Ionomers of ethylene acid copolymers with enhanced creep resistance
阅读说明：本技术 具有增强抗蠕变性的乙烯酸共聚物的离聚物 (Ionomers of ethylene acid copolymers with enhanced creep resistance ) 是由 R·T·H·周 于 2019-07-29 设计创作，主要内容包括：根据一个实施例,一种离聚物包括乙烯酸共聚物和脂肪族单官能有机酸的中和共混物。所述共混物包括按所述共混物的总wt.％计,60到95wt.％,和按所述共混物的总wt.％计,5到40wt.％的所述脂肪族单官能有机酸。所述乙烯酸共聚物为以下的聚合反应产物：乙烯；丙烯酸烷基酯；任选的单羧酸单体；和不饱和二羧酸单体。至少30摩尔％的所述共混物的总酸单元经镁中和盐的镁阳离子中和。(According to one embodiment, an ionomer comprises a neutralized blend of an ethylene acid copolymer and an aliphatic monofunctional organic acid. The blend includes 60 to 95 wt.%, based on the total wt.% of the blend, and 5 to 40 wt.%, based on the total wt.% of the blend, of the aliphatic monofunctional organic acid. The ethylene acid copolymer is the polymerization reaction product of: ethylene; an alkyl acrylate; optionally, a monocarboxylic acid monomer; and unsaturated dicarboxylic acid monomers. At least 30 mole% of the total acid units of the blend are neutralized with the magnesium cations of the magnesium neutralization salt.)
1. An ionomer comprising a neutralized blend of an ethylene acid copolymer and an aliphatic monofunctional organic acid, wherein the blend comprises:
60 to 95 wt.%, based on the total wt.% of the blend, of the ethylene acid copolymer, which is the polymerization reaction product of:
the amount of ethylene is such that the amount of ethylene,
1 to 40 wt.%, based on the total wt.% of monomers present in the ethylene acid copolymer, of an alkyl acrylate;
0 to 20 wt.%, based on the total wt.% of monomers present in the ethylene acid copolymer, of monocarboxylic acid monomers; and
2 to 15 wt.%, based on the total wt.% of monomers present in the ethylene acid copolymer, of unsaturated dicarboxylic acid monomers; and
5 to 40 weight percent, based on the total weight.% of the blend, of the aliphatic monofunctional organic acid, wherein the aliphatic monofunctional organic acid has less than 36 carbon atoms;
wherein at least 30 mole% of the total acid units of the blend are neutralized with the magnesium cations of the magnesium neutralization salt.
2. The ionomer of claim 1 wherein the ethylene acid copolymer comprises 1 to 20 wt.% alkyl acrylate.
3. An ionomer comprising a neutralized blend of a first ethylene acid copolymer, a second ethylene acid copolymer, and an aliphatic monofunctional organic acid, wherein the blend comprises:
the first ethylene acid copolymer is the polymerization reaction product of:
ethylene;
2 to 20 wt.%, based on the total wt.% of monomers present in the first ethylene acid copolymer, of monocarboxylic acid monomers; and
0 to 40 wt.% alkyl acrylate, based on the total wt.% of monomers present in the first ethylene acid copolymer;
the second ethylene acid copolymer is a polymerization reaction product of:
ethylene;
1 to 40 wt.% alkyl acrylate, based on the total wt.% of monomers present in the second ethylene acid copolymer;
0 to 20 wt.% monocarboxylic acid monomers, based on the total wt.% of monomers present in the second ethylene acid copolymer; and
2 to 15 wt.%, based on the total wt.% of monomers present in the second ethylene acid copolymer, of unsaturated dicarboxylic acid monomers; and is
Wherein the ratio of the first ethylene acid copolymer to the second ethylene acid copolymer is 90/10 wt.% to 10/90 wt.%; and
5 to 40 weight percent, based on the total weight.% of the blend, of the aliphatic monofunctional organic acid, wherein the aliphatic monofunctional organic acid has less than 36 carbon atoms;
wherein at least 30 mole% of the total acid units of the blend are neutralized with the magnesium cations of the magnesium neutralization salt.
4. The ionomer of claim 1 or claim 3, wherein at least 70 mol% of the total acid units of the blend are neutralized with the magnesium cations of the magnesium salt.
5. The ionomer of claim 1 or claim 3, wherein the blend is further neutralized with at least one additional cation of a neutralizing salt selected from the group consisting of zinc, lithium and sodium salts.
6. The ionomer of claim 3, wherein in the range of 80 to 100 mole% of the total acid units of the blend are neutralized, wherein 30 to 80 mole% of the total acid units of the blend are neutralized by the magnesium cations of the magnesium salt.
7. The ionomer of claim 1, wherein the second ethylene acid copolymer comprises 20 to 30 wt.% alkyl acrylate.
8. The ionomer of any preceding claim, wherein the unsaturated monocarboxylic acid monomer comprises one or more of acrylic acid, methacrylic acid, or a combination thereof.
9. The ionomer of any one of claims 1-3, wherein 80 to 100% of the total acid units of the blend are neutralized with magnesium cations.
10. The ionomer of any preceding claim, wherein the unsaturated dicarboxylic acid monomer comprises maleic anhydride, monomethyl maleic anhydride, monoethyl maleic anhydride, monopropyl maleic anhydride, monobutyl maleic anhydride, or a combination thereof.
11. The ionomer of any preceding claim, wherein the alkyl acrylate comprises methyl acrylate, ethyl acrylate, n-butyl acrylate, or isobutyl acrylate, or a combination thereof.
12. The ionomer of any preceding claim, wherein the aliphatic monofunctional organic acid is a fatty acid having from 4 to 36 carbon atoms, and optionally from one to three independently selected from C1To C8Alkyl groups.
13. The ionomer of claim 12, wherein the fatty acid comprises at least one of behenic acid, stearic acid, oleic acid, erucic acid, 12-hydroxystearic acid, and isostearic acid.
14. The ionomer of any one of claims 3 to 15, wherein the ratio of the first ethylene acid copolymer to the second ethylene acid copolymer is 90/10 wt.% to 60/40 wt.%.
15. A molded article or foam comprising the ionomer of any one of the preceding claims.
16. The molded article of claim 15, wherein the molded article exhibits improved creep resistance of at least 80 ℃, wherein the molded article exhibits a dimensional change of less than 25% at a stress of 20psi, 80 ℃ for 30 minutes.
Technical Field
Embodiments of the present disclosure generally relate to ionomer resins, and in particular to ionomers comprising the polymerization reaction product of ethylene, monocarboxylic acid monomers, unsaturated dicarboxylic acid monomers, alkyl acrylate monomers, aliphatic monofunctional organic acids, and combinations thereof, which are at least partially neutralized with magnesium cations.
Background
Ionomers are materials commonly used in a variety of applications because they have higher tensile strength, higher transparency, better abrasion resistance, and higher stiffness than the precursor acid copolymers. For example, ionomers of ethylene acid copolymers have found use in many applications, such as food packaging, foamed parts, injection molded parts (e.g., cosmetic containers), and golf ball components.
Although ionomers are useful in many applications, ionomers have limited service temperatures, which limits the use of ionomers in applications requiring creep resistance at temperatures above 60 ℃. For example, ionomers may deform under stress at temperatures above 60 ℃. Dynamic mechanical thermal analysis indicated a substantial decrease in mechanical strength of the ionomer at about 60 ℃, which was associated with the onset of ionic aggregate dissociation.
Disclosure of Invention
Accordingly, it may be beneficial to develop alternative ionomers having improved creep resistance while maintaining the physical and chemical properties of the ionomer (e.g., optical clarity and toughness).
In embodiments, the ionomers of the present disclosure include a neutralized blend of an ethylene acid copolymer and an aliphatic monofunctional organic acid. The blend comprises 60 to 95 wt.% of the ethylene acid copolymer, based on the total wt.% of the blend; and 5 to 40 wt.%, based on the total wt.% of the blend, of the aliphatic monofunctional organic acid, wherein the aliphatic monofunctional organic acid has less than 36 carbon atoms. At least 30 mole% of the total acid units of the blend are neutralized with the magnesium cations of the magnesium neutralization salt. The ethylene acid copolymer in the blend comprises the polymerization reaction product of: ethylene, 1 to 40 wt.% alkyl acrylate, based on the total wt.% of monomers present in the ethylene acid copolymer, 2 to 15 wt.% unsaturated dicarboxylic acid monomer, based on the total wt.% of monomers present in the ethylene acid copolymer, and optionally 0 to 20 wt.% monocarboxylic acid monomer, based on the total wt.% of monomers present in the ethylene acid copolymer.
In one or more embodiments, the ionomers of the present disclosure include a neutralized blend of a first ethylene acid copolymer, a second ethylene acid copolymer, and an aliphatic monofunctional organic acid, where the aliphatic monofunctional organic acid has fewer than 36 carbon atoms. The ratio of the first ethylene acid copolymer to the second ethylene acid copolymer in the blend is 90/10 wt.% to 10/90 wt.%; and 5 to 40 wt.%, based on the total wt.% of the blend, of the aliphatic monofunctional organic acid and at least 30 mole% of the total acid units of the blend are neutralized with the magnesium cations of the magnesium neutralization salt.
In one or more embodiments of the blend, the first ethylene acid copolymer of the blend is the polymerization reaction product of: ethylene; 2 to 20 wt.%, based on the total wt.% of monomers present in the first ethylene acid copolymer, of monocarboxylic acid monomers; and 0 to 40 wt.% alkyl acrylate, based on the total wt.% of monomers present in the first ethylene acid copolymer.
In various embodiments of the blend, the second ethylene acid copolymer is the polymerization reaction product of: ethylene; 1 to 40 wt.% alkyl acrylate, based on the total wt.% of monomers present in the second ethylene acid copolymer; 0 to 20 wt.% monocarboxylic acid monomers, based on the total wt.% of monomers present in the second ethylene acid copolymer; and 2 to 15 wt.% of unsaturated dicarboxylic acid monomers, based on the total wt.% of monomers present in the second ethylene acid copolymer.
Detailed Description
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. In case of conflict, the present specification, including definitions, will control.
Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of various embodiments, suitable methods and materials are described herein.
All percentages, parts, ratios, etc., are by weight unless otherwise indicated. When an amount, concentration, or other value or parameter is given as either a range, preferred range, or a list of lower preferable values and higher preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any lower limit or lower preferable value and any upper limit or higher preferable value for the range, regardless of whether ranges are separately disclosed. Where a range of numerical values is recited herein, unless otherwise stated, the range is intended to include the endpoints thereof, and all integers and fractions within the range. When defining a range, it is not intended that the scope of the invention be limited to the specific values recited.
When the term "about" is used to describe a value or range endpoint, the disclosure should be understood to include the specific value or endpoint referred to.
As used herein, the terms "comprises," "comprising," "includes," "including," "contains," "characterized by," "has/having," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to those elements, and may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Further, unless expressly stated to the contrary, "or" means an inclusive or and not an exclusive or.
The transitional phrase "consisting essentially of … …" limits the scope of the claims to the specified materials or steps and those materials or steps that do not materially affect one or more of the basic and novel features of the disclosure. Where applicants have defined an embodiment, or a portion thereof, using open-ended terms such as "comprising," the description should be construed as also using the term "consisting essentially of … … to describe such embodiment, unless otherwise noted.
The use of "a" or "an" is employed to describe elements and components of various embodiments. This is for convenience only and to give a general sense of the various embodiments. This description should be read to include one or at least one and the singular also includes the plural unless it is obvious that it is meant otherwise.
The term "polymer" refers to a polymeric compound prepared by polymerizing monomers of the same or different types. The generic term polymer thus embraces the terms "homopolymer" and "copolymer". The term "homopolymer" refers to a polymer prepared from only one type of monomer. The term "copolymer" refers to a polymer prepared from two or more different monomers, and for purposes of this disclosure, may include "terpolymers" and "interpolymers".
The term "monocarboxylic acid monomer" means a molecule having a reactive moiety (e.g., a vinyl or vinylidene group) that can bond to other monomers to form a polymer and carboxylic acid (-c (o) OH) moieties not included in the reactive moiety. For example, (meth) acrylic acid is a monocarboxylic acid monomer in which a vinylidene group is the reactive moiety and a carboxylic acid is present. The term "(meth) acrylic" includes methacrylic and/or acrylic, and "(meth) acrylate" includes methacrylate, acrylate, or a combination of methacrylate and acrylate.
The term "unsaturated dicarboxylic acid monomer" as used in this disclosure means a molecule having a reactive moiety (such as a vinyl or vinylidene group) that can bond to other monomers to form a polymer and two carboxylic acid (-c (o) OH) groups that are not included in the reactive moiety. In addition, "unsaturated dicarboxylic acid monomer" includes unsaturated dicarboxylic acid derivative monomers (half esters and anhydrides).
Various embodiments relate to ionomers comprising neutralized blends of ethylene acid copolymers and aliphatic monofunctional organic acids. In one or more embodiments, the neutralized blend may include the ethylene acid copolymer in an amount of 60 to 95 wt.%, based on the total weight% (wt.%) of the blend, and the aliphatic monofunctional organic acid in an amount of 5 to 40 wt.%, based on the total wt.% of the blend. In some embodiments, the ionomer comprises a neutralized blend of an ethylene acid copolymer and an aliphatic monofunctional organic acid, wherein the amount of ethylene acid copolymer is 65 to 80 wt.%, 70 to 85 wt.%, or 70 to 80 wt.%. In some embodiments, the aliphatic monofunctional organic acid is 10 to 40 wt.%, 15 to 40 wt.%, or 20 to 40 wt.%.
In some embodiments, at least 30 mole percent (mol%) of the total acid units of the blend are neutralized with the magnesium cations of the magnesium neutralization salt. In some embodiments, 35 to 50 mol%, 45 to 70 mol%, 60 to 80 mol%, or 80 to 100 mol% of the total acid units of the blend are neutralized with the magnesium cations of the magnesium neutralization salt.
In some embodiments, the ionomer may include cations other than magnesium cations and other than magnesium cations in the blend. The blend may be neutralized with at least one additional metal cation of a neutralizing salt. The neutralizing salt of the at least one additional metal cation may be selected from the group of zinc, lithium and sodium salts. In some embodiments, the ionomer may include 0% to 10%, 1% to 10%, 5% to 20%, 5% to 30%, or 10% to 50% of the total acid units of the blend neutralized with sodium cations of a neutralizing salt, lithium cations of a neutralizing salt, zinc cations of a neutralizing salt, or a combination thereof. In one or more embodiments, at least 70 mole% of the total acid units of the blend are neutralized with the metal cations of the neutralizing salt, wherein at least 30 moles of the total acid units present in at least 70 mole% of the blend are neutralized with the magnesium cations of the magnesium salt.
In one or more embodiments, the ethylene acid copolymer includes the polymerization product of ethylene, alkyl acrylate, monocarboxylic acid monomers, unsaturated dicarboxylic acid monomers. In some embodiments of the ethylene acid copolymer of the blend, the alkyl acrylate may be present in an amount of 1 to 40 wt.%, based on the total wt.% of the monomers present in the ethylene acid copolymer. All individual values and subranges encompassed by "1 wt.% to 40 wt.% are disclosed as separate embodiments. The ethylene acid copolymer can include, for example, 1 to 20 wt.% alkyl acrylate, 2 to 10 wt.% or 10 to 30 wt.% alkyl acrylate, based on the total wt.% of the monomers present in the ethylene acid copolymer.
In various embodiments of the ethylene acid copolymer, the monocarboxylic acid monomer can be optional and present in an amount of 0 to 20 wt.%. All individual values and subranges encompassed by "0 wt.% to 20 wt.% are disclosed as separate embodiments. For example, monocarboxylic acid monomers can be absent or present in an amount of greater than 0 wt.% to 10 wt.%, 5 wt.% to 10 wt.%, 10 wt.% to 20 wt.%, or 15 wt.% to 20 wt.%, based on the total weight of monomers present in the ethylene acid copolymer.
In one or more embodiments of the ethylene acid copolymer, the unsaturated dicarboxylic acid monomer can be present in an amount of 2 wt.% to 15 wt.%, based on the total wt.% of monomers present in the ethylene acid copolymer. All individual values and subranges encompassed by "2 wt.% to 15 wt.% are disclosed as separate embodiments. For example, the unsaturated dicarboxylic acid monomer can be present in an amount of 5 wt.% to 15 wt.%, 3 wt.% to 10 wt.%, or 4 wt.% to 10 wt.%, based on the total weight of monomers present in the ethylene acid copolymer.
In embodiments of the ionomers of the present disclosure, the ionomer can include a blend of two ethylene acid copolymer resins, a first ethylene acid copolymer polymer, and a second ethylene acid copolymer. One of the first ethylene acid copolymer or ethylene acid copolymer polymer contains an unsaturated dicarboxylic acid monomer.
In various embodiments, the ionomers of the present disclosure can include a neutralized blend of a first ethylene acid copolymer, a second ethylene acid copolymer, and an aliphatic monofunctional organic acid. The first ethylene acid copolymer is the polymerization reaction product of ethylene, a monocarboxylic acid monomer, and optionally an alkyl acrylate. The second ethylene acid copolymer is the polymerization reaction product of ethylene, an alkyl acrylate, an unsaturated dicarboxylic acid monomer, and optionally a monocarboxylic acid monomer. In some embodiments, at least 30 mole percent (mol%) of the total acid units of the blend are neutralized with the magnesium cations of the magnesium neutralization salt. In one or more embodiments, 35 to 50 mol%, 45 to 70 mol%, 60 to 80 mol%, or 80 to 100 mol% of the total acid units of the blend are neutralized with the magnesium cations of the magnesium neutralization salt.
In some embodiments, the ionomers of the present disclosure that include a neutralized blend of a first ethylene acid copolymer, a second ethylene acid copolymer, and an aliphatic monofunctional organic acid can include cations other than magnesium cations and other than magnesium cations in the blend. The blend may be neutralized with at least one additional metal cation of a neutralizing salt. The neutralizing salt of the at least one additional metal cation may be selected from the group of zinc, lithium and sodium salts. In some embodiments, the ionomer may include 0% to 10%, 1% to 10%, 5% to 20%, 5% to 30%, or 10% to 50% of the total acid units of the blend neutralized with sodium cations of a neutralizing salt, lithium cations of a neutralizing salt, zinc cations of a neutralizing salt, or a combination thereof. In one or more embodiments, at least 70 mole% of the total acid units of the blend are neutralized with the metal cations of the neutralizing salt, wherein at least 30 moles of the total acid units present in at least 70 mole% of the blend are neutralized with the magnesium cations of the magnesium salt.
In one or more embodiments, the ratio of the first ethylene acid copolymer to the second ethylene acid copolymer in the blend is from 90/10 wt.% to 10/90 wt.%, based on the total wt.% of the blend; and the amount of aliphatic monofunctional organic acid in the blend is from 5 to 40 wt.%. In some embodiments, the ratio of the first ethylene acid copolymer to the second ethylene acid copolymer in the blend is from 50/50 wt.% to 80/20 wt.% or from 90/10 wt.% to 60/40 wt.%.
In various embodiments, the ionomers of the present disclosure can include a neutralized blend of a first ethylene acid copolymer, a second ethylene acid copolymer, and an aliphatic monofunctional organic acid. In one or more embodiments, the first ethylene acid copolymer is the polymerization reaction product of: ethylene; 2 to 20 wt.% or 5 to 10 wt.% monocarboxylic acid monomer, based on the total wt.% of monomers present in the first ethylene acid copolymer; 0 to 40 wt.%, 1 to 20 wt.%, or 5 to 15 wt.% alkyl acrylate, based on the total wt.% of monomers present in the first ethylene acid copolymer.
In one or more embodiments, the second ethylene acid copolymer is the polymerization reaction product of ethylene, an alkyl acrylate, optionally a monocarboxylic acid monomer, and an unsaturated dicarboxylic acid monomer. The alkyl acrylate may be present in an amount of 1 wt.% to 40 wt.%, 5 wt.% to 30 wt.%, 10 wt.% to 20 wt.%, or 20 wt.% to 30 wt.%, based on the total wt.% of monomers present in the second ethylene acid copolymer. The monocarboxylic acid monomers can be present in an amount of 0 wt.% to 20 wt.%, 1 wt.% to 20 wt.%, 5 wt.% to 15 wt.%, based on the total wt.% of monomers present in the second ethylene acid copolymer. The unsaturated dicarboxylic acid monomer can be present in the second ethylene acid copolymer in an amount of 2 to 15 wt.%, or 5 wt.% to 10 wt.%, based on the total wt.% of monomers present in the second ethylene acid copolymer.
In some embodiments of the ethylene acid copolymer, the first ethylene acid copolymer, or the second ethylene acid copolymer, the alkyl acrylate can be, for example, but not limited to, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, or a combination thereof. In various embodiments, the alkyl acrylate has an alkyl group having 1 to 8 carbons. It is designated as C2-C8-alkyl acrylates. In a particular embodiment, the alkyl acrylate is n-butyl acrylate.
In one or more embodiments of the ethylene acid copolymer, the first ethylene acid copolymer, or the second ethylene acid copolymer, the monocarboxylic acid monomers can include, for example, one or more of acrylic acid, methacrylic acid, or a combination thereof.
In one or more embodiments of the ethylene acid copolymer or the second ethylene acid copolymer, the unsaturated dicarboxylic acid monomer comprises a reaction product of a precursor acid copolymer that is an unsaturated dicarboxylic acid or a derivative of an unsaturated dicarboxylic acid. The unsaturated dicarboxylic acid monomer may include monoethyl maleate (MAME), monopropyl maleate, monoethyl maleate, monobutyl maleate, or combinations thereof; and C of these acids1-C4Alkyl half esters, and anhydrides of these acids (including maleic anhydride, monomethyl maleic anhydride, monoethyl maleic anhydride, and itaconic anhydride). The carboxylic acid or anhydride units of these monomers can be neutralized with metal ions, as with monocarboxylic acid units, but as indicated, the neutralization of unsaturated dicarboxylic acid monomers can differ in their properties and impact on polymer properties, including melt behavior. The unsaturated dicarboxylic acid can dehydrate to form intra-chain anhydride units within the polymer (i.e., form within the chain, rather than form cross-linked inter-chain anhydride units).
In various embodiments described in the present disclosure, the ionomer is a Fatty Acid Modified Ionomer (FAMI). Specifically, according to various embodiments, the ethylene acid copolymer is blended with an aliphatic monofunctional organic acid. In one or more embodiments, the aliphatic monofunctional organic acid has fewer than 36 carbon atoms. In some embodiments, the aliphatic monofunctional groupThe organic acid comprises a fatty acid having from 4 to 36 carbon atoms, and optionally one to three independently selected from C1To C8Alkyl groups. For example, the aliphatic monofunctional organic acid may comprise C4To less than C36E.g. C34、C4-26、C6-22Or C12-22Or a salt thereof. The fatty acid comprises at least one of behenic acid, stearic acid, oleic acid, erucic acid, 12-hydroxystearic acid, and isostearic acid. At high neutralization levels (e.g., greater than 80% to 100%), nominal neutralization levels (e.g., sufficient metal compound is added to cause nominal neutralization of all acid moieties in the aliphatic monofunctional organic acid and copolymer in the blend), volatility is not an issue, and aliphatic monofunctional organic acids with lower carbon content can be used. In some embodiments, the aliphatic monofunctional organic acid (or salt) is non-volatile (non-volatile at the melt blending temperature of the reagent and acid copolymer) and non-migratory (does not accumulate to the polymer surface under normal storage conditions (ambient temperature)).
Ionomers of the present disclosure include neutralized blends of an ethylene acid copolymer and an aliphatic monofunctional organic acid or neutralized blends of a first ethylene acid copolymer, a second ethylene acid copolymer, and an aliphatic monofunctional organic acid. The term "neutralized blend" includes fully or partially neutralized ethylene acid copolymers. The ethylene acid copolymer may contain neutralized and unneutralized monocarboxylic acid units, neutralized, mononeutralized and unneutralized unsaturated dicarboxylic acid units, and intrachain anhydride units.
With respect to the total acid units neutralized, monocarboxylic acids provide one acid unit, dicarboxylic acids provide two acid units, anhydrides such as maleic anhydride are considered to provide two acid units, and half-esters are considered to provide one acid unit. The percent neutralization is calculated based on the number of acid units considered above to be present and the number of metal equivalents added. In fact, the anhydride units may remain as anhydride units rather than becoming acid units. When subjected to neutralization, the anhydride monomer units may form di-metal salts, mono-metal salts, form non-neutralized dicarboxylic acid monomers, or leave the anhydride units unchanged as anhydride units, as if they had no acid functionality. Half esters of dicarboxylic acid monomers, while counted as having only one acid, can actually be converted to dicarboxylic acid monomers or anhydrides, and there are various possibilities mentioned above in connection with neutralization. However, as stated, the calculated percent neutralization is based on the number of acid units based on the known molar amounts of monocarboxylic and dicarboxylic acid comonomers, no matter how many acid groups are actually present (free or neutralized). In view of the variety of dicarboxylic acid monomers and possible salts, the actual percentage of neutralized acid groups (i.e., the percentage of actual total neutralized and unneutralized free acid groups) can thus be different from the calculated percent neutralization based on the amount of monocarboxylic acid monomer or dicarboxylic acid monomer in the ionomer. The difference is due to the anhydride unit, which is not an acid unit, but is counted as two acid units.
Ethylene acid copolymers can be prepared by standard free radical copolymerization processes, using high pressures, operating in a continuous manner. The monomers are fed to the reaction mixture in a ratio which is related to the reactivity of the monomers and the desired incorporation. In this way, a uniform, nearly random distribution of monomer units along the chain is achieved. The unreacted monomer can be recovered. Additional information regarding the preparation of ethylene acid copolymers including softening monomers can be found in U.S. Pat. No. 3,264,272 and U.S. Pat. No. 4,766,174, each of which is incorporated herein by reference in its entirety.
The blend may be produced by any means known to those skilled in the art. It is substantially melt processable and can be produced by combining one or more ethylene acid copolymers or ionomers of ethylene acid copolymers, one or more fatty acids or salts thereof, a basic metal compound, and a neutralizing composition comprising a trivalent metal cation to produce a mixture, and heating the mixture under conditions sufficient to produce the composition. The heating may be carried out at a temperature in the range of 80 ℃ to 350 ℃, 120 ℃ to 300 ℃, or 160 ℃ to 260 ℃ at a pressure that accommodates the temperature for a period of 30 seconds to 2 or 3 hours. The blend can be produced by melt blending the ethylene acid copolymer and/or ionomer thereof with one or more fatty acids or salts thereof and simultaneously or subsequently combining a sufficient amount of the basic metal compound and the trivalent metal cation. Salt blends of the components can be prepared or the components can be melt blended in an extruder. For example, the ethylene acid copolymer and aliphatic monofunctional organic acid (or salt) can be simultaneously mixed and processed with the metal compound using a Werner & Pfleiderer twin screw extruder.
The blend may additionally include minor amounts of additives including plasticizers, stabilizers (including viscosity stabilizers, hydrolytic stabilizers), primary and secondary antioxidants, ultraviolet light absorbers, antistatic agents, dyes, pigments or other colorants, inorganic fillers, flame retardants, lubricants, reinforcing agents (glass fibers and glass flakes), synthetic (e.g., aramid) fibers or pulps, foaming or blowing agents, processing aids, slip additives, antiblocking agents (e.g., silica or talc), mold release agents, tackifying resins, or combinations of two or more thereof. Inorganic fillers such as calcium carbonate may also be incorporated into the blend.
These additives may be present in the blend in an amount in the range of 0.01 to 40, 0.01 to 25, 0.01 to 15, 0.01 to 10, or 0.01 to 5 weight percent. Incorporation of the additives can be carried out by any known method, such as, for example, by dry blending, by extruding a mixture of the various ingredients, by conventional masterbatch techniques, and the like.
In one or more embodiments, the ionomers of the present disclosure have a melt index of 0.1 to 10.0 grams/10 minutes as determined according to ASTM D1238(210 ℃, 2.16 kg). In other embodiments, the ionomer has a melt index of 1.0 to 10.0 grams/10 minutes as determined according to ASTM D1238(210 ℃, 2.16 kg). Additionally, in some embodiments of the present disclosure, the ionomer has a density of 0.920 to 0.980g/cc as measured according to ASTM D792.
In some embodiments, the ionomers according to the present disclosure exhibit load bearing capacity at temperatures above the melting temperature of the ionomer, as measured by Differential Scanning Calorimetry (DSC).
According to various embodiments, the ionomer may be used to form a foam or molded article. For example, in embodiments, the ionomer may be combined with additives for controlling foam properties to form foams of various shapes. In some embodiments, the foam may be extruded, for example, from a twin screw extruder, as known to one of ordinary skill in the art.
The blowing agent (also referred to as a blowing agent) used to make the foam may be a physical blowing agent or a chemical blowing agent. As used herein, a "physical blowing agent" is a low boiling liquid that volatilizes under curing conditions to form a blowing gas. Exemplary physical blowing agents include hydrocarbons, fluorocarbons, hydrofluorocarbons, hydrofluoroolefins, hydrochlorofluoroolefins, and other halogenated compounds. Other suitable chemical blowing agents may include, for example, sodium bicarbonate, ammonium bicarbonate, azodicarbonamide, dinitrosopentamethylenediamine, and sulfonyl hydrazide. Blowing agents added in gaseous or liquid form, such as water or carbon dioxide, or generated in situ by the reaction of water with the polyisocyanate may also be used. The blowing agent may be used in the form of a mixture of two or more, and chemical and physical blowing agents may be used together to adjust the expansion-decomposition temperature and the foaming process.
The foam composition may further include a free radical initiator or cross-linking agent, a co-curing agent, an activator, and any other type of additive typically used in similar compositions, including but not limited to pigments, adhesion promoters, fillers, nucleating agents, rubbers, stabilizers, and processing aids.
The free radical initiator or crosslinking agent may include, for example, but is not limited to, organic peroxides, such as dialkyl organic peroxides. Suitable example organic peroxides include 1, 1-di-tert-butylperoxy-3, 3, 5-trimethylcyclohexane, tert-butylcumyl peroxide, dicumyl peroxide, 2, 5-dimethyl-2, 5-di (tert-butyl-peroxy) hexane, 1, 3-bis (tert-butyl-peroxy-isopropyl) benzene, or a combination of two or more thereof.
The co-curing agent comprises trimethylpropane triacrylate (and similar compounds), N-m-phenylene bismaleimide (N, N-m-phenylene bismaleimide), triallyl cyanurate, or a combination of two or more thereof.
The activator may comprise an activator for the blowing agent and may comprise one or more metal oxides, metal salts or organometallic complexes. Examples include ZnO, zinc stearate, MgO, or a combination of two or more thereof.
Foams can be produced by a variety of methods, such as compression molding, injection molding, and a mixture of extrusion and molding. The method may include mixing the components of the foam composition under heat to form a melt. The components may be mixed and blended using any technique known and used in the art, including Banbury (Banbury) machines, intensive mixers, twin roll mills, and extruders. The time, temperature and shear rate can be adjusted to ensure dispersion without premature crosslinking or foaming.
After mixing, shaping can be performed. Sheeting rolls or calendering rolls can be used to prepare the sheet in the appropriate size for foaming. An extruder may be used to shape the composition into pellets.
Foaming can be carried out in a compression mold at a temperature and time to complete decomposition of the peroxide and blowing agent. The pressure, molding temperature and heating time can be controlled. Foaming can be carried out using injection molding equipment by using pellets made from the foam composition. The resulting foam may be further formed into finished dimensions by any means known and used in the art, including thermoforming and compression molding.
In various embodiments, the resulting polymer foam composition may be substantially closed cell and suitable for use in a variety of articles of manufacture, such as footwear applications including midsoles or insoles.
In embodiments, the molded article exhibits improved creep resistance of at least 80 ℃, wherein the molded article exhibits a dimensional change of less than 25%, less than 20%, less than 18%, or less than 15% at a stress of 20psi, 80 ℃ for 30 minutes.
The ionomers of the present invention can be prepared by standard neutralization techniques, as disclosed in U.S. Pat. No. 3,264,272 (Rees), which is incorporated herein by reference. The resulting ionomer (i.e., the composition of the present invention) may have a MI of 0.01 to 100 grams/10 minutes, preferably 0.1 to 30 grams/10 minutes, as determined according to ASTM D1238(190 ℃, 2.16 kg). As defined in the preceding paragraph, the total percentage of neutralization is about 5 to 90%, preferably 10 to 70%, most preferably between 25 and 60%. While lower neutralization levels will provide less ionomer characteristics, higher levels will result in lower flow ionomers.
Examples of the invention
Test program
Melt Index (MI) was measured using ASTM D-1238 with a 2160 gram weight.
Melting points (Tm) were measured using Differential Scanning Calorimetry (DSC). Differential Scanning Calorimetry (DSC) measurements were performed on a TA Instruments Q1000 DSC equipped with an RCS cooling accessory and an autosampler. Melting point (Tm) of the samples was measured according to ASTM D3418.
The composition of the ionomer was determined using Fourier Transform Infrared Spectroscopy (FTIR) from Perkin Elmer (Perkin Elmer). A 5 mil thick compression molded film was used for FTIR analysis.
The following examples are provided to illustrate various embodiments and are not intended to limit the scope of the claims. All parts and percentages are by weight unless otherwise indicated. The following provides approximate characteristics, features, parameters, and the like with respect to various working examples, comparative examples, and substances used in the working and comparative examples. Further, the description of the raw materials used in the examples is as follows:
comparative example C1 is a magnesium ionomer of a blend of 65 wt% ethylene acid copolymer and 35 wt% oleic acid. The ethylene acid copolymer comprises ethylene, 6.2 wt% acrylic acid, and 28.0 wt% n-butyl acrylate, and has an MI of 60 to 300 grams/10 minutes as determined according to ASTM D1238(190 ℃, 2.16kg), wherein nominally 100% of the total acid units of the neutralized blend of ethylene copolymer and oleic acid are neutralized with Mg cations. Mg (OH)2As a source of Mg cations for neutralization, in an amount of 145% of all carboxylic acid moieties.
Comparative example C2 was a Mg ionomer derived from a blend of 65 wt.% ethylene copolymer and 22.5 wt.% erucic acid, where the acid copolymer was an ethylene/acrylic acid/n-butyl acrylate terpolymer having 6.2 wt.% acrylic acid and 28.0 wt.% n-butyl acrylate,and an MI of 85 g/10 min, as determined according to ASTM D1238(190 ℃, 2.16kg), wherein nominally 100% of the available carboxylic acid moieties of both the ethylene copolymer and oleic acid are neutralized with Mg cations. Mg (OH)2As a source of Mg cations for neutralization, in an amount of 120% of all carboxylic acid moieties.
Comparative example C3 is an ionomer of a zinc ion partially neutralized ethylene acid copolymer comprising 85 wt.% ethylene and 15 wt.% Methacrylate (MAA) having a density of 0.950g/cm, measured according to ASTM D7923And a melt index I as determined according to ASTM D1238(190 ℃, 2.16kg)2It was 0.7 g/10 min.
Comparative example C4 is an ionomer of an ethylene acid copolymer comprising 85 wt.% ethylene and 15 wt.% Methacrylate (MAA) partially neutralized with sodium ions, having a density of 0.950g/cm, measured according to ASTM D7923And a melt index I as determined according to ASTM D1238(190 ℃, 2.16kg)2It was 0.9 g/10 min.
Creep resistance data are shown in tables 1, 2 and 3. Creep testing was performed by measuring the dimensional change (vertical) of a compression molded film attached to a static load in a heated oven. The tests included the variables as creep resistance varied with time, temperature and load (stress).
Creep resistance varies with time, temperature and weight (stress) load. A simple test was used to distinguish the creep resistance of ionomers neutralized with and without MAME with various metal cations with and without unsaturated dicarboxylic acid comonomer MAME. Creep testing was performed by measuring the dimensional change (perpendicularity) of a film sample attached to a static load in a cross-flow air oven with a rack to hold the sample holder. Creep testing was performed on 10 mil thick, 1 inch wide, and 3 inch long strips of compression molded film cut from 10 mil thick compression molded film. The film was suspended on the sample holder with a static load of 200 grams and the oven was initially set to a temperature.
EXAMPLE 1 creep resistance of ethylene acid copolymers containing dicarboxylic acid monomers
The results as summarized in table 1 include data derived from inventive example 1 and comparative example C1, the compositions of which are as previously described.
The copolymer composition in example 1 is a blend of a first ethylene acid copolymer, a second ethylene acid copolymer, and an aliphatic monofunctional organic acid. Example 1 is a blend of 80 wt% of a first ethylene acid copolymer and (b)20 wt% of a second ethylene acid copolymer. First ethylene acid copolymer, comparative example C1. The second divinyl acid copolymer, the E/iBA/MAME terpolymer, included 10% by weight isobutyl acrylate and 12% by weight MAME. The Melt Index (MI) of the E/iBA/MAME terpolymer was 95 grams/10 minutes, measured according to ASTM D1238 using 2160 grams and at 190 ℃.
Example 1 was prepared in a Haake Rheocord 90 melt mixer at a temperature of about 210 ℃ for 5 minutes at 150 rpm. Using 2160 grams and measured at 210 ℃, the melt index of example 1 was 1.0 grams/10 minutes, as measured according to ASTM D1238.
The results of the creep test as outlined in table 1 were generated by measuring the dimensional change (vertical) of the film samples attached to a static load in a cross-flow air oven with a rack to hold the sample holder. Creep testing was performed on 10 mil thick, 1 inch wide, and 3 inch long strips of compression molded film cut from 10 mil thick compression molded film. The film was suspended on the sample holder with a static load of 200 grams and the oven was initially set to a temperature. The deformation of the film samples after the specified times and temperatures indicated in table 1 in the oven was measured.
Table 1: dimensional change at a static load of 200 g (%)
The creep resistance of the two polymer samples is summarized in table 1. Creep resistance was measured over a 24 hour period at the following varying temperatures: room temperature (about 22.0 ℃), 40 ℃, 50 ℃, 60 ℃, 70 ℃ and 80 ℃. Comparative example C1, an ionomer that did not contain unsaturated dicarboxylic acid monomers, deformed between 40 ℃ and 50 ℃. In contrast, example 1, an ionomer containing an unsaturated dicarboxylic acid MAME, showed less deformation at a temperature of 80 ℃. In contrast, example 1, an ionomer containing an unsaturated dicarboxylic acid MAME, exhibited much less distortion between 40 ℃ and 50 ℃.
Example 2 creep resistance of ethylene acid copolymers containing aliphatic monofunctional organic acids
The results as summarized in table 2 include data derived from inventive example 2. Example 2 is a blend of a first ethylene acid copolymer and a second ethylene acid copolymer. Example 2 included 70 wt.% of a first ethylene acid copolymer (comparative example C1) and (b)30 wt.% of a second ethylene acid copolymer, an E/iBA/MAME terpolymer that included 10 wt.% iBA and 12 wt.% MAME and had an MI of 95 grams/10 minutes as measured at 190 ℃.
Example 2 was prepared in a Haake Rheocord 90 melt mixer at a temperature of about 210 ℃ for 6 minutes at 150 rpm. The melt index of example 2 was 0.9 grams/10 minutes as measured according to ASTM D1238 using 2160g and measured at 210 ℃.
Table 2: dimensional change at a static load of 110 g (%)
Comparative example C3
Comparative example C4
Example 2
50℃
0.00％
0.00％
0.00％
60℃
0.00％
0.00％
0.00％
70℃
0.00％
0.00％
0.00％
80℃
12.50％
6.30％
0.00％
90℃
Fail to work
112.50％
12.50％
100℃
--
Fail to work
25.00％
120℃
62.50％
The creep resistance of the three examples is summarized in table 2. Creep testing was performed on 10 mil thick, 1 inch wide, and 3 inch long strips of compression molded film cut from 10 mil thick compression molded film. The film was suspended with a static load of 110 grams and the oven was initially set at 50 ℃. The percent deformation of the film sample was measured after 30 minutes in the oven, and the oven temperature was then increased by 10 ℃. The temperatures measured were 50 deg.C, 60 deg.C, 70 deg.C, 80 deg.C, 90 deg.C, 100 deg.C and 120 deg.C. Comparative examples C1-C2, i.e., no unsaturated dicarboxylic acid monomer or aliphatic monofunctional organic acid ("fatty acid"), ionomers that failed at 90 ℃ and 100 ℃. Comparative example C4 is an ionomer containing fatty acid salts and no unsaturated dicarboxylic acids. Comparative example C4 did not pass the creep test, but deformed 750.0%. In contrast, example 2, an ionomer containing dicarboxylic acid MAME and fatty acid, exhibited less distortion in the temperature range of 80 ℃ to 100 ℃ compared to the comparative sample.
Example 3 creep resistance of ethylene acid copolymer containing two Polymer resins and aliphatic monofunctional organic acid
The results as summarized in table 3 include data derived from inventive examples 3-7. The copolymer compositions in examples 3-7 are reported in Table 3. Examples 3, 4, 5, 6 and 7 were prepared in a 26mm twin screw extruder with mixing screws using melt temperatures between 220 ℃ and 250 ℃.
Example 3 is a blend of 80 wt.% comparative example C1 and 20 wt.% of an ethylene/isobutyl acrylate/monoethyl maleate (E/iBA/MAME) terpolymer in which 10 wt.% iBA and 12 wt.% MAME are present and which has an MI of 95 g/10 min measured according to ASTM D1238 using 2160g and at 190 ℃.
Examples 4, 5 and 6 include blends of comparative example C1 and an E/iBA/MAME terpolymer, as summarized in table 3 below. The E/iBA/MAME terpolymer had 15 wt.% iBA and 12 wt.% MAME and an MI of 173 g/10 minutes as measured at 190 ℃ according to ASTM D1238 using 2160 grams. For each example, the weight percent of comparative example C1 and the percent of terpolymer are reported in table 3.
Example 7 was 80 wt.% of a blend of comparative example C2 and an E/nBA/MAME terpolymer having 15 wt.% iBA and 12 wt.% MAME, and the MI of the terpolymer was 173 grams/10 minutes as measured according to ASTM D1238 using 2160 grams at 190 ℃.
Comparative example C1 is the same composition as described above.
Comparative example C2 is the same composition as described above.
Table 3: creep temperature at 25% dimensional change
Composition numbering
Ionomer composition
Temperature of creep
Example 3
Comparative example C1, 80 wt.%, E/nBA/MAME, 20wt. -%)
90℃
Example 4
Comparative example C1, 80 wt.%, E/iBA/MAME, 20wt. -%)
90℃
Example 5
Comparative example C1, 75 wt.%, E/iBA/MAME, 25wt. -%)
100℃
Example 6
Comparative example C1, 70 wt.%, E/iBA/MAME, 30wt. -%)
100℃
Example 7
Comparative example C2, 80 wt.%, E/nBA/MAME 20wt. -%)
100℃
Comparative example C1
60℃
Comparative example C2
60℃
In table 3, the creep temperature of each sample was measured when the sample exhibited a 25% dimensional change. Each of polymer resin examples 3-7, which contained unsaturated dicarboxylic acid monomers (MAME), exhibited creep resistance about 30-40 ℃ higher than that of comparative example C1.