Environmentally friendly processing aids based on oligomeric hindered amines

Abstract

The invention relates to the use of oligomeric hindered amines for improving the flow properties of a melt comprising a thermoplastic polymer; and a method for improving the flow properties of a melt comprising a thermoplastic polymer, the method comprising the step of incorporating oligomeric hindered amines into the thermoplastic polymer prior to or during melt processing, wherein the thermoplastic polymer is free of polymer processing aids.

Description

[0001] This invention relates to the use of hindered oligomeric amines for improving the flow properties of melts containing thermoplastic polymers; and to a method for improving the flow properties of melts containing thermoplastic polymers, the method comprising the step of incorporating a hindered oligomeric amine into the thermoplastic polymer before or during melt processing, wherein the thermoplastic polymer is free of polymer processing aids.

[0002] The flow characteristics of polymer melts are crucial to the design and operating conditions of industrial processing equipment and can significantly influence the overall properties of the manufactured polymer products. Polymer melts typically exhibit non-Newtonian behavior; that is, their apparent viscosity is strongly dependent on the shear rate applied when processing the polymer at temperatures well above its melting point. High shear rates typically result from the high levels of mechanical energy (pressure and shear) applied during molding processes for extrusion, feeding, or any type of conveying of the polymer melt. Furthermore, high shear rates can also result from high flow rates or velocities when the polymer melt is forced through narrow dies, nozzles, cylindrical profiles, etc., which can be circular, rectangular, annular, slit-shaped, or any other irregular shape or low-gap-width cross-section.

[0003] If sufficient attention is not paid to the specific rheological properties of polymer melts, this can ultimately lead to several negative and therefore undesirable consequences in terms of the polymer's aesthetic or mechanical properties. These consequences are well-known in extrusion processes, particularly in the manufacture of profiles, especially thin-walled profiles, cast or blown films. Various defects are commonly referred to as sharkskin, snakeskin, or orange peel. These terms are metaphorical and self-explanatory descriptions of melt fracture phenomena that become increasingly apparent at high shear rates, causing visible roughness or even cracks and fissures on the polymer surface, resulting in severe degradation of the optical and mechanical properties of the manufactured polymer articles.

[0004] Specific cases involve polyolefins, including linear polyethylene, such as linear low-density polyethylene (LLDPE), a widely used commercial polymer, but known to have difficult melt processability. Several polyolefins, especially LLDPE, are prone to melt fracture (MF) due to their relatively narrow molecular weight distribution and the specific entanglement characteristics of their polymer chains.

[0005] While it is generally agreed that fluorine-based polymers incorporated into LLDPEs improve the appearance of extrudates at high output rates and reduce polymer melt viscosity, these products are also known to have several drawbacks, such as long onset times until such processing aids take effect as intended (i.e., until MF is eliminated or its occurrence is delayed to significantly higher shear rates, and / or until the energy consumption of compounding is significantly reduced at a given throughput). Purging, removal, or cleaning after processing such polymers containing fluorine-based polymers, i.e., when switching from one production run to another, is very time-consuming. Furthermore, such fluorine-based processing aids are often produced from perfluorooctanoic acid (PFOA), a precursor that appears to be very persistent in the environment and is suspected of being harmful to health.

[0006] Besides fluorine-based polymer processing aids, silicone-based polymers or polyethylene glycol, waxes, or various fatty acid esters are also known in the art. However, the benefits of such products are not always significant, as their performance at a given concentration may not be as good as that of fluorine-based polymer processing aids, and they may not show their effectiveness on all equipment. Silicone-based polymers or polyethylene glycol-based ones have additional disadvantages, such as undesirable streaks in the final product, for example, in the film, the generation of fumes, or plate out on the calendering rolls.

[0007] The aim is to overcome the aforementioned shortcomings.

[0008] This objective is achieved by using hindered oligomeric amines to improve the flow properties of melts containing thermoplastic polymers.

[0009] This objective is also achieved by a method for improving the flow properties of a melt containing a thermoplastic polymer, the method comprising the step of incorporating an oligomeric hindered amine into the thermoplastic polymer before or during melt processing, wherein the thermoplastic polymer is free of polymer processing aids, preferably free of fluorine-based polymers.

[0010] Improved flow characteristics are preferably characterized by reduced melt fracture. This reduction in melt fracture can be visually analyzed, for example, by analyzing the time until the sharkskin-like texture disappears from the surface of the melt.

[0011] The hindered oligomeric amine may have a molecular weight of at least 1000 g / mol, preferably at least 1300 g / mol, and particularly at least 1500 g / mol.

[0012] Hindered oligomeric amines can have molecular weights of up to 20,000 g / mol, up to 10,000 g / mol, and especially up to 5,000 g / mol.

[0013] The melt may contain 0.01 to 4 wt%, preferably 0.05 to 2 wt%, more preferably 0.1 to 1.5 wt%, and particularly 0.2 to 1.0 wt% of hindered oligomer amines.

[0014] hindered oligomeric amines typically comprise compounds selected from the following: compounds having formula (I).

[0015] (I)

[0016] in

[0017] b1 is a number from 1 to 20;

[0018] Group R1 is independently hydrogen, C1-C8 alkyl, or O. . -OH, -CH2CN, C1-C 18 Alkoxy, C5-C 12 Cycloalkoxy, C3-C6 alkenyl, unsubstituted or C7-C9 phenylalkyl substituted with 1, 2 or 3 C1-C4 alkyl groups on the phenyl group; or C1-C8 acyl group;

[0019] R2 is C2-C 18 Alkylene, C5-C7 cycloalkylene, or C1-C4 alkylene di(C5-C7 cycloalkylene);

[0020] R3 and R4 are independently hydrogen, C1-C 12 Alkyl, unsubstituted, or C5-C substituted with 1, 2, or 3 C1-C4 alkyl groups 12 Cycloalkyl; unsubstituted phenyl or phenyl substituted with 1, 2 or 3 C1-C4 alkyl groups; unsubstituted C7-C9 phenylalkyl or phenyl substituted with 1, 2 or 3 C1-C4 alkyl groups; or groups having formula (Ia).

[0021] (Ia)

[0022] or

[0023] R3 and R4 together with the nitrogen atoms they are attached to form 5- to 10-membered heterocycles;

[0024] and / or compounds having formula (II)

[0025] (II)

[0026] in

[0027] b2 is a number from 1 to 20;

[0028] Group X1 is independently hydrogen, C1-C8 alkyl, or O. .-OH, -CH2CN, C1-C 18 Alkoxy, C5-C 12 Cycloalkoxy, C3-C6 alkenyl, unsubstituted or C7-C9 phenylalkyl substituted with 1, 2 or 3 C1-C4 alkyl groups on the phenyl group; or C1-C8 acyl group;

[0029] Group Y1 is independently hydrogen, C1-C 12 Alkyl, unsubstituted, or C5-C substituted with 1, 2, or 3 C1-C4 alkyl groups 12 Cycloalkyl; unsubstituted or substituted phenyl groups with 1, 2 or 3 C1-C4 alkyl groups; unsubstituted or substituted C7-C9 phenylalkyl groups with 1, 2 or 3 C1-C4 alkyl groups; or groups having formula (IIa);

[0030] (IIa)

[0031] Group Z1 is independently C2-C. 18 Alkylene, C5-C7 cycloalkylene or C1-C4 alkylene di(C5-C7 cycloalkylene).

[0032] Examples of alkyl groups having up to 12 carbon atoms are methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, 2-ethylbutyl, n-pentyl, isopentyl, 1-methylpentyl, 1,3-dimethylbutyl, n-hexyl, 1-methylhexyl, n-heptyl, isoheptyl, 1,1,3,3-tetramethylbutyl, 1-methylheptyl, 3-methylheptyl, n-octyl, 2-ethylhexyl, 1,1,3-trimethyl-hexyl, 1,1,3,3-tetramethylpentyl, nonyl, decyl, undecyl, 1-methylundecyl, and dodecyl.

[0033] Examples of alkoxy groups having up to 18 carbon atoms are methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, pentoxy, isopentoxy, hexoxy, heptoxy, octoxy, decoxy, dodecoxy, tetradecoxy, hexadecoxy, and octadecoxy. A preferred group is n-propoxy.

[0034] Examples of alkenyl groups having up to 6 carbon atoms are allyl, 2-methylallyl, butenyl, pentenyl, and hexenyl. Allyl is preferred. The carbon atom at position 1 is preferably saturated.

[0035] Unsubstituted or substituted C5-C4 alkyl groups 12 Examples of cycloalkyl groups are cyclohexyl, methylcyclohexyl, and dimethylcyclohexyl.

[0036] C5-C 12Examples of cycloalkoxy groups are cyclopentoxy, cyclohexyloxy, cycloheptoxy, cyclooctoxy, cyclodecoxy, and cyclododecoxy. Cyclohexyloxy is preferred.

[0037] Examples of unsubstituted or substituted phenyl groups with 1, 2 or 3 C1-C4 alkyl groups are methylphenyl, dimethylphenyl, trimethylphenyl and tert-butylphenyl.

[0038] Examples of unsubstituted C7-C9 phenylalkyl groups or those substituted with one, two, or three C1-C4 alkyl groups on the phenyl group are methylbenzyl, dimethylbenzyl, trimethylbenzyl, and tert-butylbenzyl.

[0039] Examples of acyl groups containing no more than 8 carbon atoms are formyl, acetyl, propionyl, butyryl, valeryl, hexanoyl, heptayl, octanoyl, acrylyl, methacrylyl, and benzoyl. C1-C8 alkylyl, C3-C8 enoyl, and benzoyl are preferred.

[0040] Examples of alkylene groups having up to 18 carbon atoms are ethylene, propylene, trimethylene, tetramethylene, pentamethylene, 2,2-dimethyltrimethylene, hexamethylene, trimethylhexamethylene, and octamethylene. C2-C6 alkylene groups are preferred, especially hexamethylene.

[0041] An example of a C5-C7 cyclohexene is the cyclohexene group.

[0042] An example of C1-C4 alkylene di(C5-C7 cycloalkylene) is methylene dicyclohexylene.

[0043] Preferred examples of 5- to 7-membered heterocycles are morpholine groups.

[0044] The groups R1 and X1 are preferably hydrogen, methyl or propoxy, especially n-propoxy.

[0045] Suitable compounds for components (I) and (II) are CHIMASSORB ® 944, CHIMASSORB ® 2020, CYASORB ® UV 3346, CYASORB ® UV 3529, DASTIB ® 1082, TINUVIN ® NOR 371, TINUVIN ® NOR 356, UVASORB ® HA88 and CHIMASSORB ® 119.

[0046] Examples of compounds having formulas (I) and (II) are:

[0047]

[0048] Where b1 is a number between 2 and 10,

[0049]

[0050] Where b1 is a number from 1 to 10,

[0051]

[0052] Where R1 is hydrogen or methyl and b1 is a number from 2 to 10.

[0053]

[0054] Where b1 is a number between 2 and 10,

[0055]

[0056] Where b1 is a number from 1 to 10,

[0057]

[0058] Where b2 is a number from 2 to 10, and

[0059] .

[0060] In one form, hindered oligomeric amines include compounds having the following formula (a).

[0061] (a)

[0062] Where b1 is a number from 1 to 10.

[0063] Preferably, the compound having formula (a) is a compound having formula (a1).

[0064] (a1).

[0065] In another form, hindered oligomeric amines include compounds having the following formula (b).

[0066] (b)

[0067] Where b1 is a number from 1 to 10.

[0068] In particularly preferred forms, the hindered oligomeric amines include compounds having formula (a), preferably compounds having formula (a1).

[0069] Hindered oligomers can include a mixture of at least two different hindered oligomers.

[0070] Preferably, the hindered oligomeric amine comprises a mixture of two different hindered oligomeric amines, wherein one of the hindered oligomeric amines in the mixture comprises a compound having formula (a), preferably a compound having formula (a1).

[0071] In another preferred embodiment, the hindered oligomeric amine comprises a mixture of two different hindered oligomeric amines, wherein one of the hindered oligomeric amines in the mixture comprises a compound having formula (a), and

[0072] The hindered oligomeric amine having formula (a) and another hindered oligomeric amine exist in weight ratios of 30:1 to 1:2, 20:1 to 1:1, 15:1 to 2:1, or 12:1 to 4:1.

[0073] In another preferred embodiment, the hindered oligomeric amine comprises a mixture of two different hindered oligomeric amines, wherein one of the hindered oligomeric amines in the mixture comprises a compound having formula (a1), and

[0074] The hindered oligomeric amine having formula (a1) and another hindered oligomeric amine exist in weight ratios of 30:1 to 1:2, 20:1 to 1:1, 15:1 to 2:1, or 12:1 to 4:1.

[0075] In particular, the hindered oligomeric amines include a mixture of two different hindered oligomeric amines, wherein one of the hindered oligomeric amines has formula (a) and the other has formula (b).

[0076] In particular, the hindered oligomeric amines include a mixture of two different hindered oligomeric amines, wherein one of the hindered oligomeric amines has formula (a1) and the other has formula (b).

[0077] Specifically, the hindered oligomeric amine comprises a mixture of two different hindered oligomeric amines, wherein one of the hindered oligomeric amines has formula (a) and the other has formula (b), and

[0078] The hindered oligomeric amine having formula (a) and another hindered oligomeric amine having formula (b) are present in weight ratios of 30:1 to 1:2, 20:1 to 1:1, 15:1 to 2:1, or 12:1 to 4:1.

[0079] Specifically, the hindered oligomeric amine comprises a mixture of two different hindered oligomeric amines, wherein one of the hindered oligomeric amines has formula (a1) and the other has formula (b), and

[0080] The hindered oligomeric amine having formula (a1) and another hindered oligomeric amine having formula (b) are present in weight ratios of 30:1 to 1:2, 20:1 to 1:1, 15:1 to 2:1, or 12:1 to 4:1.

[0081] Specifically, the hindered oligomeric amine comprises a mixture of two different hindered oligomeric amines, wherein one of the hindered oligomeric amines has formula (a) and the other has formula (b), and

[0082] The hindered oligomeric amine having formula (a) and another hindered oligomeric amine having formula (b) are present in a weight ratio of 20:1 to 1:1, preferably 15:1 to 2:1, and particularly 12:1 to 4:1.

[0083] Specifically, the hindered oligomeric amine comprises a mixture of two different hindered oligomeric amines, wherein one of the hindered oligomeric amines has formula (a1) and the other has formula (b), and

[0084] The hindered oligomeric amine having formula (a1) and another hindered oligomeric amine having formula (b) are present in a weight ratio of 20:1 to 1:1, preferably 15:1 to 2:1, and particularly 12:1 to 4:1.

[0085] Preferably, the melt does not contain fluorine-based polymers, such as perfluoroalkyl and polyfluoroalkyl substances (also known as PFAS). Examples of fluorine-based polymers are fluoropolymers (i.e., fluorinated elastomers or amorphous fluorinated polymers) and thermoplastic fluorinated polymers (i.e., semi-crystalline fluorinated polymers). Fluorinated elastomers are fluorinated polymers that are normally in a fluid state at room temperature and above, i.e., fluorinated polymers with a Tg value below room temperature and exhibiting very little or no crystallinity at room temperature. Fluorinated monomers that can be copolymerized to produce suitable fluorinated elastomers include vinylidene fluoride, hexafluoropropylene, trifluorochloroethylene, tetrafluoroethylene, and perfluoroalkyl perfluorovinyl ethers. Specific examples of fluorinated elastomers include copolymers of vinylidene fluoride with comonomers selected from hexafluoropropylene, trifluorochloroethylene, 1-hydropentafluoropropylene, and 2-hydropentafluoropropylene; copolymers of vinylidene fluoride, tetrafluoroethylene, and hexafluoropropylene or 1- or 2-hydropentafluoropropylene; and copolymers of tetrafluoroethylene, propylene, and optionally vinylidene fluoride. Suitable semi-crystalline fluoropolymers are homopolymers and copolymers of poly(vinylidene fluoride) and tetrafluoroethylene (such as Teflon FEP fluorocarbon resin, and copolymers of tetrafluoroethylene, propylene and optional vinylidene fluoride).

[0086] Examples of suitable thermoplastic polymers are:

[0087] 1. Polymers of monoolefins and dienes, such as polypropylene, polyisobutylene, polybut-1-ene, poly-4-methylpent-1-ene, polyvinylcyclohexane, polyisoprene or polybutadiene, and polymers of cycloolefins, such as polymers of cyclopentene or norbornene, polyethylene (which may optionally be crosslinked), such as high-density polyethylene (HDPE), high-density and high-molecular-weight polyethylene (HDPE-HMW), high-density and ultra-high-molecular-weight polyethylene (HDPE-UHMW), medium-density polyethylene (MDPE), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), (VLDPE) and (ULDPE).

[0088] Polyolefins, namely polymers of the monoolefins exemplified in the previous paragraph, preferably polyethylene and polypropylene, can be prepared by various methods and, in particular, by the following methods:

[0089] a) Free radical polymerization (typically under high pressure and at elevated temperatures).

[0090] b) Catalytic polymerization using catalysts typically containing one or more metals from Group IVb, Vb, VIb, or VIII of the periodic table. These metals typically have one or more ligands, typically oxides, halides, alkoxides, esters, ethers, amines, alkyl, alkenyl, and / or aryl groups, which may be □-coordinated or □-coordinated. These metal complexes may be in free form or immobilized on a substrate, typically on activated magnesium chloride, titanium(III) chloride, alumina, or silica. These catalysts may be soluble or insoluble in the polymerization medium. The catalyst itself may be used in the polymerization, or additional activators may be used, typically metal alkyl groups, metal hydrides, metal alkyl halides, metal alkyl oxides, or metal alkyloxanes, where the metal is an element from Group Ia, IIa, and / or IIIa of the periodic table. The activator may be conveniently modified with additional ester, ether, amine, or silyl ether groups. These catalyst systems are commonly referred to as Phillips, Standard Oil Indiana, Ziegler (Natta), TNZ (DuPont), metallocene, or single-point catalyst (SSC).

[0091] 2. Mixtures of polymers mentioned in 1), such as mixtures of polypropylene and polyisobutylene, mixtures of polypropylene and polyethylene (e.g., PP / HDPE, PP / LDPE), and mixtures of different types of polyethylene (e.g., LDPE / HDPE).

[0092] 3. Copolymers of monoolefins and dienes with each other or with other vinyl monomers, such as ethylene / propylene copolymers, linear low-density polyethylene (LLDPE) and mixtures thereof with low-density polyethylene (LDPE), propylene / but-1-ene copolymers, propylene / isobutene copolymers, ethylene / but-1-ene copolymers, ethylene / hexene copolymers, ethylene / methylpentene copolymers, ethylene / heptene copolymers, ethylene / octene copolymers, ethylene / vinylcyclohexane copolymers, ethylene / cycloolefin copolymers (e.g., ethylene / norbornene like COC), ethylene / 1-olefin copolymers (where the 1-olefin is generated in situ); propylene / butadiene copolymers, isobutene / isoprene copolymers, ethylene / vinylcyclohexene copolymers, ethylene / alkyl acrylate copolymers, ethylene / alkyl methacrylate copolymers, ethylene / vinyl acetate copolymers or ethylene / acrylic acid copolymers and their salts (ionomers), and terpolymers of ethylene with propylene and dienes (such as hexadiene, dicyclopentadiene or ethylene-norbornene); and such copolymers with each other and with the above in 1). Mixtures of polymers mentioned herein, such as polypropylene / ethylene-propylene copolymers, LDPE / ethylene-vinyl acetate copolymers (EVA), LDPE / ethylene-acrylic acid copolymers (EAA), LLDPE / EVA, LLDPE / EAA, and alternating or random polyalkylene / carbon monoxide copolymers and mixtures thereof with other polymers (e.g., polyamides).

[0093] 4. Hydrocarbon resins (e.g., C5-C9), including their hydrogenated modifiers (e.g., tackifiers) and mixtures of polyalkylene compounds and starch.

[0094] Homopolymers and copolymers from 1.) - 4.) can have any stereostructure, including syndiotactic, isotactic, semi-isotactic or atactic; atactic polymers are preferred. Stereoblock polymers are also included.

[0095] 5. Polystyrene, poly(p-methylstyrene), poly(□-methylstyrene).

[0096] 6. Aromatic homopolymers and copolymers derived from vinyl aromatic monomers, including all isomers of styrene, □-methylstyrene, vinyltoluene (especially p-vinyltoluene), ethylstyrene, propylstyrene, vinylbiphenyl, vinylnaphthalene, and vinylanthracene, and mixtures thereof. Homopolymers and copolymers may have any stereostructure, including syndiotactic, isotactic, semi-isotactic, or atactic; atactic polymers are preferred. Stereoblock polymers are also included.

[0097] 6a. A copolymer comprising the above-mentioned vinyl aromatic monomers and a comonomer selected from: ethylene, propylene, diene, nitrile, acid, maleic anhydride, maleimide, vinyl acetate and vinyl chloride or acrylic acid derivatives and mixtures thereof, such as styrene / butadiene, styrene / acrylonitrile, styrene / ethylene (interpolymer), styrene / alkyl methacrylate, styrene / butadiene / alkyl acrylate, styrene / butadiene / alkyl methacrylate, styrene / maleic anhydride, styrene / acrylonitrile / methyl acrylate; a high-impact-strength mixture of a styrene copolymer and another polymer (e.g., a polyacrylate, a diene polymer or an ethylene / propylene / diene terpolymer); and block copolymers of styrene, such as styrene / butadiene / styrene, styrene / isoprene / styrene, styrene / ethylene / butene / styrene or styrene / ethylene / propylene / styrene.

[0098] 6b. Derived from 6.) Hydrogenated aromatic polymers of the polymers mentioned below, particularly including polycyclohexylethylene (PCHE) prepared by hydrogenation of atactic polystyrene, commonly referred to as polyvinylcyclohexane (PVCH).

[0099] 6c. Hydrogenated aromatic polymers of the polymers mentioned below (derived from 6a.).

[0100] Homopolymers and copolymers can have any stereostructure, including syndiotactic, isotactic, semi-isotactic, or atactic; atactic polymers are preferred. Stereoblock polymers are also included.

[0101] 7. Graft copolymers of vinyl aromatic monomers such as styrene or □-methylstyrene, for example, styrene on polybutadiene, styrene on polybutadiene-styrene or polybutadiene-acrylonitrile copolymers; styrene and acrylonitrile (or methacrylonitrile) on polybutadiene; styrene, acrylonitrile and methyl methacrylate on polybutadiene; styrene and maleic anhydride on polybutadiene; styrene, acrylonitrile and maleic anhydride or maleimide on polybutadiene; styrene and maleimide on polybutadiene; styrene and alkyl acrylate or alkyl methacrylate on polybutadiene; styrene and acrylonitrile on ethylene / propylene / diene terpolymers; styrene and acrylonitrile on alkyl polyacrylate or alkyl polymethacrylate, styrene and acrylonitrile on acrylate / butadiene copolymers, and mixtures thereof with copolymers listed in 6) below, such as copolymer mixtures of polymers called ABS, MBS, ASA or AES.

[0102] 8. Chlorinated polymers, such as polychloroprene, chlorinated rubber, chlorinated copolymers of isobutylene and isoprene (halogenated butyl rubber), chlorinated or sulfonated polyethylene, copolymers of ethylene and vinyl chloride, homopolymers and copolymers of epichlorohydrin, especially polymers containing chlorinated vinyl compounds, such as polyvinyl chloride, polyvinylidene chloride and its copolymers, such as vinyl chloride / vinylidene chloride, vinyl chloride / vinyl acetate or vinylidene chloride / vinyl acetate copolymers.

[0103] 9. Polymers derived from □,□-unsaturated acids and their derivatives, such as polyacrylates and polymethyl methacrylates; polymethyl methacrylate, polyacrylamide and polyacrylonitrile modified with butyl acrylate impact.

[0104] 10. Copolymers of monomers mentioned in 9) with each other or with other unsaturated monomers, such as acrylonitrile / butadiene copolymer, acrylonitrile / alkyl acrylate copolymer, acrylonitrile / alkoxyalkyl acrylate, acrylonitrile / haloethylene copolymer, or acrylonitrile / alkyl methacrylate / butadiene terpolymer.

[0105] 11. Polymers derived from unsaturated alcohols and amines or their acyl derivatives or acetals, such as polyvinyl alcohol, polyvinyl acetate, polyvinyl stearate, polyvinyl benzoate, polyvinyl maleate, polyvinyl butyral, polyallyl phthalate or polyallyl melamine; and copolymers thereof with the olefins mentioned above in 1).

[0106] 12. Homopolymers and copolymers of cyclic ethers, such as polyalkylene glycols, polyethylene oxide, polypropylene oxide, or copolymers thereof with diglycidyl ether.

[0107] 13. Polyacetals, such as polyoxymethylene and those polyoxymethylenes containing ethylene oxide as a comonomer; polyacetals modified with thermoplastic polyurethane, acrylate or MBS.

[0108] 14. Polyphenylene ether and polyphenylene sulfide, and mixtures of polyphenylene ether with styrene polymers or polyamides.

[0109] 15. Polyurethanes derived on the one hand from hydroxyl-terminated polyethers, polyesters or polybutadiene and on the other hand from aliphatic or aromatic polyisocyanates, and their precursors.

[0110] 16. Polyamides and copolyamides derived from diamines and dicarboxylic acids and / or derived from aminocarboxylic acids or corresponding lactams, such as polyamide 4, polyamide 6, polyamide 6 / 6, 6 / 10, 6 / 9, 6 / 12, 4 / 6, 12 / 12, polyamide 11, polyamide 12, aromatic polyamides originating from m-xylenediamine and adipic acid; polyamides prepared from hexamethylenediamine and isophthalic acid and / or terephthalic acid with or without an elastomer as a modifier. Amines, such as poly-2,4,4-trimethylhexamethylene terephthalamide or polyisophthalamide; and block copolymers of the above-mentioned polyamides with polyolefins, olefin copolymers, ionomers or chemically bonded or grafted elastomers; or block copolymers with polyethers, such as with polyethylene glycol, polypropylene glycol or polybutane glycol; and polyamides or copolyamides modified with EPDM or ABS; and polyamides condensed during processing (RIM polyamide system).

[0111] 17. Polyurea, polyimide, polyamide-imide, polyetherimide, polyesterimide, polyvinylurea, and polybenzimidazole.

[0112] 18. Polyesters derived from dicarboxylic acids and diols and / or derived from hydroxycarboxylic acids or corresponding lactones, such as polyethylene terephthalate, polybutylene terephthalate, poly-1,4-dimethylolcyclohexane terephthalate, polyalkylene naphthalate (PAN) and polyhydroxybenzoate, as well as block coether esters derived from hydroxyl-terminated polyethers; and polyesters modified with polycarbonate or MBS.

[0113] 19. Polycarbonate and polyester carbonate.

[0114] 20. Polyketone.

[0115] 21. Polysulfone, polyethersulfone and polyetherketone.

[0116] 22. Blends of the above polymers (polymer blends), such as PP / EPDM, polyamide / EPDM or ABS, PVC / EVA, PVC / ABS, PVC / MBS, PC / ABS, PBTP / ABS, PC / ASA, PC / PBT, PVC / CPE, PVC / acrylate, POM / thermoplastic PUR, PC / thermoplastic PUR, POM / acrylate, POM / MBS, PPO / HIPS, PPO / PA 6.6 and copolymers, PA / HDPE, PA / PP, PA / PPO, PBT / PC / ABS or PBT / PET / PC.

[0117] Thermoplastic polymers can be virgin or recycled polymers, which can be obtained from domestic, commercial and industrial waste or from useful material collections. Recycled polymers can originate from separation and sorting, or from specific industrial sectors and return obligations, such as from the automotive, electrical / electronic, construction, agricultural and textile industries, or from households and businesses (e.g., supermarkets).

[0118] For example, thermoplastic polymers are polypropylene, polyethylene, any polypropylene copolymer or any polyethylene copolymer or any blend thereof.

[0119] Preferably, the thermoplastic polymer is linear low-density polyethylene (LLDPE).

[0120] The hindered oligomeric amine can be added directly to the extruder along with the thermoplastic polymer, or it can be premixed with the thermoplastic polymer and then added to the extruder.

[0121] Optionally, an interface agent can be incorporated into the composition. The role of the interface agent can be to shorten the onset or induction time until the polymer processing aid (PPA) effect is observable, or to further reduce the melt viscosity or energy consumption required to compound the polymer or enhance processability. Interface agents are typically relatively low molecular weight components, and for a specific system of PPA and thermoplastic polymers, they are preferably located at the interface between the two polymers. Interface agents can be introduced into the polymer at any point up to and including the final melt molding process. Ideally, the interface agent should be incorporated into the masterbatch step, where both components are present at high concentrations (i.e., at a concentration greater than or equal to 0.5 wt.% based on the total weight of the masterbatch).

[0122] Possible interface agents, particularly thermoplastic polymers, are characterized by: 1) being liquid (or molten) at extrusion temperatures; 2) having a lower melt viscosity than both melt-processable polymers and comb-like or comb-like block copolymer processing aids; and 3) being able to freely wet the surface of comb-like or comb-like block copolymer particles in extrudable compositions. Examples of such interface agents include, but are not limited to: i) silicone-polyether copolymers; ii) aliphatic polyesters, such as poly(butylene adipate), poly(lactic acid), and polycaprolactone polyesters; iii) aromatic polyesters, such as diisobutyl phthalate; iv) polyether polyols (preferably not polyepoxides), such as poly(tetramethylene ether glycol); v) amine oxides, such as octyl dimethylamine oxide; vi) carboxylic acids, such as hydroxysuccinic acid; vii) fatty acid esters, such as sorbitan monolaurate and triglycerides; and vii) poly(olefin oxide) polymers, including polyethylene glycol and its derivatives. Preferred aliphatic interface agents are polyethylene glycol or aliphatic polyesters (preferably polycaprolactone) having a number average molecular weight in the range of 500 to 32,000, preferably 1,000 to 15,000, and most preferably 2,000 to 12,000.

[0123] Thermoplastic polymers may contain additional additives such as antioxidants, UV absorbers, light stabilizers, metal deactivators, peroxide scavengers, nucleating agents, fillers, reinforcing agents, and distributing agents, preferably inorganic distributing agents such as calcium carbonate, silicon oxide, talc, or any combination thereof.

[0124] For ease of processing, hindered oligomeric amines are typically used as masterbatches rather than pure forms when added to polymers. Within the scope of this invention, the masterbatch is typically a mixture of hindered oligomeric amines in a carrier polymer. The carrier polymer can be the same polymer to be extruded, or it can be a second polymer that does not adversely affect the extrusion behavior of the thermoplastic polymer to be extruded.

[0125] The masterbatch typically contains 0.5-50 wt.%, preferably 1-30 wt.%, of hindered oligomers based on the total weight of the masterbatch. The masterbatch can be prepared, for example, by mixing an appropriate amount of the hindered oligomer with a carrier polymer in a mixer (e.g., a Banbury mixer) or a co-rotating twin-screw extruder at a temperature above the polymer's melting point.

[0126] Typically, such masterbatches contain a) a carrier polymer, b) 0.5 to 50% by weight of hindered oligomeric amines and optional c) an effective amount of interfacial agents.

[0127] Preferably, the melt is processed by extrusion, such as film extrusion (cast film; blown film), fiber extrusion, pipe extrusion, profile extrusion, sheet extrusion or strip extrusion.

[0128] The present invention also relates to a method for improving the flow properties of a melt comprising a thermoplastic polymer, the method comprising the step of incorporating an oligomeric hindered amine into the thermoplastic polymer before or during melt processing (preferably extrusion).

[0129] The thermoplastic polymers contained in these polymers do not contain polymer processing aids, and preferably do not contain fluorine-based polymers.

[0130] Melt processing is preferably extrusion, such as film extrusion (cast film; blown film), fiber extrusion, pipe extrusion, profile extrusion, sheet extrusion or strip extrusion. Example

[0131] Polyethylene A: Commercial high molecular weight linear low density polyethylene ExxonMobil LL 1201 XV from ExxonMobil.

[0132] Polyethylene B: Commercial high molecular weight linear low density polyethylene ExxonMobil LD251 from ExxonMobil.

[0133] Fluoro-PPA: Dynamar® FX 5920A (a commercially available polymer processing aid from 3M), which contains a fluorinated elastomer of vinylidene fluoride-hexafluoropropylene (25-35 wt%), an interfacial agent such as PEG (60-70 wt%), and small amounts of distributing agents such as talc and calcium carbonate (both at concentrations < 5 wt%).

[0134] HALS-1: A high molecular weight hindered amine light stabilizer with formula (a1) (molecular weight approximately 1700 g / mol).

[0135] HALS-2: A commercially available high molecular weight hindered amine light stabilizer from BASF SE, with a molecular weight of 2600-3400 g / mol, and has the following formula:

[0136]

[0137] Where b1 is a number from 1 to 10.

[0138] Example 1: Preparation of Masterbatch

[0139] Polyethylene A or B and processing aids fluoro-PPA, HALS-1, HALS-2, HALS-3 or HALS-4 are blended in the amounts indicated in Table 1, and then melt-blended into pellets on a 25 mm co-rotating twin-screw extruder (Berstorff ZE25A x 47D) operating at a set temperature of 160 rpm and 190°C, and then extruded into pellets.

[0140] Table 1: Composition of Masterbatch

[0141]

[0142] a) Comparison

[0143] Example 2: Performance as a processing aid

[0144] The granulated masterbatch from Example 1 and polyethylene A were dry-blended in the amounts indicated in Table 2 and melt-processed into monofilaments through a 1.5 mm die on a 20 mm single-screw extruder Extrusionmeter 20D at a set temperature of 220°C.

[0145] For each masterbatch tested, the time until melt fracture or sharkskin was eliminated from the extruded monofilament is recorded in Table 2.

[0146] Between each formulation, the extruder was purged with polyethylene A until the original pressure observed in the case of pure polymer was restored, and subsequent formulations were tested only after this.

[0147] Masterbatches MB-B, MB-C, and MB-D significantly improved the processing properties of thermoplastic polymers.

[0148] exist Figure 1 The image shows photographs of monofilament sample 1 (comparison) after 5 min (A) and 60 min (B). It shows that even after 60 min, the sharkskin was not eliminated.

[0149] exist Figure 2 The image shows photographs of monofilament sample 3 after 5 minutes (A) and 30 minutes (B). It shows that after 30 minutes, the sharkskin is no longer visible.

[0150] exist Figure 3 The image shows photographs of monofilament sample 6 after 5 minutes (A) and 15 minutes (B). It shows that after 15 minutes, the sharkskin is no longer visible.

[0151] Table 2

[0152]

[0153] a) Comparison.

Claims

1. Use of hindered oligomeric amines to improve the flow properties of melts containing thermoplastic polymers.

2. The use according to claim 1, wherein, The melt contains 0.01 to 4 wt%, preferably 0.05 to 2 wt%, more preferably 0.1 to 1.5 wt%, and particularly 0.2 to 1.0 wt% of the hindered oligomeric amine.

3. The use according to claim 1 or 2, wherein, The hindered oligomeric amine has a molecular weight of at least 1000 g / mol, preferably at least 1300 g / mol, and particularly at least 1500 g / mol.

4. The use according to any one of claims 1 to 3, wherein, The thermoplastic polymer is polypropylene, polyethylene, any polypropylene copolymer or any polyethylene copolymer or any blend thereof.

5. The use according to any one of claims 1 to 4, wherein, The thermoplastic polymer is linear low-density polyethylene.

6. The use according to any one of claims 1 to 5, wherein, The melt is processed by extrusion.

7. The use according to any one of claims 1 to 6, wherein, This melt does not contain fluorine-based polymers.

8. The use according to any one of claims 1 to 7, wherein, The improved flow characteristics result in reduced melt fracture.

9. The use according to any one of claims 1 to 8, wherein, The hindered oligomeric amine comprises a mixture of at least two different hindered oligomeric amines.

10. The use according to any one of claims 1 to 9, wherein, The hindered oligomeric amine includes compounds selected from the following: compounds having formula (I). (I) in b1 is a number from 1 to 20; Group R1 is independently hydrogen, C1-C8 alkyl, or O. . -OH, -CH2CN, C1-C 18 Alkoxy, C5-C 12 Cycloalkoxy, C3-C6 alkenyl, unsubstituted or C7-C9 phenylalkyl substituted with 1, 2 or 3 C1-C4 alkyl groups on the phenyl group; or C1-C8 acyl group; R2 is C2-C 18 Alkylene, C5-C7 cycloalkylene, or C1-C4 alkylene di(C5-C7 cycloalkylene); R3 and R4 are independently hydrogen, C1-C 12 Alkyl, unsubstituted, or C5-C substituted with 1, 2, or 3 C1-C4 alkyl groups 12 Cycloalkyl; unsubstituted phenyl or phenyl substituted with 1, 2 or 3 C1-C4 alkyl groups; unsubstituted C7-C9 phenylalkyl or phenyl substituted with 1, 2 or 3 C1-C4 alkyl groups; or groups having formula (Ia). (him) or R3 and R4 together with the nitrogen atoms they are attached to form 5- to 10-membered heterocycles; and / or compounds having formula (II) (II) in b2 is a number from 1 to 20; Group X1 is independently hydrogen, C1-C8 alkyl, or O. . -OH, -CH2CN, C1-C 18 Alkoxy, C5-C 12 Cycloalkoxy, C3-C6 alkenyl, unsubstituted or C7-C9 phenylalkyl substituted with 1, 2 or 3 C1-C4 alkyl groups on the phenyl group; or C1-C8 acyl group; Group Y1 is independently hydrogen, C1-C 12 Alkyl, unsubstituted, or C5-C substituted with 1, 2, or 3 C1-C4 alkyl groups 12 Cycloalkyl; unsubstituted or substituted phenyl groups with 1, 2 or 3 C1-C4 alkyl groups; unsubstituted or substituted C7-C9 phenylalkyl groups with 1, 2 or 3 C1-C4 alkyl groups; or groups having formula (IIa); (IIa) Group Z1 is independently C2-C. 18 Alkylene, C5-C7 cycloalkylene or C1-C4 alkylene di(C5-C7 cycloalkylene).

11. The use according to any one of claims 1 to 10, wherein, The hindered oligomeric amine includes Where b1 is a number from 1 to 10.

12. A method for improving the flow properties of a melt comprising a thermoplastic polymer, the method comprising the step of incorporating an oligomeric hindered amine into the thermoplastic polymer prior to or during melt processing, wherein the thermoplastic polymer is free of polymer processing aids, preferably free of fluorine-based polymers.

13. The method according to claim 12, wherein, The melt contains 0.01 to 4 wt%, preferably 0.05 to 2 wt%, more preferably 0.1 to 1.5 wt%, and particularly 0.2 to 1.0 wt% of the hindered oligomeric amine.

14. The method according to claim 12 or 13, wherein, The hindered oligomeric amine has a molecular weight of at least 1000 g / mol, preferably at least 1300 g / mol, and particularly at least 1500 g / mol.

15. The method according to any one of claims 12 to 14, wherein, The thermoplastic polymer is polypropylene, polyethylene, any polypropylene copolymer or any polyethylene copolymer or any blend thereof.

16. The method according to any one of claims 12 to 15, wherein, The improved flow characteristics result in reduced melt fracture.

17. The method according to any one of claims 12 to 16, wherein, The hindered oligomeric amine includes Where b1 is a number from 1 to 10.

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