Crosslinked Polymers of Ethylene and Monocyclic Organosiloxane and Process

Abstract

Disclosed is a process includes providing (A) an ethylene/MOCOS copolymer composed of (i) units derived from ethylene, (ii) from 0.01 wt % to 0.5 wt % units derived from a comonomer, and (iii) optionally units derived from a termonomer. The comonomer is a monocyclic organosiloxane (MOCOS) of formula (I) [R.sup.1, R.sup.2SiO.sub.2/2].sub.n wherein n is an integer greater than or equal to 3, each R.sup.1 is independently a (C.sub.2_C.sub.4) alkenyl or a H.sub.2C═C (R.sup.1a)—C(═O)—O—(CH.sub.2).sub.m_ wherein R.sup.1a is H or methyl; m is an integer from 1 to 4; and each R.sup.2 is independently H, (C.sub.1_C.sub.4) alkyl, phenyl, or R.sup.1. The process includes mixing (B) a free radical initiator with (A) the ethylene/MOCOS copolymer to form a mixture, heating the mixture, and forming a crosslinkable ethylene/MOCOS copolymer composition having a gel content greater than 70%.

Claims

1. A process comprising: providing (A) an ethylene/MOCOS copolymer comprising (i) units derived from ethylene, (ii) from 0.01 wt % to 0.5 wt % units derived from a comonomer, and (iii) optionally units derived from a termonomer, and the comonomer is a monocyclic organosiloxane (MOCOS) of formula (I)
[R.sup.1,R.sup.2SiO.sub.2/2].sub.n wherein n is an integer greater than or equal to 3, each R.sup.1 is independently a (C.sub.2-C.sub.4)alkenyl or a H.sub.2C═C(R.sup.1a)—C(═O)—O—(CH.sub.2).sub.m— wherein R.sup.1a is H or methyl; m is an integer from 1 to 4; and each R.sup.2 is independently H, (C.sub.1-C.sub.4)alkyl, phenyl, or R.sup.1; mixing (B) a free radical initiator with (A) the ethylene/MOCOS copolymer to form a mixture; heating the mixture; and forming a crosslinkable ethylene/MOCOS copolymer composition.

2. The process of claim 1 comprising crosslinking the crosslinkable ethylene/MOCOS copolymer composition; and forming a crosslinked ethylene/MOCOS copolymer composition having a gel content greater than 70%.

3. The process of claim 1 comprising providing an ethylene/MOCOS copolymer wherein the MOCOS comonomer is selected from the group consisting of 2,4,6-trimethyl-2,4,6-trivinyl-cyclotrisiloxane, 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane, 2,4,6,8,10-pentamethyl-2,4,6,8,10-pentavinyl-cyclopentasiloxane, and combinations thereof.

4. The process of claim 1 comprising mixing from 3 wt % to 0.3 wt % of the free radical initiator (B) with from 97 wt % to 99.7 wt % of the ethylene/MOCOS copolymer (A); heating the mixture at a temperature from 70° C. to 90° C.; curing the crosslinkable ethylene/MOCOS copolymer composition; and forming a crosslinked ethylene/MOCOS copolymer composition having a T90 less than 5 minutes.

5. The process of claim 1 comprising mixing from 1.5 wt % to 0.5 wt % of the free radical initiator (B) with from 98.5 wt % to 99.5 wt % of an ethylene/MOCOS copolymer (A) having from 0.3 wt % to 0.5 wt % units derived from the MOCOS comonomer; heating the mixture at a temperature from 70° C. to 90° C.; forming a crosslinkable ethylene/MOCOS copolymer composition; curing the crosslinkable ethylene/MOCOS copolymer composition; and forming a crosslinked ethylene/MOCOs copolymer composition having a hot creep elongation from 20% to 50%.

6. The process of claim 1 comprising mixing from 1.5 wt % to 0.5 wt % of the free radical initiator (B) with from 98.5 wt % to 99.5 wt % of an ethylene/MOCOS copolymer (A) having from 0.05 wt % to 0.2 wt % units derived from the MOCOS comonomer; heating the mixture at a temperature from 70° C. to 90° C.; and forming a crosslinkable ethylene/MOCOS copolymer composition; curing the crosslinkable ethylene/MOCOS copolymer composition; and forming a crosslinked ethylene/MOCOs copolymer composition having a hot creep elongation from 50% to 90%.

7. A crosslinkable ethylene-based polymer composition comprising: (A) an ethylene copolymer comprising (i) units derived from ethylene, (ii) from 0.01 wt % to 0.5 wt % units derived from a comonomer, (iii) optionally units derived from a termonomer; and the comonomer is a monocyclic organosiloxane (MOCOS) of formula (I)
[R.sup.1,R.sup.2SiO.sub.2/2].sub.n wherein n is an integer greater than or equal to 3, each R.sup.1 is independently a (C.sub.2-C.sub.4)alkenyl or a H.sub.2C═C(R.sup.1a)—C(═O)—O—(CH.sub.2).sub.m— wherein R.sup.1a is H or methyl; m is an integer from 1 to 4; and each R.sup.2 is independently H, (C.sub.1-C.sub.4)alkyl, phenyl, or R.sup.1; (B) a free radical initiator; and the ethylene/MOCOS copolymer composition, after crosslinking, has a gel content greater than 70%.

8. The crosslinkable ethylene-based polymer composition of claim 7 wherein the MOCOS comonomer is selected from the group consisting of 2,4,6-trimethyl-2,4,6-trivinyl-cyclotrisiloxane, 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane, 2,4,6,8,10-pentamethyl-2,4,6,8,10-pentavinyl-cyclopentasiloxane, and combinations thereof.

9. The crosslinkable ethylene-based polymer composition of claim 7 comprising (A) from 97 wt % to 99.95 wt % of the ethylene/MOCOS copolymer; and (B) from 3 wt % to 0.05 wt % of the free radical initiator.

10. The crosslinkable ethylene-based polymer composition of claim 7 comprising from 98.5 wt % to 99.5 wt % of an ethylene/MOCOS copolymer (A) having from 0.3 wt % to 0.5 wt % units derived from the MOCOS comonomer; from 1.5 wt % to 0.5 wt % of the free radical initiator (B); and the ethylene/MOCOS copolymer composition, after crosslinking, has a hot creep elongation from 20% to 50%.

11. The crosslinkable ethylene-based polymer composition of claim 7 comprising from 98.5 wt % to 99.5 wt % of an ethylene/MOCOS copolymer (A) having from 0.05 wt % to 0.2 wt % units derived from the MOCOS comonomer; from 1.5 wt % to 0.5 wt % of the free radical initiator (B); the ethylene/MOCOS copolymer composition, after crosslinking, has a hot creep elongation from 50% to 90%.

12. The crosslinkable ethylene-based polymer composition of claim 7 wherein the MOCOS comonomer is 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane and the ethylene/MOCOS copolymer has (i) a Mw/Mn from 7.5 to 9.5, (ii) a vinyls content from 0.3600/1000 carbons to 0.6200/1000 carbons, and (iii) a trans content from 0.1000/1000 carbon atoms to 0.3100/1000 carbon atoms.

13. The crosslinkable ethylene-based polymer composition of claim 12 comprising an antioxidant.

14. A crosslinked ethylene-based polymer composition formed from the crosslinkable composition of claim 1.

15. An article comprising the crosslinked ethylene-based polymer composition of claim 14.

Description

DETAILED DESCRIPTION

1. Process

[0063] The present disclosure provides a process. In an embodiment, the process includes providing (A) an ethylene/MOCOS copolymer. The ethylene/MOCOS copolymer includes (i) units derived from ethylene, (ii) from 0.01 wt % to 0.5 wt % units derived from a comonomer, and (iii) optionally units derived from a termonomer. The comonomer is a monocyclic organosiloxane (MOCOS) of formula (I)

[R.sup.1,R.sup.2SiO.sub.2/2].sub.n [0064] wherein n is an integer greater than or equal to 3, [0065] each R.sup.1 is independently a (C.sub.2-C.sub.4)alkenyl or a H.sub.2C═C(R.sup.1a)—C(═O)—O—(CH.sub.2).sub.m— [0066] wherein R.sup.1a is H or methyl; [0067] m is an integer from 1 to 4; and [0068] each R.sup.2 is independently H, (C.sub.1-C.sub.4)alkyl, phenyl, or R.sup.1.
The process includes mixing (B) a free radical initiator with (A) the ethylene/MOCOS copolymer to form a mixture. The process includes heating the mixture for a period of time, and forming a crosslinkable ethylene/MOCOS copolymer composition.

[0069] In an embodiment, the process includes heating the crosslinkable composition at a curing temperature for a period of time, and forming a crosslinked ethylene/MOCOS copolymer composition having a gel content greater than 70%.

[0070] The process includes providing an ethylene/MOCOS copolymer. The ethylene/MOCOS copolymer is an ethylene-based polymer and includes (i) units derived from ethylene, (ii) units derived from a comonomer, and (iii) optionally units derived from a termonomer. The comonomer is a monocyclic organosiloxane (MOCOS) of formula (I)

[R.sup.1,R.sup.2SiO.sub.2/2].sub.n [0071] wherein n is an integer greater than or equal to 3, [0072] each R.sup.1 is independently a (C.sub.2-C.sub.4)alkenyl or a H.sub.2C═C(R.sup.1a)—C(═O)—O—(CH.sub.2).sub.m- [0073] wherein R.sup.1a is H or methyl, [0074] m is an integer from 1 to 4, and [0075] each R.sup.2 is independently H, (C.sub.1-C.sub.4)alkyl, phenyl, or R.sup.1.

[0076] The ethylene-based polymer with monocyclic organosiloxane (MOCOS) of formula (I) is interchangeably referred to as “ethylene/MOCOS copolymer”, and when a termonomer is present the ethylene-based polymer with monocyclic organosiloxane (MOCOS) of formula (I) is interchangeably referred to as “ethylene/MOCOS/terpolymer,” wherein the units of ethylene constitute a majority amount (wt %) of the monomers present in the polymer. In other words, the ethylene-based polymer composition includes ethylene monomer, MOCOS comonomer (and optional termonomer) each of the two monomers (or each of the three monomers when the termonomer is present) polymerized into the polymer backbone. In this way, the present ethylene/MOCOS copolymer (and/or ethylene/MOCOS/termpolymer) is structurally distinct compared to a polyethylene with a functional coagent grafted pendant to the polymer chain. Weight percent of the MOCOS comonomer is based on the total weight of the ethylene/MOCOS copolymer (or total weight of the ethylene/MOCOS/terpolymer when the termonomer is present).

[0077] In addition to ethylene, the ethylene/MOCOS copolymer includes units derived from a comonomer. The comonomer is a monocyclic organosiloxane of formula (I) [R.sup.1, R.sup.2SiO.sub.2/2].sub.n (interchangeably referred to as “MOCOS” or “MOCOS comonomer”), formula (I) being a molecule containing a single ring substructure composed of silicon and oxygen atoms disposed in an alternating arrangement; and formula (I) containing unsaturated organo (hydrocarbonyl) groups; and optionally hydrogen (“H”), saturated substituent groups or aromatic substituent groups. At least two unsaturated organo groups and each of at least two silicon atoms in the ring substructure have at least one unsaturated organo group bonded thereto and wherein after accounting for the unsaturated organo groups and oxygen atoms, any remaining valences of the silicon atoms are bonded to the hydrogen atom, saturated substituent groups, or aromatic substituent groups; or collection of such molecules.

[0078] The MOCOS may be a monocyclic organosiloxane composed of a 6-member ring (n=3), an 8-member ring (n=4), a 10-member ring (n-5), or a 12-member ring (n=6). The ring substructure is composed of units of formula (I):

[R.sup.1,R.sup.2SiO.sub.2/2].sub.n, [0079] wherein n is an integer greater than or equal to 3, or n is 3, or 4 to 5, or 6, [0080] each R.sup.1 is independently a (C.sub.2-C.sub.4)alkenyl or a H.sub.2C═C(R.sup.1a)—C(═O—O—(CH.sub.2).sub.m-, wherein R.sup.1a is H or methyl, [0081] each R.sup.2 is independently H, (C.sub.1-C.sub.4)alkyl, phenyl, or R.sup.1 (as defined above). In each [R.sup.1,R.sup.2SiO.sub.2/2] unit, the R.sup.1 group and the R.sup.2 group is bonded to its respective silicon atom. The units may be designated using conventional organosiloxane shorthand notations simply as D.sup.R1,R2 such that formula (I) becomes [D.sup.R1,R2].sub.n. R.sup.1 and R.sup.2 can be the same or different.

[0082] Nonlimiting examples of suitable compounds for MOCOS of formula (I) include: R.sup.1 is vinyl and R.sup.2 is ethyl for MOCOS shorthand designation D.sup.Vi,Et wherein Vi is vinyl and Et is ethyl; R.sup.1 is allyl and R.sup.2 is ethyl for MOCOS shorthand designation D.sup.Allyl,Et; R.sup.1 is butenyl (H.sub.2C═C(H)CH.sub.2CH.sub.2—) and R.sup.2 is ethyl for MOCOS shorthand designation D.sup.Butenyl,Et; R.sup.1 is vinyl and R.sup.2 is vinyl for MOCOS shorthand designation D.sup.Vi,Vi; R.sup.1 is allyl and R.sup.2 is allyl for MOCOS shorthand designation D.sup.Allyl,Allyl; R.sup.1 is butenyl (H.sub.2C═C(H)CH.sub.2CH.sub.2—) and R.sup.2 is butenyl for MOCOS shorthand designation D.sup.Butenyl,Butenyl; R.sup.1 is vinyl and R.sup.2 is phenyl for MOCOS shorthand designation D.sup.Vi,Ph wherein Ph is phenyl; R.sup.1 is allyl and R.sup.2 is phenyl for MOCOS shorthand designation D.sup.Allyl,Ph; R.sup.1 is butenyl (H.sub.2C═C(H)CH.sub.2CH.sub.2—) and R.sup.2 is phenyl for MOCOS shorthand designation D.sup.Butenyl,Ph.

[0083] When R.sup.2 is methyl (CH.sub.3), the unit may be designated more simply as D.sup.R1 such that formula (I) becomes [D.sup.R1].sub.n. Further nonlimiting examples of suitable compounds for MOCOS of formula (I) include: R.sup.1 is vinyl and R.sup.2 is methyl for MOCOS shorthand designation D.sup.Vi; R.sup.1 is allyl and R.sup.2 is methyl for MOCOS shorthand designation D.sup.Allyl; R.sup.1 is butenyl (H.sub.2C═C(H)CH.sub.2CH.sub.2—) and R.sup.2 is methyl for MOCOS shorthand designation D.sup.Butenyl.

[0084] In an embodiment, MOCOS of formula (I) each R.sup.1 is independently H.sub.2C═C(R.sup.1a)—C(═O)—O—(CH.sub.2).sub.m— wherein R.sup.1a is H or methyl, and subscript m is an integer from 1, or 2 to 3 or to 4, and any range or individual value therein. In a further embodiment, each R.sup.2 is independently (C.sub.1-C.sub.2)alkyl or (C.sub.2-C.sub.3)alkenyl; or each R.sup.2 is independently (C.sub.1-C.sub.2)alkyl; or each R.sup.2 is independently methyl.

[0085] In an embodiment, MOCOS of formula (I) is 2,4,6-trimethyl-2,4,6-trivinyl-cyclotrisiloxane, “(D.sup.Vi).sub.3” (CAS No. 3901-77-7) having Structure (B) below:

##STR00002##

[0086] In an embodiment, MOCOS of formula (I) is 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane, “(D.sup.Vi).sub.4” (CAS No. 2554-06-5), having Structure (C) below:

##STR00003##

[0087] In an embodiment, MOCOS of formula (I) is 2,4,6,8,10-pentamethyl-2,4,6,8,10-pentavinyl-cyclopentasiloxane, (D.sup.Vi).sub.5.

[0088] The MOCOS comonomer of formula (I) is present in the ethylene-based polymer in an amount from 0.01 wt % to 2 wt %, or from 0.01 wt % to 0.5 wt %, or from 0.05 wt % to 0.45 wt %, or from 0.1 wt % to 0.40 wt %, or from 0.3 wt % to 0.5 wt %, or from 0.15 wt % to 0.30 wt %, or from 0.05 wt % to 0.15 wt %. Weight percent is based on total weight of the ethylene-based polymer composition, namely, the ethylene/MOCOS copolymer.

[0089] In addition to the ethylene and the MOCOS comonomer, the ethylene/MOCOS copolymer includes optional units derived from a termonomer and is an ethylene/MOCOS/terpolymer. When present, the termonomer is an olefin, an unsaturated ester, a functionalized alkene, silane, and combinations thereof. Nonlimiting examples of suitable termonomer (when the termonomer is present) include propylene, C.sub.4-C.sub.8 alpha-olefin, acrylate, (meth)acrylate, vinyl acetate, vinyltrimethoxysilane, and combinations thereof. When the termonomer is present in the ethylene-based polymer, the termonomer is present in an amount from 0.5 wt % to 50 wt %, or from 1 wt % to 40 wt %, or from 1 wt % to 30wt %, or from 1 wt % to 25wt %, or from 1 wt % to 20wt % , or from 1 wt % to 15wt %, or from 3 wt % to 12 wt %, or from 5 wt % to 10 wt %. Weight percent is based on the total weight of the ethylene/MOCOS/terpolymer. S

[0090] In an embodiment, the present ethylene-based polymer composition includes the ethylene/ MOCOS copolymer of formula (I) and also includes a termonomer of formula (II)

[R.sup.1,R.sup.2SiO.sub.2/2].sub.n  formula (II) [0091] wherein n is an integer greater than or equal to 3, [0092] each R.sup.1 is independently a methyl group, a (C.sub.2-C.sub.4)alkenyl or a H.sub.2C═C(R.sup.1a)—C(═O)—O—(CH.sub.2).sub.m— with the proviso at least two R.sup.1's are not a methyl group, [0093] wherein R.sup.1a is H or methyl, [0094] m is an integer from 1 to 4, and [0095] each R.sup.2 is independently H, (C.sub.1-C.sub.4)alkyl, phenyl, or R.sup.1.

[0096] In an embodiment, the ethylene/MOCOS copolymer (and/or the ethylene/MOCOS/terpolymer) may be a component in an ethylene-based polymer composition that includes one or more optional additives. When the additive is present, non-limiting examples of suitable additives include stabilizers, light stabilizers, UV absorbers, antioxidants, plasticizers, antistatic agents, voltage stabilizers, crosslinking coagents and scorch retardants, pigments, dyes, carbon black, nanoparticles, nucleating agents, fillers, slip agents, fire retardants, processing aids, smoke inhibitors, viscosity control agents and anti-blocking agents. The ethylene-based polymer composition may, for example, include less than 70 percent of the combined weight of one or more additives and fillers, based on the weight of the ethylene-based polymer composition.

[0097] In an embodiment, the ethylene-based polymer composition is compounded with one or more antioxidants. Nonlimiting examples of suitable antioxidants include bis(4-(1-methyl-1-phenylethyl)phenyl)amine (e.g., NAUGARD 445); 2,2-methylene-bis(4-methyl-6-t-butylphenol) (e.g., VANOX MBPC); 2,2′-thiobis(2-t-butyl-5-methylphenol (CAS No. 90-66-4), CAS No. 96-69-5, commercially LOWINOX TBM-6); 2,2′-thiobis(6-t-butyl-4-methylphenol (CAS No. 90-66-4, commercially LOWINOX TBP-6); tris[(4-tert-butyl-3-hydroxy-dimethylphenyl)methyl]-1,3,5-triazine-2,4,6-trione (e.g., CYANOX 1790); pentaerythritol tetrakis(3-(3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl)propionate (e.g., IRGANOX 1010, CAS Number 6683-19-8); 3,5-bis(1,1-dimethylethyl)-4-hydroxybenzenepropanoic acid 2,2′-thiodiethanediyl ester (e.g., IRGANOX 1035, CAS Number 41484-35-9); distearylthiodipropionate (“DSTDP”); dilaurylthiodipropionate (e.g., IRGANOX PS 800); stearyl 3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate (e.g., IRGANOX 1076); 2,4-bis(dodecylthiomethyl)-6-methylphenol (IRGANOX 1726); 4,6-bis(octylthiomethyl)-o-cresol (e.g. IRGANOX 1520); and 2′,3-bis[[3-[3,5-di-tert-butyl-4-hydroxyphenyl]propionyl]] propionohydrazide (IRGANOX 1024); 4,4-thiobis(2-t-butyl-5-methyiphenoi) (also known as 4,4′-thiobis(6-tert-butyl-m-cresol); 2,2′-thiobis(6-t-butyl-4- methylphenol; tris[(4-tert-butyl-3-hydroxy-2,6-dimethylphenyl)methyl]-1,3,5-triazine-2,4,6-trione; distearylthiodipropionate; and combinations thereof. The antioxidant is present from 0.01 wt % to 1.5 wt %, or from 0.05 wt % to 1.2 wt %, or from 0.07 wt % to 1.0 wt %, or from 0.1 wt % to 0.5wt %, based on the total weight of the ethylene-based composition. The ethylene-based polymer composition is treated with the antioxidant(s) before the heating step.

[0098] In an embodiment, the ethylene-based polymer composition is an ethylene/MOCOS copolymer consisting of (i) ethylene and (ii) from 0.05 wt % to 0.5 wt % MOCOS copolymer selected from (D.sup.Vi).sub.3, (D.sup.Vi).sub.4, and (D.sup.Vi).sub.5, the ethylene/MOCOS copolymer having a Mw/Mn from 5.0 to 9.5, or from 7.5 to 9.5, a vinyls content from 0.3600/1000 carbon atoms to 0.6200/1000 carbon atoms, a trans content from 0.1000/1000 carbon atoms to 0.3100/1000 carbon atoms, and a MI from 2.0 g/10 min to 5.0 g/10 min.

[0099] In an embodiment, the ethylene-based polymer composition is an ethylene/MOCOS copolymer consisting of (i) ethylene and (ii) from 0.05 wt % to 0.5 wt % (D.sup.Vi).sub.4, the ethylene/MOCOS copolymer composition having one, some, or all of the following properties: [0100] (i) a Mw/Mn from 5.0 to 9.5 or from 7.5 to 9.5; and/or [0101] (ii) a vinyls content from 0.3600/1000 carbon atoms to 0.6200/1000 carbon atoms; and/or [0102] (iii) a trans content from 0.1000/1000 carbon atoms to 0.3100/1000 carbon atoms; and/or [0103] (iv) a MI from 2.0 g/10 min to 5.0 g/10 min, or from 2.5 g/10 min to 4.7 g/10 min.

[0104] In an embodiment, the ethylene-based polymer composition is an ethylene/MOCOS copolymer consisting of (i) ethylene and (ii) from 0.1 wt % to 0.5 wt % MOCOS copolymer selected from (D.sup.Vi).sub.4, the ethylene/MOCOS copolymer having a Mw/Mn from 7.0 to 7.5, a vinyls content from 0.5800/1000 carbons to 0.6200/1000 carbons, a trans content from 0.2000/1000 carbon atoms to 0.2500/1000 carbon atoms, and a MI from 35.0 g/10 min to 42.0 g/10 min.

[0105] In an embodiment, the ethylene-based polymer composition is an ethylene/MOCOS/MA terpolymer consisting of (i) ethylene, (ii) from 0.01 wt % to 0.5 wt % MOCOS and (iii) from 1 wt % to 50 wt % MA, or from 8 wt % to 12 wt % MA. Weight percent based on total weight of the ethylene/MOCOS/MA terpolymer.

[0106] The process includes mixing (B) a free radical initiator with (A) the ethylene/MOCOS copolymer to form a mixture. In an embodiment, the free radical initiator is an organic peroxide. The organic peroxide is a molecule containing carbon atoms, hydrogen atoms, and two or more oxygen atoms, and having at least one —O-group, with the proviso that when there are more than one —O—O-groups, each —O—O-group is bonded indirectly to another —O—O-group via one or more carbon atoms, or collection of such molecules. Nonlimiting examples of suitable organic peroxide include diacylperoxides, peroxycarbonates, peroxydicarbonates, peroxyesters, peroxyketals, cyclic ketone peroxides, dialkylperoxides, ketone peroxides, and combinations thereof.

[0107] The organic peroxide may be a monoperoxide of formula R.sup.O—O—O—R.sup.O, wherein each R.sup.O independently is a (C.sub.1-C.sub.20) alkyl group or (C.sub.6-C.sub.20) aryl group. Each (C.sub.1-C.sub.20) alkyl group independently is unsubstituted or substituted with 1 or 2 (C.sub.6-C.sub.12) aryl groups. Each (C.sub.6-C.sub.20) aryl group is unsubstituted or substituted with 1 to 4 (C.sub.1-C.sub.10) alkyl groups. Alternatively, the organic peroxide may be a diperoxide of formula R.sup.O—O—O—R—O—O—R.sup.O, wherein R is a divalent hydrocarbon group such as a (C.sub.2-C.sub.10) alkylene, (C.sub.3-C.sub.10) cycloalkylene, or phenylene, and each R.sup.O is as defined above.

[0108] Nonlimiting examples of suitable organic peroxides include dicumyl peroxide; lauryl peroxide; benzoyl peroxide; tertiary butyl perbenzoate; di (tertiary-butyl) peroxide; cumene hydroperoxide; 2,5-dimethyl-2,5-di(t-butyl-peroxy)hexyne-3; 2,-5-di-methyl-2,5-di (t-butyl-peroxy) hexane; tertiary butyl hydroperoxide; isopropyl percarbonate; alpha, alpha′-bis (tertiary-butylperoxy) diisopropylbenzene; t-butylperoxy-2-ethylhexyl-monocarbonate; 1,1-bis (t-butylperoxy) -3,5,5-trimethyl cyclohexane; 2,5-dimethyl-2,5-dihydroxyperoxide; t-butylcumylperoxide; alpha, alpha′-bis (t-butylperoxy)-p-diisopropyl benzene; bis (1,1-dimethylethyl) peroxide; bis (1,1-dimethylpropyl) peroxide; 2,5-dimethyl-2, 5-bis (1,1-dimethylethylperoxy) hexane; 2,5-dimethyl-2,5-bis (1,1-dimethylethylperoxy) hexyne; 4,4-bis (1,1-dimethylethylperoxy) valeric acid; butyl ester; 1,1-bis (1,1-dimethylethylperoxy)-3,3,5-trimethylcyclohexane; benzoyl peroxide; tert-butyl peroxybenzoate; di-tert-amyl peroxide (“DTAP”); bis (alpha-t-butyl-peroxyisopropyl) benzene (“BIPB”); isopropylcumyl t-butyl peroxide; t-butylcumylperoxide; di-t-butyl peroxide; 2,5-bis (t-butylperoxy)-2,5-dimethylhexane; 2,5-bis (t-butylperoxy)-2,5-dimethylhexyne-3,1,1-bis (t-butylperoxy)-3,3,5-trimethylcyclohexane; isopropylcumyl cumylperoxide; butyl 4,4-di (tert butylperoxy) valerate; di (isopropylcumyl) peroxide; and the like.

[0109] Nonlimiting examples of suitable commercially available organic peroxides include TRIGONOX from AkzoNobel and LUPEROX from Arkema.

[0110] In an embodiment, the free radical initiator is an organic peroxide that is dicumyl peroxide (DCP).

[0111] Mixing of the ethylene/MOCOS copolymer (A) and the free radical initiator (B) occurs by placing pellets of the ethylene/MOCOS copolymer and the free radical initiator into a container and optionally with antioxidant(s). The container is subsequently shaken, rotated, tumbled, or otherwise agitated so that the free radical initiator contacts and is retained by, or otherwise the free radical initiator is absorbed into, the pellets of ethylene/MOCOS copolymer. The process includes heating the mixture of (A) the ethylene/MOCOS copolymer and (B) the free radical initiator at a temperature from 60° C., or 65° C. to 70° C., or 75° C., or 80° C., or otherwise heating at a temperature greater than the melting temperature of peroxide. Heating of the mixture occurs for a duration from 1 minute, or 10 minutes, or 30 minutes to 1 hour, or 2 hours, or 3 hours, or 4 hours, or 5 hours, or 6 hours, or 7 hours, or 8 hours, thereby enabling the free radical initiator to diffuse into the ethylene/MOCOS copolymer pellets.

[0112] In an embodiment, the mixing and the heating occur sequentially.

[0113] In an embodiment, the mixing and the heating occur simultaneously.

[0114] The process includes crosslinking (interchangeably referred to as “curing”) the crosslinkable ethylene/MOCOS copolymer composition, and forming a crosslinked ethylene/MOCOS copolymer composition having a gel content greater than 70%. In an embodiment, the crosslinked ethylene/MOCOS copolymer has a gel content from 71%, or 75%, or 80% to 85%, or 90%, or 95%, or 99%. In a further embodiment, the crosslinked ethylene/MOCOS copolymer has a gel content from 71% to 99%, or from 72% to 95%, or from 73 to 90%.

[0115] The curing step (crosslinking step) includes heating the crosslinkable ethylene/MOCOS copolymer composition at a curing temperature from greater than 100° C., or 110° C., or 125° C. to 150° C., or 180° C., or 200° C. for a duration from 1 minute, or 5 minutes, or 10 minutes, or 30 minutes, or 1 hour to 2 hours, or 5 hours, or 7 hours, or more to form the crosslinked ethylene/MOCOS copolymer composition having a gel content from 71% to 99%, or from 72% to 95%, or from 73 to 90%.

[0116] Crosslinking of the ethylene/MOCOS copolymer may be accomplished by a procedure that does not utilize peroxide initiator. In an embodiment, the process includes subjecting the ethylene/MOCOS copolymer to irradiation and forming a crosslinked ethylene/MOCOS copolymer having a gel content greater than 70%. The irradiation can be electron beam irradiation (E-beam), ultraviolet (UV) irradiation, photo initiation, and combinations thereof. In this embodiment, the mixing step and the heating step described are eliminated and replaced with the irradiation step. The crosslinked ethylene/MOCOS copolymer has a gel content a gel content greater than 70%, or from 71%, or 75%, or 80% to 85%, or 90%, or 95%, or 99%. In a further embodiment, the crosslinked ethylene/MOCOS copolymer has a gel content from 71% to 99%, or from 72% to 95%, or from 73 to 90%.

[0117] In an embodiment, the process includes mixing from 3 wt % to 0.05 wt % of the free radical initiator (B) with from 97 wt % to 99.95 wt % of the ethylene/MOCOS copolymer (A). The process includes heating the mixture at a temperature from 70° C. to 90° C. and forming a crosslinkable ethylene/MOCOS copolymer. The process includes curing the crosslinkable ethylene/MOCOS copolymer composition and forming a crosslinked ethylene/MOCOS copolymer composition having a T90 less than 5 minutes, or a T90 from 3.0 minutes to 4.9 minutes and a gel content from 71% to 99% after curing.

[0118] In an embodiment, the process includes mixing from 1.5 wt % to 0.5 wt % of the free radical initiator (B) with from 98.5 wt % to 99.5 wt % of an ethylene/MOCOS copolymer (A). The ethylene/MOCOS copolymer (A) has from 0.3 wt % to 0.5 wt % units derived from the MOCOS comonomer (based on total weight of the ethylene/MOCOS copolymer). The process includes heating the mixture at a temperature from 70° C. to 90° C. for 0.5 to 8 hr and forming a crosslinkable ethylene/MOCOS copolymer composition. The process includes curing the crosslinkable ethylene/MOCOS copolymer composition to form a crosslinked ethylene/MOCOS copolymer composition having a gel content from 71% to 99%, and a hot creep elongation from 20% to 50%

[0119] In an embodiment, the process includes mixing from 1.5 wt % to 0.5 wt % of the free radical initiator (B) with from 98.5 wt % to 99.5 wt % of an ethylene/MOCOS copolymer (A). The ethylene/MOCOS copolymer has from 0.05 wt % to 0.2 wt % units derived from the MOCOS comonomer (based on total weight of the ethylene/MOCOS copolymer). The process includes heating the mixture at a temperature from 70° C. to 90° C. for 2 to 6 hr, and forming a crosslinkeable ethylene/MOCOS copolymer composition. The process includes curing the crosslinkable ethylene/MOCOS copolymer composition to form a crosslinked ethylene/MOCOS copolymer composition having a gel content from 71% to 99% and having a hot creep elongation from 50% to 90%.

[0120] In an embodiment, the process includes mixing from 3 wt % to 0.3 wt % of the free radical initiator (B), with from 97 wt % to 99.7 wt % of the ethylene/MOCOS copolymer (A) and 0.05 wt % to 0.3 wt % one or more antioxidants (yielding 100 wt % of a crosslinkable ethylene-based polymer composition). The process includes heating the mixture at a temperature from 70° C. to 90° C. for 2 to 6 hr and forming a crosslinkable ethylene-based polymer composition. After curing, a crosslinked ethylene/MOCOS copolymer composition is formed having [0121] (1) a gel content from 64% to 99% and a T90 from 3.0 minutes to 5.3 minutes, or [0122] (2) a gel content from 71% to 99% and a T90 less than 5 minutes, or a T90 from 3.0 minutes to 4.9 minutes.

2. Composition

[0123] The present disclosure provides a composition that is a crosslinkable ethylene-based polymer composition. A “crosslinkable ethylene-based polymer composition,” as used herein, is a composition containing an ethylene-based polymer and one or more additives (a free radical initiator or organic peroxide, for example) that enhance the ethylene-based polymer's ability to crosslink when subjected to crosslinking conditions (e.g., heat, irradiation, and/or UV light). After being subjected to the crosslinking conditions (e.g., “after crosslinking” or “after curing”), the crosslinkable ethylene-based polymer composition becomes a “crosslinked ethylene-based polymer composition” that is structurally and physically distinct to the crosslinkable ethylene-based polymer composition.

[0124] In an embodiment, the crosslinked ethylene-based composition is formed by the peroxide initiation process as previously disclosed herein.

[0125] In an embodiment, a crosslinkable ethylene-based polymer composition is provided and includes (A) an ethylene copolymer composed of (i) units derived from ethylene, (ii) from 0.01 wt % to 0.5 wt % units derived from a comonomer, and (iii) optionally units derived from a termonomer. The comonomer is a monocyclic organosiloxane (MOCOS) of formula (I)

[R.sup.1,R.sup.2SiO.sub.2/2].sub.n [0126] wherein n is an integer greater than or equal to 3, [0127] each R.sup.1 is independently a (C.sub.2-C.sub.4)alkenyl or a H.sub.2C═(R.sup.1a)—C(═O)—O—(CH.sub.2).sub.m— [0128] wherein R.sup.1a is H or methyl; [0129] m is an integer from 1 to 4; and [0130] each R.sup.2 is independently H, (C.sub.1-C.sub.4)alkyl, phenyl, or R.sup.1 (ethylene/MOCOS copolymer). The crosslinkable ethylene-based polymer composition also includes (B) a free radical initiator. The crosslinkable ethylene/MOCOS copolymer composition, after crosslinking, forms a crosslinked ethylene/MOCOS copolymer having a gel content greater than 70%. In an embodiment, the crosslinked ethylene/MOCOS copolymer composition has a gel content from 71%, or 75%, or 80% to 85%, or 9%, or 95%, or 99%. In a further embodiment, the crosslinked ethylene/MOCOS copolymer composition has a gel content from 71% to 99%, or from 72% to 95%, or from 73 to 90%.

[0131] In an embodiment, the MOCOS comonomer for the ethylene/MOCOS copolymer is selected from 2,4,6-trimethyl-2,4,6-trivinyl-cyclotrisiloxane (D.sup.Vi).sub.3, 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane (D.sup.Vi).sub.4, 2,4,6,8,10-pentamethyl-2,4,6,8,10-pentaivinyl-cyclotrisiloxane (D.sup.Vi).sub.5, and combinations thereof.

[0132] In an embodiment, the MOCOS comonomer for the ethylene/MOCOS copolymer is (D.sup.Vi).sub.4. The crosslinked ethylene/MOCOS copolymer composition contains from 0.01 wt % to 0.5 wt % of (D.sup.Vi).sub.4 (based on total weight of the ethylene/MOCOS copolymer) and the crosslinked ethylene/MOCOS copolymer composition has one, some, or all of the following properties: [0133] (i) a Mw/Mn from 7.5 to 9.5, and/or [0134] (ii) a vinyls content from 0.3600/1000 carbons to 0.6200/1000 carbons, and/or [0135] (iii) a trans content from 0.1000/1000 carbon atoms to 0.3100/1000 carbon atoms.

[0136] In an embodiment, the crosslinkable ethylene-based polymer composition includes (A) from 97 wt % to 99.95 wt % of the ethylene/MOCOS copolymer; and (B) from 3 wt % to 0.05 wt % of the free radical initiator. Weight percent is based on total weight of the crosslinked ethylene/MOCOS copolymer composition.

[0137] In an embodiment, the crosslinkable ethylene-based polymer composition includes from 98.5 wt % to 99.5 wt % of an ethylene/MOCOS copolymer (A). The ethylene/MOCOS copolymer has from 0.3 wt % to 0.5 wt % units derived from the MOCOS comonomer (based on total weight of the ethylene/MOCOS copolymer). The crosslinkable ethylene-based polymer composition also includes from 1.5 wt % to 0.5 wt % of the free radical initiator (B). The crosslinkable ethylene/MOCOS copolymer composition, after crosslinking, forms a crosslinked ethylene/MOCOS copolymer composition having a gel content from 71% to 99%, or from 72% to 95%, or from 73% to 90%, and has a hot creep elongation from 20% to 50%.

[0138] In an embodiment, the crosslinkable ethylene-based polymer composition includes from 98.5 wt % to 99.5 wt % of an ethylene/MOCOS copolymer (A). The ethylene/MOCOS copolymer has from 0.05 wt % to 0.2 wt % units derived from the MOCOS comonomer (based on total weight of the ethylene/MOCOS copolymer). The crosslinkable ethylene-based polymer composition also includes from 1.5 wt % to 0.5 wt % of the free radical initiator (B). The crosslinkable ethylene/MOCOS copolymer composition, after crosslinking, forms a crosslinked ethylene/MOCOS copolymer composition having a gel content from 71% to 99%, or from 72% to 95%, or from 73% to 90% and has a hot creep elongation from 50% to 90%.

[0139] In an embodiment, the crosslinkable ethylene-based polymer composition includes from 98.5 wt % to 99.5 wt % of an ethylene/MOCOS copolymer (A). The ethylene/MOCOS copolymer has from 0.05 wt % to 0.2 wt % units derived from the MOCOS comonomer (based on total weight of the ethylene/MOCOS copolymer). The crosslinkable ethylene-based polymer composition also includes from 1.5 wt % to 0.5 wt % of the free radical initiator (B). The crosslinkable ethylene-based polymer composition includes from 0.05 wt % to 0.3 wt % of one or more antioxidants (yielding 100 wt % of the crosslinkable ethylene-based polymer composition). The crosslinkable ethylene-based polymer composition, after crosslinking, forms a crosslinked ethylene/MOCOS copolymer composition having one, some, or all of the following properties: [0140] (i) a gel content from 64% to 99% , or from 71% to 99%, or from 72% to 95%, or from 73% to 90%; and/or [0141] (ii) a T90 from 3.0 minutes to 5.3, or from 3.0 minutes to 4.9 minutes; and/or [0142] (iii) a hot creep elongation from 50% to 90%.

Applications

[0143] The crosslinked ethylene/MOCOS copolymer composition may be employed in a variety of applications including, but not limited to, wire and cable applications, such as an insulation layer for MV/HV/EHV cable for AC (alternating current) and DC (direct current), a semi-conductive layer filled with carbon black for MV/HV/EHV cable, an accessory for a power distribution transmission line, an insulation layer, an insulation encapsulation film for a photovoltaic (PV) module.

[0144] By way of example, and not limitation, some embodiments of the present disclosure will now be described in detail in the following examples.

EXAMPLES

[0145] Materials used in the examples are set forth in Table 1 below.

TABLE-US-00001 TABLE 1 Material Description Source LDPE control Ethylene homopolymer LDPE1 control 4 Ml Dow Inc. Ethylene homopolymer LDPE 12 control 40 Ml comonomer 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane, (CAS No. 2554-06-5) Alfa Aesar MOCOS (D.sup.Vi).sub.4 [00004] (D.sup.Vi).sub.4 Organic peroxide Luperox 26 Arkema t-butyl peroxy-2-ethylhexanoate Dicumyl peroxide (DCP) Farida, China Curing coagent Triallyl isocyanurate (TAIC) Farida, China Antioxidant Irganox 1076 BASF Antioxidant Cyanox 1790 BASF Antioxidant DSTDP Reagens, Inc. Antioxidant Uvinul 4050 BASF Propylene chain transfer agent Praxair

1. Polymerization of Ethylene and MOCOS Comonomer

[0146] The amount of each material used in the samples and in the comparative samples (controls) are provided in Table 2 below. A 545 milliliter (ml) stirred autoclave is charged with a mixture of ethylene, MOCOS ((D.sup.Vi).sub.4), propylene (as a chain transfer agent). Organic peroxide (Luperox 26) as a 0.5 wt %, 1 wt %, or 2 wt % solution in odorless mineral spirit was added as a polymerization initiator to the mixture, which was subjected to a set pressure of approximately 28,000 psi (1,969 kg/cm.sup.2). Reactor temperature was set to a target temperature of 220° C. Under the polymerization conditions shown in Table 2, ethylene/MOCOS copolymers were continuously synthesized and subsequently converted into pellet forms by melt extrusion. The conditions listed in Table 2 are averages over the time span that the samples were collected. The “autoclave-made” experimental reactor copolymers thus formed were found to have the characteristics set forth in Table 3.

TABLE-US-00002 TABLE 2 Polymerization Conditions Initiator Reactor Reactor Ethylene (D.sup.Vi).sub.4 Propylene Initiator solution Reactor Pressure Temperature feed rate feed rate feed rate solution feed rate conversion Example (psi) (° C.) (lb/hr) (lb/hr) (lb/hr) wt % (cc/hr) (%) 1 control 28000 220.4 25.0 0 0.93 1.0 22.5 8.69 2 control 27975 221.1 25.0 0 1.4 0.50 19.7 10.1 Sample 2 27987 220.1 25.0 0.12 0.98 0.50 45.6 9.93 Sample 3 28024 220.6 24.9 0.24 1.1 1.0 41.1 10.5 Sample 4 28013 220.9 25.0 0.40 1.2 2.0 27.9 8.72 Sample 10 27986 220.0 24.9 0.40 1.6 1.0 61.7 9.38 Sample 11 28048 219.6 24.9 0.12 0.95 1.0 22.6 10.1 Sample 13 28027 219.7 25.1 0.24 1.5 1.0 53.0 14.9

[0147] The properties of resultant ethylene/MOCOS copolymers are provided in Table 3 below.

TABLE-US-00003 TABLE 3 Properties for Ethylene/MOCOS Copolymer MI MI (D.sup.Vi).sub.4* target measured Vinyls.sup.+ Trans.sup.+ 1 control 0.0 4.0 4.15 0.3500 0.0522 2 control 0.0 40.0 40.46 0.5447 0.0755 Sample 2 0.15 4.0 3.51 0.3837 0.1283 Sample 3 0.3 4.0 3.47 0.4463 0.2043 Sample 4 0.50 4.0 2.85 0.5121 0.2984 Sample 10 0.50 40 14.66 0.6167 0.3008 Sample 11 0.08 4.0 3.46 0.3786 0.1014 Sample 13 0.30 40.0 37.25 0.6092 0.2307 NM = not measured, *wt % (D.sup.Vi).sub.4 and wt % MA based on total weight ethylene-based polymer composition, .sup.+Vinyls and trans are in mole %

TABLE-US-00004 TABLE 4 GPC Properties of ethylene/MOCOS copolymer Mw Conventional GPC Absolute GPC (Abs) Mw/ Mz Mz Mz + 1 Mz/ Mw ID* Mn Mw Mz Mp Mn Mn Mw (BB) (abs) (BB) Mw (GPC) 1 control(0/4) 11,471 82,089 410,969 41,675 7.16 11,976 182,857 886,632 6,210,161 1,986,555 33.96 2.23 2 control (0/40) 9,824 50,535 235,963 32,082 5.14 9,163 89,364 581,899 3,775,070 1,439,047 42.24 1.77 Sample 2 (0.15/4) 11,157 92,663 578,964 38,805 8.31 11,742 217,508 1,076,795 5,248,199 2,253,696 24.13 2.35 Sample 3 (0.30/4) 10,975 102,163 782,298 35,617 9.31 10,526 294,562 1,357,367 7,140,095 2,527,086 24.24 2.88 Sample 4 (0.50/4) 9,731 84,220 635,113 30,984 8.65 9,018 230,250 1,176,708 6,549,265 2,396,283 28.44 2.73 Sample 10 9,566 89,026 795,450 27,402 9.31 9,040 303,637 1,357,442 8,346,058 2,315,738 27.49 3.41 (0.50/40) Sample 11 (0.08/4) 11,984 90,702 528,185 39,741 7.63 12,089 213,760 1,033,855 5,597,665 2,163,215 26.19 2.36 Sample 13- 8,997 64,132 522,051 25,620 7.13 8,253 182,120 1,099,960 7,415,758 2,092,632 40.72 2.84 (0.30/40) *ID = Identification, wt % (D.sup.Vi).sub.4 is first value and MI is second value in closed parentheses

[0148] Proton NMR was used to characterize degree of incorporation/conversion of the (D.sup.Vi).sub.4 in selected samples. The Proton NMR detects the presence of Si—CH.sub.3 and Si-vinyl. On average, 2.5 double bonds per molecule of (D.sup.Vi).sub.4 are incorporated into the polyethylene backbone (Table 5). Bounded by no particular theory, it is believed that the copolymerization of the (D.sup.Vi).sub.4 with the ethylene and the incorporation of two double bonds produces H-branched structures resulting in an unexpected increase in melt strength.

TABLE-US-00005 TABLE 5 NMR data for ethylene/MOCOS copolymer Conversion NMR Si—CH.sub.3 NMR Si-vinyl (amount of per 1000 per 1000 double bonds Sample carbons carbons consumed, %) 2 0.41 0.15 63.4 3 0.76 0.26 65.7 4 1.28 0.44 65.6 10 1.21 0.43 64.4 11 0.23 0.08 65.2 13 0.72 0.27 62.5

2. Crosslinked Ethylene-based Polymer Composition

[0149] For the inventive examples (IE), dicumyl peroxide (DCP) and pellets of ethylene/MOCOS copolymer (and optional antioxidant) were weighed into in a 250 mL fluoride HDPE bottle. The bottle was then shaken for about 5 seconds (s) for mixing. Then the bottle was placed in an 80° C. oven. The bottle was then taken out every 5 minutes (min) for shaking (each shaking having a duration of about 5 seconds), totally 6 times at 0 min, 5min, 10 min, 15 min, 20 min, 25 min. The bottle was then shaken 5 times and then placed in the oven for 6.5 hours. MDR was then measured.

[0150] For the comparative samples (CS), DCP, pellets of LDPE and free (D.sup.Vi).sub.4 were weighed into in a 250 mL fluoride HDPE bottle. The bottle was then shaken for about 5 seconds (s) for mixing. Then the bottle was placed in an 80° C. oven. The bottle was then taken out every 5 minutes (min) for shaking (each shaking having a duration of about 5 seconds), totally 6 times at 0 min, 5min, 10 min, 15 min, 20 min, 25 min. The bottle was then shaken 5 times and then placed in the oven for 6.5 hours. MDR was then measured. In the comparative samples, no bonding occurs between the (D.sup.Vi).sub.4 and the LDPE.

TABLE-US-00006 TABLE 6A crosslinked ethylene-based polymer compositions ID* IE1 CS1 IE2 CS2 IE3 CS3 IE4 CS4 IE5 CS5 IE6 CS6 C1(0/4) C2 (0/40) 98 98.5 99 98.2 98.7 99.2 sample10 (0.5/40) 98.5 99 99.5 sample 13 (0.3/40) 98.5 99 99.5 sample 2 (0.15/4) sample11 (0.08/4) sample 4 (0.5/4) sample 3 (0.3/4) DCP 1.5 1.5 1 1 0.5 0.5 1.5 1.5 1 1 0.5 0.5 vi-d4 0.5 0.5 0.5 0.3 0.3 0.3 total 100 100 100 100 100 100 100 100 100 100 100 100 ML, dN*m 0.07 0.02 0.07 0.01 0.06 0.01 0.03 0.02 0.03 0.02 0.02 0.01 MH, dN*m 5.29 4.12 3.94 2.88 2.71 1.65 3.71 3.56 2.79 2.48 1.63 1.27 MH − ML, dN*m 5.22 4.1 3.87 2.87 2.65 1.64 3.68 3.54 2.76 2.46 1.61 1.26 T90, min. 3.69 4.22 3.82 4.54 4.37 5.34 4.27 4.42 4.50 4.68 4.79 5.72 gel content, % 89 85 85 80 78 71 85 84 81 77 73 58 *ID = Identification, wt % (D.sup.Vi).sub.4 is first value and MI is second value in closed parentheses, C = control,

TABLE-US-00007 TABLE 6B crosslinked ethylene-based polymer compositions (continued) ID* IE7 CS7 IE8 CS8 IE9 CS9 IE10 CS10 C1 (0/4) 99.35 98.42 98.92 98 C2 (0/40) s10 (0.5/40) s13 (0.3/40) s2 (0.15/4) 99.5 s11 (0.08/4) 98.5 99 s4 (0.5/4) 98.5 s3 (0.3/4) DCP 0.5 0.5 1.5 1.5 1 1 1.5 1.5 vi-d4 0.15 0.08 0.08 0.5 total 100 100 100 100 100 100 100 100 ML, dN*m 0.17 0.14 0.19 0.16 0.17 0.16 0.2 0.16 MH, dN*m 2.35 2.3 4.63 4.55 3.48 3.14 6.05 5.71 MH − ML, dN*m 2.18 2.16 4.44 4.39 3.31 2.98 5.85 5.55 T90, min. 4.42 4.56 4.02 4.13 4.06 4.21 3.48 3.70 gel content, % 76 69 88 86 82 80 89 90 ID* IE11 CS11 IE12 CS12 IE13 CS13 IE14 CS14 C1 (0/4) 98.2 98.5 99 99.2 C2 (0/40) s10 (0.5/40) s13 (0.3/40) s2 (0.15/4) s11 (0.08/4) s4 (0.5/4) 99 99.5 s3 (0.3/4) 98.5 99.5 DCP 1.5 1.5 1 1 1.5 0.5 0.5 0.5 vi-d4 0.3 0.5 0.5 0.3 total 100 100 100 100 100 100 100 100 ML, dN*m 0.18 0.16 0.18 0.15 0.16 0.14 0.15 0.14 MH, dN*m 5.32 5.11 4.73 4.43 3.33 3.08 2.69 2.54 MH − ML, dN*m 5.14 4.95 4.55 4.28 3.17 2.94 2.54 2.4 T90, min. 3.73 3.90 3.63 3.84 4.01 4.39 4.29 4.55 gel content, % 89 88 90 85 80 77 80 75 *ID = Identification, wt % (D.sup.Vi).sub.4 is first value and MI is second value in closed parentheses, C = control, S = sample

[0151] Tables 6A-6B show that the ethylene/(D.sup.Vi).sub.4 copolymer has higher crosslinking level (greater than 70% gel content) than is obtained using an equivalent amount of free (D.sup.Vi).sub.4 (vi-d4 in data tables) as an additive to LDPE. In the Tables 6A-6B, 7A-7B, 8, and 9, side-by-side comparisons are provided whereby each inventive example containing the ethylene/(D.sup.Vi).sub.4 copolymer with a given (D.sup.Vi).sub.4 wt % comonomer content is paired with a comparative sample composed of LDPE and free (D.sup.Vi).sub.4—the wt % (D.sup.Vi).sub.4 comonomer in the inventive example being the same as, or substantially the same as, the wt % of the free (D.sup.Vi).sub.4 in the comparative sample. Peroxide content is the same across each side-by-side comparison. For each side-by-side comparison, the inventive example has (i) a higher MH-ML value, and/or (ii) a shorter T90 time, and/or (iii) a greater percent gel content, and/or (iv) a lower hot creep value than the comparative sample.

[0152] Tables 7A-7B (below) show crosslinked compositions containing antioxidant Irganox 1076 (shown as 1076 in data tables).

TABLE-US-00008 TABLE 7A crosslinked ethylene-based polymer compositions with antioxidant ID* IE15 CS15 IE16 CS16 IE17 CS17 IE18 CS18 IE19 C1 (0/4) 98.8 97.8 99 98.5 C2 (0/40) s10 (0.5/40) s13 (0.3/40) s2 (0.15/4) s11 (0.08/4) s4 (0.5/4) 99.3 98.3 s3 (0.3/4) 99.3 98.8 98.3 DCP 0.5 0.5 1.5 1.5 0.5 0.5 1 1 1.5 Irganxo 1076 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 vi-d4 0.5 0.5 0.3 0.3 total 100 100 100 100 100 100 100 100 100 ML, dN*m 0.14 0.13 0.16 0.15 0.13 0.13 0.15 0.14 0.16 MH, dN*m 2.97 2.56 5.5 5.33 2.36 2.15 3.83 3.55 5.11 MH − ML, dN*m 2.83 2.43 5.34 5.18 2.23 2.02 3.68 3.41 4.95 T90, min. 3.98 4.46 3.64 3.90 4.23 4.62 4.02 4.15 3.83 gel content, % 76 72 88 88 72 68 82 79 87 ID* CS19 IE20 CS20 IE21 CS21 IE22 CS22 IE23 CS23 C1 (0/4) 98 99.15 98.65 99.22 98.22 C2 (0/40) s10 (0.5/40) s13 (0.3/40) s2 (0.15/4) 99.3 98.8 s11 (0.08/4) 99.3 98.3 s4 (0.5/4) s3 (0.3/4) DCP 1.5 1.5 0.5 1 1 0.5 0.5 1.5 1.5 Irganxo 1076 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 vi-d4 0.3 0.15 0.15 0.08 0.08 total 100 100 100 100 100 100 100 100 100 ML, dN*m 0.16 0.15 0.13 0.17 0.14 0.14 0.13 0.16 0.16 MH, dN*m 4.97 1.97 1.81 3.31 3.19 1.73 1.68 4.35 4.19 MH − ML, dN*m 4.81 1.82 1.68 3.14 3.05 1.59 1.55 4.19 4.03 T90, min. 4.03 4.62 4.73 4.22 4.44 4.91 5.09 4.15 4.30 gel content, % 87 68 60 80 77 66 55 85 84 *ID = Identification, wt % (D.sup.Vi).sub.4 is first value and MI is second value in closed parentheses, C = control, S = sample

TABLE-US-00009 TABLE 7B crosslinked ethylene-based polymer compositions with antioxidant (continued) ID* IE24 CS24 IE25 CS25 IE26 CS26 IE27 CS27 IE28 CS28 IE29 CS29 C1 (0/4) C2 (0/40) 98.8 98.3 97.8 98.5 98 s10 (0.5/40) 99.3 98.8 98.3 s13 (0.3/40) 99.3 98.8 98.3 s2 (0.15/4) s11 (0.08/4) s4 (0.5/4) s3 (0.3/4) DCP 0.5 0.5 1 1 1.5 1.5 0.5 0.5 1 1 1.5 1.5 Irganox 1076 0.2 0.2 0.2 0.2 0.2 3.2 0.2 0.2 0.2 0.2 0.2 0.2 vi-d4 0.5 0.5 0.5 0.3 0.3 0.3 total 100 100 100 100 100 100 100 100 100 100 100 100 ML, dN*m 0.05 0.01 0.06 0.01 0.06 0.01 0.01 0.01 0.03 0.01 0.02 0.02 MH, dN*m 2.2 1.27 3.44 2.41 4.59 3.7 1.26 0.95 2.47 2.04 3.4 3.23 MH − ML, dN*m 2.15 1.26 3.38 2.4 4.53 3.69 1.25 0.94 2.44 2.03 3.38 3.21 T90, min. 4.41 5.39 3.99 4.62 3.87 4.47 5.24 5.43 4.51 4.98 4.40 4.68 gel content, % 71 65 81 72 87 83 64 56 78 72 83 81 *ID = Identification, wt % (D.sup.Vi).sub.4 is first value and MI is second value in closed parentheses, C = control

TABLE-US-00010 TABLE 8 Hot creep data for crosslinked compositions IE 30 CS 30 IE 16 CS 16 IE18 CS18 IE 19 CS 19 IE 31 CS31 IE 23 CS 23 Control sample 1 98.3 97.8 98.5 98 98.15 98.22 (MI = 4) 0.5% vi-d4 copolymer 98.8 98.3 (Sample 4, MI = 4) 0.3% vi-d4 copolymer 98.8 98.3 (Sample 3, MI = 4) 0.15% vi-d4 copolymer 98.3 (Sample 2, MI = 4) 0.08% vi-d4 copolymer 98.3 (Sample 11, MI = 4) DCP 1 1 1.5 1.5 1 1 1.5 1.5 1.5 1.5 1.5 1.5 Irganox 1076 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Vinyl D4 0.5 0.5 0.3 0.3 0.15 0.08 TAIC AO blends* Total 100 100 100 100 100 100 100 100 100 100 100 100 Hot creep elongation % 50 93 30 45 80 155 47 53 72 77 82 128

TABLE-US-00011 TABLE 9 Hot creep data for crosslinked compositions (continued) IE 32 IE 33 IE 34 CS 32 Control Sample 1 (MI = 4) 98.35 0.15% vi-d4 copolymer 98.85 98.55 98.5 (Sample 2, MI = 4) DCP 0.5 0.3 0.3 0.3 Vinyl D4 0.5 1 0.6 0.75 TAIC — — 0.45 0.45 AO blend* 0.15 0.15 0.15 0.15 Total 100 100 100 100 Hot creep elongation % 110 112 85 143 ML, dN*m 0.14 0.12 0.13 0.12 MH, dN*m 2.85 2.41 2.63 2.53 MH − ML, dN*m 2.71 2.29 2.50 2.41 T90, min. 4.40 5.21 5.25 5.55 *0.15% AO blend = antioxidant blend 0.06% Cyanox 1790, .09% DSTDP and 19 ppm of Uvinul 4050 (for aggregate 0.15 wt % based on total wt of crosslinkable ethylene-based polymer composition)

[0153] The hot creep data from Tables 8-9 (above) show that crosslinked ethylene-based polymer compositions with the ethylene/MOCOS copolymer exhibit improved hot creep performance (i.e., shorter hot creep elongation %) than the comparative samples (control formulations). The data demonstrate the advantage for using ethylene/MOCOS copolymer composition in order to achieve a desired crosslinking level.

[0154] Comparing IE34 (ethylene/(0.15 wt %) MOCOS copolymer with 0.6 wt % free (D.sup.Vi).sub.4) to CS32 (LDPE and 0.75 wt % free (D.sup.Vi) shows IE34 achieved better curing response with shorter T90 time (5.25 v 5.55), lower hot creep (85% v 143%), higher MH-ML (2.50 v 2.41) at the same (D.sup.Vi).sub.4, weight percent (0.15 wt %) and same amount of DCP (0.3 wt %).

[0155] It is specifically intended that the present disclosure not be limited to the embodiments and illustrations contained herein, but include modified forms of those embodiments including portions of the embodiments and combinations of elements of different embodiments as come within the scope of the following claims.