阅读说明：本技术 抗冲改性的聚酯碳酸酯-聚硅氧烷组合物以及相关制品和增材制造方法 (Impact modified polyestercarbonate-polysiloxane compositions and related articles and additive manufacturing methods ) 是由 萨拉·格里斯哈伯 马尔维卡·比哈里 保罗·迪安·西贝特 凯利·莱昂 于 2019-03-27 设计创作，主要内容包括：一种组合物包括特定量的嵌段聚碳酸酯-聚硅氧烷、核-壳抗冲改性剂和任选的嵌段聚酯碳酸酯。核-壳抗冲改性剂具有包括聚二甲基硅氧烷或聚(丙烯酸丁酯)或两者的核,并且壳包括聚(甲基丙烯酸甲酯)。嵌段聚酯碳酸酯-聚硅氧烷和嵌段聚酯碳酸酯以大于60wt％至99wt％的总量存在。并且嵌段聚酯碳酸酯-聚硅氧烷向组合物提供0.3至0.7wt％的二甲基硅氧烷单元。还描述了包含该组合物的制品,以及利用该组合物进行增材制造的方法。(A composition includes specific amounts of a block polycarbonate-polysiloxane, a core-shell impact modifier, and optionally a block polyestercarbonate. The core-shell impact modifier has a core comprising polydimethylsiloxane or poly (butyl acrylate) or both, and a shell comprising poly (methyl methacrylate). The block polyestercarbonate-polysiloxane and the block polyestercarbonate are present in a total amount of greater than 60 wt% to 99 wt%. And the block polyestercarbonate-polysiloxane provides 0.3 to 0.7 wt% dimethylsiloxane units to the composition. Articles comprising the composition, and methods of additive manufacturing using the composition, are also described.)

1. A composition comprising, based on the total weight of the composition:

20 to 89 wt% of a block polyestercarbonate-polysiloxane comprising: a polyester block comprising resorcinol ester units having the structure:

a polycarbonate block comprising carbonate units having the structure:

wherein R is¹At least 60% of the total number of groups are aromatic divalent groups; and

a polysiloxane block comprising dimethylsiloxane units; wherein the block polyestercarbonate-polysiloxane comprises 30 to 90 mol% resorcinol ester units, 5 to 35 mol% of wherein R, based on the total moles of carbonate and ester units¹Is a carbonate unit of 1, 3-phenylene and 5 to 35 mol% of a compound in which R is¹Is the following carbonate unit:

and is

Further comprising 0.2 to 4 wt% of dimethylsiloxane units, based on the weight of the block polyestercarbonate-polysiloxane;

1 to 8 wt% of a core-shell impact modifier comprising a shell comprising poly (methyl methacrylate) and a core comprising polydimethylsiloxane, poly (butyl acrylate), or a combination thereof; and

10 to 60 wt% of a block polyestercarbonate comprising: a polyester block comprising resorcinol ester units having the structure:

and

a polycarbonate block comprising carbonate units having the structure:

wherein R is¹At least 60% of the total number of groups are aromatic divalent groups;

wherein the block polyestercarbonate-polysiloxane and the block polyestercarbonate are present in a total amount of greater than 60 wt% to 99 wt%, based on the total weight of the composition; and

wherein the block polyestercarbonate-polysiloxane provides 0.3 to 0.7 wt% dimethylsiloxane units to the composition, based on the total weight of the composition.

2. The composition of claim 1, comprising 20 to 55 wt% of the block polyestercarbonate.

3. The composition of claim 1 or 2, further comprising 1 to 10 wt% of a brominated polycarbonate.

4. The composition of any of claims 1-3, wherein the core of the core-shell impact modifier comprises poly (butyl acrylate).

5. The composition of any of claims 1-3, wherein the core of the core-shell impact modifier comprises polydimethylsiloxane.

6. The composition of any of claims 1-3, wherein the core of the core-shell impact modifier comprises a combination of polydimethylsiloxane and poly (butyl acrylate).

7. The composition of claim 1, comprising:

40 to 58 wt% of the block polyestercarbonate-polysiloxane,

1 to 5 wt% of the core-shell impact modifier, and

40 to 58 wt% of the block polyestercarbonate.

8. The composition according to claim 1, wherein the composition,

wherein the composition comprises:

40 to 62 wt% of the block polyestercarbonate-polysiloxane,

1 to 5 wt% of the core-shell impact modifier,

35 to 55 wt% of the block polyestercarbonate; and

wherein the composition further comprises 1 to 10 wt% of a brominated polycarbonate.

9. An article comprising the composition of any one of claims 1-8.

10. The article of claim 9, wherein the article is an injection molded article.

11. The article of claim 9, wherein the article is a filament having a diameter of 1 to 5 millimeters.

12. The article of claim 9, wherein the article comprises at least two continuous layers, each comprising the same composition.

13. A method of additive manufacturing, the method comprising:

melt extruding the composition of any one of claims 1-8 to form a first melt extrudate;

depositing the first molten extrudate in a predetermined pattern to form a first layer comprising an upper surface;

further melt extruding the same composition to form a second melt extrudate; and

depositing the second molten extrudate in a predetermined pattern to form a second layer comprising a lower surface in contact with the upper surface of the first layer.

14. The method of claim 13, wherein the composition comprises:

40 to 58 wt% of the block polyestercarbonate-polysiloxane,

1 to 5 wt% of the core-shell impact modifier, and

40 to 58 wt% of the block polyestercarbonate.

15. The method of claim 13, wherein the first and second light sources are selected from the group consisting of,

wherein the composition comprises:

40 to 62 wt% of the block polyestercarbonate-polysiloxane,

1 to 5 wt% of the core-shell impact modifier,

35 to 55 wt% of the block polyestercarbonate; and

wherein the composition further comprises 1 to 10 wt% of a brominated polycarbonate.

Background

By additive manufacturing, layer-by-layer deposition or "printing" of thermoplastic materials can be used to fabricate three-dimensional parts. The method utilizes a computer-controlled moving extrusion head to form a series of layers, each layer being formed by extruding a molten thermoplastic material onto an underlying layer. The thermoplastic material must have a combination of properties that enable it to be extruded in molten form, adhere to adjacent layers, and provide impact strength to the printed part. In addition, for applications such as interior components of aircraft and rail vehicles, thermoplastic materials must provide stringent flame retardant properties. It is difficult for a single thermoplastic material to meet all of these requirements. Accordingly, there remains a need for thermoplastic materials and methods that can be used for three-dimensional part printing and provide an improved balance of impact strength and flame retardancy to the printed part.

Disclosure of Invention

One embodiment is a composition comprising, based on the total weight of the composition: 20 to 89 weight percent of a block polyestercarbonate-polysiloxane comprising a polyester block comprising resorcinol ester units having the structure

A polycarbonate block comprising a carbonate unit having the structure

Wherein R is¹At least 60% of the total number of groups are aromatic divalent groups; and a polysiloxane block comprising dimethylsiloxane units; wherein the block polyestercarbonate-polysiloxane comprises 30 to 90 mol% resorcinol ester units, 5 to 35 mol% of wherein R, based on the total moles of carbonate and ester units¹Carbonate units which are 1, 3-phenylene, and from 5 to 35 mol% of a compound in which R is¹Is the following carbonate unit:

and is

It also includes: 0.2 to 4 wt% dimethylsiloxane units, based on the weight of the block polyestercarbonate-polysiloxane; 1 to 8 wt% of a core-shell impact modifier comprising a shell comprising poly (methyl methacrylate) and a core comprising polydimethylsiloxane, poly (butyl acrylate), or a combination thereof; and 10 to 60 wt% of a block polyester carbonate comprising a polyester block of resorcinol ester units having the structure

And

a polycarbonate block comprising a carbonate unit having the structure

Wherein R is¹At least 60% of the total number of groups are aromatic divalent groups; wherein the block polyestercarbonate-polysiloxane and the block polyestercarbonate are present in a total amount of greater than 60 wt% to 99 wt%, based on the total weight of the composition; and wherein based on the total weight of the compositionThe block polyestercarbonate-polysiloxane provides the composition with 0.3 to 0.7 wt% of dimethylsiloxane units.

Another embodiment is an article comprising the composition.

Another embodiment is a method of additive manufacturing, the method comprising: melt extruding the composition to form a first melt extrudate; depositing a first molten extrudate in a predetermined pattern to form a first layer comprising an upper surface; further melt extruding the same composition to form a second melt extrudate; and depositing the second molten extrudate in a predetermined pattern to form a second layer comprising a lower surface in contact with the upper surface of the first layer.

These and other embodiments are described in detail below.

Drawings

The figure shows the print (layer) orientation of an exemplary test article used to determine tensile properties and izod impact strength.

Detailed Description

The present inventors have determined that by a composition comprising specific amounts of a block polyestercarbonate-polysiloxane, a core-shell impact modifier and optionally a block polyestercarbonate, an improved balance of suitability for three-dimensional printing and impact strength and flame retardancy is provided. The core-shell impact modifier comprises a core comprising poly (butyl acrylate) or polydimethylsiloxane, or a combination thereof, and a shell comprising poly (methyl methacrylate).

Accordingly, one embodiment is a composition comprising, based on the total weight of the composition: 20 to 89 weight percent of a block polyestercarbonate-polysiloxane comprising a polyester block comprising resorcinol ester units having the structure

A polycarbonate block comprising a carbonate unit having the structure

Wherein R is¹At least 60% of the total number of groups are aromatic divalent groups; and a polysiloxane block comprising dimethylsiloxane units; wherein the block polyestercarbonate-polysiloxane comprises 30 to 90 mol% resorcinol ester units, 5 to 35 mol% of wherein R, based on the total moles of carbonate and ester units¹Carbonate units which are 1, 3-phenylene, and from 5 to 35 mol% of a compound in which R is¹Is the following carbonate unit:

and is

It also includes: 0.2 to 4 wt% dimethylsiloxane units, based on the weight of the block polyestercarbonate-polysiloxane; 1 to 8 wt% of a core-shell impact modifier comprising a shell comprising poly (methyl methacrylate) and a core comprising polydimethylsiloxane, poly (butyl acrylate), or a combination thereof; and 10 to 60 wt% of a block polyester carbonate comprising a polyester block of resorcinol ester units having the structure

And

a polycarbonate block comprising a carbonate unit having the structure

Wherein R is¹At least 60% of the total number of groups are aromatic divalent groups; wherein the block polyestercarbonate-polysiloxane and the block polyestercarbonate are present in a total amount of greater than 60 wt% to 99 wt%, based on the total weight of the composition; and wherein the block polyestercarbonate-polysiloxane provides 0.3 to 0.7 wt% dimethylsiloxane units to the composition, based on the total weight of the composition.

The composition comprises a block polyestercarbonate-polysiloxane. Block polyestercarbonate-polysiloxanes are copolymers comprising at least one polyester block, at least one polycarbonate block and at least one polysiloxane block. Specifically, at least one of the polyester blocks comprises resorcinol ester units, each resorcinol ester unit having the structure

At least one polycarbonate block comprises carbonate units, each carbonate unit having the structure

Wherein R is¹At least 60% of the total number of groups are aromatic divalent groups and at least one polysiloxane block comprises dimethylsiloxane units.

In some embodiments, the aromatic divalent group is C₆-C₂₄An aromatic divalent group. When not all R¹When the radicals are all aromatic, the remainder are C₂-C₂₄An aliphatic divalent group.

In some embodiments, each R is¹Is a radical of the formula

Wherein A is¹And A²Each of which is independently a monocyclic divalent aryl radical, and Y¹To have one or two A¹And A²A bridging group of separate atoms. A. the¹And A²Examples of (B) include 1, 3-phenylene and 1, 4-phenylene, each optionally substituted with one, two or three C₁-C₆Alkyl substitution. Bridging radical Y¹May be C₁-C₁₂(divalent) alkylene group. As used herein, the term "hydrocarbyl", whether used by itself, or as a prefix, suffix, or fragment of another term, refers to a residue that contains only carbon and hydrogen, unless it is usedAre explicitly identified as "substituted hydrocarbyl". The hydrocarbyl residue may be aliphatic or aromatic, straight chain, cyclic, branched, saturated, or unsaturated. It may also contain combinations of aliphatic, aromatic, straight chain, cyclic, bicyclic, branched, saturated, and unsaturated hydrocarbon moieties. When the hydrocarbyl residue is described as substituted, it may contain heteroatoms over and above carbon and hydrogen. In one embodiment, one atom will be A¹And A²And (4) separating. Y is¹Illustrative examples of radicals are-O-, -S-, -S (O) -, -S (O)₂-, -C (O) -, methylene (-CH)₂-; also known as methylidene), ethylidene (-CH (CH)₃) -) isopropylidene (-COOR-), C (-CH (CH)₃)₂-), neopentylidene, cyclohexylidene, cyclopentadecylidene, cyclododecylidene, adamantylidene, cyclohexylidene methylene, cyclohexylmethylene and 2- [2.2.1]-bicycloheptylidene.

In some embodiments, the resorcinol ester units comprise resorcinol isophthalate/terephthalate units, and the carbonate units comprise resorcinol carbonate units and bisphenol-a carbonate units.

The block polyestercarbonate-polysiloxane comprises 30 to 90 mol% resorcinol ester units, 5 to 35 mol% of where R is based on the total moles of carbonate and ester units¹Carbonate units that are 1, 3-phenylene (i.e., the carbonate units are resorcinol carbonate units), and 5 to 35 mol% of a compound wherein R is¹Is a carbonate unit of:

(i.e., the carbonate units are bisphenol A carbonate units). In the range of 30 to 90 mol%, the amount of resorcinol ester units can be 50 to 90 mol%, or 70 to 90 mol%. In the range of 5 to 35 mol%, the amount of resorcinol carbonate units may be 5 to 25 mol%, or 5 to 15 mol%. In the range of 5 to 35 mol%, the amount of bisphenol a carbonate units may be 5 to 25 mol%, or 5 to 15 mol%. The block polyestercarbonate-polysiloxane further comprises 0.2 to 4 wt% of dimethylsiloxane units, based on the weight of the block polyestercarbonate-polysiloxane. Within this range, the amount of dimethylsiloxane units may be 0.4 to 2 weight percent.

In a very specific embodiment, the block polyestercarbonate-polysiloxane comprises 70 to 90 mol% resorcinol isophthalate/terephthalate units, 5 to 15mol resorcinol carbonate units, and 5 to 15mol bisphenol a carbonate units, based on the total moles of carbonate and ester units, and further comprises 0.2 to 4 wt% or 0.4 to 2 wt% polydimethylsiloxane, based on the total weight of the block polyestercarbonate-polysiloxane.

The structure of the terminal group on the block polyestercarbonate-polysiloxane is not particularly limited. End-capping agents (also known as chain stoppers or chain terminators) may be included during the polymerization to provide end groups. Examples of the blocking agent include monocyclic phenols such as phenol, p-cyanophenol and C₁-C₂₂Alkyl-substituted phenols such as p-cumyl phenol, resorcinol monobenzoate, and p-tert-butyl phenol; monoethers of dihydric phenols such as p-methoxyphenol; monoesters of dihydric phenols such as resorcinol monobenzoate, functionalized chlorides of aliphatic monocarboxylic acids such as acryloyl chloride and methacryloyl chloride; and monochloroformates such as phenyl chloroformate, alkyl-substituted phenyl chloroformate, p-cumyl phenyl chloroformate and toluene chloroformate. Combinations of different end groups may be used. In some embodiments, the block polyestercarbonate-polysiloxane has a weight average molecular weight of 15,000 to 50,000 g/mole as determined by gel permeation chromatography using polycarbonate standards. Within this range, the weight average molecular weight can be 18,000 to 50,000 grams/mole.

Methods for preparing block polyestercarbonate-polysiloxanes are known, for example, as described in U.S. Pat. No. 7,790,292B2 to Colborn et al.

The composition comprises a block polyestercarbonate-polysiloxane in an amount of 20 to 89 wt%, based on the total weight of the composition. Within this range, the amount of block polyestercarbonate-polysiloxane may be 30 to 80 wt%, or 40 to 60 wt%.

The block polyestercarbonate-polysiloxane provides the composition with 0.3 to 0.7 wt% dimethylsiloxane units, based on the total weight of the composition. When the weight percentage of the dimethylsiloxane units is less than 0.3 wt%, the flame retardancy of the composition is impaired. And when the weight percentage of dimethylsiloxane units is greater than 0.7 wt%, the composition is less suitable for three-dimensional printing. In the range of 0.3 to 0.7 wt%, the amount of dimethylsiloxane units may be 0.4 to 0.6 wt%.

In addition to the block polyestercarbonate-polysiloxane, the composition also comprises a core-shell impact modifier. The core-shell impact modifier comprises a shell comprising poly (methyl methacrylate) and a core comprising polydimethylsiloxane, poly (butyl acrylate), or a combination thereof. In some embodiments, the core-shell impact modifier comprises 5 to 40 wt% shell and 60 to 95 wt% core, based on the weight of the core-shell impact modifier. In the range of 5 to 40 wt%, the amount of shell can be 7 to 35 wt%, or 8 to 30 wt%. In the range of 60 to 95 wt%, the amount of core may be 65 to 93 wt%, or 70 to 92 wt%.

In some embodiments, the core of the core-shell impact modifier comprises polydimethylsiloxane. In some embodiments, the core of the core-shell impact modifier comprises poly (butyl acrylate). In some embodiments, the core of the core-shell impact modifier comprises a combination of polydimethylsiloxane and poly (butyl acrylate).

In some embodiments, the core of the core-shell impact modifier comprises polydimethylsiloxane. The polydimethylsiloxane may be prepared by emulsion copolymerization of monomers comprising a source of dimethylsiloxane units. For example, the source of dimethylsiloxane units may include a cyclic dimethylsiloxane (e.g., 1,3,5, 7-octamethylcyclotetrasiloxane (D4)), a silicon-containing monomer comprising two hydrolyzable groups (e.g., dimethyldimethoxysilane), or a combination thereof. The monomers used to form the polydimethylsiloxane may optionally include a crosslinking agent, a grafting agent, or a combination thereof. The crosslinker may comprise a silicon-containing monomer comprising three or more hydrolyzable groups, such as methyltriethoxysilane, tetrapropoxysilane, or a combination thereof. The grafting agent may comprise a silicon-containing monomer comprising at least one hydrolyzable group and a polymerizable carbon-carbon double bond. Examples of grafting agents include methacryloxypropylmethoxydimethylsilane, methacryloxypropyldimethoxymethylsilane, vinyldimethoxymethylsilane, vinylphenylmethoxymethylsilane, vinylphenyldimethoxysilane, and combinations thereof.

In some embodiments, the core of the core-shell impact modifier comprises poly (butyl acrylate). In some embodiments, the core comprises crosslinked poly (butyl acrylate). Crosslinked poly (butyl acrylate) s can be prepared by polymerization of butyl acrylate, optionally in the presence of a monomer comprising at least two polymerizable carbon-carbon double bonds. Examples of such monomers include allyl acrylate, allyl methacrylate, ethylene glycol dimethacrylate, 1, 3-butanediol dimethacrylate, divinylbenzene, and combinations thereof.

In some embodiments, the core of the core-shell impact modifier comprises a combination of polydimethylsiloxane and poly (butyl acrylate). In these embodiments, the core may be described as a polydimethylsiloxane-poly (butyl acrylate) composite rubber. The polydimethylsiloxane component of the composite rubber may be formed by reacting a source of dimethylsiloxane units, such as a cyclic dimethylsiloxane, such as 1,3,5, 7-octamethylcyclotetrasiloxane (D4), a silicon-containing monomer comprising two hydrolyzable groups, such as dimethyldimethoxysilane, or a combination thereof. The monomers used to form the polydimethylsiloxane component of the composite rubber may optionally further include a crosslinking agent, a grafting agent, or a combination thereof. The crosslinker may comprise a silicon-containing monomer comprising three or more hydrolyzable groups, such as methyltriethoxysilane, tetrapropoxysilane, or a combination thereof. The grafting agent may comprise a silicon-containing monomer comprising at least one hydrolyzable group and a polymerizable carbon-carbon double bond. Examples of grafting agents include methacryloxypropylmethoxydimethylsilane, methacryloxypropyldimethoxymethylsilane, vinyldimethoxymethylsilane, vinylphenylmethoxymethylsilane, vinylphenyldimethoxysilane, and combinations thereof. The poly (butyl acrylate) component of the compounded rubber may be formed by polymerizing butyl acrylate, optionally in the presence of a monomer comprising at least two polymerizable carbon-carbon double bonds, a silicon-containing monomer comprising at least one hydrolyzable group and a polymerizable carbon-carbon double bond, or a combination thereof. Examples of monomers comprising at least two polymerizable carbon-carbon double bonds include allyl acrylate, allyl methacrylate, ethylene glycol dimethacrylate, 1, 3-butanediol dimethacrylate, divinylbenzene, and combinations thereof. Examples of silicon-containing monomers comprising at least one hydrolyzable group and a polymerizable carbon-carbon double bond include methacryloxypropylmethoxydimethylsilane, methacryloxypropyldimethoxymethylsilane, vinyldimethoxymethylsilane, vinylphenylmethoxymethylsilane, vinylphenyldimethoxysilane, and combinations thereof. In some embodiments, the compounded rubber comprises 70 to 95 wt% polydimethylsiloxane and 5 to 30 wt% poly (butyl acrylate), based on the weight of the compounded rubber.

The shell of the core-shell impact modifier comprises poly (methyl methacrylate). The shell formed in the presence of the core may be prepared by polymerization of methyl methacrylate. The monomers used to form the shell may optionally further include monomers comprising at least two polymerizable carbon-carbon double bonds. Examples of such monomers include allyl acrylate, allyl methacrylate, ethylene glycol dimethacrylate, 1, 3-butanediol dimethacrylate, divinylbenzene, and combinations thereof.

Core-shell impact modifiers and methods for their preparation are known and described, for example, in U.S. Pat. No. 6,153,694 to Miyatake et al, and U.S. Pat. No. 9,127,154B2 to Li et al, and U.S. patent application publication No. US 2008/0242797A1 to Saegusa et al. Core-shell impact modifiers are also commercially available, for example, PARALOID from Dow chemical company^TMEXL 2335 impact modifier, KANE ACE from Kaneka^TMMR-01 impact modifier and METABLEN from Mitsubishi Chemical^TMSX-005 impact modifier.

The composition comprises the core-shell impact modifier in an amount of 1 to 8 wt%, based on the total weight of the composition. Within this range, the amount of core-shell impact modifier may be 2 to 7 weight percent, or 2 to 6 weight percent, or 1 to 5 weight percent, or 2 to 5 weight percent.

The composition may optionally comprise a block polyestercarbonate. It is understood that block polyestercarbonates are chemically distinct from block polyestercarbonate-polysiloxanes. Specifically, the block polyestercarbonate-polysiloxane comprises at least one polysiloxane block, while the block polyestercarbonate does not comprise a polysiloxane block. The block polyestercarbonates comprise polyester blocks comprising resorcinol ester units having the structure

And

a polycarbonate block comprising a carbonate unit having the structure

Wherein R is¹At least 60 mol% of the total number of groups are aromatic divalent groups. In some embodiments, the aromatic divalent group is C₆-C₂₄An aromatic divalent group. When not all R¹When the radicals are all aromatic, the remainder are C₂-C₂₄An aliphatic divalent group. In some embodiments, each R is¹Is a radical of the formula

Wherein A is¹And A²Each independently a monocyclic divalent aryl radical, and Y¹Is a bridging group having one or two atoms which are different from one another¹And A²And (4) separating. In one embodiment, one atom will be A¹And A²And (4) separating. Illustrative non-limiting examples of such groups are-O-, -S-, -S (O) -, -S (O)₂-, -C (O) -, methylene, cyclohexyl-methylene, 2- [2.2.1]-bicycloheptylidene, ethylidene, isopropylidene, neopentylidene, cyclohexylidene, cyclopentadecylidene, cyclododecylidene, and adamantylidene. Bridging radical Y¹May be C₁-C₁₂(divalent) alkylene group. As used herein, the term "hydrocarbyl", whether used by itself, or as a prefix, suffix, or fragment of another term, refers to a residue that contains only carbon and hydrogen, unless it is specifically identified as "substituted hydrocarbyl". The hydrocarbyl residue may be aliphatic or aromatic, straight chain, cyclic, branched, saturated, or unsaturated. It may also contain combinations of aliphatic, aromatic, straight chain, cyclic, bicyclic, branched, saturated, and unsaturated hydrocarbon moieties. When the hydrocarbyl residue is described as substituted, it may contain heteroatoms over and above carbon and hydrogen. Y is¹Examples of (2) include methylene (-CH)₂-; also known as methylidene), ethylidene (-CH (CH)₃) -) isopropylidene (-COOR-), C (-CH (CH)₃)₂-) and cyclohexylidene.

In some embodiments, the polyester block comprises resorcinol ester units having the structure

And the polycarbonate block comprises bisphenol A carbonate units having the structure

In some embodiments, the block polyester carbonate comprises 30 to 90 mole% resorcinol isophthalate/terephthalate units, 5 to 35 mole% resorcinol carbonate units, and 5 to 35 mole% bisphenol a carbonate units, based on the total moles of carbonate and ester units. Within these ranges, the mole percent of resorcinol isophthalate/terephthalate units can be 50 to 90, the mole percent of resorcinol carbonate units can be 5 to 25, and the mole percent of bisphenol-a carbonate units can be 5 to 25. In a very specific embodiment, the block polyester carbonate comprises 70 to 90 mole% resorcinol isophthalate/terephthalate units, 5 to 15 mole% resorcinol carbonate units, and 5 to 15 mole% bisphenol-a carbonate units.

In some embodiments, the block polyestercarbonate has a weight average molecular weight of 5,000 to 100,000 grams/mole, as determined by Gel Permeation Chromatography (GPC) using a crosslinked styrene-divinylbenzene column and polycarbonate standards. Within this range, the weight average molecular weight can be 10,000 to 50,000 grams/mole, or 10,000 to 40,000 grams/mole.

Methods for preparing block polyestercarbonates are known, including those disclosed in Colborn et al, U.S. Pat. No. 7,790,292B 2.

The block polyestercarbonate may be present in the composition in an amount of 10 to 60 wt%, based on the total weight of the composition. In some embodiments, the amount of block polyestercarbonate is 20 to 55 wt%, or 25 to 50 wt%.

The block polyestercarbonate-polysiloxane and optional block polyestercarbonate are present in a total amount of greater than 60 wt% to 99 wt%, based on the total weight of the composition. Within this range, the total amount of block polyestercarbonate-polysiloxane and optional block polyestercarbonate may be 65 to 95 wt%, or 75 to 95 wt%, or 80 to 95 wt%.

The composition may optionally further comprise a flame retardant. The flame retardant is a compound or mixture of compounds capable of improving the flame retardancy of the composition. Suitable flame retardants include, for example, organophosphates including triphenyl phosphate, resorcinol bis (diphenyl phosphate), and bisphenol a bis (diphenyl phosphate)), metal dialkyl phosphinates including aluminum tris (diethylphosphinate), phosphazenes including hexaphenoxycyclotriphosphazene, melamine-containing flame retardants including melamine phosphate, melamine pyrophosphate, melamine polyphosphate, and melamine cyanurate, metal hydroxides including magnesium hydroxide, aluminum hydroxide, and cobalt hydroxide, halogenated polymers including brominated polycarbonates, in this application, block polyestercarbonate-polysiloxanes are not considered flame retardants, when present, the flame retardants can be used in amounts of 0.5 to 20 weight percent based on the total weight of the composition, in this range, the amount of flame retardant can be 1 to 15 weight percent, or 2 to 12 weight percent, in some embodiments, the composition comprises 5 to 15 wt% of the organophosphate ester, based on the total weight of the composition. In some embodiments, the composition comprises 1 to 10 wt% brominated polycarbonate, based on the total weight of the composition. Within this range, the amount of brominated polycarbonate can be 1 to 9 wt%, or 2 to 8 wt%, or 3 to 8 wt%. In some embodiments, the composition does not comprise a flame retardant.

Optionally, the composition may further comprise one or more additives known in the thermoplastics art. For example, the composition may optionally further comprise a material selected from the group consisting of stabilizers, lubricants, processing aids, anti-drip agents, nucleating agents, UV blockers, dyes, pigments, antioxidants, antistatic agents, mineral oil, metal deactivators, antiblocking agents, and combinations thereof. When present, such additives are generally used in a total amount of less than or equal to 10 wt%, or less than or equal to 5 wt%, or less than or equal to 2 wt%, or less than or equal to 1 wt%, based on the total weight of the thermoplastic material.

In some embodiments, the composition does not include one or at least two or all of a polycarbonate (including polycarbonate homopolymers and polycarbonate copolymers wherein each unit comprises a carbonate linkage), a polyester (including polyester homopolymers and polyester copolymers wherein each unit comprises an ester linkage), a polyestercarbonate comprising an ester unit having a divalent aliphatic group, a styrene-acrylonitrile copolymer, and an acrylonitrile-butadiene-styrene terpolymer. It is to be understood that these optionally do not include polymers that are chemically distinct from the block polyestercarbonate-polysiloxane and the block polyestercarbonate.

In some embodiments, the composition contains the lowest amount of halogen or does not include halogen. For example, the composition may contain 0 to 1 wt% halogen, or the composition may contain 0 to 0.1 wt% halogen, or the composition may not include halogen.

In some embodiments, the composition comprises 0 to 2 weight percent, based on the total weight of the composition, of an organophosphorus compound described in US20140370213a1 of van der Mee et al. Within this limit, the amount of organophosphorus compound can be 0 to 1 wt% or 0 wt%.

In some embodiments, the composition comprises 0 to less than 1 wt% elemental phosphorus, based on the total weight of the composition. Within this limit, the amount of phosphorus can be 0 to 0.1 wt%, or 0 to 0.05 wt%, or 0 wt%.

In a very specific embodiment, the composition comprises 40 to 60 wt.% of the block polyestercarbonate-polysiloxane, 1 to 5 wt.% of the core-shell impact modifier, and 40 to 60 wt.% of the block polyestercarbonate; and the core of the core-shell impact modifier comprises polydimethylsiloxane or poly (butyl acrylate).

In a very specific embodiment, the composition comprises 40 to 60 wt.% of the block polyestercarbonate-polysiloxane, 1 to 5 wt.% of the core-shell impact modifier, 35 to 55 wt.% of the block polyestercarbonate; and the composition further comprises 1 to 10 wt% of a brominated polycarbonate; and the core of the core-shell impact modifier comprises poly (butyl acrylate).

In addition to the composition, another embodiment is an article of manufacture comprising the composition of any of the above variations thereof. The form of the article or the method for producing the same is not particularly limited. In some embodiments, the article is an injection molded article. In some embodiments, the article is a filament having a diameter of 1 to 5 millimeters or 1 to 3 millimeters. In some embodiments, the article comprises at least two continuous layers, each of the at least two continuous layers comprising the same composition. Such articles may be prepared by additive manufacturing.

Another embodiment is a method of additive manufacturing, the method comprising: melt extruding the composition of any of the above variations to form a first melt extrudate; depositing a first molten extrudate in a predetermined pattern to form a first layer comprising an upper surface; further melt extruding the same composition to form a second melt extrudate; and depositing the second molten extrudate in a predetermined pattern to form a second layer comprising a lower surface in contact with the upper surface of the first layer.

In some embodiments of the method, the composition comprises 40 to 60 wt% of the block polyestercarbonate-polysiloxane, 1 to 5 wt% of the core-shell impact modifier, and 40 to 60 wt% of the block polyestercarbonate. In some embodiments, the core of the core-shell impact modifier comprises polydimethylsiloxane. In some embodiments, the core of the core-shell impact modifier comprises poly (butyl acrylate). In some embodiments, the core of the core-shell impact modifier comprises polydimethylsiloxane and poly (butyl acrylate).

In some embodiments of the method, the composition comprises 40 to 60 wt% of the block polyestercarbonate-polysiloxane, 1 to 5 wt% of the core-shell impact modifier, and 35 to 55 wt% of the block polyestercarbonate; and the composition further comprises 1 to 10 wt% of a brominated polycarbonate; and the core of the core-shell impact modifier comprises poly (butyl acrylate).

The present invention includes at least the following embodiments.