Cellulose ester mineral particle composition and method for reducing the molecular weight of cellulose ester therein

Abstract

The present application discloses a cellulose ester composition containing a specific mineral particle composition. When heated, the composition reduces the molecular weight of the cellulose ester in the composition depending on the temperature, time, and loading of the mineral particle composition. The present application also discloses a process for reducing the molecular weight of the cellulose ester in the cellulose ester composition containing the mineral particle composition.

Description

[Background technology]

[0001] Cellulose esters (CEs) are valuable polymers useful in many plastic, film, coating, and fiber applications. CEs are typically synthesized by reacting cellulose with an anhydride(s) in a solvent, hydrolyzing some of the ester groups to obtain a partially esterified product, and precipitating the product in a non-solvent. There are applications for both high and low molecular weight cellulose esters. Methods for reducing the viscosity of CEs often involve the presence of mineral acids and other catalysts that reduce the degree of polymerization of the CE during the synthesis or hydrolysis step. That is, the viscosity is modified during the process of CE synthesis and before final precipitation. It is also desirable to be able to modify the viscosity of CEs after they have been synthesized. We have surprisingly found that CE compositions containing acidic mineral additives can reduce the CE weight average molecular weight ("M"). w "), thus allowing the viscosity to be controlled during a separate compounding or other heat treatment step. w Alternatively, the viscosity is controlled by the temperature and duration of the heating step and the loading of acidic minerals on the CE. Summary of the Invention

[0002] This application is (i) a cellulose ester; (ii) a plasticizer; and (iii) a mineral particle composition; When the mineral particle composition is formulated into an aqueous suspension, the aqueous suspension exhibits a pH of less than 6; The plasticizer is present at 0-30 wt. %; the mineral particle composition is present in an amount of 0.1 to 40 wt. %; Each is based on the total weight of the cellulose ester composition.

[0003] The present application also discloses a process for reducing the weight average molecular weight ("Mw") of a cellulose ester, the process comprising: (1) (i) a cellulose ester; (ii) heating a composition comprising a mineral particle composition; When the mineral particle composition is formulated into an aqueous suspension, the aqueous suspension may comprise: exhibiting a pH of less than 6 at a temperature of at least 200°C; After heating, the Mw is reduced by at least 5%. DETAILED DESCRIPTION OF THE INVENTION

[0004] As used in the context of describing the present invention (particularly in the context of the claims that follow), the terms "a," "an," "the," and similar referents should be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The recitation of ranges of values ​​herein is merely intended to serve as a shorthand method for referring individually to each separate value falling within the range. Unless otherwise indicated herein, each separate value is incorporated herein as if set forth individually herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples or exemplary language (e.g., "etc.") provided herein is intended solely to better illuminate the invention and does not limit the scope of the invention as otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.

[0005] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limiting. Each group member may be referenced and claimed individually or in any combination with other members of the group or other elements found herein. It is anticipated that one or more members of a group may be included in, or deleted from, a group for reasons of convenience and / or patentability. When such inclusion or deletion occurs, the specification includes the group as modified and is thus deemed to fulfill all Markush-style group descriptions used in the appended claims.

[0006] Certain embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Of course, variations on these described embodiments will become apparent to those skilled in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as they see fit, and the inventors intend the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.

[0007] Additionally, throughout this specification, numerous references are made to patents, printed publications, journal articles, and other written texts (materials referenced herein). Each of the referenced materials is individually incorporated herein by reference in its entirety for the purposes of the referenced teachings, to the extent that they do not contradict any specific teachings provided herein.

[0008] It will be understood that the embodiments of the invention disclosed herein are illustrative of the principles of the invention. Other modifications that may be employed are within the scope of the invention. Thus, by way of example, but not of limitation, alternative configurations of the invention may be utilized in accordance with the teachings herein. Accordingly, the invention is not limited to that exactly as shown and described.

[0009] The details set forth herein are given by way of example and for purposes of illustrative description of preferred embodiments of the present invention only, and are presented to provide what is believed to be the most useful and readily understood explanation of the principles and conceptual aspects of various embodiments of the present invention. In this regard, no attempt has been made to show structural details of the present invention in more detail than is necessary for a fundamental understanding of the invention; the description taken in conjunction with the drawings and / or examples will make apparent to those skilled in the art how several forms of the present invention may be embodied in practice.

[0010] The definitions and explanations used in this disclosure are meant and intended to govern in any future constructions unless clearly and unambiguously modified in an example(s) or unless application of the meaning would make any construction meaningless or essentially meaningless. In the event that interpretation of a term would make it meaningless or essentially meaningless, definitions should be taken from Webster's Dictionary, Third Edition or a dictionary known to one of ordinary skill in the art.

[0011] composition The present application discloses a composition comprising (i) a cellulose ester, (ii) a plasticizer, and (ii) a mineral particle composition, wherein when the mineral particle composition is formulated into an aqueous suspension, the aqueous suspension exhibits a pH of less than 6, the plasticizer is present in an amount of 0 to 30 wt %, and the mineral particle composition is present in an amount of 0.1 to 40 wt %, each based on the total weight of the cellulose ester composition.

[0012] In one embodiment, or in combination with any other embodiment, the mineral particle composition comprises calcined kaolin, acid zeolite, bentonite, smectite, montmorillonite, silica, iron(II) oxide, sphalerite, pyrite, calcined diatomaceous earth, or combinations thereof. In a class of this embodiment, the mineral particle composition comprises calcined kaolin, acid zeolite, or calcined diatomaceous earth. In a class of this embodiment, the mineral particle composition comprises calcined kaolin. In a class of this embodiment, the mineral particle composition comprises calcined diatomaceous earth.

[0013] Calcined Kaolin: White kaolin clay is heat treated to remove some of its hydroxyl (OH) groups. Calcined kaolin is produced by heating ultrafine natural kaolinite to high temperatures in a kiln. The calcination process increases whiteness and hardness and modifies the size and shape of the kaolin particles. The calcination temperature controls many properties, including the pH of the suspension in water.

[0014] Calcined diatomaceous earth (DE) is typically treated at temperatures above 1000°C. This process converts amorphous silica to crystalline silica. This additional heat treatment fundamentally changes the composition of the opaline silica frustules. Calcination dehydrates the amorphous silica in DE and initiates its conversion to crystalline cristobalite. Heat treatment also reduces the surface area of ​​the diatoms by altering their physical shape. Calcined DE may be acid washed to reduce color and other impurities.

[0015] In one embodiment, or in combination with any other embodiment, the mineral particle composition has a particle size ranging from 0.1 microns to 200 microns, from 10 microns to 50 microns, or from 10 microns to 40 microns. In one embodiment, or in combination with any other embodiment, the mineral particle composition has a 0.1 to 30 wt.%, or 0.1 to 20 wt.%, or 0.1 to 10 wt.%, or 0.1 to 8 wt.%, or 0.1 to 6 wt.%, or 0.1 to 5 wt.%, or 0.1 to 4 wt.%, or 0.1 to 3 wt.%, or 0.1 to 2 wt.%, or 0.1 to 1 wt.%, or 0.5 to 30 wt.%, or 0.5 to 20 wt.%. %, 0.5 to 10% by weight, or 0.5 to 8% by weight, or 0.5 to 6% by weight, or 0.5 to 5% by weight, or 0.5 to 4% by weight, or 0.5 to 3% by weight, or 0.5 to 2% by weight, or 0.5 to 1% by weight, 1 to 30% by weight, or 1 to 20% by weight, 1 to 10% by weight, or 1 to 8% by weight, or 1 to 6% by weight, or 1 to 5% by weight, or 1 to 4% by weight, or 1 to 3% by weight, or 1 to 2% by weight, 2 to 30% by weight, or 2 to 20% by weight, 2 to 10% by weight, or 2 to 8% by weight, or 2 to 6% by weight, or 2 to 5% by weight, or 2 to 4% by weight, or 2 to 3% by weight, or 3 to 30% by weight, or 3 to 20% by weight, or 3 to 10% by weight, or 3 to 8% by weight, or 3 to 6% by weight, or 3 to 5% by weight, or 3 to 4% by weight, or 4 to 30% by weight, or 4 to 20% by weight, or 4 to 1 It is present at 0% by weight, or 4-8% by weight, or 4-6% by weight, or 4-5% by weight, or 5-30% by weight, or 5-20% by weight, or 5-10% by weight, or 5-8% by weight, or 5-6% by weight, or 6-30% by weight, or 6-20% by weight, or 6-10% by weight, or 6-10% by weight, or 6-8% by weight, or 7-30% by weight, or 7-20% by weight, or 7-10% by weight, or 7-8% by weight.

[0016] In one embodiment, or in combination with any other embodiment, the plasticizer is present in an amount of 0 to 30% by weight, or 0 to 25% by weight, or 0 to 20% by weight, or 0 to 15% by weight, or 0 to 10% by weight, or 0 to 5% by weight, or 0 to 3% by weight, or 0 to 2% by weight, or 0 to 1% by weight, or 0.1 to 30% by weight, or 0.1 to 25% by weight, or 0.1 to 20% by weight, or 0.1 to 15% by weight. %, or 0.1 to 10% by weight, or 0.1 to 5% by weight, or 0.1 to 3% by weight, or 0.1 to 2% by weight, or 0.1 to 1% by weight, or 0.5 to 30% by weight, or 0.5 to 25% by weight, or 0.5 to 20% by weight, or 0.5 to 15% by weight, or 0.5 to 10% by weight, or 0.5 to 5% by weight, or 0.5 to 3% by weight, or 0.5 to 2% by weight, or 0.5 to 1% by weight, or 1 to 30% by weight, or 1 to 25% by weight, or 1 to 20% by weight, or 1 to 15% by weight, or 1 to 10% by weight, or 1 to 5% by weight, or 1 to 3% by weight, or 1 to 2% by weight, or 2 to 30% by weight, or 2 to 25% by weight, or 2 to 20% by weight, or 2 to 15% by weight, or 2 to 10% by weight, or 2 to 5% by weight, or 2 to 3% by weight, or 5 to 30% by weight, or 5 % by weight, or 5-20% by weight, or 5-15% by weight, or 5-10% by weight, or 10-30% by weight, or 10-25% by weight, or 10-20% by weight, or 10-15% by weight, or 15-30% by weight, or 15-25% by weight, or 15-20% by weight, or 20-30% by weight, or 20-25% by weight, or 0% by weight (i.e., without plasticizer).

[0017] In one embodiment, or in combination with any other embodiment, the cellulose ester is cellulose acetate, cellulose acetate propionate, cellulose acetate butyrate, or a combination thereof.

[0018] In one embodiment, or in combination with any other embodiment, the cellulose ester is cellulose acetate propionate, cellulose acetate butyrate, or a combination thereof. In a class of this embodiment, the cellulose ester is cellulose acetate propionate. In a class of this embodiment, the cellulose ester is cellulose acetate butyrate. In a class of this embodiment, the plasticizer is present at 0 wt% (i.e., no plasticizer). In a class of this embodiment, the plasticizer is present at 0.1 to 10 wt%.

[0019] In one embodiment, or in combination with any other embodiment, the cellulose ester is cellulose acetate.

[0020] In one embodiment, or in combination with any other embodiment, the hydroxyl substituents of the cellulose esters ("DS OH ") has an average degree of substitution of 0.5 to 0.9, or 0.5 to 0.8, or 0.5 to 0.7, or 0.5 to 0.6, or 0.6 to 0.9, or 0.6 to 0.8, or 0.6 to 0.7, or 0.7 to 0.9, or 0.7 to 0.8, or 0.8 to 0.9.

[0021] In one embodiment, or in combination with any other embodiment, when the composition is extruded at a die temperature of 200°C with a residence time of 1 minute, the weight average molecular weight loss is less than 5%, and when the composition is extruded at a die temperature of 220°C with a residence time of 1 minute, the weight average molecular weight loss is greater than 5%.

[0022] In one embodiment, or in combination with any other embodiment, the composition is in the form of a pellet or powder. In a class of this embodiment, the composition is in the form of a pellet. In a class of this embodiment, the composition is in the form of a powder.

[0023] In one embodiment, or in combination with any other embodiment, the composition is in the form of a solution or suspension or coating. In one class of this embodiment, the composition is in the form of a solution. In one class of this embodiment, the composition is in the form of a suspension. In one class of this embodiment, the composition is in the form of a coating.

[0024] In one embodiment, or in combination with any other embodiment, the plasticizer is triacetin, triethyl citrate, polyethylene glycol, Benzoflex, propylene glycol, polysorbatemsucrose octaacetate, acetylated triethyl citrate, acetyl tributyl citrate, Admex, tripropionin, Scandiflex, poloxamer copolymer, polyethylene glycol succinate, diisobutyl adipate, polyvinylpyrrolidone, glycol tribenzoate, or a combination thereof.

[0025] In one embodiment, or in combination with any other embodiment, the plasticizer is selected from the group consisting of tris(chlorisopropyl)phosphate, tris(2-chloro-1-methylethyl)phosphate, trimethyl phosphate, triethyl phosphate, tributyl phosphate, triphenyl phosphate, tributyl-o-acetylcitrate, dibutyl tartrate, ethyl o-benzoylbenzoate, n-ethyl toluenesulfonamide, o-cresyl p-toluenesulfonate, aromatic diols, substituted aromatic diols, aromatic ethers, tripropionin, tribenzoin, glycerin esters, glycerol acetate benzoate, polyethylene glycol esters, polyethylene glycol diesters, di-2-ethylhexyl polyethylene glycol esters, glycerol esters, diethylene glycol, polypropylene glycol, polyglycol diglycidyl ether, dimethyl sulfoxide, N-methylpyrrolidinone, propylene carbonate, C1-020 dicarboxylic acid esters, dibutyl maleate, dioctyl maleate, Chill, resorcinol monoacetate, catechol, catechol esters, phenol, epoxidized soybean oil, castor oil, linseed oil, epoxidized linseed oil, difunctional glycidyl ethers based on polyethylene glycol, alkyl lactones, phospholipids, 2-phenoxyethanol, acetylsalicylic acid, acetaminophen, naproxen, imidazole, triethanolamine, benzoic acid, benzyl benzoate, salicylic acid, 4-hydroxybenzoic acid, propyl-4-hydroxybenzoate, methyl 4-hydroxybenzoate, ethyl 4-hydroxybenzoate, benzyl 4-hydroxybenzoate, glyceryl tribenzoate, neopentyl dibenzoate, triethylene glycol dibenzoate, trimethylolethane tribenzoate, butylated hydroxytoluene, butylated hydroxyanisole, sorbitol, xylitol, ethylenediamine, piperidine, piperazine, hexamethylenediamine, triazine, triazole, pyrrole, or a combination thereof.

[0026] In one embodiment, or in combination with any other embodiment, the plasticizer is a biodegradable plasticizer.Some examples of biodegradable plasticizers include triacetin, tripropionin, tributyrin, tribenzoin, triglyceride mixed esters, diglycerides, soybean oil epoxides such as the Vikoflex and Paraplex™ plasticizer series, triethyl citrate, acetyltriethyl citrate, polyethylene glycol (PEG), PEG esters and PEG ethers, benzoate ester plasticizers such as the Benzoflex™ plasticizer series, sucrose ester plasticizers, dicarboxylic acid esters and polyesters (adipate-based plasticizers, dibutyl sebacate), poly(alkyl succinates) such as poly(butyl succinate), polyethersulfone, polycaprolactone, polyester plasticizers such as the Resoflex™ and Paraplex™ series. and combinations thereof.

[0027] In one embodiment, or in combination with any other embodiment, the plasticizer is triacetin, triethyl citrate, polyethylene glycol, Benzoflex, propylene glycol, polysorbatemsucrose octaacetate, acetylated triethyl citrate, acetyl tributyl citrate, Admex, tripropionin, Scandiflex, poloxamer copolymer, polyethylene glycol succinate, diisobutyl adipate, polyvinylpyrrolidone, glycol tribenzoate, or a combination thereof.

[0028] In one embodiment, or in combination with any other embodiment, the plasticizer is triacetin, triethyl citrate, Benzoflex, propylene glycol, polysorbatemsucrose octaacetate, acetylated triethyl citrate, acetyl tributyl citrate, Admex, tripropionin, Scandiflex, poloxamer copolymer, polyethylene glycol succinate, diisobutyl adipate, polyvinylpyrrolidone, glycol tribenzoate, or a combination thereof.

[0029] In one embodiment, or in combination with any other embodiment, the plasticizer is triacetin.In one embodiment, or in combination with any other embodiment, the plasticizer is polyethylene glycol.

[0030] In one embodiment, or in combination with any of the mentioned embodiments, the cellulose acetate comprises at least one recycled cellulose acetate, the cellulose acetate having at least one substituent on an anhydroglucose unit (AU) derived from a recycled content material, for example, recycled plastic content syngas.

[0031] In one embodiment, or in combination with any other embodiment, the composition further comprises at least one of a filler, an additive, a biopolymer, a stabilizer, and / or an odor modifier. Examples of additives include waxes, compatibilizers, biodegradation accelerators, dyes, pigments, colorants, gloss control agents, lubricants, antioxidants, viscosity modifiers, antifungal agents, anti-fog agents, heat stabilizers, impact modifiers, antimicrobial agents, softeners, mold release agents, and combinations thereof.

[0032] process The present application discloses a process for reducing the weight average molecular weight ("Mw") of a cellulose ester, the process comprising: (1) heating a composition comprising (i) a cellulose ester and (ii) a mineral particle composition, wherein when the mineral particle composition is formulated into an aqueous suspension, the aqueous suspension exhibits a pH of less than 6 at a temperature of at least 200°C, and the Mw after heating is reduced by at least 5%.

[0033] In one embodiment, or in combination with any other embodiment, the heating occurs in an extruder or melt press. In a class of this embodiment, the heating occurs in an extruder. In a class of this embodiment, the heating occurs in a melt press.

[0034] In one embodiment, or in combination with any other embodiment, heating is for 15 seconds to 20 minutes, or 15 seconds to 10 minutes, or 15 seconds to 5 minutes, or 15 seconds to 3 minutes, or 15 seconds to 2 minutes, or 15 seconds to 1 minute, or 15 seconds to 50 seconds, or 15 seconds to 40 seconds, or 15 seconds to 30 seconds, or 15 seconds to 20 seconds, or 20 seconds to 20 minutes, or 20 seconds to 10 minutes, or 20 seconds to 5 minutes, or 20 seconds to 3 minutes, or 20 seconds to 2 minutes, or 20 seconds to 1 minute, or 20 seconds to 50 seconds, or 20 seconds to 40 seconds, 20 seconds to 30 seconds, or 30 seconds to 20 minutes, or 30 seconds to It is performed for 10 minutes, or 30 seconds to 5 minutes, or 30 seconds to 3 minutes, or 30 seconds to 2 minutes, or 30 seconds to 1 minute, or 30 seconds to 50 seconds, or 30 seconds to 40 seconds, or 40 seconds to 20 minutes, or 40 seconds to 10 minutes, or 40 seconds to 5 minutes, or 40 seconds to 3 minutes, or 40 seconds to 2 minutes, or 40 seconds to 1 minute, or 40 seconds to 50 seconds, or 50 seconds to 20 minutes, or 50 seconds to 10 minutes, or 50 seconds to 5 minutes, or 50 seconds to 3 minutes, or 20 seconds to 2 minutes, or 20 seconds to 1 minute, or 20 seconds to 50 seconds, or 20 seconds to 40 seconds, or 20 seconds to 30 seconds.

[0035] In one embodiment, or in combination with any other embodiment, the temperature is 200°C to 310°C, or 200°C to 300°C, or 200°C to 290°C, or 200°C to 280°C, or 200°C to 270°C, or 200°C to 260°C, or 200°C to 250°C, or 200°C to 240°C, or 200°C to 230°C, or 200°C to 220°C, or 200°C to 210°C, or 210°C to 310°C, or 210°C to 300℃, or 210℃ to 290℃, or 210℃ to 280℃, or 210℃ to 270℃, or 210℃ to 260℃, or 210℃ to 250℃, or 210℃ to 240℃, or 210℃ to 230℃, or 210℃ to 220℃, or 220℃ to 310℃, or 220℃ to 300℃, or 220℃ to 290℃, or 220℃ to 280℃, or 220℃ to 270℃, or 220℃ to 260℃, or 220 °C to 250°C, or 220°C to 240°C, or 220°C to 230°C, or 240°C to 310°C, or 240°C to 300°C, or 240°C to 290°C, or 240°C to 280°C, or 240°C to 270°C, or 240°C to 260°C, or 240°C to 250°C, or 250°C to 310°C, or 250°C to 300°C, or 250°C to 290°C, or 250°C to 280°C, or 250°C to 270°C, or 2 50°C to 260°C, or 260°C to 310°C, or 260°C to 300°C, or 260°C to 290°C, or 260°C to 280°C, or 260°C to 270°C, or 270°C to 310°C, or 270°C to 300°C, or 270°C to 290°C, or 270°C to 280°C, or 280°C to 310°C, or 280°C to 300°C, or 280°C to 290°C, or 290°C to 310°C, or 290°C to 300°C.

[0036] In one embodiment, or in combination with any other embodiment, the Mw after heating is at least 5%, or at least 10%, or at least 15%, or at least 20%, or at least 30%, or at least 40%, or at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90%, or between 5% and 90%, or between 5% and 80%, or 5% to 70%, or 5% to 60%, or 5% to 50%, or 5% to 40%, or 5% to 30%, or 5% to 20%, or 5% to 15%, or 5% to 10%, or 10% to 90%, or 10% to 80%, or 10% to 70%, or 10% to 60%, or 10% to 50%, or 10% to 40%, or 10% to 30%, or 10% to 20%, or 10% to 15%, or 5% to 90%, or or 5% to 80%, or 5% to 70%, or 5% to 60%, or 15% to 50%, or 15% to 40%, or 15% to 30%, or 15% to 20%, or 20% to 90%, or 20% to 80%, or 20% to 70%, or 20% to 60%, or 20% to 50%, or 20% to 40%, or 20% to 30%, or 30% to 90%, or 30% to 80%, or 30% to 70%, or 3 Reduce by 0% to 60%, or 30% to 50%, or 30% to 40%, or 40% to 90%, or 40% to 80%, or 40% to 70%, or 40% to 60%, or 40% to 50%, or 50% to 90%, or 50% to 80%, or 50% to 70%, or 50% to 60%, or 60% to 90%, or 60% to 80%, or 60% to 70%, or 70% to 90%, or 70% to 80%. [Example]

[0037] Abbreviation CA is cellulose acetate, CAB is cellulose acetate butyrate, Ex is example (plural), TA is triacetin, Benzoflex 50 is Eastman Benzoflex 50, PEG400 is Dow Carbowax PEG400, PEG4000 is polyethylene glycol having an average molecular weight of 4000 Da, MFR is melt flow rate, wt% is weight percent, Mw is weight average molecular weight, Mn is number average molecular weight, DE is diatomaceous earth, DA is Daltons, Redtn is reduction, °C is degrees Celsius, GPC is gel permeation chromatography, rpm is revolutions per minute, and DS is degree of substitution.

[0038] Common Protocols Materials: Cellulose acetate with a DS of 2.4-2.6 and Mw of 75,000-120,000 (Eastman CA398-30) was used as the CA resin. Eastman CAB 381-20 was used as the cellulose mixed ester resin (Mn 70,000). Plasticizers were TA, Benzoflex 50, or Dow Carbowax PEG400 added at 10-20 wt%. Calcined kaolin was Burgess Optiwhite P (Burgess Pigment Company). Calcined DE used was Imerys Celite 577. [Table 1]

[0039] Compounded pellets: An 18 mm Leistritz twin-screw extruder equipped with a single-hole die was used to extrude pellets, which were then subsequently used for film extrusion. These pellets were made from a raw material consisting of CA resin powder, plasticizer (PEG 400, Benzoflex 50, or triacetin), and optional stabilizers. Any additives, except for the plasticizer, were added to the base powder and dry-blended to produce a free-flowing powder, which was then added to a Coperion twin-screw weight loss feeder. The plasticizer was fed into zone 2 via a liquid injection unit with a Witte gear pump, a Hardy 4060 controller, and an injector with a 0.020-inch bore. Typical barrel temperatures ranged from 90°C to approximately 225°C at the die. The die temperature was approximately 200-240°C. The screw speed varied from 300 to 468 rpm. The compounded strand was passed through a water bath and pelletized using a ConAir pelletizer.

[0040] Compression Molded Film: Pellets were pre-dried in an oven at 70°C for approximately 8 hours. A film was pressed from the dried pellets on a heated press with the top and bottom platens preheated to 425°F (218°C) for a total of 4 minutes. The pre-dried pellets were applied to the center of a 4-inch square, 10-mil thick frame between the top and bottom layers of aluminum foil, all 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 material, then pressed at 12,000 PHI for 1 minute, ramped to a higher pressure over approximately 30 seconds, and finally held at 20,000 PHI for 1.5 minutes (pounds of ram force).

[0041] Extruded Film: Film was produced using a 1.5-inch Killion single-screw extruder equipped with a Maddock mixer screw. Pellets were loaded into a hopper and passed through the barrel, where the Maddock screw moved the material toward the die. The barrel (containing the screw) was heated in three zones, and the pellets melted as they passed through the screw along a very narrow gap, allowing for high shear and highly dispersive mixing. As the extruder approached the die, a homogeneous polymer mixture was formed. The mixture was forced through the die by the screw, where extrusion occurred. As the film exited the die, a flat molten film formed and solidified on a temperature-controlled polished chrome roll (commonly known as a roll stack). Barrel temperatures typically ranged from 190°C to 240°C with a die temperature of 230°C to 240°C. After extrusion, the film solidified upon cooling, and samples were intermittently removed to determine film thickness. When the extruder was producing the appropriate film thickness, the film was attached to a receiving roller and carefully wound until the final roll was completed.

[0042] Gel permeation chromatography (GPC): CE molecular weight values ​​are calculated as the polystyrene equivalent molecular weight of the test sample dissolved in tetrahydrofuran. Samples are separated using an Agilent Series 1260 liquid chromatography system and detected by refractive index. The mobile phase is tetrahydrofuran stabilized with BHT. Standards are monodisperse polystyrenes ranging in molecular weight from 4,000,000 to 580 daltons.

[0043] Melt Flow Rate: The MFR value of CE is measured using an Instron semi-automatic melt flow tester at 200°C using a 2.16 kg load. The sample is dried at 60°C for 8 hours and then loaded into the instrument. The volume of material extruded from the instrument in a certain time is measured by piston displacement to determine the melt volume rate (MVR). The extrudate is then weighed and the MFR is calculated as grams per 10 minutes.

[0044] I. Blending and Film Extrusion of CA-398-30 with Triacetin and Calcined Kaolin Pellets were compounded as described from the compositions in Table 2, and films were extruded from the compounded pellets at a nominal thickness of 30 mils. The addition of calcined kaolin (Optiwhite P) to Formulation 2 caused the extruded film to become too brittle to take up on a roll. GPC analysis showed that resin Mw and Mn were lower in compounded pellets containing 5 wt.% calcined kaolin. Mw and Mn were further reduced after film extrusion. The reduction in Mw and Mn for CA-398-30 was calculated based on initial Mw and Mn equal to 116,605 and 35,062 Da, respectively. [Table 2]

[0045] II. Formulation of CA-398-30 with Polyethylene Glycol and Calcined Kaolin Pellets were compounded as described from the compositions in Table 3 and films were made using compression molding. The MFR of the pellets was measured. GPC analysis showed that the resin Mw and Mn were lower in compounded pellets containing 5 wt% calcined kaolin. Mw and Mn were further reduced after compression molding and melting under pressure to measure the MFR. [Table 3]

[0046] III. Formulation of CA-398-30 with Polyethylene Glycol and Calcined Kaolin or Calcined DE Pellets were compounded as described from the compositions in Table 4. GPC analysis showed that resin Mw and Mn were lower in compounded pellets containing 5 wt% calcined kaolin. Mw and Mn were further reduced when the pellets were reformulated in a twin-screw extruder. [Table 4]

[0047] Calcined kaolin (5% or 10% by weight) or calcined DE (10% by weight) was blended with plasticized CA-398-30. The calcined kaolin or calcined DE and CA-398-30 powders were sieved together twice to disperse the minerals before adding the plasticizer. The complete blend was dried at 70°C for 16 hours before pressing. Films were pressed as described, and the molding conditions were as detailed in Table 5. The CA used in this example has an Mn of 32,605 kDa. [Table 5]

[0048] IV. Formulation of CA-398-30 with Polyethylene Glycol and Calcined Kaolin Pellets were compounded as described from the compositions in Table 6. GPC analysis showed that the resin Mw and Mn were lower in compounded pellets containing 5 wt% calcined kaolin. [Table 6]

[0049] V.CAB is blended with calcined kaolin Eastman CAB-381-20 was blended with 5% Optiwhite P calcined kaolin at a constant screw speed (468 rpm) at different temperatures ranging from 200°C to 240°C. GPC showed that calcined kaolin was effective in reducing the Mw of CAB-381-20 (Table 7). The reduction in Mw and Mn of CA-381-20 was calculated based on an initial Mw and Mn equal to 145,000 and 44,000 Da, respectively. [Table 7]

[0050] VI. Formulating CA-398-30 and PEG 400 without calcined kaolin CA-398-30 was compounded at different screw speeds and temperatures without calcined kaolin as a control, but the Mw did not decrease in the absence of calcined kaolin (Table 8). [Table 8]

[0051] VII. CA-394-60S is blended with plasticizer and calcined kaolin at low temperature (samples 29-32) Pellets were compounded from Formulation Examples 10, 11, 14, and 15. The dry ingredients were placed in a bag and blended to a free-flowing powder. The plasticizer was fed to Zone 2 via a liquid injection unit with a (Witte) gear pump, a Hardy 4060 controller, and an injector with a 0.020-inch bore. The compounded strand was passed through a water bath and pelletized (using a ConAir pelletizer). The extrusion temperature was 200°C. The molecular weight of the pellets was measured by GPC as described above and is reported in Table 9 below. With the addition of 3-5% calcined kaolin, no significant molecular weight loss was observed when the formulations were processed at 200°C. [Table 9]

[0052] VIII. Reformulation at a higher temperature (ingredients 33-40) As described in Section VII, Table 9, the pellets produced as Samples 29-32 were reprocessed at higher extrusion temperatures using an Xplore microcompounder. For each run, 8 g of compounded pellets were fed and mixed at a specific temperature (220°C or 240°C) for a specific residence time (1 minute or 3 minutes), as described in Table 10. The molecular weight of the pellets was measured by GPC as described above and reported in Table 10 below. The % reduction in Mn and Mw was calculated for Samples 29-32. The results showed that calcined kaolin was effective in reducing molecular weight at 220°C and 240°C. Increasing the extrusion temperature, increasing the extrusion time, and increasing the calcined kaolin content all resulted in a higher degree of chain scission in the CA. [Table 10]

[0053] IX. Melt flow rate of compounded materials The MFR of the pellets produced in Sections I, IV, V, and VI was measured at 220°C and 5 kg (ASTM D1238) and the results are recorded in Table 11. Samples that did not flow are listed as having an MFR equal to 0.00. [Table 11]

Claims

1. 1. A composition comprising: (i) a cellulose ester; (ii) a plasticizer; and (iii) a mineral particle composition; When the mineral particle composition is formulated into an aqueous suspension, the aqueous suspension exhibits a pH of less than 6; the plasticizer is present at 0 to 30 wt. %; the mineral particle composition is present at 0.1 to 40 wt. %; each based on the total weight of the cellulose ester composition.

2. 10. The composition of claim 1, wherein the mineral particle composition comprises calcined kaolin, acid zeolite, bentonite, smectite, montmorillonite, iron (II) oxide, sphalerite, pyrite, calcined diatomaceous earth, or a combination thereof.

3. The composition of claim 1 , wherein the mineral particle composition comprises calcined kaolin or calcined diatomaceous earth.

4. The composition of any one of claims 1 to 3, wherein the mineral particle composition is present at 0.1 to 20% by weight.

5. The composition of any one of claims 1 to 4, wherein the plasticizer is present at 0.1 to 30% by weight.

6. The composition of any one of claims 1 to 5, wherein the cellulose ester is cellulose acetate, cellulose acetate propionate, cellulose acetate butyrate, or a combination thereof.

7. The composition of claim 6 wherein the cellulose ester is cellulose acetate.

8. The composition of claim 7, wherein the plasticizer is present at 5 to 30% by weight.

9. The composition of any one of claims 1 to 6, wherein the cellulose ester is cellulose acetate propionate or cellulose acetate butyrate.

10. The composition of claim 9, wherein the plasticizer is present at 0.1 to 10% by weight.

11. The composition of claim 9, wherein the composition is free of plasticizers.

12. The hydroxyl substituents of the cellulose ester ("DS ＯＨ 12. The composition according to claim 1, wherein the average degree of substitution of 2-(2-methyl-2-propanol)-2-propanol is from 0.5 to 0.

9.

13. 13. The composition of any one of claims 1 to 12, wherein the weight average molecular weight loss is less than 5% when the composition is extruded at a die temperature of 200°C with a residence time of 1 minute, and wherein the weight average molecular weight loss is greater than 5% when the composition is extruded at a die temperature of 220°C with a residence time of 1 minute.

14. The composition of any one of claims 1 to 13 in the form of pellets or powder.

15. 1. A process for reducing the weight average molecular weight (“Mw”) of a cellulose ester, comprising: （１） (i) the cellulose ester; (ii) a mineral particle composition; and heating a composition comprising: When the mineral particle composition is formulated into an aqueous suspension, the aqueous suspension comprises: exhibiting a pH of less than 6 at a temperature of at least 200°C; The process wherein the Mw after heating is reduced by at least 5%.

16. 16. The process of claim 15, wherein the heating is carried out in an extruder or melt press.

17. 17. The process of claim 16, wherein the heating is carried out for a time period of from 1 minute to 10 minutes.

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