conditions is 180 days.

[0103] Under soil composting conditions compliant with Vincotte's "OK biodegradable SOIL" conformity mark and DIN CERTCO's "DIN Gepruft Biodegradable in Soil" certification scheme, a material must meet one of the following requirements to be considered "biodegradable": either it exhibits a biodegradation rate of 90% or more overall (e.g., compared to an initial sample), or, after both the reference material and the test material have reached a stable state, it exhibits a biodegradation rate of at least 90% of the maximum degradation rate of a suitable reference material. The maximum test period for biodegradation under soil composting conditions is two years.

[0104] In one embodiment, or in combination with any other embodiment referred to herein, the article is 0.643 g / cm³ 3 If the foam has a density of 25.4 mm × 25.4 mm × 1 mm, the article will exhibit at least 50%, or at least 55%, or at least 60%, or at least 65%, or at least 70%, or at least 75%, or at least 80%, or at least 85% disintegration under industrial or household composting test conditions, according to ISO 20200 standards. In one class of this embodiment, the article will exhibit 50% to 90%, or 55% to 90%, or 60% to 90%, or 65% to 90% disintegration under industrial or household composting test conditions, according to ISO 20200 standards. [Examples]

[0105] Example 1. Non-volatile fatty acid metal salts were synthesized from fatty acids and metal oxides or hydroxides. Magnesium salts of fatty acids were synthesized as non-volatile hydrophobic additives. A series of magnesium monofatty acid salts and difatty acid salts were prepared separately from lauric acid (C12), palmitic acid (C16), or stearic acid (C18). Then, a catalytic amount of acid was added to initiate the neutralization reaction. Magnesium hydroxide was dispersed in water (1 mole of Mg(OH)2 per liter of water) and heated to a temperature above the melting point of the fatty acid (usually 85°C). Citric acid (0.05 equivalents) was added as an initiator along with fatty acid (1 or 2 molar equivalents) to the magnesium hydroxide slurry, and the mixture was stirred to melt and mix the reactants. The mixture was reacted overnight at 85°C. The fatty acid salts were insoluble in water and precipitated as they were formed. The fatty acid salts were isolated from the reaction mixture by filtration and washed with DI water until the TDS (total dissolved solids measured by an electrical conductivity meter) of the filtrate was <20 ppm. The isolation yield was >93% based on the starting materials. The product is insoluble in triacetin (TA) or PEG400, and the reaction itself cannot be carried out using TA or PEG400 as a solvent.

[0106] Relative thermal stability and volatility were compared using thermogravimetric analysis (TGA). All fatty acid salts were solid and pre-dried at 50°C to remove excess moisture. The volatility of lauric acid alone was revealed by TGA. In the TGA curve, weight loss began at approximately 150°C, with its onset confirmed at 209°C, and a peak or maximum value of weight loss rate was shown at approximately 245°C. In contrast, the Mg fatty acid salts remained stable up to temperatures exceeding 300°C. Most of these preparations showed a weight loss of approximately 3% to 6% in the range of 80°C to 110°C, indicating signs of dehydration. However, the salts themselves were not volatile. [Table 1]

[0107] Sodium and calcium salts were synthesized from palmitic acid and stearic acid using the same method. Sodium hydroxide and calcium hydroxide did not require an acid initiator to form insoluble salts from fatty acids in water.

[0108] Example 2. Film press-molded from dried compound Dry formulations for press molding were prepared according to Table 2. A plasticizer was added to cellulose diacetate (CA398-30) powder along with optional additives, and the formulations were mixed in a coffee grinder. Each completely dry formulation was pre-weighed (5.0 g), placed in an aluminum pan, and dried at 60°C for 2 hours.

[0109] The film was pressed for a total of 4 minutes on a heated press with upper and lower plates preheated to 425°F (218°C). The pre-dried CA / TA / additive dry formulation was applied to the center of a 10 mil thick, 4-inch square frame sandwiched between upper and lower aluminum foil layers, and the entire assembly was sandwiched between two steel plates. The assembly was placed in the press and heated at 0 pressure for 1 minute to dry and pre-melt the powder, then pressed at 12,000 PHI (ram load: pounds) for 1 minute, gradually increasing to higher pressures over approximately 30 seconds, and finally held at 20,000 PHI for 2 minutes.

[0110] When the plasticizer content was low (10% triacetin (TA)), the melt-fluidity at 218°C was insufficient, and the frame was not completely filled during pressing. Adding 2% to 5% magnesium fatty acid salt resulted in good fluidity, allowing for sufficient frame filling and the production of transparent or nearly transparent films. In contrast, after adding 2% sodium fatty acid salt (Na), a very dark color was formed during pressure molding, whereas when 2% calcium stearate or zinc stearate was added, white or inclusions were clearly visible in the press-molded film. [Table 2]

[0111] Example 3. Compounding using a twin-screw extruder (with stabilizer) The formulations were prepared on a 1-pound (lb) scale, each containing 86% CA394-60S (ground), 10% triacetin, 2% fatty acid salts according to Table 3, and 1% citric acid and 1% palmitic acid as stabilizers. The materials were compounded in a Eurolab Prism extruder with a general-purpose screw design. The screw diameter was 16 mm, L / D = 40:1, and the screw length was 640 mm. The barrel temperature was set to 220 °C. Analysis performed on the pellets included triacetin content and melt flow index (MFI). [Table 3]

[0112] Comparative Example 3a. Unstabilized compounding

[0113] The formulations were compounded using a lab-scale twin-screw extruder according to Table 3a. CA394-60S was pre-ground. The pellets were dark brown and could not be pressed into film or injection molded as flex bars. [Table 4]

[0114] Example 4. Transparency of press-molded film For the film, press molding was performed from the compounded pellets of Example 3. The film was pressed for a total of 4 minutes on a heated press (PHI) with the upper and lower plates preheated to 425°F (218°C). The pellets were spread in the center of a 10 mil-thick, 4-inch square frame sandwiched between upper and lower layers of aluminum foil, and the entire frame was sandwiched between two steel plates. The assembly was placed in the press and heated at 0 pressure for 1 minute to dry and pre-melt the pack, then pressed at 12,000 PHI (ram load: pounds) for 1 minute, gradually increasing the pressure over approximately 30 seconds, and finally held at 20,000 for 1.5 minutes. Haze and clarity were measured using a hazeguard instrument (BYK). Transparency was quantified as color difference (delta E (CIE76)). Transparency was used as an indicator of suitability (Table 4). [Table 5]

[0115] Example 5. Compounding using a twin-roll mill or twin-screw extruder with a stabilizer. The compositions shown in Table 5A were pre-formulated on a 200g scale. CA394-60S was pre-ground. The formulations were compounded using a laboratory-scale two-roll mill (TRM) with a maximum residence time of 10 minutes. Back roll temperature: 205°C, front roll temperature: 215°C, roll gap: 20 microns.

[0116] The formulations shown in Table 5B were compounded into pellets using a twin-screw extruder (TSE) equipped with a 40 mm diameter high-mixing screw. The melting temperature was set to 225°C. CA394-60S was pre-ground. [Table 6] [Table 7]

[0117] Example 6. HDT at 100% RH to compare dimensional stability during heating. The compounded pellets from Example 5 were injection molded as flex bars for thermal deflection temperature (HDT) measurement according to ASTM D648. The low-pressure (LPRS) HDT of the flex bars was measured after equilibration at 20°C and 50% RH, and after 48 hours of equilibration at 20°C and 100% RH. [Table 8]

[0118] Example 7. Batch foaming To form pellets, two formulations (Table 7) were compounded in a twin-screw extruder using a high-mixing screw with a diameter of 40 mm. The melting temperature was set to 225°C. CA394-60S was then pulverized. [Table 9]

[0119] The film was pressed using a Carver heated press. The film was pressed for a total of 7 minutes on a heated press with the upper and lower plates preheated to 428°F (220°C). The compound was applied to the center of a 10 mil-thick, 4-inch square frame sandwiched between upper and lower layers of Kapton film, and the entire frame was sandwiched between two Teflon sheets. The assembly was placed in the press and heated at 0 pressure for 5 minutes to dry and pre-melt the material, then pressed at 10,000 PSI for 1 minute, gradually increasing the pressure over approximately 60 seconds, and finally held at 40,000 PSI for 1 minute.

[0120] The press-formed films were subjected to batch foaming. Batch foaming was carried out in a 300 mL high-pressure autoclave (Parr Instrument Company, Model No. 4561) with a thermocouple, 2.5 inches in diameter and 4 inches deep. The immersion tube, agitator shaft, and impeller were removed from the autoclave. In a typical experiment, 3 to 4 films with a thickness of 10 mil (1 inch x 1 inch) were placed on custom-made trays (length x width x height: 1.5 x 1.5 x 0.5 inches). Each tray contained one film, and these trays were stacked in the autoclave. The trays were made by folding Teflon-backed foil to the desired dimensions. The container was closed and tightly sealed, and then heated to the desired temperature, which could be in the range of 150°C to 230°C. After the desired temperature was reached, CO2 gas was pumped into the container through a supply valve to the desired pressure (50 to 130 bar). After the container reached equilibrium at the set temperature, it was stabilized for 30 minutes to allow sufficient time for the CO2 gas to penetrate the film. At the end of the holding time, the pressure was rapidly released to atmospheric pressure by purging with air through a valve on a 0.25-inch vent pipe. After the container cooled to room temperature, the foamed film was removed. The foamed film sample was placed in a Ziploc bag and stored in a refrigerator until subsequent tests were performed.

[0121] Example 8. Characterization of batch-foamed samples The foam samples from Example 7 were analyzed. The foam density was determined by measuring the density of batch foam samples using an XSR analytical balance equipped with a Mettler-Toledo density kit (model number 30460852). The weighing basket was placed on the density measurement attachment, and the beaker was placed on the base. The provided beaker was filled with DI water until the weighing basket was completely submerged. The provided thermometer was placed on the side of the beaker. Before use, the water was allowed to adjust to room temperature (approximately 10 minutes). The kit allows for density measurement of solid, liquid, porous, and suspended samples. The foam was punched out from a sheet using a 22 mm circular punch. The foam pieces were first weighed in air (placed on the tray on top of the kit) and then weighed while immersed in water (held in the basket). The balance used this information to calculate the density. Five measurements were taken for each sample, and the average density was calculated.

[0122] The cells were uniform and uniformly distributed. The average pore diameter was measured from SEM (scanning electron microscope) images. The pore diameter distribution was first calculated by manually tracing the pore contours on the SEM image of the foam sample using a computer mouse. Typically, 10 representative pores are selected to be traced in the image. Once the manual tracing step is complete, the rest is processed by an image processing algorithm that handles the tracing. The maximum diameter of the trace is determined in pixels by the algorithm. Then, the pixel diameter is converted to the actual diameter in microns using the image scale bar. The diameters were then averaged for each image, and the results are shown in Table 8. [Table 10]

[0123] Example 9. Comparison of TA 10% and 12% in sheet extrusion (1.5-inch killion). Sheets with a thickness of 20 mils were melt-extruded from material numbers 33 and 37. They were fed into a 12-inch wide die using a 1.5-inch diameter extruder. Films extruded from formulation number 33, containing 10% triacetin, were poorly processable, exhibited haze, and were very brittle. However, films extruded from the formulation containing 12% triacetin showed significantly improved processability, and the films were more transparent. [Table 11]

[0124] Example 10. Compounding and foam extrusion The mixture was compounded into pellets using a twin-screw extruder (TSE) equipped with a 40mm diameter high-mixing screw. The melting temperature was set to 225°C. CA394-60S was pre-ground. The composition of the compounded pellets was as follows: 86% by weight Eastman CA-398-30 or CA-394-60S 12% by weight of triacetin (plasticizer) 2% by weight of magnesium stearate (flow aid) 1% by weight of citric acid (stabilizing additive) 1% by weight of palmitic acid (stabilizing additive)

[0125] CA resin powder was compounded with a solid white powder additive in a bag and fed from the main feeder, while the liquid plasticizer was supplied to zone 2 of the extruder barrel using a liquid injector. The compounded strands were passed through a water trough and pelletized using a ConAir pelletizer. Typical twin-screw extrusion conditions are detailed in Table 10A below. The extruded pellets were then used for extruding foamed sheets, subsequent analysis, and thermoforming of prototypes. [Table 12]

[0126] The resulting pellets were then pre-dried overnight at 60°C prior to foam sheet extrusion. Foam extrusion was performed in a 1.5-inch Killion sheet extruder equipped with a Maddock mixing screw and an adjustable sheet / film flat die. The dried compounded pellets were bag-compounded with a similarly pelletized chemical blowing agent (Foamazol 73S, Bergen International) at a concentration of 1% by weight and fed into the extruder through a main feeder. Typical foam sheet extrusion conditions are detailed in Table 10B below. The foam sheets were extruded to a thickness of 40 mil (approximately 1 mm) and their bulk density was 0.643 g / cm³ using the procedure described in Example 8. 3 The sheet was measured and classified as a "medium-density" foam sheet. The cell morphology of the foam sheet was characterized using a scanning electron microscope (SEM) as described in Example 8. The average pore size was measured at 227 microns. In general, the lateral cells appeared to vary in size and have irregular shapes. Some foam cells also appeared to have fused with adjacent cells to form larger cells. [Table 13]

[0127] Example 11. Cobb test analysis to measure the water absorption and oil absorption properties of foamed sheets The amount of water and oil absorbed by the extruded foam sheet sample in Example 10, i.e., water absorption and oil absorption, was evaluated by performing the Cobb test. This test was modeled after ISO 535:2014(E) "Paper and board - Determination of water absorptiveness - Cobb method". A circular sample with a diameter of 6 cm was cut from the foam sheet and its weight was recorded (preliminary weight). It was then mounted in the test apparatus and secured to form a leak-free seal. Room temperature tap water was poured into the test cup and the sample was held for 30 minutes. The sample was then carefully removed from the cup, excess water was absorbed, and the sample was reweighed (post-weight). The difference between the post-weight and the primary weight was normalized by the sample surface area, and the weight was calculated in g / cm². -2 The water absorption value was calculated in units. The same procedure was performed using oil instead of water to calculate the oil absorption value. The extruded foam sheet of Example 10 of the composition described in the present invention had a water absorption value of 14 g / cm³. -2 and oil absorption value of 24 g / cm³ -2 Measurements were taken to show that...

[0128] Example 12. Measurement of the elastic modulus of a foamed sheet under high temperature and high humidity conditions. To measure the degree of stiffness reduction or modulus reduction of the extruded foam sheet in Example 10, dynamic viscoelasticity measurements (DMA) were performed under high temperature and high relative humidity (RH) conditions. The apparatus used was a DMA Q850 from TA Instruments, equipped with a film tension clamp and an RH control unit. A 1.12 mm thick specimen was cut and fixed to a width of 6.35 mm. The effective length of the specimen measured after sample loading was 10.74 mm. First, the temperature and RH were set to 80°C and 0, respectively, under a control load of 0 N to avoid applying stress / strain to the sample, and the sample was equilibrated for 240 minutes. After equilibration, vibration measurements were performed at a strain level of 0.1% and a frequency of 1 Hz. The same process was performed at 60% RH. Modulus data was recorded and compared for both RH levels tested. The extruded foam sample of Example 10 of the composition described in the present invention showed a 27% decrease in modulus as the RH increased from 0% to 60%.

[0129] Example 13. Evaluation of molten flow rheological properties and MFI of compounds with and without the addition of a flow aid. The small-amplitude vibration shear (SAOS) molten flow rheological properties of the compositions described in this invention were measured and compared with compounds prepared by varying the concentration of triacetin plasticizer without using any flow aid additives. The tests were performed using an ARES-G2 rotary rheometer manufactured by TA Instruments, with a 25 mm diameter stainless steel parallel plate geometry. The samples used in the tests were in pellet form. Frequency sweeps from 1 to 100 rad / s were performed at temperatures between 200°C and 230°C in 5°C steps, using a constant strain setting of 0.1%. The molten samples were immersed and equilibrated for 90 seconds at each temperature. The frequency sweep data obtained at different temperatures were converted to a reference temperature (T) according to the time-temperature conversion (TTS) principle. ref The temperature was shifted to 230°C, and master curves for complex viscosity (η*, Pa·s) and angular frequency (ω, rad / s) were created. The angular frequency axis (ω) of the master curve was then calculated using the Cox-Merz principle for shear rate (

number

number

[0130] The melt flowability of the compositions described in the present invention was also characterized by a melt flow index (MFI) test, compared with compounds prepared by varying the concentration of plasticizer without the use of any fluidizing agent additives. The MFI test was performed at 240°C using load weights of 2.16 kg and 5 kg, according to ASTM D1238. Table 13 also shows the MFI values ​​in g / 10 min for all compounds in this example. As is clear from Table 13, as the concentration of plasticizer decreases, η0 increases and MFI decreases. However, when a fluidizer is added to a low-plasticizer compound, η0 decreases and MFI increases, demonstrating that the addition of fluidizing agents is effective in improving the melt flowability of cellulose ester compounds. [Table 14]

[0131] Example 14. Testing the industrial and household compostability of foamed sheet samples obtained with and without the addition of a flow aid. The disintegration rate (%) of the extruded foam sheets in Example 10 was characterized in industrial (IC) and household composting (HC) environments according to the ISO 20200 method. The synthetic compost mixtures used in both tests were prepared according to the framework specified in the standard test method. The compost mixture was divided into two reactor boxes, and test samples were placed in them. The foam samples used were 1-inch x 1-inch square test pieces, corresponding to approximately 0.5% by weight of 1000g of the synthetic compost mixture. The industrial compost test was conducted for a total of 12 weeks, and the household compost test was conducted for 26 weeks. The protocols for mixing and adjusting the moisture content of the IC and HC compost mixtures were followed as specified in the ISO 20200 method. At the end of both the IC and HC tests, the compost was sieved, the remaining samples were collected and dried, and recorded for calculation of the % disintegration rate. Table 14 lists the disintegration performance of the test foam samples in the IC and HC tests. Foaming samples of the composition according to the present invention, which contain a flow aid, showed a higher degree of disintegration in both IC and HC tests compared to a control sample that did not contain a flow aid. [Table 15]

[0132] Claims not limited to the disclosed embodiments The preferred embodiments of the present invention described above are for illustrative purposes only and should not be used to limit the meaning of the interpretation of the scope of the invention. Modifications to the exemplary embodiments described above can be readily made by those skilled in the art without departing from the spirit of the invention.

[0133] The inventors hereby express their intention to determine and evaluate the reasonably fair scope of the invention on the basis of the doctrine of equivalents whenever the invention relates to any device that does not substantially deviate from, but falls outside, the literal scope of the invention as set forth in the following claims.

Claims

1. A composition, a) Cellulose ester and, b) Plasticizers and, c) The composition comprising a fluidizing agent containing a salt having a melting point of 100°C to 250°C.

2. The composition according to claim 1, further comprising a carboxylic acid stabilizer.

3. The composition according to claim 2, wherein the carboxylic acid stabilizer is citric acid, succinic acid, adipic acid, fumaric acid, maleic acid, malic acid, lauric acid, oxalic acid, myristic acid, oleic acid, palmitic acid, stearic acid, or a combination thereof.

4. The composition according to any one of claims 2 to 3, wherein the carboxylic acid stabilizer is citric acid.

5. The composition according to any one of claims 2 to 4, wherein the carboxylic acid stabilizer is present in an amount of 0.1 to 10% by weight, or 0.1 to 8% by weight, or 0.1 to 6% by weight, or 0.1 to 5% by weight, or 0.1 to 4% by weight, or 0.1 to 3% by weight, or 0.1 to 2% by weight, based on the total weight of the composition.

6. The aforementioned fluidizing agent is saturated or unsaturated (C ８－２８ A composition according to any one of claims 1 to 5, comprising a blend of fatty acid salts.

7. The aforementioned fluidizing agent is saturated or unsaturated (C ８－２８ A composition according to any one of claims 1 to 6, comprising a fatty acid salt.

8. The composition according to any one of claims 1 to 7, wherein the salt comprises a cation selected from the group consisting of ammonium ions, imidazolium ions, pyridinium ions, pyrrolidinium ions, triazolium ions, phosphonium ions, piperidinium ions, morpholinium ions, tetrazolium ions, pyrazolium ions, sulfonium ions, and thiazolium ions.

9. The composition according to any one of claims 1 to 7, wherein the salt comprises a cation selected from the group consisting of metal ions of Group 1 or Group 12.

10. The composition according to claim 9, wherein the metal is selected from the group consisting of magnesium, aluminum, calcium, potassium, sodium, and zinc.

11. The composition according to claim 10, wherein the metal is magnesium.

12. The composition according to claim 1, wherein the fluidizing agent is magnesium stearate or magnesium palmitate.

13. The composition according to any one of claims 1 to 12, wherein the flow aid is present in an amount of more than 0.1% by weight, or more than 0.15% by weight, or more than 0.2% by weight, or more than 0.25% by weight, or more than 0.3% by weight, or more than 0.35% by weight, or more than 0.4% by weight, or more than 0.45% by weight, or more than 0.5% by weight, or more than 0.55% by weight, or more than 0.6% by weight, or more than 0.65% by weight, based on the total weight of the composition.

14. The composition according to any one of claims 1 to 13, wherein the cellulose ester has a degree of substitution of hydroxyl substituents in the range of 0.4 to 0.

9.

15. The composition according to any one of claims 1 to 14, wherein the cellulose ester is cellulose acetate, cellulose propionate acetate, or cellulose acetate butyrate.

16. The composition according to any one of claims 1 to 15, wherein the cellulose ester is present in an amount of 50 to 98.7% by weight based on the total weight of the composition.

17. The aforementioned plasticizers include glycerol triacetate (triacetin), glycerol diacetate (diacetin), dibutyl terephthalate, dimethyl phthalate, diethyl phthalate, poly(ethylene glycol) with a molecular weight of 200 to 600, dibutyl tartrate, di-2-methoxyethyl phthalate, ethyl o-benzoyl benzoate, triethylene glycol dipropionate, 1,2-epoxypropylphenylethylene glycol, 1,2-epoxypropyl (m-cresyl)ethylene glycol, 1,2-epoxypropyl (o-cresyl)ethylene glycol, β-oxyethylcyclohexene carboxylate, bis(cyclohexanoic acid ester) diethylene glycol, triethyl citrate, polyethylene glycol, propylene glycol, polysorbate, sucrose octaacetate, acetylated triethyl citrate, acetyl tributyl citrate, Admex, trippropionine, Scandiflex, poloxamer copolymer, and polyethylene glycol succinate. Diisobutyl adipate, polyvinylpyrrolidone, glycol tribenzoate, benzoate-containing plasticizers, e.g., Benzoflex® plasticizer series, poly(alkyl succinate), e.g., poly(butyl succinate), polyethersulfone, o-cresyl p-toluenesulfonate, N-ethyltoluenesulfonamide, adipate-based plasticizers, soybean oil epoxide, e.g., Paraplex® plasticizer series, sucrose-based plasticizers, dibutyl sebacate, tributylin, sucrose A composition according to any one of claims 1 to 16, comprising rose acetate isobutyrate, Resolflex® plasticizer series, triphenyl phosphate (TPP), triethyl phosphate (TEP), glycolate (e.g., ethylphthalylethyl glycolate "EPE" and methylphthalylethyl glycolate "MPEG"), methoxypolyethylene glycol, 2,2,4-trimethylpentane-1,3-diirbis(2-methylpropanoate), or polycaprolactone.

18. The composition according to any one of claims 1 to 17, wherein the plasticizer is a food-grade plasticizer.

19. The composition according to any one of claims 1 to 18, wherein the plasticizer is present in an amount of 1 to 20% by weight based on the total weight of the composition.

20. A composition, a) 73-94.7% by weight of cellulose acetate, b) 5-20% by weight of triacetin, c) 0.5 to 5% by weight of magnesium palmitate or magnesium stearate, d) 0.2 to 2% by weight of citric acid, The composition, comprising all of the above based on the total weight of the composition.

21. An article comprising the composition according to any one of claims 1 to 20.

22. The article according to claim 21, wherein the article is a foam, pellet, granule, powder, sheet, or film.

23. An article comprising a composition, wherein the composition is a) 73-94.7% by weight of cellulose acetate, b) 5-20% by weight of triacetin, c) 0.5 to 5% by weight of magnesium palmitate or magnesium stearate, d) 0.2 to 2% by weight of citric acid, The article, comprising all of the above based on the total weight of the above composition.

24. The composition or article according to any one of claims 1 to 23, wherein the composition has a thermal deflection temperature of more than 50°C when tested under low pressure at 100% relative humidity (RH) in accordance with ASTM D648 or ISO 75.

25. The composition or article according to any one of claims 1 to 24, further comprising one or more physical blowing agents, chemical blowing agents, mineral fillers, alkalis, pigments, secondary plasticizers, and / or natural fillers.

26. The aforementioned article contains 0.643 g / cm³ ３ The article according to any one of claims 21 to 25, wherein the article is a 25.4 mm × 25.4 mm × 1 mm foam having a density of , and exhibits at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, or at least 85% disintegration under industrial or household composting test conditions, in accordance with ISO 20200 standards.

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