Cellulose ester polymer composition with low coefficient of friction

Abstract

The present invention provides a cellulose ester composition comprising a cellulose ester that, after modification, exhibits a reduced coefficient of friction compared to an unmodified composition while substantially maintaining its physical properties such as heat deflection temperature (HDT) and flexural modulus.

Description

Technical Field

[0001] The present invention is generally in the field of polymer science. In particular, the present invention relates to certain cellulose ester polymer compositions having a low coefficient of friction. Background Art

[0002] Cellulose ester polymers, especially mixed ester polymers, such as cellulose acetate propionate (CAP) polymers, can be used to make a variety of molded plastic articles. Cellulose esters are derived from cellulose, are bio-based, and can be obtained from renewable resources such as cotton linter, wood pulp, corn fiber, other agricultural resources, and bacterial cellulose. Commercially available cellulose esters for thermoformed articles usually contain large amounts of plasticizers to facilitate processing and impart sufficient toughness to the molded article.

[0003] CAP polymers tend to have a moderate to high coefficient of friction (COF). A COF that is too high may make it difficult or impossible to use in certain applications. Manipulating the tribological behavior of a polymer, such as by incorporating additives to change the coefficient of friction, may result in a correspondingly large reduction in the physical properties of the base resin or a compromise in performance.

[0004] Construction toys (i.e., toy building blocks) are an example of molded plastic articles in which the coefficient of friction is an important characteristic because it determines the effort required by a person to assemble and separate the toy building blocks. Therefore, there is a need for improved polymer compositions based on cellulose esters (e.g., CAP) having a reduced coefficient of friction without compromising other desirable qualities of the polymer composition or articles made therefrom. Summary of the invention

[0005] It has been found that the friction of bio-based cellulose mixed ester (e.g., CAP) polymers is generally too high to achieve the repeated interaction between similar materials required for many applications, resulting in high forces required to connect and / or separate articles, excessive wear of the polymers due to repeated use, and / or the possibility of bonding between polymers (e.g., friction bonding). Depending on the specific application requirements, existing materials for such applications may not be satisfactory or may have limitations or disadvantages, such as lack of transparency or containing substances of current or future concern. It would also be beneficial to provide suitable materials with sustainable attributes (e.g., bio-based). Existing unmodified cellulose polymers, although bio-based, may also have certain disadvantages, such as not having sufficient toughness or sufficient friction properties to be suitable for certain applications.

[0006] The present invention provides a method for reducing the friction of cellulose ester (e.g., CAP) polymers by incorporating various novel additive combinations. In embodiments, the reduction in coefficient of friction is achieved by incorporating additives including waxes and / or organosilicone, while a good balance of other properties (e.g., toughness and stiffness) is achieved by incorporating certain other additives (e.g., impact modifiers). In addition, certain embodiments also maintain transparency while improving certain properties (e.g., impact toughness) and reducing friction performance.

[0007] The friction-modified cellulose ester (e.g., CAP) polymer has increased ductility and exhibits tunable friction properties comparable to traditional engineering polymers (e.g., acrylonitrile-butadiene-styrene polymer (ABS) or polycarbonate), capable of exhibiting similar friction responses (static, dynamic friction coefficients) over a wide range of contact pressures and component geometries. However, it should be noted that the physical properties (e.g., toughness and modulus) after modification are maintained compared to ABS. In addition, some embodiments provide a method of maintaining transparency in addition to maintaining toughness / stiffness.

[0008] A modified cellulose ester composition is disclosed which is particularly suitable for making injection molded toy building blocks made from bio-based materials having a desired combination of physical and mechanical properties, such as a satisfactory coefficient of friction and toughness. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Embodiments of the present invention are described herein with reference to the following drawings, in which:

[0010] Figure 1 It is a three-dimensional image of a traditional box-shaped toy building block.

[0011] Figure 2 A bottom view of a traditional box-shaped toy building block. DETAILED DESCRIPTION

[0012] In a first aspect, a cellulose ester composition is provided, comprising at least one cellulose ester; at least one impact modifier; at least one friction additive selected from waxes and silicones; and optionally one or more plasticizers. In an embodiment, the heat deformation temperature (HDT) of the cellulose ester composition exceeds 85°C. Unless otherwise expressly stated herein, the HDT is measured at a stress level of 0.455 MPa according to ASTM D648 after conditioning at 70°C for 4 hours. It has been discovered that a cellulose ester composition having a high HDT and good toughness and friction properties can be provided (as more fully described herein).

[0013] In one embodiment, the plasticizer is present in an amount that does not significantly reduce the HDT of the cellulose ester composition compared to a similar composition without the plasticizer. In embodiments, the change (e.g., decrease) in HDT due to the inclusion of the plasticizer does not exceed 10%, or 5%, or 2%.

[0014] In one embodiment, a cellulose ester composition is described that does not contain a plasticizer, but contains 1 wt%-30 wt%, or 1 wt%-15 wt%, or 2 wt%-10 wt%, or 10 wt%-30 wt%, or 15 wt%-30 wt% of an impact modifier based on the total weight of the cellulose ester composition, and has a HDT value greater than 85°C and a notched Izod impact strength value greater than 80 J / m.

[0015] In another embodiment, a cellulose ester composition is provided that is free of plasticizers but is melt-processable. In an embodiment, the melt-processable cellulose ester composition contains 1 wt%-30 wt%, or 1 wt%-15 wt%, or 2 wt%-10 wt%, or 10 wt%-30 wt%, or 15 wt%-30 wt% of an impact modifier based on the total weight of the cellulose ester composition, and has a HDT value greater than 85°C, a notched Izod impact strength value greater than 80 J / m, and a spiral flow value measured at 240°C of at least 15 inches.

[0016] In another embodiment, the melt-processable cellulose ester composition contains 2 wt% to 15 wt% of an impact modifier, based on the total weight of the cellulose ester composition, and has a HDT value greater than 85°C, a notched Izod impact strength value greater than 80 J / m, and a viscosity at 240°C and 400 rad / s of less than 10,000P.

[0017] In another embodiment, a cellulose ester composition is provided having an overall DS / AGU ranging from about 2 to about 2.99, a DS / AGU of acetyl ranging from about 0 to about 2.2, and the remaining ester groups comprising propionyl, butyryl, or a combination thereof.

[0018] In one embodiment, a melt-processable cellulose ester composition is described, which contains up to 15 wt% plasticizer, or up to 10 wt% plasticizer; 1 wt%-30 wt%, or 1 wt%-15 wt%, or 2 wt%-10 wt% impact modifier; and its HDT value is greater than 85°C and the Izod notched impact strength value is greater than 80 J / m.

[0019] In another embodiment, a melt-processible cellulose ester composition is described, which contains up to 15 wt% plasticizer or up to 10 wt% plasticizer based on the total weight of the cellulose ester composition; 1 wt%-30 wt%, or 1 wt%-15 wt%, or 2 wt%-10 wt% impact modifier based on the total weight of the cellulose ester composition; and has an HDT value greater than 85°C, an Izod notched impact strength value greater than 80 J / m, and a spiral flow value measured at 240°C of at least 15 inches.

[0020] In another embodiment, a melt-processable cellulose ester composition is described, which contains up to 15 wt% plasticizer or up to 10 wt% plasticizer based on the total weight of the cellulose ester composition; 1 wt%-30 wt%, or 1 wt%-15 wt%, or 2 wt%-10 wt% impact modifier based on the total weight of the cellulose ester composition; and has a HDT value greater than 85°C, a notched Izod impact strength value greater than 80 J / m, and a viscosity of less than 10000P at 240°C and 400 rad / s.

[0021] In other embodiments, the above-described melt-processable cellulose ester composition optionally contains some plasticizer. In embodiments, the plasticizer is present in an amount that does not significantly reduce the HDT of the cellulose ester composition compared to a similar composition without the plasticizer. In embodiments, the change (e.g., reduction) in HDT due to the inclusion of the plasticizer does not exceed 10%, or 5%, or 2%.

[0022] In one embodiment, a cellulose ester composition is provided, comprising at least one cellulose ester, at least one impact modifier, and optionally at least one plasticizer. In one embodiment, the cellulose ester is CAP, and the composition contains 0 wt% to 5 wt%, 0 wt% to 2 wt%, 0 wt% to less than 2 wt%, or 0 wt% to 1 wt% of the plasticizer. In one embodiment, the cellulose ester is CAP and does not contain a plasticizer.

[0023] In another embodiment, a cellulose ester composition is provided, comprising at least one cellulose ester, at least one impact modifier, and at least one plasticizer. In one embodiment, the cellulose ester is cellulose acetate (CA), and it contains 1 wt%-15 wt% of the plasticizer. In an embodiment, the cellulose ester is CA, and the composition contains 1 wt%-10 wt%, or 1 wt%-less than 10 wt%, or 1 wt%-9 wt% of the plasticizer.

[0024] In one aspect, a cellulose ester composition is provided, comprising:

[0025] (a) at least one cellulose ester;

[0026] (b) at least one impact modifier in an amount ranging from about 1 weight percent to about 30 weight percent;

[0027] (c) at least one friction additive selected from waxes and silicones in an amount ranging from about 0.1 wt % to about 12 wt %; and

[0028] (d) Optionally, one or more plasticizers in an amount ranging from 0 weight percent to about 30 weight percent, in each case the weight percent being based on the total weight of the cellulose ester composition.

[0029] In an embodiment, a cellulose ester composition is provided, comprising 67 wt % to 99 wt % of at least one cellulose ester, 1 wt % to 30 wt % of at least one impact modifier, 0.1 wt % to 5 wt % of at least one friction additive, and 0 wt % to 3 wt % of at least one plasticizer, based on the total weight of the composition, wherein the cellulose ester is selected from one or more of cellulose propionate (CP), cellulose butyrate (CB), cellulose acetate propionate (CAP), cellulose acetate butyrate (CAB), cellulose propionate butyrate (CPB), cellulose tripropionate (CTP), or cellulose tributyrate (CTB); wherein the impact modifier is an acrylic core-shell impact modifier; and wherein the composition has an HDT value greater than 85° C., and an Izod notched impact strength value measured at 23° C. according to ASTM D256 after conditioning a 3.2 mm thick test bar at 23° C. and 50% RH (relative humidity) for 48 hours greater than 80 J / m.

[0030] In another aspect, the cellulose ester composition further comprises a polymerized aliphatic polyester ("PAP"). In an embodiment, the PAP is a polymerized aliphatic polyester comprising residues of one or more C2 to C4 alkane diols and residues of one or more C4 to C8 alkyl dicarboxylic acids, or comprising ring-opened lactone residues. In an embodiment, the PAP comprises residues of C2 to C4 alkane diols and residues of C4 to C6 alkyl dicarboxylic acids. In an embodiment, the PAP comprises residues of ethylene glycol or 1,4-butanediol and residues of succinic acid, glutaric acid and / or adipic acid. In an embodiment, the PAP comprises residues of ethylene glycol or 1,4-butanediol and residues of succinic acid. In an embodiment, the PAP is selected from polybutylene succinate or polyethylene succinate. In an embodiment, the PAP is selected from polybutylene adipate or polyethylene adipate. In an embodiment, the PAP is polybutylene succinate (PBS). In another embodiment, the aliphatic polyester comprises ring-opened residues of lactones (cyclic esters) such as caprolactone. In an embodiment, the PAP may be a copolymer, for example containing residues of succinic acid and adipic acid. In an embodiment, the number average molecular weight (Mn) of the PAP is greater than 2000, or 3000 or more, or 5000 or more, or 7000 or more, or 8000 or more, or 9000 or more, or 9500 or more, or 10000 or more. In an embodiment, the number average molecular weight (Mn) of the PAP is in the range of 5000 to 20000, or 8000 to 20000, or 8000 to 15000, or 9000 to 12000. The molecular weight (and Mn) may be determined using gel permeation chromatography (GPC) with a differential refractive index detector and polystyrene standards using a dichloromethane solvent. In one embodiment, the PAP is polybutylene succinate and has an Mn ranging from 5,000 to 20,000; or from 10,000 to 20,000; or from 15,000 to 20,000.

[0031] In an embodiment, the PAP may be any polybutylene succinate material. In an embodiment, the PAP may be selected from PBS random copolymers obtained from succinic acid or succinic acid, 1,4-butanediol and other dicarboxylic acids or alkyl glycols such as adipic acid, glutaric acid, succinic acid with substituted side groups, suberic acid, 1,3-propylene glycol and other substituted glycols. Examples of polybutylene succinate materials include, but are not limited to, polybutylene succinate-co-butylene adipate (PBSA), polybutylene succinate-co-butylene terephthalate, polybutylene succinate-co-propylene succinate, polybutylene succinate-co-butylene methyl succinate, polybutylene succinate-co-butylene dimethyl succinate, polybutylene succinate-co-butylene phenyl succinate, and blends of polybutylene succinate containing polybutylene adipate, polyethylene succinate, and / or polyethylene adipate. In one embodiment, the PAP is polybutylene succinate (PBS).

[0032] In certain embodiments, the MFR (melt flow rate) of the PAP measured at 190° C. under a 2.16 kg load according to ASTM test method D1238 is less than 30, or less than 25, or less than 20, or less than 15, or less than 10, or less than 6, or about 5 or less. In embodiments, the MFR of the PAP is at least 0.5, or 1, or 2.

[0033] In an embodiment, the MFR (190° C., 2.16 kg) of the PAP is in the range of 0.5-30, or 0.5-25, or 0.5-20, or 0.5-15, or 0.5-10, or 0.5-6, or 0.5-5. In an embodiment, the elongation at break of the PAP is 100% or more, or 150% or more, or 200% or more, or 250% or more. In one embodiment, the cellulose ester composition contains at least one PAP having an MFR (190° C., 2.16 kg) of 10 or less and an elongation at break of 100% or more. In certain embodiments, the amount of PAP in the cellulose ester composition is from 0.5 wt % to 40 wt %, or 1 wt % to 35 wt %, or 1 wt % to 30 wt %, or 1 wt % to 25 wt %, or 1 wt % to 20 wt %, or 1 wt % to 15 wt %, or 1 wt % to 10 wt %, or 1 wt % to 8 wt %, or 2 wt % to 30 wt %, or 2 wt % to 20 wt %, or 2 wt % to 10 wt %, or 2 wt % to 8 wt %, or 2.5 wt % to 30 wt %, or 2.5 wt % to 25 wt %, or 2.5 wt % to 20 wt %, or 2.5 wt % to 15 wt %, or 2.5 wt % to 10 wt %, or 2.5 ...%. .5wt% to 8wt%, or 3wt% to 30wt%, or 3wt% to 25wt%, or 3wt% to 20wt%, or 3wt% to 15wt%, or 3wt% to 10wt%, or 3wt% to 8wt%, or 4wt% to 30wt%, or 4wt% to 25wt%, or 4wt% to 20wt%, or 4wt% to 15wt%, or 4wt% to 10wt%, or 4wt% to 8wt%, or 5wt% to 30wt%, or 5wt% to 25wt%, or 5wt% to 20wt%, or 5wt% to 15wt%, or 5wt% to 10wt%, or 5wt% to 8wt%, or 7wt% to 18wt%, or 8wt% to 12wt%.In certain embodiments, the composition contains at least one impact modifier in an amount of 1 wt % to 20 wt %, or 1 wt % to 15 wt %, or 1 wt % to 10 wt %, or 1 wt % to 8 wt %, or 2 wt % to 15 wt %, or 2 wt % to 10 wt %, or 2 wt % to 8 wt %, or 3 wt % to 15 wt %, or 3 wt % to 10 wt %, or 3 wt % to 8 wt %, or 4 wt % to 15 wt %, or 4 wt % to 10 wt %, based on the total cellulose ester composition. or 4wt% to 8wt%, and optionally contains at least one monomeric plasticizer in addition to PAP, and the amount of PAP in the cellulose ester composition is 0.5wt% to 40wt%, or 1wt% to 35wt%, or 2wt% to 30wt%, or 2wt% to 20wt%, or 2wt% to 10wt%, or 3wt% to 10wt%, or 3wt% to 8wt%, or 3wt% to 7wt%, or 4wt% to 8wt%; or 4wt% to 7wt%, or 5wt% to 7wt%.

[0034] Cellulose esters

[0035] In an embodiment, the cellulose ester used in the present invention can be any cellulose ester known in the art. The cellulose ester that can be used in the present invention generally comprises repeating units of the following structure:

[0036]

[0037] Where R 1 , R 2 and R 3Independently selected from the group consisting of hydrogen or straight-chain alkanoyl groups having 2 to 10 carbon atoms. For cellulose esters, the substitution level is usually expressed as a degree of substitution (DS), i.e., the average number of non-OH substituents per anhydroglucose unit (AGU). Typically, conventional cellulose contains three hydroxyl groups that can be substituted in each AGU unit; therefore, the value of DS can be between 0 and 3. However, due to the end group contribution, the total degree of substitution of low molecular weight cellulose mixed esters can be slightly higher than 3. Natural cellulose is a large polysaccharide with a degree of polymerization of 250–5000 even after pulping and purification, so the assumption that the maximum DS is 3.0 is approximately correct. However, as the degree of polymerization decreases, such as in low molecular weight cellulose mixed esters, the end groups of the polysaccharide backbone become relatively more significant, resulting in DS that can vary beyond 3.0. Low molecular weight cellulose mixed esters will be discussed in more detail later in this disclosure. Since DS is a statistical average, a value of 1 does not guarantee that each AGU has a single substituent. In some cases, unsubstituted anhydroglucose units may be present, some having two substituents, some having three substituents, and this value is not generally an integer. Total DS is defined as the average number of all substituents per anhydroglucose unit. The degree of substitution of each AGU may also refer to a specific substituent, such as a hydroxyl, acetyl, butyryl or propionyl. In an embodiment, the degree of polymerization of cellulose ester is lower than that of native cellulose. In an 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.

[0038] In an embodiment, the cellulose ester used may be a cellulose triester or a cellulose diester (secondarycellulose ester). Examples of cellulose triesters include, but are not limited to, cellulose triacetate, cellulose tripropionate, or cellulose tributyrate. Examples of cellulose diesters include cellulose acetate, cellulose acetate propionate, and cellulose acetate butyrate. For the purposes of this disclosure, unless otherwise expressly stated, cellulose acetate (CA) includes cellulose acetate and / or cellulose diacetate.

[0039] In one embodiment, the cellulose ester may be selected from cellulose acetate (CA), cellulose propionate (CP), cellulose butyrate (CB), cellulose acetate propionate (CAP), cellulose acetate butyrate (CAB), cellulose propionate butyrate (CPB), cellulose acetate isobutyrate (CAIB), etc., or a combination thereof. Examples of such cellulose esters are described in U.S. Pat. Nos. 1,698,049; 1,683,347; 1,880,808; 1,880,560; 1,984,147, 2,129,052, and 3,617,201, the entire contents of which are incorporated herein by reference to the extent not inconsistent with the statements herein. In one embodiment, the cellulose ester is CAP.

[0040] In one embodiment, the cellulose ester may be selected from cellulose propionate (CP), cellulose butyrate (CB), cellulose acetate propionate (CAP), cellulose acetate butyrate (CAB), cellulose propionate butyrate (CPB), cellulose tripropionate (CTP) or cellulose tributyrate (CTB), but not selected from cellulose acetate (CA).

[0041] In an embodiment, the cellulose ester has at least 2 anhydroglucose rings, and may have at least 50 to a maximum of 5000 anhydroglucose rings. The number of anhydroglucose units per molecule is defined as the degree of polymerization (DP) of the cellulose ester. In an embodiment, the intrinsic viscosity (IV) of the cellulose ester may be from about 0.2 dl / g to about 3.0 dl / g, or from about 0.5 dl / g to about 1.8 dl / g, or from about 1 dl / g to about 1.5 dl / g, as measured at a temperature of 25°C for 0.25g of a sample in a 100ml 60 / 40 weight ratio of phenol / tetrachloroethane solution. Examples of cellulose esters include, but are not limited to, cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate (CAP), cellulose acetate butyrate (CAB), cellulose propionate butyrate, and the like. In an embodiment, the cellulose esters available herein may have a DS / AGU of from about 2 to about 2.99, and the substituted esters may include acetyl, propionyl, and butyryl, or any combination of these. In another embodiment, the total DS / AGU ranges from about 2 to about 2.99, the DS / AGU of acetyl groups ranges from about 0 to 2.2, and the remaining ester groups include propionyl, butyryl, or a combination thereof.

[0042] In another embodiment, the total DS / AGU ranges from about 2 to about 2.99, the DS / AGU of acetyl ranges from about 0 to 1.2, and the remaining ester groups include propionyl, butyryl, or a combination thereof. In another embodiment, the total DS / AGU ranges from about 2 to about 2.99, and the DS / AGU of acetyl ranges from about 0 to 0.5, and the remaining ester groups include propionyl, butyryl, or a combination thereof.

[0043] In certain embodiments, the total percentage of propionyl groups in the cellulose ester by weight, based on the total weight of the cellulose ester polymer, is between 5% and 52%, or between 10% and 52%, or between 15% and 52%, or between 20% and 52%, or between 25% and 52%, or between 30% and 52%, or between 35% and 52%, or between 40% and 52%, or between 45% and 52%, or between 49% and 52%, or between 5% and 50%, or between 10% and 50%, or between 15% and 50%, or between 20% and 50%, or between 25% and 50%, or between 30% and 50%, or between 35% and 50%, or between 40% and 50 ...0%, or between 5% and less than 50%, or between 10% and less than 50%, or between 15% and less than 50%, or between 20% and less than 50%, or between 25% and less than 50%, or between 35% and 50%, or between 40% and 50%, or between 45% and 50%, or between 5% and less than 50%, or between 10% and less than 50%, or between 15% and less than 50%, or between 20% and less than 50%, or between 25% and less than 50%, 30% to less than 50%, or 35% to less than 50%, or 40% to less than 50%, or 45% to less than 50%, or 35% to less than 50%, or 40% to less than 50%, or 45% to less than 50%, or 5% to 38%, or 10% to 38%, or 15% to 38%, or 20% to 38%, or 25% to 38%, or 30% to 38 ...35% to less than 50%, or 35% to less than 50%, or 35% to less than 50%, or 35% to less than 50%, or 35% to less than 50%, or 35% to less than 50%, or 35% to less than 50%, or 35% to less than 50%, or 35% to less than 50%, or 35% to less than 50%, or 35% to less than 50%, or 35% to less than 50 % to 38%, or 5% to 35%, or 5% to 35%, or 10% to 35%, or 15% to 35%, or 20% to 35%, or 25% to 35%, or 30% to 35%, or 5% to 30%, or 10% to 30%, or 15% to 30%, or 20% to 30%, or 25% to 30%, or 5% to 20%, or 10% to 20%.

[0044] In certain embodiments, the total percentage of butyryl groups in the cellulose ester by weight, based on the total weight of the cellulose ester polymer, is between 5% and 57%, or between 10% and 57%, or between 15% and 57%, or between 20% and 57%, or between 25% and 57%, or between 30% and 57%, or between 35% and 57%, or between 40% and 57%, or greater than 40% and 57%, or between 41% and 57%, or between 45% and 57%, or between 50% and 57%, or between 51% and 57%, or between 52% and 57%, or between 53% and 57%, or between 54% and 57%, or between 56% and 57%, or between 58% and 58%, or between 59% and 60%, or between 61% and 61%, or between 62% and 63%, or between 64% and 65%, or between 66% and 67%, or between 68% and 68%, or between 69% and 70%, or between 71% and 71%, or between 72% and 73%, or between 74% and 75%, or between 76% and 77%, or between 78% and 79%, or between 80% and 81%, or between 81% and 81%, or between 82% and 83%, or between 84% and 85%, or between 86% and 87%, or between 88% and 89%, or between 90% and 91%, or between 91% and 92%, or between 93% and 93%, or between 94% and 95%, or between 96% and 97%, or between 98% and 99%, or between 99% and 100%, or between 5% to 55%, or 10% to 55%, or 15% to 55%, or 20% to 55%, or 25% to 55%, or 30% to 55%, or 35% to 55%, or 40% to 55%, or more than 40% to 55%, or 41% to 55%, or 45% to 55%, or 50% to 55%, or 5% to 50%, or 10% to 50%, or 15% to 50%, or 20% to 50%, or 25% to 50 %, or 30% to 50%, or 35% to 50%, or 40% to 50%, or more than 40 to 50%, or 41% to 50%, or 45% to 50%, or 5% to 45%, or 10% to 45%, or 15% to 45%, or 20% to 45%, or 25% to 45%, or 30% to 45%, or 35% to 45%, or 40% to 45%, or more than 40 to 45%, or 41% to 45%, or 5% To 35%, or 10% to 35%, or 15% to 35%, or 20% to 35%, or 25% to 35%, or 30% to 35%, or 5 to less than 32%, or 10% to less than 32%, or 15% to less than 32%, or 20% to less than 32%, or 25% to less than 32%, or 5% to 30%, or 10% to 30%, or 15% to 30%, or 20% to 30%, or 25% to 30%.

[0045] In certain embodiments, the cellulose ester is cellulose propionate butyrate or cellulose acetate propionate butyrate, wherein the combined content of propionate and butyryl groups is between 15% and 55%, or 15% and 50%, or 15% and 45%, or 15% and 40%, or 15% and 35%, or 15% and 30%, or 15% and 25%, or 15% and 20%, or 20% and 55%, or 20% and 50%, or 20% and 45%, or 20% and 40%, or 20% and 35%, or 20% and 30%, or 20% and 25%, or 25% and 55%, or 25% and 25% or 35% to 40%, or 40% to 55%, or 40% to 50%, or 35% to 45%, or 30% to 40%, or 30% to 35%, or 35% to 55%, or 35% to 50%, or 35% to 45%, or 35% to 40%, or 40% to 55%, or 40% to 50%, or 40% to 45%, or 40% to 55%, or 40% to 55%, or 40% to 55%, or 40% to 45%, or 45% to 55%, or 45% to 50%, or 50% to 55%.

[0046] In one embodiment, the cellulose ester is CA. In certain embodiments, the total percentage of acetyl groups in the cellulose ester by weight is between 5% and 45%, or between 10% and 45%, or between 15% and 45%, or between 20% and 45%, or between 25% and 45%, or between 30% and 45%, or between 35% and 45%, or between 40% and 45%, or between 5% and 40%, or between 10% and 40%, or between 15% and 40%, or between 20% and 40%, or between 25% and 40 ... or 30% to 40%, or 35% to 40%, or 5% to 35%, or 10% to 35%, or 15% to 35%, or 20% to 35%, or 25% to 35%, or 30% to 35%, or 5% to 30%, or 10% to 30%, or 15% to 30%, or 20% to 30%, or 25% to 30%, or 5% to 25%, or 10% to 25%, or 15% to 25%, or 20% to 25%.

[0047] In certain embodiments, the total percentage of propionyl groups in the cellulose ester by weight is in the range of 1% to 20%, or 1% to 15%, or 1% to 10%, or 1% to 5%, or 2% to 20%, or 2% to 15%, or 2% to 10%, or 2% to 5%, or 3% to 20%, or 3% to 15%, or 3% to 10%, or 3% to 5%, or 4% to 20%, or 4% to 15%, or 4% to 10%, or 5% to 20%, or 5% to 15%, or 5% to 10%, based on the total weight of the cellulose ester polymer.

[0048] In certain embodiments, the total percentage of butyryl groups in the cellulose ester by weight is in the range of 1% to 20%, or 1% to 15%, or 1% to 10%, or 1% to 5%, or 2% to 20%, or 2% to 15%, or 2% to 10%, or 2% to 5%, or 3% to 20%, or 3% to 15%, or 3% to 10%, or 3% to 5%, or 4% to 20%, or 4% to 15%, or 4% to 10%, or 5% to 20%, or 5% to 15%, or 5% to 10%, based on the total weight of the cellulose ester polymer.

[0049] In embodiments, any of the cellulose esters discussed above may also contain up to 10% residual hydroxyl units, preferably from 0.5% to 5%.

[0050] Cellulose esters can be prepared by any method known in the art. Examples of processes for preparing cellulose esters are taught in Kirk-Othmer's Encyclopedia of Chemical Technology, Fifth Edition, Vol. 5, Wiley-Interscience, New York (2004), pp. 394-444. Cellulose, the starting material for preparing cellulose esters, can be obtained in different grades and sources, such as from cotton linters, softwood pulp, hardwood pulp, corn fiber and other agricultural resources, and bacterial cellulose, among others.

[0051] One method of preparing cellulose esters is to esterify cellulose by mixing cellulose with an appropriate organic acid, anhydride, and catalyst. The cellulose is then converted to a cellulose triester. The esters are then hydrolyzed by adding a water-acid mixture to the cellulose triesters, which can then be filtered to remove any gel particles or fibers. Water is then added to the mixture to precipitate the cellulose ester. The cellulose ester can then be washed with water to remove reaction by-products, followed by dehydration and drying.

[0052] The cellulose triester to be hydrolyzed may have three substituents independently selected from alkanoyl groups having 2 to 10 carbon atoms. Examples of cellulose triesters include cellulose triacetate, cellulose tripropionate and cellulose tributyrate, or mixed triesters of cellulose, such as cellulose acetate propionate and cellulose acetate butyrate. These cellulose esters may be prepared by a variety of methods known to those skilled in the art. For example, cellulose esters may be prepared by heterogeneous acylation of cellulose in a mixture of carboxylic acid and anhydride in the presence of a catalyst (e.g., H2SO4). Cellulose triesters may also be prepared by homogeneous acylation of cellulose dissolved in a suitable solvent (e.g., LiCl / DMAc or LiCl / NMP).

[0053] Those skilled in the art will appreciate that the commercial term cellulose triesters also include cellulose esters that are not fully substituted with acyl groups. For example, cellulose triacetate commercially available from Eastman Chemical Company in Kingsport, Tennessee, USA, typically has a DS of about 2.85 to about 2.99.

[0054] After cellulose is esterified to triester, some of the acyl substituents can be removed by hydrolysis or alcoholysis to obtain cellulose diester. As previously mentioned, the distribution of acyl substituents can be random or non-random, depending on the specific method used. Cellulose diester can also be prepared directly by using a limited amount of acylating agent without hydrolysis. This process is particularly useful when the reaction is carried out in a solvent that dissolves cellulose. All of these methods can produce cellulose esters that can be used in the present invention.

[0055] In one embodiment, the cellulose diesters useful in the present invention have an absolute weight average molecular weight (Mw) of about 5,000 to about 400,000 measured by gel permeation chromatography (GPC) according to ASTM D6474. The following method is used to calculate the absolute weight average molecular weight value (Mw) of CE. The solvent is THF stabilized with a BHT preservative. The instrument for the THF / cellulose ester program consists of the following Agilent 1200 series components: a degasser, an isocratic pump, an autosampler, a column oven, a UV / Vis detector, and a differential refractive index detector. The detection temperature is 30°C and the flow rate is 1.0 ml / min. A sample solution of 25 mg of cellulose ester in 10 ml of THF with a BHT preservative and a 10 μl toluene flow rate marker is prepared. The injection volume is 50 μl. The column group is a Polymer Laboratories 5 μm PLgel, Guard+Mixed C+Oligopore. Detection is performed by refractive index. The calibrants are monodisperse polystyrene standards, Mw=580 to 3220000, from Polymer Laboratories. The general calibration parameters are as follows: PS (K=0.0001280 and a=0.7120) and CE (K=0.00007572 and a=0.8424). The above general calibration parameters are determined by light scattering and viscometer to obtain the correct weight average molecular weight. In another embodiment, the Mw is from about 15000 to about 300000. In another embodiment, the Mw range is from about 10000 to about 250000; from about 15000 to 200000; from about 20000 to about 150000; from about 50000 to about 150000, or from about 70000 to about 120000.

[0056] In an embodiment, the polymer-based resin comprises a cellulose ester having an absolute weight average molecular weight in the range of about 40,000 Da to about 200,000 Da as measured according to ASTM D5296 using tetrahydrofuran as solvent and a flow rate of 1 mL / min. In certain embodiments, the absolute weight average molecular weight of the cellulose ester is in the range of about 50,000 Da to about 200,000 Da, or 50,000 Da to about 170,000 Da, or 50,000 Da to about 120,000 Da, or 50,000 Da to about 90,000 Da, or 60,000 Da to about 200,000 Da, or 60,000 Da to about 170,000 Da, or 60,000 Da to about 120,000 Da, or 60,000 Da to about 90,000 Da, or 90,000 Da to about 170,000 Da, or 90,000 Da to about 120,000 Da, or 120,000 Da to about 200,000 Da, as measured according to ASTM D5296 using tetrahydrofuran as the solvent and a flow rate of 1 mL / min.

[0057] Commercial cellulose diesters can be prepared by an initial acid-catalyzed heterogeneous acylation of cellulose to form cellulose triesters. After obtaining a homogeneous solution of the cellulose triesters in the corresponding carboxylic acids, the cellulose triesters are hydrolyzed until the desired degree of substitution is obtained. After separation, random cellulose diesters are obtained. That is, the relative degree of substitution (RDS) of each hydroxyl group is approximately equal.

[0058] Some examples of cellulose esters that can be used in the present invention can be prepared using techniques known in the art and are available from Eastman Chemical Company, Kingsport, Tennessee, USA, such as Eastman TM Cellulose acetate propionate CAP 482-20, Eastman TM Cellulose acetate propionate CAP 141-20, Eastman TM Cellulose acetate butyrate CAB 381-20, Cellulose acetate butyrate CAB 171-15 and Eastman TM Cellulose acetate CA 398-30.

[0059] In embodiments, the cellulose esters used in the present invention may also contain chemical functional groups and are described herein as derivatized, modified or functionalized cellulose esters. Functionalized cellulose esters may be prepared by reacting the free hydroxyl groups of the cellulose ester with a bifunctional reactant having a linking group for grafting to the cellulose ester and a functional group that provides a new chemical group to the cellulose ester. Examples of such bifunctional reactants include succinic anhydride, which is linked by an ester bond and provides acid functionality; mercaptosilane, which is linked by an alkoxysilane bond and provides mercapto functionality; and isocyanatoethyl methacrylate, which is linked by a urethane bond and provides methacrylate functionality.

[0060] In one embodiment, the functionalized cellulose ester is prepared by reacting the free hydroxyl groups of the cellulose ester with a difunctional reactant which produces a cellulose ester having at least one functional group selected from the group consisting of unsaturation (double bond), carboxylic acid, acetoacetate, acetoacetimide, mercapto, melamine, and a long alkyl chain.

[0061] Bifunctional reactants for preparing cellulose esters containing unsaturated (double bond) functionality are described in U.S. Pat. Nos. 4,839,230, 5,741,901, 5,871,573, 5,981,738, 4,147,603, 4,758,645, and 4,861,629; all of which are incorporated herein by reference to the extent not inconsistent with the statements herein. In one embodiment, the cellulose ester containing unsaturation is prepared by reacting a cellulose ester containing residual hydroxyl groups with an acrylic compound and m-isopropenyl-α,α'-dimethylbenzyl isocyanate. Grafted cellulose esters are urethane-containing products with pendant (meth)acrylate and α-methylstyrene moieties. In another embodiment, the cellulose ester containing unsaturation is prepared by reacting maleic anhydride with a cellulose ester in the presence of an alkaline earth metal or lower alkyl monocarboxylic acid ammonium salt catalyst, and at least one saturated monocarboxylic acid has 2 to 4 carbon atoms. In another embodiment, a cellulose ester containing unsaturation is prepared from the reaction product of (a) at least one cellulosic polymer having isocyanate-reactive hydroxyl functional groups and (b) at least one hydroxyl-reactive poly(α,β vinyl unsaturated)isocyanate.

[0062] Bifunctional reactants for preparing cellulose esters containing carboxylic acid functionality are described in U.S. Pat. Nos. 5,384,163, 5,723,151, and 4,758,645; all of which are incorporated herein by reference to the extent not inconsistent with the statements herein. In one embodiment, the cellulose ester containing carboxylic acid functionality is prepared by reacting a cellulose ester with a monoester or diester of maleic acid or fumaric acid to obtain a cellulose derivative having double bond functionality. In another embodiment, the cellulose ester containing carboxylic acid functionality has a first residue and a second residue, wherein the first residue is a residue of a cyclic dicarboxylic acid anhydride and the second residue is a residue of a lipophilic monocarboxylic acid and / or a residue of a hydrophilic monocarboxylic acid. In yet another embodiment, the cellulose ester containing carboxylic acid functionality is cellulose acetate phthalate, which can be prepared by reacting cellulose acetate with phthalic anhydride.

[0063] Bifunctional reactants for preparing cellulose esters containing acetoacetate functionality are described in U.S. Pat. No. 5,292,877; which is incorporated herein by reference to the extent not inconsistent with the statements herein. In one embodiment, cellulose esters containing acetoacetate functionality are prepared by contacting: (i) cellulose; (ii) diketene, an alkyl acetoacetate, 2,2,6,trimethyl-4H-1,3-dioxin-4-one, or a mixture thereof; and (iii) a solubilizing amount of a solvent system comprising lithium chloride and a carboxamide selected from the group consisting of 1-methyl-2-pyrrolidone, N,N-dimethylacetamide, or a mixture thereof.

[0064] Bifunctional reactants for preparing cellulose esters containing acetoacetimide functionality are described in U.S. Pat. No. 6,369,214, which is incorporated herein by reference to the extent not inconsistent with the statements herein. Cellulose esters containing acetoacetimide functionality are the reaction product of a cellulose ester with at least one acetoacetyl group and an amine-functional compound comprising at least one primary amine.

[0065] Difunctional reactants for preparing cellulose esters containing mercapto functionality are described in U.S. Pat. No. 5,082,914; which is incorporated herein by reference to the extent not inconsistent with the statements herein. In one embodiment, the cellulose ester is grafted with a silicon-containing mercaptan component, which can be commercially available or prepared by procedures known in the art. Examples of silicon-containing mercaptan compounds include, but are not limited to: (3-mercaptopropyl)trimethoxysilane, (3-mercaptopropyl)dimethylmethoxysilane, (3-mercaptopropyl)dimethoxymethylsilane, (3-mercaptopropyl)dimethylchlorosilane, (3-mercaptopropyl)dimethylethoxysilane, (3-mercaptopropyl)diethoxymethylsilane, and (3-mercaptopropyl)triethoxysilane.

[0066] Bifunctional reactants for preparing cellulose esters containing melamine functionality are described in U.S. Pat. No. 5,182,379; which is incorporated herein by reference to the extent not inconsistent with the statements herein. In one embodiment, the cellulose ester containing melamine functionality is prepared by reacting a cellulose ester with a melamine compound to form a grafted cellulose ester having melamine moieties grafted onto a backbone of anhydroglucose rings of the cellulose ester. In one embodiment, the melamine compound is selected from the group consisting of methylol ethers of melamine and aminoplast resins.

[0067] Bifunctional reactants for preparing cellulose esters containing long alkyl chain functionality are described in U.S. Pat. No. 5,750,677; which is incorporated herein by reference to the extent not inconsistent with the statements herein. In one embodiment, the cellulose ester containing long alkyl chain functionality is prepared by reacting cellulose in a carboxamide diluent or a urea-based diluent with an acylating agent using a titanium-containing material. The cellulose ester containing long alkyl chain functionality can be selected from the group consisting of cellulose acetate caproate, cellulose acetate nonanoate, cellulose acetate laurate, cellulose palmitate, cellulose acetate stearate, cellulose nonanoate, cellulose caproate, cellulose caproate propionate, and cellulose nonanoate propionate.

[0068] Impact modifier

[0069] In an embodiment, the impact modifier can be any material that can increase the impact strength of the cellulose ester composition. In one embodiment, the impact modifier can be any polymer material that is classified as an elastomer having a glass transition temperature (Tg) below room temperature. For example, Tg can be measured according to ASTM D3418 using a TA 2100 thermal analysis instrument at a scan rate of 20°C / min. There are several classes of impact modifiers that fit this description.

[0070] In one embodiment, the impact modifier may be selected from the class of materials known as modified polyolefins (or olefin copolymers), in which the olefins are copolymerized with additional monomers that restrict the crystallization of the polymer, increase the number of chains with a Tg below room temperature, and reduce the modulus to below 500 MPa. Examples of modified olefins include ethylene methyl acrylate (EMA) or ethylene glycidyl methacrylate (EGMA) (examples include Elvaloy 4051, Lotader 3410 and Lotader 8900), ethylene butyl acrylate (EBA), ethylene vinyl acetate (EVA) (examples include Levamelt 500, Levamelt 600, Levamelt 700, Levamelt 800, Elvax 40W, Evatane 28-40, Evatane 40-55, Evatane 18-150, Bynel E418 and Bynel 3101), ethylene ethyl acrylate (EEA), ethylene propylene diene monomer based elastomer (EPDM) (examples include Royaltuf 498) and ethylene propylene rubber elastomer (EPR).

[0071] In one embodiment, the impact modifier can be a block copolymer, wherein at least one segment of the chain has a Tg below room temperature, referred to as a soft segment, and at least one segment of the chain has a Tg or Tm above room temperature, referred to as a hard segment. These block copolymers are also commonly referred to as thermoplastic elastomers (TPEs). Examples of such block copolymers include styrenic materials such as polystyrene-butadiene-styrene (SBS), polystyrene-ethylene-butylene-styrene (SEBS) and styrene-isoprene-rubber elastomer (SIS) (examples include Kraton G1657MS, Kraton FG1901 G and Kraton FG1924G); thermoplastic polyurethanes (TPU) (examples include Elastolan 1170Z, Estane 2355, Estane ALR CL87A and Estane ALR 72A); polyester-ether copolymers (examples include Ecdel9966 and Hytrel 3078) or polyamide-ether copolymers (examples include Pebax 5533).

[0072] In one embodiment, the impact modifier can be selected from the class of materials prepared by emulsions known as core-shell impact modifiers. In one embodiment, the impact modifier is a MBS core-shell impact modifier, such as methacrylate-butadiene-styrene, which has a core made of butadiene-styrene copolymer and a shell made of methyl methacrylate-styrene copolymer. In another embodiment, the impact modifier is an acrylic core-shell impact modifier, which has a core made of an acrylic polymer (such as butyl acrylate or styrene butyl acrylate), and a shell made of polymethyl methacrylate or styrene methyl methacrylate copolymer.

[0073] In an embodiment, the MBS impact modifier may comprise a grafted polymer composition comprising 10 wt % to 70 wt % of a butadiene polymer or copolymer and firstly grafts of methyl (meth)acrylate and a crosslinker, secondly grafts of styrene, and thirdly grafts of methyl (meth)acrylate with an optional crosslinker.

[0074] Monomers suitable for polymerization with conjugated dienes (preferably butadiene) may include alkenyl aromatic compounds, and preferably vinyl aromatic compounds, such as styrene, divinylbenzene, α-methylstyrene, vinyltoluene, hydrogenated styrene; lower (CZ-Cu) alkyl acrylates (e.g. ethyl acrylate, n-propyl acrylate, n-butyl acrylate, Z-methylbutyl acrylate, 3-methylbutyl acrylate, pentyl acrylate, n-hexyl acrylate, Z-ethylhexyl acrylate); lower (C2-C12) (meth) alkyl acrylates; acrylonitrile; olefins; etc.; or any combination of the above.

[0075] Suitable crosslinking agents include divinylbenzene; di(meth)acrylates; diacrylates, such as diacrylates of mono-, di- or polyethylene glycol; their (meth)acrylates; divinyl sulfide; divinyl ether; vinyl acrylate; vinyl (meth)acrylate; trivinylbenzene; trimethylolpropane; tri(meth)acrylates; triallyl cyanurate and triallyl isocyanurate.

[0076] In one embodiment, MBS core-shell anti-impact modifier can include the copolymer of butadiene and styrene, and most preferably the terpolymer of butadiene, styrene and divinylbenzene.Although the relative amount of the monomers forming the copolymerization matrix can change, based on the combination of 100 weight portions of butadiene, styrene and divinylbenzene, the butadiene component generally accounts for about 30 weight portions to 100 weight portions, and the styrene component accounts for 0 weight portion to about 70 weight portions, and the divinylbenzene component accounts for 0 weight portion to about 5 weight portions.In one embodiment, the copolymerization matrix can include the butadiene of about 50 weight portions to about 90 weight portions based on the same basis, the styrene of about 10 weight portions to about 50 weight portions and the divinylbenzene of about 0 weight portion to about 5 weight portions, and most preferably, include the butadiene of about 65 weight portions to about 85 weight portions based on the same basis, the styrene of about 15 weight portions to about 35 weight portions and the divinylbenzene of about 0.5 weight portion to about 2.0 weight portions.

[0077] Examples of methacrylate-butadiene-styrene core-shell polymers include, but are not limited to, those described in US 4,446,585, US 5,534,594, and US 6,331580. MBS core-shell impact modifiers are available from Kane Ace B564 from Kaneka, Clearstrength from Arkema, Metablen C and Metablen E from Mitsubishi Chemical, Paraloid from Dow, and Visiomer from Evonik.

[0078] In one embodiment, the core-shell impact modifier is an acrylic impact modifier, which comprises about 25 wt % to 95 wt % of a first elastomeric phase, which is polymerized from a monomer system, wherein the monomer system comprises about 75 wt % to 99.8 wt % of (C1 to C6) alkyl acrylate, 0.1 wt % to 5 wt % of a crosslinking monomer and 0.1 wt % to 5 wt % of a graft-linking monomer; and about 75 wt % to 5 wt % of a final rigid thermoplastic phase, which does not contain epoxy groups polymerized in the presence of the elastomeric phase.

[0079] Examples of useful acrylates are methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, etc. In some embodiments, the acrylates are n-butyl acrylate and ethyl acrylate.

[0080] The grafting monomer is defined as a polyethylenically unsaturated monomer having both highly reactive double bonds and low reactive double bonds, so that the highly reactive double bonds tend to polymerize during the first stage monomer polymerization process, while the remaining double bonds polymerize during the next stage polymerization process, thereby grafting the first stage polymer with the second stage polymer. In some embodiments, the grafting monomer is allyl methacrylate, allyl acrylate, and diallyl maleate. In one embodiment, there is 0.05% to 3% of the grafting monomer based on the first stage monomer system. It is also preferred that there is a crosslinking monomer, which is generally about 0.05% to 3% by weight based on the first stage monomer system, and is defined as a polyethylenically unsaturated monomer having at least two double bonds of approximately equal reactivity so as to cause crosslinking in the first stage polymerization. Examples of typical crosslinking monomers are 1,3-butene diacrylate, 1,3-butene dimethacrylate, divinylbenzene, and the like.

[0081] "Epoxy functionality" refers to epoxy units pendant from a final-stage polymer. In some embodiments, epoxy functionality is incorporated into the final-stage polymer by using epoxy-containing monomers (e.g., glycidyl acrylate or glycidyl methacrylate) in the final-stage monomer mix.

[0082] Examples of acrylic core-shell polymers include, but are not limited to, those described in patents US 3,448,173, US 3,655,825, and US 3,853,968. Examples of suitable acrylic impact modifiers are Kane Ace ECO 100 and M570 from Kaneka, Durastrength from Arkema, Elvaloy and Elvaloy HP from DuPont, Metablen W from Mitsubishi Chemical, and Paraloid from Dow.

[0083] In one class of this embodiment, the impact modifier is an ABS core-shell impact modifier having a core made of butadiene-styrene copolymer and a shell made of acrylonitrile-styrene copolymer. Examples of ABS core-shell impact modifiers include Blendex from Galata Chemicals and Elix from Elix Polymers.

[0084] In one class of this embodiment, the impact modifier is a silicone acrylic core-shell impact modifier having a core made of silicone acrylic rubber and a shell made of PMMA copolymer or methyl methacrylate-styrene copolymer. Examples of silicone acrylic core-shell impact modifiers include Metablen S from Mitsubishi Chemical Company.

[0085] In one embodiment, the impact modifier has a neutral acidity. It is believed that this will help prevent degradation of the cellulose ester during melt processing of the composition.

[0086] In one embodiment, the impact modifier can be a non-reactive impact modifier or a reactive impact modifier, or a combination of both.The impact modifier used can also improve the mechanical and physical properties of the cellulose ester composition.

[0087] In one embodiment, in the case of using a non-reactive impact modifier, the impact modifier contains a first polymer segment that is more chemically or physically compatible with cellulose ester than another polymer segment. In one embodiment, the first segment contains polar functional groups that provide compatibility with cellulose ester, including but not limited to polar functional groups such as ethers, esters, amides, alcohols, amines, ketones, and acetals. Compatibility is defined by the preferential interaction of the first polymer segment with the cellulose ester polymer relative to the second segment, and can represent molecular or microscale interactions. The first segment can be composed of the following oligomers or polymers: cellulose ester; cellulose ether; polyoxyalkylenes, such as polyoxyethylene, polyoxypropylene, polyoxybutylene; polyglycols, such as polyethylene glycol, polypropylene glycol, polybutylene glycol; polyesters, such as polycaprolactone, polylactic acid, aliphatic polyesters, aliphatic-aromatic copolyesters; polyacrylates and polymethacrylates; polyacetals; polyvinyl pyrrolidone; polyethylene vinyl acetate; polyvinyl acetate; and polyvinyl alcohol. In one embodiment, the first segment is polyethylene vinyl acetate; polyoxyethylene or polyvinyl alcohol.

[0088] In an embodiment, the second segment can be a saturated or unsaturated hydrocarbon group, or contain both saturated and unsaturated hydrocarbon groups. The second segment can be an oligomer or a polymer. In one embodiment, the second segment of the non-reactive impact modifier is selected from the group consisting of polyolefins, polydienes, polyaromatics, and copolymers. An example of a polyaromatic second segment is polystyrene. An example of a copolymer second segment is a styrene / butadiene copolymer.

[0089] The first segment and the second segment of the non-reactive impact modifier can be a diblock, triblock, branched or comb-like structure. The weight average molecular weight (Mw) of the non-reactive impact modifier can be about 300 to about 20,000, or about 500 to about 10,000, or about 1,000 to about 5,000. The segment ratio of the non-reactive impact modifier can be about 15% to about 85% of the polar first segment to about 15% to about 85% of the non-polar second segment.

[0090] Examples of non-reactive impact modifiers include, but are not limited to, ethoxylated alcohols, ethoxylated alkylphenols, ethoxylated fatty acids, polyethylene vinyl acetate, block polymers of propylene oxide and ethylene oxide, ethylene / propylene terpolymers, functionalized polyolefins, polyglycerol esters, polysaccharide esters, and polysorbates. Examples of ethoxylated alcohols are C 11 -C 15 Secondary alcohol ethoxylates, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, C 12 -C 14 Natural straight chain alcohol. 11 -C 15 Secondary alcohol ethoxylates are available as Dow 15S. Polyoxyethylene cetyl ether and polyoxyethylene stearyl ether can be obtained from ICI Surfactants A series of products were obtained. 12 -C 14 Natural straight chain alcohols can be obtained from HoechstCelanese Examples of ethoxylated alkylphenols include octylphenoxypoly(ethyleneoxy)ethanol and nonylphenoxypoly(ethyleneoxy)ethanol. Octylphenoxypoly(ethyleneoxy)ethanol is available as Rhodia CA series products, and nonylphenoxy poly(ethyleneoxy)ethanol can be obtained as Rhodia's IgepalCO series products or Dow Chemical Company's NP. Ethoxylated fatty acids may include polyethylene glycol monostearate or monolaurate, which may be obtained from Henkel's Block polymers of propylene oxide and ethylene oxide can be obtained from BASF's Polyglycerol esters can be obtained from Stepan Polysaccharide esters can be obtained from Henkel A series of products are available, all of which are alkyl polysaccharides. Polysorbates can be obtained from ICI A series of products were obtained.

[0091] In another embodiment, non-reactive impact modifiers can be synthesized in situ in the cellulose ester composition by reacting compounds compatible with cellulose esters. These compounds can be, for example, telechelic oligomers, which are defined as prepolymers capable of further polymerization or other reactions through their reactive end groups. In one embodiment, these in situ impact modifiers can have a higher weight average molecular weight (Mw), from about 10,000 to about 1,000,000.

[0092] In another embodiment, the impact modifier can be reactive. The reactive impact modifier can include a polymer or oligomer compatible with one component of the composition, and a functional group that can react with another component of the composition. In an embodiment, there are two types of reactive impact modifiers that can be used. The first reactive impact modifier has a hydrocarbon chain that is compatible with cellulose esters, and also has a functional group that can react with cellulose esters. Such functional groups include, but are not limited to, carboxylic acids, anhydrides, acyl chlorides, epoxides, and isocyanates. Specific examples of this type of reactive impact modifier include, but are not limited to: long chain fatty acids, such as stearic acid (octadecanoic acid); long chain fatty acid chlorides, such as stearic acid chloride (octadecanoyl chloride); long chain fatty acid anhydrides, such as stearic anhydride (octadecanoic anhydride); epoxidized oils and fatty esters; styrene maleic anhydride copolymers; maleic anhydride grafted polypropylene; copolymers of maleic anhydride with olefins and / or acrylates, such as terpolymers of ethylene, acrylates and maleic anhydride; and copolymers of glycidyl methacrylate with olefins and / or acrylates, such as terpolymers of ethylene, acrylates and glycidyl methacrylate.

[0093] Reactive impact modifiers are available in the form of Sartomer / Cray Valley 3000 Styrene Maleic Anhydride Copolymer, Eastman from Eastman Chemical Company Maleic anhydride grafted polypropylene, Westlake Chemical E-43 maleic anhydride grafted polypropylene, Arkema MAH8200 Random terpolymer of ethylene, acrylic acid ester and maleic anhydride, GMA AX 8900 random terpolymer of ethylene, acrylic acid esters and glycidyl methacrylate, and GMA AX 8840 is a random terpolymer of ethylene, acrylic acid ester and glycidyl methacrylate.

[0094] Reactive polyolefin impact modifiers may include Lotader, Fusabond, Elvaloy PTW, Lotryl, Elvaloy AC, InterLoy.

[0095] The reactive impact modifier of the second type has a polar chain compatible with cellulose esters and also has a functional group that can react with cellulose esters. Examples of this type of reactive impact modifier include cellulose esters or polyethylene glycols with olefin or thiol functional groups. Reactive polyethylene glycol impact modifiers with olefin functional groups include but are not limited to polyethylene glycol allyl ether and polyethylene glycol acrylate. An example of reactive polyethylene glycol impact modifiers with thiol functional groups includes polyethylene glycol mercaptan. An example of reactive cellulose ester impact modifiers includes thioglycolate cellulose.

[0096] In an embodiment, the amount of impact modifier in the cellulose ester composition may be in the range of about 1 wt % to about 15 wt %, or about 2 wt % to about 10 wt %, or about 4 wt % to about 10 wt %, or about 4 wt % to about 8 wt %, or about 5 wt % to about 10 wt %, based on the weight of the cellulose ester composition.

[0097] Friction Additives

[0098] In embodiments, the friction additive may be any material capable of reducing the static and / or dynamic coefficient of friction of the cellulose ester composition as compared to the base resin (i.e., the composition without the friction additive). In embodiments, the friction additive may reduce the static and / or dynamic coefficient of friction of the cellulose ester composition while maintaining or not significantly reducing the physical properties of the base resin.

[0099] In an embodiment, one or more friction additives may be selected from a variety of waxes and silicones. Waxes that can be used in cellulose ester compositions may include higher alkanes and lipids, which are lipophilic plastic solids at room temperature (i.e., 23° C.). Natural waxes are found in plants and animals, and are also found in petroleum products. In one embodiment, the wax is a mixture of saturated alkanes, cycloalkanes, and alkyl- and cycloalkanes-substituted aromatic compounds. In another embodiment, the wax is a montan wax extracted from certain coal and lignite sources. In another embodiment, the wax may be rice bran wax (RBW), such as RBW derived from crude rice bran, such as RBW Vita additive (from Clariant). In another embodiment, the wax may be a polyolefin wax. In some embodiments, naturally occurring waxes such as beeswax, which is primarily myricyl palmitate, cetyl palmitate, lanolin, carnuba wax may be used.

[0100] In an embodiment, the one or more friction additives may include one or more siloxanes. Siloxanes are compounds containing Si-O-Si bonds. Examples include compounds having the structures H(OSiH2)nOH and (OSiH2)n. In other embodiments, the siloxane is a silicone or polysiloxane having the structure (-RSi-O-SiR-), where R is an organic group, such as an alkyl or aryl group. Examples of such polysiloxanes are polydimethylsiloxane or "PDMS" and polydiphenylsiloxane.

[0101] Commercially available examples of such waxes and silicones include Genioplast S, a granular silicone rubber formulation from Wacker Chemie AG; Tegomer H-Si (e.g., H-Si 6441P), a polyester-modified silicone from Evonik Industries AG; Dowsil® from Dow Chemical Company; TM Si powder resin modifier (eg, DowSil 4-7081); and Loxiol P (eg, P861), which is a polyol ester available from Emery Oleochemicals GmbH.

[0102] In embodiments, the amount of wax and / or silicone used as a friction additive component may be from about 0.1% to about 15% by weight of the cellulose ester composition, or from about 0.1% to about 12% by weight, or from about 0.1% to about 10% by weight, or from about 0.1% to about 8% by weight, or from about 0.1% to about 6% by weight, or from about 0.1% to about 5% by weight, or from about 0.1% to about 4% by weight, or from about 0.1% to about 3% by weight, or from about 0.1% to about 2% by weight, or from about 0.1% to about 1% by weight, or from about 0.2% to about 5% by weight, or from about 0.2% to about 4% by weight, or from about 0.2% to about 3% by weight. %, or about 0.2 wt % to about 2 wt %, or about 0.2 wt % to about 1 wt %, or about 0.3 wt % to about 5 wt %, or about 0.3 wt % to about 4 wt %, or about 0.3 wt % to about 3 wt %, or about 0.3 wt % to about 2 wt %, or about 0.3 wt % to about 1.5 wt %, or about 0.4 wt % to about 2 wt %, or about 0.4 wt % to about 1.5 wt %, or about 0.5 wt % to about 5 wt %, or about 0.5 wt % to about 4 wt %, or about 0.5 wt % to about 3 wt %, or about 0.5 wt % to about 2 wt %, or about 0.5 wt % to about 1.5 wt %, or about 0.5 wt % to about 5 wt %, or about 0.5 wt % to about 4 wt %, or about 0.5 wt % to about 3 wt %, or about 0.5 wt % to about 2 wt %, or about 0.5 wt % to about 1.5 wt %, or about 0.5 wt % to about 1 wt %.

[0103] In an embodiment, the friction additive component comprises one or more siloxanes in an amount of about 0.1% to about 10% by weight of the cellulose ester composition, or about 0.1% to about 8% by weight, or about 0.1% to about 6% by weight, or about 0.1% to about 5% by weight, or about 0.1% to about 4% by weight, or about 0.1% to about 3% by weight, or about 0.1% to about 2% by weight, or about 0.1% to about 1% by weight, or about 0.2% to about 5% by weight, or about 0.2% to about 4% by weight, or about 0.2% to about 3% by weight, or about 0.2% to about 2% by weight, Or about 0.2 wt % to about 1 wt %, or about 0.3 wt % to about 5 wt %, or about 0.3 wt % to about 4 wt %, or about 0.3 wt % to about 3 wt %, or about 0.3 wt % to about 2 wt %, or about 0.3 wt % to about 1.5 wt %, or about 0.4 wt % to about 2 wt %, or about 0.4 wt % to about 1.5 wt %, or about 0.5 wt % to about 5 wt %, or about 0.5 wt % to about 4 wt %, or about 0.5 wt % to about 3 wt %, or about 0.5 wt % to about 2 wt %, or about 0.5 wt % to about 1.5 wt %, or about 0.5 wt % to about 1 wt %.

[0104] Plasticizers

[0105] In one embodiment, the composition may contain a plasticizer. The plasticizer used may be any plasticizer known in the art that is capable of reducing the glass transition temperature and / or melt viscosity of the cellulose ester to improve melt processing characteristics. The plasticizer may be any plasticizer suitable for use with cellulose esters. The plasticizer content should be lower than the normal (or typical) plasticizer content of the cellulose ester; so that the composition has a higher Tg (or HDT), good toughness and good fluidity than a fully plasticized cellulose ester composition. In an embodiment, the plasticizer is present in an amount that does not significantly reduce the Tg (or HDT) of the cellulose ester composition compared to a similar composition without the plasticizer. In an embodiment, the change (e.g., decrease) in Tg (or HDT) due to the inclusion of the plasticizer will not exceed 20%, or 15%, or 10%, or 5%, or 2%.

[0106] The structure of the plasticizer can be monomeric or polymeric. In one embodiment, the plasticizer is at least one selected from the group consisting of aromatic phosphate plasticizers, alkyl phosphate plasticizers, dialkyl ether diester plasticizers, tricarboxylic acid ester plasticizers, polymer polyester plasticizers, polyethylene glycol diester plasticizers, polyester resin plasticizers, aromatic diester plasticizers, aromatic triester plasticizers, aliphatic diester plasticizers, carbonate plasticizers, epoxidized ester plasticizers, epoxidized oil plasticizers, benzoate plasticizers, polyol benzoate plasticizers, adipate plasticizers, phthalate plasticizers, glycolate plasticizers, citrate plasticizers, hydroxyl functional plasticizers or solid non-crystalline resin plasticizers.

[0107] In one embodiment, the plasticizer can be selected from at least one of the following: triphenyl phosphate, tricresyl phosphate, toluene diphenyl phosphate, octyl diphenyl phosphate, diphenyl biphenyl phosphate, trioctyl phosphate, tributyl phosphate, diethyl phthalate, dimethoxyethyl phthalate, dimethyl phthalate, dioctyl phthalate, dibutyl phthalate, di-2-ethylhexyl phthalate, butyl benzyl phthalate, dibenzyl phthalate, butyl phthaloyl glycolate, ethyl phthaloyl glycolate, methyl phthaloyl glycolate, triethyl citrate, tri-n-butyl citrate, acetyl triethyl citrate, acetyl tri-n-butyl citrate, acetyl tri-n-(2-ethylhexyl) citrate, diethylene glycol dibenzoate, dipropylene glycol dibenzoate, or triethylene glycol dibenzoate.

[0108] In another embodiment, the plasticizer can be selected from at least one of the following: esters, including: (i) acid residues, which include one or more residues of the following: phthalic acid, adipic acid, trimellitic acid, succinic acid, benzoic acid, azelaic acid, terephthalic acid, isophthalic acid, butyric acid, glutaric acid, citric acid or phosphoric acid; and (ii) alcohol residues, which include residues of one or more of aliphatic alcohols, alicyclic alcohols or aromatic alcohols containing up to about 20 carbon atoms.

[0109] In another embodiment, the plasticizer can be selected from at least one of the following: esters, including: (i) at least one acid residue selected from the group consisting of phthalic acid, adipic acid, trimellitic acid, succinic acid, benzoic acid, azelaic acid, terephthalic acid, isophthalic acid, butyric acid, glutaric acid, citric acid and phosphoric acid; and (ii) at least one alcohol residue selected from the group consisting of aliphatic alcohols, alicyclic alcohols and aromatic alcohols containing up to about 20 carbon atoms.

[0110] In another embodiment, the plasticizer may include an alcohol residue, wherein the alcohol residue is at least one selected from the group consisting of stearyl alcohol, lauryl alcohol, phenol, benzyl alcohol, hydroquinone, catechol, resorcinol, ethylene glycol, neopentyl glycol, 1,4-cyclohexanedimethanol, and diethylene glycol.

[0111] In another embodiment, the plasticizer may be selected from at least one of benzoates, phthalates, phosphates, arylene-bis(diaryl phosphates), and isophthalates. In another embodiment, the plasticizer includes diethylene glycol dibenzoate, abbreviated herein as "DEGDB".

[0112] In another embodiment, the plasticizer may be selected from at least one of the following: an aliphatic polyester comprising C 2-10 Diacid residues such as malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, and sebacic acid; and C 2-10 Diol residue.

[0113] In another embodiment, the plasticizer may include a diol residue, which may be the following C2-C 10 The residue of at least one of the diols: ethylene glycol, diethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, 1,5-pentylene glycol, triethylene glycol, tetraethylene glycol.

[0114] In another embodiment, plasticizer can comprise polyglycol, for example polyethylene glycol, polypropylene glycol and polybutylene glycol.These scope can be from low molecular weight dimer and trimer to high molecular weight oligomer and polymer.In one embodiment, the molecular weight range of polyglycol can be about 200 to about 2000.

[0115] In another embodiment, the plasticizer includes at least one of the following: R296 plasticizer, 804 plasticizer, SHP (sorbitol hexapropionate), XPP (xylitol pentapropionate), XPA (xylitol pentaacetate), GPP (glucose pentaacetate), GPA (glucose pentapropionate), APP (arabinitol pentapropionate).

[0116] In another embodiment, the plasticizer comprises one or more of the following: A) about 5 wt % to about 95 wt % of C2-C 12 A carbohydrate organic ester, wherein the carbohydrate comprises from about 1 to about 3 monosaccharide units; and B) from about 5 wt % to about 95 wt % of C2-C12 Polyol esters wherein the polyol is derived from a C5 or C6 carbohydrate. In one embodiment, the polyol ester does not comprise or contains one or more polyol acetates.

[0117] In another embodiment, the plasticizer comprises at least one carbohydrate ester, and the carbohydrate portion of the carbohydrate ester is derived from one or more compounds selected from the group consisting of glucose, galactose, mannose, xylose, arabinose, lactose, fructose, sorbose, sucrose, cellobiose, cellotriose and raffinose.

[0118] In another embodiment, the plasticizer comprises at least one carbohydrate ester, and the carbohydrate portion of the carbohydrate ester comprises one or more of α-glucose pentaacetate, β-glucose pentaacetate, α-glucose pentapropionate, β-glucose pentapropionate, α-glucose pentabutyrate, and β-glucose pentabutyrate.

[0119] In another embodiment, the plasticizer comprises at least one carbohydrate ester, and the carbohydrate portion of the carbohydrate ester comprises an α-anomer, a β-anomer, or a mixture thereof.

[0120] In another embodiment, the plasticizer may be selected from at least one of propylene glycol dibenzoate, glyceryl tribenzoate, diethylene glycol dibenzoate, triethylene glycol dibenzoate, dipropylene glycol dibenzoate, and polyethylene glycol dibenzoate.

[0121] In another embodiment, the plasticizer can be a solid non-crystalline resin. These resins can contain a certain amount of aromatic or polar functional groups and can reduce the melt viscosity of cellulose esters. In one embodiment, the plasticizer can be a solid non-crystalline compound (resin), such as rosin; hydrogenated rosin; stabilized rosin, and their monofunctional alcohol esters or polyol esters; modified rosin, including but not limited to maleic acid and phenol modified rosin and esters thereof; terpene resin; phenol modified terpene resin; coumarin-indene resin; phenolic resin; alkylphenol-acetylene resin; and phenol-formaldehyde resin.

[0122] In another embodiment, the plasticizer is at least one plasticizer selected from the group consisting of triacetin, trimethyl phosphate, triethyl phosphate, tributyl phosphate, triphenyl phosphate, triethyl citrate, acetyl trimethyl citrate, acetyl triethyl citrate, acetyl tributyl citrate, o-acetyl tributyl citrate, dibutyl phthalate, diaryl phthalate, diethyl phthalate, dimethyl phthalate, di-2-methoxyethyl phthalate, dioctyl phthalate, dioctyl adipate, dibutyl tartrate, ethyl o-benzoylbenzoate, ethyl Ethyl phthaloyl glycolate, ethyl methyl phthaloyl glycolate, N-ethyl toluenesulfonamide, methyl o-cresol toluenesulfonate, aromatic diols, substituted aromatic diols, aromatic ethers, tripropionin, triphenin, polycaprolactone, glycerol, glycerol esters, diacetyl glycerol, acetic benzoic acid glyceryl, polyethylene glycol, polyethylene glycol esters, polyethylene glycol diesters, di-2-ethylhexyl polyethylene glycol esters, triethylene glycol di-2-ethylhexanoate, glycerol esters, diethylene glycol, polypropylene glycol, polyethylene glycol diglycidyl ether, dimethyl sulfoxide, N-methylpyrrolidone, C1-C20 di Carboxylic acid esters, dimethyl adipate, dibutyl maleate, dioctyl maleate, resorcinol monoacetate, catechol, catechol esters, phenols, epoxidized soybean oil, castor oil, linseed oil, epoxidized linseed oil, other vegetable oils, other seed oils, difunctional glycidyl ethers based on polyethylene glycol, γ-valerolactone, alkyl phosphates, aryl phosphates, phospholipids, eugenol, cinnamyl alcohol, camphor, methoxyhydroxyacetophenone, vanillin, ethyl vanillin, 2-phenoxyethanol, glycol ethers, glycol esters, glycol ester ethers, polyethylene glycol ethers, polyethylene glycol esters, glycol ethers, propylene glycol Glycol ethers, ethylene glycol esters, propylene glycol esters, polypropylene glycol esters, 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, diethylene glycol dibenzoate, dipropylene glycol dibenzoate, triethylene glycol dibenzoate, butylated benzyl alcohol, butylated hydroxyanisole, sorbitol, xylitol, ethylenediamine, piperidine, piperazine, hexamethylenediamine, triazine, triazole, pyrrole, and any combination thereof.

[0123] In an embodiment, the amount of plasticizer in the cellulose ester composition may be in the range of 0 wt % to about 15 wt % based on the weight of the cellulose ester composition. In one embodiment, the amount may be up to about 15 wt % based on the weight of the cellulose ester composition. In another embodiment, the amount may be up to about 10 wt % based on the weight of the cellulose ester composition. In another embodiment, the amount may be up to about 5 wt % based on the weight of the cellulose ester composition, or up to about 3 wt % based on the weight of the cellulose ester composition, or less than 2 wt % based on the weight of the cellulose ester composition. In an embodiment, the cellulose ester composition comprises a cellulose ester that is CA and contains a plasticizer as described herein, for example, the amount of plasticizer included is in the range of 1 to 15 wt%, or 1 wt% to 10 wt%, or 1 wt% to 8 wt%, or 2 wt% to 15 wt%, or 2 wt% to 10 wt%, or 2 wt% to 8 wt%, or 2 wt% to 6 wt%, or 2 wt% to 5 wt%, or 3 wt% to 15 wt%, or 3 wt% to 10 wt%, or 3 wt% to 8 wt%, or 3 wt% to 6 wt%, based on the total weight of the composition.

[0124] In another embodiment, the cellulose ester composition contains no plasticizer.In one embodiment, the cellulose ester composition comprises a cellulose ester that is a CAP and contains no plasticizer.In one embodiment, the cellulose ester composition comprises a cellulose ester that is a CAB and contains no plasticizer.

[0125] Specific embodiments of cellulose ester composition

[0126] In certain embodiments, the cellulose ester composition comprises 75 wt% to 98 wt% or about 80 wt% to 98 wt% of at least one cellulose ester, in one embodiment CAP; 1 wt% to 15 wt% or 1 wt% to 10 wt% of at least one impact modifier, in one embodiment an acrylic core-shell impact modifier; and 0.1 wt% to 10 wt% or 0.2 wt% to 5 wt% of at least one friction additive. In an embodiment, the friction additive comprises or is a silicone friction additive.

[0127] In certain embodiments, the cellulose ester composition comprises 55 wt% to 98 wt%, or about 77 wt% to 98 wt% of at least one cellulose ester, in one embodiment CAP; 1 wt% to 15 wt%, or 1 wt% to 10 wt% of at least one impact modifier, in one embodiment an acrylic core-shell impact modifier; 1 wt% to 30 wt%, or 1 wt% to 20 wt%, or 1 wt% to 10 wt% of at least one PAP, in one embodiment a PBS having an MFR (190°C, 2.16 kg) of less than 25 and an elongation at break of 100% or greater; and 0.1 wt% to 10 wt%, or 0.2 wt% to 5 wt% of at least one friction additive, such as a silicone friction additive. In an embodiment, CAP contains greater than 10 wt%, or greater than 20 wt%, or greater than 30 wt%, or greater than 40 wt%, or greater than 45 wt% of propionyl.

[0128] In one embodiment, the cellulose ester composition is transparent, with a light transmittance of at least 70%, or at least 75%, or at least 80%, or at least 85%, or at least 90% measured according to ASTM D1003 using a 3.2 mm plaque after injection molding at a barrel set point of 249° C. and a residence time of 5 minutes. In certain embodiments, the light transmittance of the polymer-based resin measured according to ASTM D1003 using a 3.2 mm plaque after injection molding at a barrel set point of 249° C. and a residence time of 5 minutes is in the range of 70% to 95%, or 75% to 95%, or 80% to 95%, or 85% to 95%, or 90% to 95%, or 70% to 90%, or 75% to 90%, or 80% to 90%, or 85% to 90%. In a class of this embodiment, the cellulose ester composition comprising a PAP (e.g., PBS), an impact modifier (e.g., an acrylic core-shell impact modifier), and a friction additive has a haze of less than 10%. In embodiments, the cellulose ester composition comprising PAP, an impact modifier, and a friction additive has a haze of less than 8%, or less than 6%, or less than 5%.

[0129] In another embodiment, the refractive index (RI) of the PAP and the impact modifier are both close enough to that of the cellulose ester to provide a composition with high light transmittance and low haze. In one embodiment, the RI of the PAP, the impact modifier, and the friction additive are all close to the RI of the cellulose ester (about 1.46-1.48) to provide a transparent composition. In an embodiment, the PAP, the impact modifier, and the friction additive each have a refractive index RI (second component)-RI (first component) (e.g., RI of CE-RI of PBS) difference of about 0.006 to about -0.0006 relative to the cellulose ester component, and the light transmittance of the blend is at least 75%, and the haze is 10% or less, more preferably 5% or less.

[0130] In an embodiment, the amount of PAP (e.g., PBS) in the cellulose ester composition can be in a range of about 0.5 wt % to about 40 wt %, or about 1 wt % to about 35 wt %, or 2 wt % to 30 wt %, or 2 wt % to 20 wt %, or 2 wt % to 10 wt %, or about 2.5 wt % to about 30 wt %, or about 5 wt % to about 25 wt %, or about 5 wt % to about 20 wt %, or about 5 wt % to about 15 wt %, or about 5 wt % to about 10 wt %, or about 10 wt % to about 30 wt %, or about 10 wt % to about 25 wt %, or about 10 wt % to about 20 wt %, or about 10 wt % to about 15 wt %, or greater than 10 wt % to about 30 wt %, or greater than 10 wt % to about 25 wt %, or greater than 10 wt % to about 20 wt %, or greater than 10 wt % to about 15 wt %, based on the weight of the cellulose ester composition. In an embodiment, the composition contains, in addition to at least one impact modifier, at least one friction additive and optionally at least one monomeric plasticizer, at least one PAP in an amount of 0.5 wt % to 40 wt %, or 1 wt % to 35 wt %, or 2 wt % to 30 wt %, or 2 wt % to 20 wt %, or 2 wt % to 10 wt %, or 3 wt % to 10 wt %, or 3 wt % to 8 wt %, or 3 wt % to 7 wt %, or 4 wt % to 8 wt %; or 4 wt % to 7 wt %, based on the total cellulose ester composition.

[0131] In another embodiment, the cellulose ester composition further comprises at least one additional polymeric component as a blend (with the cellulose ester) in an amount of 5% to 95% by weight based on the total cellulose ester composition. Suitable examples of additional polymeric components include, but are not limited to, nylon; polyester; polyamide; polystyrene; other cellulose esters, cellulose ethers; polystyrene copolymers; styrene acrylonitrile copolymers; polyolefins; polyurethanes; acrylonitrile butadiene styrene copolymers; polymethyl methacrylate; acrylic acid copolymers; polyetherimides; polyphenylene oxides; polyvinyl chloride; polyphenylene sulfide; polyphenylene sulfide / sulfone; polyester carbonate; polycarbonate; polysulfone; polylactic acid; polysulfone ether; and polyether ketones of aromatic dihydroxy compounds; or mixtures of any of the foregoing polymers. The blend can be prepared by conventional processing techniques known in the art, such as melt blending or solution blending. In certain embodiments, the total amount of additional polymeric compounds (excluding PAP) is less than 25% by weight, or less than 20% by weight, or less than 15% by weight, or less than 10% by weight, or less than 5% by weight, or does not exist, based on the total weight of the cellulose ester composition.

[0132] In another embodiment, the composition is melt processable. Melt processability generally refers to the ability to heat process a material at a temperature below its degradation temperature to obtain uniform pellets or plastic products. For example, the composition can be melt extruded on a Werner & Pflerderer 30 mm twin screw extruder at a throughput of 35 lbs / hour, a screw speed of 250 rpm, and a barrel temperature of 240°C. Injection molding on a Toyo 110 injection molding machine with a barrel temperature of 240°C and a mold temperature of 160°F resulted in minimal molecular weight or discoloration.

[0133] In one embodiment, a melt-processible cellulose ester composition is provided, comprising from 1 wt% to 30 wt%, or from 1 wt% to 15 wt%, or from 2 wt% to 10 wt% of an impact modifier and being free of plasticizer, the cellulose ester composition having a HDT value greater than 85°C, a notched Izod impact strength value greater than 80 J / m (measured according to ASTM D256 at 23°C for a 3.2 mm thick bar), and a spiral flow value of at least 15 inches at 240°C when measured using the procedures described herein. In one embodiment, the cellulose ester composition has a Tg value greater than 120°C as measured at 20°C / min according to ASTM D3418. Unless otherwise stated, notched Izod impact strength testing was performed on molded bars after notching a 3.2 mm thick bar at 23°C according to ASTM method D256 after conditioning at 23°C and 50% RH for 48 hours.

[0134] In another embodiment, the composition has a melt viscosity of 10000P or less at 240°C and 400 rad / s, as measured by a plate-plate melt rheometer, such as a Rheodynamic Analyzer (RDA II) with 25 mm diameter parallel plates, 1 mm gap, and 10% strain, measured according to ASTM D4440 using a frequency sweep from 1 rad / s to 400 rad / s.

[0135] In one embodiment, the melt-processable cellulose ester composition comprises 1 wt% to 30 wt% or 1 wt% to 15 wt% of an impact modifier, 0 wt% to 15 wt% of a plasticizer, and a Tg greater than 90°C. In another embodiment, the melt-processable cellulose ester composition comprises 1 wt% to 30 wt% or 1 wt% to 15 wt% of an impact modifier, 0 wt% to 10 wt% of a plasticizer, and a Tg greater than 100°C. In yet another embodiment, the melt-processable cellulose ester composition comprises 1 wt% to 10 wt% of an impact modifier, 0 wt% to 10 wt% of a plasticizer, and a Tg greater than 100°C. In another embodiment, the melt-processable cellulose ester composition comprises 1 wt% to 10 wt% of an impact modifier, 0 wt% to 5 wt% of a plasticizer, and a Tg greater than 115°C.

[0136] In one embodiment, the melt-processable cellulose ester composition comprises 1 wt% to 30 wt% or 1 wt% to 15 wt% of an impact modifier, 1 wt% to 20 wt% or 1 wt% to 15 wt% of a PAP, 0 wt% to 15 wt% of a plasticizer, and a Tg greater than 90°C. In another embodiment, the melt-processable cellulose ester composition comprises 1 wt% to 30 wt% or 1 wt% to 15 wt% of an impact modifier, 1 wt% to 20 wt% or 1 wt% to 15 wt% of a PAP, 0 wt% to 10 wt% of a plasticizer, and a Tg greater than 100°C. In yet another embodiment, the melt-processable cellulose ester composition comprises 1 wt% to 10 wt% of an impact modifier, 1 wt% to 15 wt% of a PAP, 0 wt% to 10 wt% of a plasticizer, and a Tg greater than 100°C. In another embodiment, the melt processable cellulose ester composition comprises 1 wt% to 10 wt% impact modifier, 1 wt% to 10 wt% PAP, 0 wt% to 5 wt% plasticizer, and has a Tg greater than 115°C.

[0137] In another embodiment, the cellulose ester composition has a Tg or HDT similar to that of the base cellulose ester polymer, only a few degrees Celsius lower (e.g., less than 5°C, or less than 2°C), incorporates an impact modifier and contains no plasticizer. The impact properties of these compositions may also exceed 80 J / m (Izod notched impact strength at 23°C).

[0138] In an embodiment, the cellulose ester composition has a HDT greater than 80° C., or greater than 85° C., measured at 1.82 MPa using a 3.2 mm thick test bar at 70° C. for 4 hours according to ASTM D648. In certain embodiments, the polymer-based resin has a HDT of at least 85° C., at least 90° C., or at least 95° C. at 0.455 MPa. In certain embodiments, the HDT of the cellulose ester composition is in the range of 85°C to 140°C, 85°C to 130°C, 85°C to 120°C, 85°C to 110°C, 85°C to 105°C, 85°C to 100°C, 85°C to 95°C, 90°C to 140°C, 90°C to 130°C, 90°C to 120°C, 90°C to 110°C, 90°C to 105°C, 90°C to 100°C, 95°C to 140°C, 95°C to 130°C, 95°C to 120°C, 95°C to 110°C, 95°C to 105°C, 95°C to 100°C.

[0139] In an embodiment, the polymer-based resin has a notched Izod impact strength of at least 80 J / m, or at least 90 J / m, or to 100 J / m, or at least 110 J / m, or at least 120 J / m, or at least 130 J / m, or at least 140 J / m, or at least 150 J / m, or at least 160 J / m, or at least 170 J / m, or at least 180 J / m, or at least 190 J / m, or at least 200 J / m, as measured according to ASTM D256 using a 3.2 mm thick test bar that has been conditioned at 23° C., 50% relative humidity for 48 hours. In certain embodiments, the polymer-based resin has a notched Izod impact strength of about 80 J / m to about 500 J / m, about 80 J / m to about 400 J / m, about 80 J / m to about 300 J / m, about 80 J / m to about 200 J / m, about 100 J / m to about 500 J / m, about 100 J / m to about 400 J / m, about 100 J / m to about 300 J / m, about 100 J / m to about 200 J / m, about 120 J / m to about 500 J / m, about 120 J / m to about 400 J / m, about 120 J / m to about 300 J / m, about 120 J / m to about 200 J / m, about 150 J / m to about 500 J / m, about 150 J / m to about 400 J / m, about 150 J / m to about 300 J / m, about J / m to about 200 J / m, about 150 J / m to about 200 J / m, about 170 J / m to about 500 J / m, about 170 J / m to about 400 J / m, about 170 J / m to about 300 J / m, about 170 J / m to about 200 J / m, about 180 J / m to about 500 J / m, about 180 J / m to about 400 J / m, about 180 J / m to about 300 J / m, about 180 J / m to about 200 J / m, about 190 J / m to about 500 J / m, about 190 J / m to about 400 J / m, about 190 J / m to about 300 J / m, about 190 J / m to about 200 J / m, about 200 J / m to about 500 J / m, about 200 J / m to about 400 J / m, or about 200 J / m to about 300 J / m, as described in accordance with ASTM D 1475, or ASTM D 1475. D256 is measured using a 3.2 mm thick test bar that has been conditioned at 23°C and 50% relative humidity for 48 hours.

[0140] In an embodiment, the flexural modulus of the polymer-based resin is greater than 1800 MPa, as measured according to ASTM D790 using a 3.2 mm thick test bar that has been placed at 23° C., 50% relative humidity for 48 hours. In certain embodiments, the flexural modulus of the polymer-based resin is at least 1900 MPa, at least 2000 MPa, at least 2100 MPa, at least 2200 MPa, at least 2300 MPa, or at least 2400 MPa, as measured according to ASTM D790 using a 3.2 mm thick test bar that has been placed at 23° C., 50% relative humidity for 48 hours. In certain embodiments, the flexural modulus of the polymer-based resin is in the range of about 1800 MPa to about 3500 MPa, about 1900 MPa to about 3500 MPa, about 2000 MPa to about 3500 MPa, about 2100 MPa to about 3500 MPa, about 2200 MPa to about 3500 MPa, about 2300 MPa to about 3500 MPa, about 2400 MPa to about 3500 MPa, or about 2500 MPa to about 3500 MPa, as measured according to ASTM D790 using a 3.2 mm thick test bar that has been conditioned at 23° C., 50% relative humidity for 48 hours. In certain embodiments, the flexural modulus of the polymer-based resin is in the range of about 1900 MPa to about 2500 MPa, about 1900 MPa to about 2800 MPa, or about 1900 MPa to about 3000 MPa, as measured according to ASTM D790 using a 3.2 mm thick test bar that has been conditioned at 23° C., 50% relative humidity for 48 hours.

[0141] In certain embodiments, the cellulose ester composition contains 1 wt%-30 wt% or 2 wt%-15 wt% of an impact modifier based on the total weight of the cellulose ester composition, and has an HDT value greater than 85°C, or 90°C, an Izod notched impact strength value greater than 80 J / m, or 100 J / m, or 120 J / m, and a viscosity less than 10000P at 240°C and 400 rad / s.

[0142] In certain embodiments, the cellulose ester composition contains 1 wt%-30 wt% or 2 wt%-15 wt% of an impact modifier based on the total weight of the cellulose ester composition, and has an HDT value greater than 85°C, or 90°C, an Izod notched impact strength value greater than 80 J / m, or 100 J / m, or 120 J / m, and a light transmittance measured according to ASTM D1003 using a 3.2 mm plate after injection molding at a barrel set point of 249°C and a residence time of 5 minutes greater than 70%, or at least 75%, or at least 80%, or at least 85%, or at least 90%.

[0143] In certain embodiments, the cellulose ester composition contains 1 wt%-30 wt% or 2 wt%-15 wt% of an impact modifier based on the total weight of the cellulose ester composition, and has an HDT value greater than 85°C, or 90°C, an Izod notched impact strength value greater than 80 J / m, 100 J / m or 120 J / m, and does not squeak or have screw recovery problems during injection molding at a barrel set point of 249°C.

[0144] In certain embodiments, the cellulose ester composition contains 1 wt%-30 wt% or 2 wt%-15 wt% of an impact modifier based on the total weight of the cellulose ester composition, and has an HDT value greater than 85°C, or 90°C, an Izod notched impact strength value greater than 150 J / m, and does not squeak or have screw recovery problems during injection molding at a barrel set point of 249°C.

[0145] In another embodiment, the cellulose ester composition further comprises at least one additive selected from the group consisting of antioxidants, heat stabilizers, release agents, antistatic agents, brighteners, colorants, flow aids, processing aids, plasticizers, anti-fog additives, minerals, UV stabilizers, lubricants, chain extenders, nucleating agents, reinforcing fillers, wood or flour fillers, glass fibers, carbon fibers, flame retardants, dyes, pigments, colorants, other resins, and combinations thereof.

[0146] In an embodiment, reinforcing material can be used in the composition. Reinforcing material can include but is not limited to carbon filaments, silicates, mica, clay, talcum powder, titanium dioxide, wollastonite, glass flakes, glass beads and fibers and polymer fibers and combinations thereof. In one embodiment, reinforcing material is glass, such as a mixture of fiberglass filaments, glass and talcum powder, a mixture of glass and mica, and a mixture of glass and polymer fibers.

[0147] In certain embodiments, in addition to the impact modifier and friction additive and optional monomeric plasticizer and / or PAP (as described herein), the cellulose ester composition further comprises a stabilizer selected from the group consisting of a secondary antioxidant, an acid scavenger, or a combination thereof. In certain embodiments, in addition to the impact modifier and friction additive and optional monomeric plasticizer and / or PAP (as described herein), the cellulose ester composition further comprises a secondary antioxidant in an amount ranging from about 0.01 wt % to about 0.8 wt %, or from about 0.05 wt % to about 0.5 wt %, or from about 0.08 wt % to about 0.4 wt %, or from about 0.1 wt % to about 0.3 wt %, based on the total weight of the composition. In certain embodiments, the cellulose ester composition comprises, in addition to the impact modifier and friction additive and optional monomeric plasticizer and / or PAP (as described herein), an acid scavenger in an amount ranging from about 0.2 wt % to about 5 wt %, or from about 0.5 wt % to about 4 wt %, or from about 0.5 wt % to about 3 wt %, or from about 0.75 wt % to about 3.5 wt %, or from about 1 wt % to about 3 wt %, or from about 1 wt % to about 2 wt %, or from about 1.5 wt % to about 2.5 wt %, based on the total weight of the composition. In one embodiment, the cellulose ester composition includes, in addition to the impact modifier and friction additive and optional monomeric plasticizer and / or PAP (as described herein), a secondary antioxidant in the range of 0.01 wt % to about 0.8 wt %, or from about 0.05 wt % to about 0.5 wt %, or from about 0.08 wt % to about 0.4 wt %, or from about 0.1 wt % to about 0.3 wt %, and an acid scavenger in the range of about 0.2 wt % to about 5 wt %, or from about 0.5 wt % to about 4 wt %, or from about 0.5 wt % to about 3 wt %, or from about 0.75 wt % to about 3.5 wt %, or from about 1 wt % to about 3 wt %, or from about 1 wt % to about 2 wt %, or from 1.5 wt % to about 2.5 wt %, based on the total weight of the composition. In an embodiment, the weight ratio of acid scavenger to secondary antioxidant is in the range of 4:1 to 25:1, or 5:1 to 20:1, or 6:1 to 18:1, or 7:1 to 15:1, or 8:1 to 15:1, or 9:1 to 15:1, or 10:1 to 15:1, or 9:1 to 14:1, or 9:1 to 13:1, or 9:1 to 12:1, or 10:1 to 14:1, or 10:1 to 13:1, or 10:1 to 12:1.

[0148] In an embodiment, the auxiliary antioxidant is a pentaerythritol diphosphite compound having a melting point of 200°C or less, or 190°C or less, or 180°C or less. In an embodiment, the auxiliary antioxidant is bis(dialkylphenyl)pentaerythritol diphosphite. In one embodiment, the auxiliary antioxidant is 3,9-bis(2,4-di-tert-butylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane. In one embodiment, the acid scavenger is an epoxidized fatty acid ester, such as epoxidized soybean oil. In one embodiment, the cellulose ester composition further comprises, for example, a salt stabilizer in the range of about 0.1 wt % to about 0.5 wt % based on the total weight of the composition. In one embodiment, in addition to the cellulose ester, impact modifier, friction additive and optional monomeric plasticizer and / or PAP and / or stabilizer (as described herein), the cellulose ester composition also contains less than 5 wt%, or less than 2 wt%, or less than 1 wt%, or less than 0.5 wt% of any other components based on the total weight of the composition. It should be noted that additives / components can play more than one role in the cellulose ester composition. The different (or specific) functions of any particular additive (or component) in the cellulose ester composition can depend on its physical properties (e.g., molecular weight, solubility, melting temperature, Tg, etc.) and / or the amount of such additive / component in the entire composition. For example, epoxidized oil (e.g., epoxidized soybean oil) can be used as a plasticizer in one form (e.g., with one molecular weight, number of reactive groups, or weight percentage in the composition), or as an acid scavenger (with little or no plasticizing effect) with another molecular weight, number of reactive groups, or weight percentage in the composition.

[0149] In certain embodiments, the cellulose ester composition does not contain maleic anhydride modified EVA. In certain embodiments, the cellulose ester composition does not contain polyether ester compounds. In certain embodiments, the cellulose ester composition does not contain adipic acid compounds. In certain embodiments, the cellulose ester composition comprises 60wt%-99wt% of one or more cellulose esters, 1wt%-30wt% of one or more impact modifiers, 0.1wt% to 10wt% of friction additive components, and less than 5wt% of other components in total, based on the total weight of the cellulose ester composition. In certain embodiments, such other components do not include plasticizers, polyether ester compounds, or adipic acid compounds. In certain embodiments, the cellulose ester composition contains a dioctyl adipate (DOA) plasticizer and does not contain other adipic acid compounds.

[0150] In another embodiment, a process for preparing a cellulose ester composition is provided. The process includes combining at least one cellulose ester, at least one impact modifier, a friction additive component, and optionally at least one plasticizer and / or PAP and / or stabilizer. Cellulose esters, impact modifiers, friction additive components, plasticizers, PAPs, and stabilizers have been previously discussed in this disclosure. In one embodiment, the cellulose ester and other components can be mixed in any order of addition.

[0151] In another embodiment, a process for preparing a cellulose ester composition is provided, comprising: a) mixing at least one impact modifier, at least one cellulose ester, a friction additive component, and optionally at least one plasticizer and / or PAP and / or stabilizer for a sufficient time and temperature to disperse the components (including the impact modifier) ​​to prepare the cellulose ester composition. Sufficient temperature is defined as the flow temperature of the cellulose ester, which is generally about 50°C higher than the Tg of the cellulose ester. In another embodiment, the temperature is about 80°C higher than the Tg of the cellulose ester. In an embodiment, the upper limit of the temperature during mixing is limited by the processing temperature of the impact modifier and the lower limit is limited by the maximum use temperature of the cellulose ester composition.

[0152] The efficiency of mixing two or more viscoelastic materials can depend on the viscosity ratio of the viscoelastic materials. In one embodiment, for a given mixing equipment and shear rate range, the viscosity ratio of the dispersed phase (including the impact modifier) ​​and the continuous phase (cellulose ester) should be within a specified range to obtain sufficient particle size.

[0153] In an embodiment, the mixing of the impact modifier, cellulose ester, friction additive and any other additives can be accomplished by any method known in the art sufficient to disperse the additives into the cellulose ester. Examples of mixing equipment include, but are not limited to, Banbury mixers, Brabender mixers, roll mills, and extruders (single screw or twin screw). The shear energy during mixing depends on a combination of equipment, blade design, rotation speed (rpm), and mixing time. The shear energy should be sufficient to disperse the impact modifier (and other dispersed phase components, if present) throughout the cellulose ester.

[0154] In an embodiment, cellulose ester, impact modifier, friction additive, plasticizer and other additives can be combined in any order during the process. In one embodiment, cellulose ester is premixed with impact modifier and / or plasticizer. Then the cellulose ester containing impact modifier and / or plasticizer is mixed with other additives. In another embodiment, when using reactive impact modifier, reactive impact modifier can be mixed with cellulose ester first, and then other components are added.

[0155] Composition can be used as molded plastic products or parts (or solid plastic objects). Composition is applicable to any application that needs hard plastics. The example of such parts includes disposable cutlery, fork, spoon, plate, cup, straw and eyeglass frame, toothbrush handle, toy, automobile interior, tool handle, camera parts, electronic equipment parts, razor parts, ink pen holder, disposable syringe, bottle etc. In one embodiment, composition can be used as plastics, film, fiber and sheet. In one embodiment, composition can be used as plastics to make the hard decoration (such as snap, buckle, button or zipper) of bottle, bottle cap, eyeglass frame, tableware, disposable tableware, tableware handle, shelf, shelf partition, electronic equipment housing, electronic equipment box, computer display, printer, keyboard, pipe, auto parts, automotive interior parts, automobile interior, sign, thermoforming letters, siding, toy, thermally conductive plastic, ophthalmic lens, tool, tool handle, utensil or clothing. In another embodiment, the composition can be suitable for use as a film, sheet, fiber, molded article, medical device, packaging, bottle, bottle cap, eyeglass frame, tableware, disposable tableware, tableware handle, shelf, shelf divider, furniture component, electronic device housing, electronic device box, computer display, printer, keyboard, tube, toothbrush handle, automotive parts, automotive interior parts, automotive interior, sign, outdoor sign, skylight, multilayer film, thermoformed letter, siding, toy, toy parts, thermally conductive plastic, ophthalmic lens and frame, tool, tool handle and utensils, health care supplies, commercial food service products, box, film for graphic arts applications and plastic film for plastic glass laminate. In an embodiment, the article can be an acoustic article, for example, an article selected from integrated audio devices, including speakers in cars, TVs and smartphones; stand-alone speakers (wired or wireless), home theater systems, including sound bars, subwoofers and under-TV speakers; smart speakers, including WiFi streaming and virtual personal assistants; and headphones, earbuds and other wearable speakers. In embodiments, the acoustic article may also be a component or part of any of these devices, such as a housing, a casing, a speaker assembly, a microphone assembly, a headband, a wristband, a clamp, a handle, and the like.

[0156] The composition may also be used to form injection moulded toys. In particular, the composition may be used to form injection moulded construction toys or components thereof. The term "construction toy" as used herein comprises conventional toy building elements in the form of box-shaped building blocks provided with knobs on the upper side and complementary tubes on the lower side. Figure 1 and Figure 2 A conventional box-shaped toy building block is shown. The conventional box-shaped toy building block was first disclosed in U.S. Pat. No. 3,005,282 and is and The term also includes other similar box-shaped building blocks that are manufactured by companies other than the LEGO Group and therefore sold under trademarks other than the LEGO trademark.

[0157] The term "construction toy" also includes other types of toy building elements, which are provided with knobs on their upper side and / or with complementary tubes on their lower side, which may form part of a toy building set, which typically comprises a plurality of building elements that are compatible with each other and can therefore be connected to each other. Such toy building sets are also sold under the LEGO trademark, for example piece( bricks), Mechanical Group( Technic) and Some of these toy building sets include toy building figures, e.g. Minifigures( Minifigures) (see, for example, US 05 / 877,800) with a complementary tube on its underside (see Figure 2 ) so that the element can be connected to other toy building elements in a toy building set. Such toy building figures are also included in the term "toy building element". The term also includes similar toy building elements that are produced by other companies than the LEGO Group and are therefore sold under other trademarks than the LEGO trademark.

[0158] Toy building elements come in a wide variety of shapes, sizes and colors. Block and One difference between the two is the size, All block sizes are Twice the size of a block. Traditional box shape with 4*2 knobs on the top The dimensions of the toy building block are about 3.2 cm long, about 1.6 cm wide, and about 0.96 cm high (excluding the knobs), and the diameter of each knob is about 0.48 cm. In contrast, the upper side has 4*2 knobs. The dimensions of the block were approximately 6.4 cm in length, 3.2 cm in width, and 1.92 cm in height (excluding the knobs), with each knob having a diameter of approximately 0.96 cm.

[0159] The cellulose ester compositions of the present invention can be used to form fibers, films, molded articles and sheets. The methods of forming the cellulose ester compositions into fibers, films, molded articles and sheets can be according to methods known in the art. Examples of potential molded articles include, but are not limited to: medical devices, medical packaging, health care products, commercial food service products (e.g., food pans, glasses and storage boxes, bottles, food processors, blenders and blender bowls, utensils, water bottles, fresh-keeping trays, washing machine front panels, vacuum cleaner parts and toys). Other potential molded articles may include ophthalmic lenses and frames.

[0160] The present invention also relates to articles of manufacture comprising films and / or sheets comprising the cellulose ester compositions described herein. In embodiments, the films and / or sheets may have any thickness apparent to one skilled in the art.

[0161] The present invention also relates to films and / or sheets as described herein. Methods of forming the cellulose ester composition into films and / or sheets may include methods known in the art. Examples of films and / or sheets may include, but are not limited to, extruded films and / or sheets, calendered films and / or sheets, compression molded films and / or sheets, solution cast films and / or sheets. Methods of making films and / or sheets include, but are not limited to, extrusion, calendering, compression molding, wet block processing, dry block processing, and solution casting.

[0162] The present invention also relates to molded articles as described herein. Methods of forming the cellulose ester composition into molded articles may include methods known in the art. Examples of molded articles may include, but are not limited to, injection molded articles, overmolded articles, 2k (or two-color) molded articles, extrusion molded articles, injection blow molded articles, injection stretch blow molded articles, and extrusion blow molded articles. Methods of making molded articles include, but are not limited to, injection molding, injection overmolding, 2k (or two-color) injection molding, extrusion, injection blow molding, injection stretch blow molding, and extrusion blow molding. These processes may include any blow molding process known in the art, including, but not limited to, extrusion blow molding, extrusion stretch blow molding, injection blow molding, and injection stretch blow molding.

[0163] The present invention includes any injection blow molding manufacturing process known in the art. Although not limited thereto, a typical description of the injection blow molding (IBM) manufacturing process involves: 1) melting a composition in a reciprocating screw extruder; 2) injecting the molten composition into an injection mold to form a partially cooled tube (i.e., a preform) with one end closed; 3) moving the preform into a blow mold having a desired finished shape around the preform, and closing the blow mold around the preform; 4) blowing air into the preform to stretch and expand the preform to fill the mold; 5) cooling the molded article; 6) ejecting the article from the mold.

[0164] The present invention includes any injection stretch blow molding manufacturing process known in the art. Although not limited thereto, a typical description of the injection stretch blow molding (ISBM) manufacturing process involves: 1) melting a composition in a reciprocating screw extruder; 2) injecting the molten composition into an injection mold to form a partially cooled tube (i.e., a preform) with one end closed; 3) moving the preform into a blow mold having a desired finished shape around the preform, and closing the blow mold around the preform; 4) stretching the preform using an internal stretch rod, and blowing air into the preform to stretch and expand the preform to fill the mold; 5) cooling the molded article; 6) ejecting the article from the mold.

[0165] The present invention includes any extrusion blow molding manufacturing process known in the art. Although not limited thereto, a typical description of an extrusion blow molding manufacturing process involves: 1) melting a composition in an extruder; 2) extruding the molten composition through a die to form a molten polymer tube (i.e., a parison); 3) clamping a mold having the desired finished shape around the parison; 4) blowing air into the parison to stretch and expand the extrudate to fill the mold; 5) cooling the molded article; 6) ejecting the article from the mold; and 7) removing excess plastic (commonly referred to as flash) from the article.

[0166] The present invention can be further illustrated by the following examples of preferred embodiments thereof, but it should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention unless explicitly stated otherwise.

[0167] Example

[0168] Section 1. Base resin testing

[0169] Cellulose ester composition was prepared by mixing cellulose ester CAP 482-20 (from Eastman) with PBS polymer and impact modifier (IM). PBS polymer was FD92 grade PBS (from PTT MCC Biochem) and IM was KaneAce M570 acrylic core shell impact modifier (from Kaneka). Compounding was performed on a Leistritz 18 mm (50:1 L / D ratio) twin screw extruder at a throughput of 18 lbs / hour, a screw speed of 250 rpm and a barrel temperature of 220°C. The resulting CE composition (C-04) was 86 wt% CAP, 8 wt% PBS and 6 wt% IM.

[0170] C-04 resin and several other commercially available resins were subjected to a battery of tests designed to establish a baseline for the performance of cellulose ester compositions in terms of physical properties and frictional performance.

[0171] Physical properties typically reported on the Technical Data Sheet (TDS) are evaluated using injection molded tensile or bend bars using established test methods defined by ASTM. For commercial resins, the drying and processing conditions reported on the technical data sheet are used for molding. For modified resins, the processing conditions used are selected using the processing conditions of the base resin.

[0172] Multiple tests were performed on all samples, including existing commercial resins as well as developed modified resins detailed in Section 3 below. These test methods are broken down as follows:

[0173] ·Specific physical properties usually found in the data sheet. Specific tests include tensile properties (ASTM D638), flexural properties (ASTM D790), Izod notched impact properties (ASTM D256), and heat deformation properties (ASTM D648). In all cases, commercial resins and developed modified resins follow standard conditioning and testing protocols.

[0174] The friction properties of the base resin, reported as static and dynamic coefficients of friction (μ s and μ k ), using a custom in-house test method comparable to the traditional and standardized friction sliding sled test (ASTM D1894). These values ​​are measured using a Bruker Tribometer by intentionally contacting the surfaces of a pair of 4"x4"x1 / 8" plates prepared by injection molding. Gloves are always worn to avoid direct contact with the specimens to avoid contaminating the friction data measurement. After molding, the coefficient of friction is measured using a pair of plates according to the following definition:

[0175] οStatic friction coefficient (μ s ), the contact force between the two plates (F z ) and the relative speed between the two contact plates (v x ) are close to zero, for example:

[0176] ·F z =0.05N,v x =0.01mm / s

[0177] ο Dynamic friction coefficient (μ k ), which is defined as the friction between two contacting plates measured at a constant force and relative velocity, for example:

[0178] ·F z =3.00N, v x =10.0mm / s

[0179] A summary of the commercial resins evaluated as "control" or "negative" examples is shown in Table 1:

[0180] Table 1. Summary of “Control” or “Counter” Materials Evaluated

[0181]

[0182] A summary of the physical properties of the control / reverse materials is shown in Table 2:

[0183] Table 2—Summary of the physical properties of the materials in Table 1.

[0184]

[0185] As can be seen from the physical property data in Table 2, resins C-01 and C-02 (ABS and polycarbonate (PC), respectively) exhibit higher stiffness than all other evaluated materials in terms of tensile modulus and flexural modulus. Resins C-03 and C-04 (cellulosic materials) exhibit similar tensile properties (except modulus) compared to C-01, as well as similar impact toughness as measured by notched Izod impact testing. Resins C-06 and C-07 have significantly lower toughness than C-01, while resin C-05 has the lowest stiffness of all evaluated commercial resins.

[0186] The friction properties of the materials in Table 1 were evaluated to quantify the static and kinetic friction coefficients (μ s and μ k ). The coefficient of friction (COF) values ​​are listed in Table 3 below.

[0187] Table 3. Summary of friction characteristics:

[0188]

[0189] Table 3 shows that C-01 (ABS) and C-02 (PC) have similar friction properties in terms of static and dynamic coefficients of friction when measured according to the sled test (Table 3). In addition, the friction performance of resin C-01 is lower compared to all the resins evaluated. Therefore, in order to make applications that previously used ABS materials and required similar friction behavior functional, it is necessary to modify the friction properties of other resins (such as C-03 to C-07) to match the performance of C-01 in friction testing while maintaining (or not significantly reducing) the physical properties compared to the unmodified base resin, especially stiffness and impact toughness.

[0190] Section 2. Modification

[0191] Modified samples were generated using twin screw compounding and various additives to modify properties, especially by incorporating various additives to modify friction characteristics. The additive chemistries tested varied from short chain molecules (e.g., waxes) to high molecular weight or ultra-high molecular weight organosiloxanes (e.g., PDMS). In the compounded formulations, it was found that the additives could act as internal and / or external lubricants, depending on the specific additive chemistry, molecular weight, loading level, and functionality. The friction additives used are listed in Table 4 below.

[0192] Table 4. Friction additives used to modify resins

[0193] sample additive T-01 Genioplast S T-02 Tegomer H-Si 6441P T-03 Dowsil 4-7081

[0194] Section 3. Examples

[0195] Multiple samples of cellulose ester compositions were generated by modification with different friction additives and different amounts of additives. The samples were prepared by compounding using a 30 mm or 40 mm twin screw extruder at 25 lbs / h with a 2-hole die or 150 lbs / h with a 5-hole die. All solids were premixed and fed into a once-through loss-in-weight feeder at the extruder feed port. Any liquid was fed using a liquid loss-in-weight feeder at the first inlet downstream of the extruder feed port. The extruder barrel temperature increased from the feed port to the die as follows: 100°C at the feed port, 175°C, 200°C and 225°C at the die. The melt temperature was measured to be 218°C-224°C. The extruded polymer strands were cooled using a water bath and an air knife and pelletized using a pellet chopper system to prepare 2x3 mm cylindrical pellets.

[0196] Physical properties were measured before and after a heat aging regimen. The friction performance of each formulation was also evaluated using application-specific homogeneous functional tests. The results are reported in the table below, summarizing the performance of the modified formulations compared to the control examples.

[0197] Table 5 summarizes the formulations evaluated in this study, CE-01 through CE-12, including the specific composition of the friction additives, compared to the control or negative examples. Please note: The “Base Resin” used for all friction modified cellulose ester samples was C-04.

[0198] Table 5. Summary of Example Formulations Evaluated

[0199]

[0200]

[0201] The physical properties and performance of all control, reverse and / or modified resins in Table 5 were measured according to the previously mentioned procedures and test methods. Table 6 below shows a summary of the physical properties including tensile properties, notched Izod impact toughness, flexural modulus and heat distortion temperature.

[0202] Table 6. Summary of TDS properties of example formulations:

[0203]

[0204] *NB = No break, P = Partial break, H = Hinge break, C = Complete break

[0205] As can be seen from Table 6, the formulations with different friction additive types and loading levels maintain tensile properties (yield strength, yield strain, breaking strength, breaking strain) compared to C-01 and unmodified cellulose materials (C-03 and C-04). Specifically, some embodiments (e.g., TR-04, TR-10, and TR-11) maintain similar tensile modulus and / or flexural modulus compared to unmodified cellulose formulations C-03 and / or C-04; some embodiments (e.g., TR-02, TR-09, and TR-12) exhibit improved tensile modulus and / or flexural modulus compared to unmodified cellulose formulations C-03 and / or C-04; and some embodiments (e.g., TR-07, TR-11, and TR-12) exhibit similar Izod notched impact properties and / or heat deformation properties compared to unmodified cellulose formulation C-04.

[0206] The physical properties of some examples were also evaluated after the accelerated aging regimen. This was accomplished by subjecting the samples to a heat aging regimen and then testing the heat aged bars for physical properties according to the standard ASTM test methods summarized previously. Testing was performed both before and after heat exposure to check if the friction modifiers and additives resulted in any substantial changes in performance and physical properties. Table 7 lists the tensile properties measured after standard conditioning (23°C and 50% RH for 72 hours) and heat aging regimen (60°C for 200 hours).

[0207] Table 7. TDS properties of the examples after heat aging.

[0208]

[0209]

[0210] As can be seen from Table 7, the measured properties changed very little compared to Example C-01.

[0211] Finally, the friction performance of some of the modified samples was compared with the control samples C-03 and C-04. The results are listed in Table 8 below.

[0212] Table 8. Summary of friction characteristics.

[0213]

[0214] As can be seen from Table 8, the static and dynamic COF of the modified examples are reduced compared to the C-03 and C-04 samples, with TR-07 and TR-08 having the largest COF reductions and lower loading levels than TR-03 and TR-12. It is also noted that the COF value of the bio-based TR-08 example is close to the COF value of the fossil fuel-based resin C-01.

[0215] The optical clarity (i.e., percent haze) of the samples in Table 8 was evaluated. The percent haze was measured using a Datacolor 650 instrument with a haze add-on, under a C2 illuminant, with a medium area field of view and a UV 400 filter. Two measurements were made, one in full transmission and one in diffuse transmission. The resulting haze values ​​are listed in Table 9 below.

[0216] Table 9: Summary of haze properties.

[0217] sample Haze(%) C-03 8.7 C-04 9.8 TR-03 58.2 TR-07 58.6 TR-08 70.0 TR-12 18.9

[0218] As can be seen in Table 9, the TR-12 formulation has significantly lower haze compared to the other COF additive modified formulations tested.

[0219] Section 3. Injection molded toy building blocks

[0220] like Figure 1 The toy building blocks shown have been injection molded. These building blocks are injection molded by resin C-04 and modified resins TR-03, TR-07, TR-08 and TR-09, respectively. Size and Dimensional manufacturing. The injection molding parameters for manufacturing toy building blocks are as follows:

[0221]

[0222] Resin C-03, the commercially available TREVA grade, has a low impact strength and breaks in a brittle mode (when tested according to the requirements for toy building elements), making it unsuitable for the manufacture of toy building elements. In addition to this, resin C-03 has an extremely high friction, which also makes this resin unsuitable for toy building elements, as the elements stick together and cannot be easily separated.

[0223] Resin C-04 has appropriate impact strength and is suitable as a material for toy building elements, but its friction characteristics need to be modified by adding the COF additives mentioned in Table 5 above.

[0224] Therefore, toy building elements made of modified resin TR-03 with 1% Dowsil 4-7081 additive and modified resin TR-07 with 0.5% Genioplast-S additive were tested, but these resins did not perform well in LEGO 2x4 blocks because the friction was very high and the blocks could not be separated (joined-disassembled), resulting in a poor play experience. It seems that a higher amount of these COF additives is needed to obtain the right friction level.

[0225] Toy building elements of modified resins TR-08 and TR-09 containing 0.75% and 1.0% Genioplast-S additive were also manufactured and tested. The results showed that these toy building elements had appropriate friction.

[0226] The invention has been described in detail with particular reference to certain embodiments thereof, but it will be understood that various changes and modifications can be effected within the spirit and scope of the invention.

Claims

1. A cellulose ester composition comprising: (a) at least one cellulose ester; (b) at least one impact modifier in an amount from about 1 weight percent to about 15 weight percent; (c) at least one friction additive selected from waxes and silicones in an amount of from about 0.1% to about 15% by weight; and (d) optionally, one or more plasticizers in an amount of 0 wt % to about 15 wt %; The composition has a HDT value of greater than 85°C at 0.455 MPa, and a notched Izod impact strength value of greater than 80 J / m measured at 23°C according to ASTM D256 after conditioning a 3.2 mm thick test bar at 230°C and 50% RH for 48 hours.

2. The composition according to claim 1, wherein The friction additive is a wax.

3. The composition according to claim 1, wherein The friction additive is siloxane.

4. The composition according to claim 1, wherein The friction additive is present in an amount of about 0.1 wt % to about 4 wt %.

5. The composition according to claim 1, wherein The impact modifier is present in an amount of about 2 wt % to about 10 wt %.

6. The composition according to claim 1, wherein The impact modifier is a core-shell impact modifier.

7. The composition according to claim 6, wherein The impact modifier is selected from acrylic core-shell impact modifier, ABS core-shell impact modifier or MBS core-shell impact modifier.

8. The composition according to claim 7, wherein The impact modifier is an acrylic core-shell impact modifier.

9. The composition according to claim 8, wherein The impact modifier has a refractive index of 1.46-1.50 and a particle size of 0.01 μm-2.0 μm.

10. The composition of claim 1 further comprising at least one polymeric aliphatic polyester (PAP) in an amount of about 4 wt % to about 12 wt % based on the total cellulose ester composition, wherein the PAP is an aliphatic polyester comprising residues of C2 to C4 alkane diols and residues of C4 to C8 alkyl dicarboxylic acids or residues of ring-opened lactones.

11. The composition according to claim 10, wherein The at least one PAP is selected from polyethylene succinate (PES), polybutylene succinate (PBS), polyethylene adipate (PEA), polybutylene adipate (PBA), or mixtures thereof.

12. The composition according to claim 10, wherein The at least one PAP is polybutylene succinate (PBS) or a copolymer of polybutylene succinate and polybutylene adipate (PBSA).

13. The composition according to claim 12, wherein The PAP is PBS or PBSA having an MFR (190° C., 2.16 kg) of less than 25.

14. The composition according to claim 12, wherein The PAP is a PBS or PBSA having an elongation at break of 250% or more.

15. The cellulose ester composition according to any one of claims 1 to 14, wherein The cellulose ester is selected from one or more of cellulose propionate (CP), cellulose butyrate (CB), cellulose acetate propionate (CAP), cellulose acetate butyrate (CAB), cellulose propionate butyrate (CPB), cellulose tripropionate (CTP) or cellulose tributyrate (CTB).

16. The composition according to any one of claims 1 to 15, wherein The cellulose ester is selected from cellulose acetate propionate (CAP) or cellulose acetate butyrate (CAB), and wherein the composition comprises 0 wt % to less than 5 wt % of a plasticizer.

17. The composition according to any one of claims 1 to 16, wherein The composition further comprises at least one additive selected from the group consisting of antioxidants, heat stabilizers, mold release agents, antistatic agents, brighteners, colorants, plasticizers, minerals, UV stabilizers, lubricants, nucleating agents, reinforcing fillers, glass fibers, carbon fibers, flame retardants, dyes, pigments, colorants, other resins, and combinations thereof.

18. The composition according to claim 17, wherein The total amount of the additives is less than 2 wt %, or less than 1 wt %, based on the total weight of the cellulose ester composition.

19. The composition according to claim 18, wherein The total amount of the additives, excluding the impact modifier, friction additive, plasticizer and PAP, is less than 2 wt%, or less than 1 wt%, based on the total weight of the cellulose ester composition.

20. The composition according to any one of claims 1 to 19, wherein The composition comprises from about 0.05 wt % to about 0.5 wt % of a secondary antioxidant and from about 0.5 wt % to about 3 wt % of an acid scavenger based on the total weight of the composition.

21. The composition according to claim 20, wherein The weight ratio of the acid scavenger to the auxiliary antioxidant is 5:1 to 20:

1.

22. The composition according to any one of claims 1 to 21, wherein The composition has a static COF of 0.6 or less and a dynamic COF of 0.5 or less.

23. A shaped article or formed article comprising the polymer composition of any one of claims 1 to 22.

24. The article of claim 23, wherein: The article is a construction toy or a component thereof.

25. The article of claim 23, wherein: The article is an injection-molded construction toy or a component thereof.

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