阅读说明：本技术 聚烯烃组合物 (Polyolefin compositions ) 是由 张楷男 孙亚斌 J·M·柯吉恩 T·J·珀森 于 2017-09-18 设计创作，主要内容包括：一种聚烯烃组合物,其包含聚烯烃聚合物、烯基官能的单环有机硅氧烷和有机过氧化物；和由所述聚烯烃组合物制备的产物；制备和使用所述聚烯烃组合物的方法；以及含有所述聚烯烃组合物的物品。(A polyolefin composition comprising a polyolefin polymer, an alkenyl-functional monocyclic organosiloxane, and an organic peroxide; and a product prepared from the polyolefin composition; methods of making and using the polyolefin compositions; and articles comprising the polyolefin composition.)

1. A polyolefin composition comprising (a) a polyolefin polymer which is a Low Density Polyethylene (LDPE) polymer comprising: 50 to 100 weight percent (wt%) of an ethylenic monomer unit, 50 to 0 wt% (C)₃-C₂₀) α -olefin derived comonomer units, and 20 to 0 wt% of diene comonomer units, wherein the total weight percent is 100.00 wt%, (B) a monocyclic organosiloxane of the formula (I)R¹,R²SiO_2/2]_n(I) Wherein subscript n is an integer greater than or equal to 3; each R¹Independently is (C)₂-C₄) Alkenyl or H₂C＝C(R^1a)-C(＝O)-O-(CH₂)_m-, wherein R^1aIs H or methyl, and subscript m is an integer of 1 to 4; and each R²Independently H, (C)₁-C₄) Alkyl, phenyl or R¹(ii) a And (C) an organic peroxide; with the proviso that the polyolefin composition does not contain a phosphazene base.

2. A polyolefin composition comprising (a) a polyolefin polymer which is a Low Density Polyethylene (LDPE) polymer comprising: 50 to 100 weight percent (wt%) of an ethylenic monomer unit, 50 to 0 wt% (C)₃-C₂₀) α -olefin derived comonomer units, and 20 to 0 wt% of diene comonomer units, wherein the total weight percentage is 100.00 wt%, (B) a monocyclic organosiloxane of the formula (I) [ R¹,R²SiO_2/2]_n(I) Wherein subscript n is an integer greater than or equal to 3; each R¹Independently is (C)₂-C₄) Alkenyl or H₂C＝C(R^1a)-C(＝O)-O-(CH₂)_m-, wherein R^1aIs H or methyl, and subscript m is an integer of 1 to 4; and each R²Independently H, (C)₁-C₄) Alkyl, phenyl or R¹(ii) a And (C) an organic peroxide; with the proviso that the polyolefin composition is free of phosphazene base; and with the proviso that when subscript n is 4, said (a) polyolefin composition does not contain 24 wt% or more of an inorganic filler selected from the group consisting of: alumina, aluminum silicate, calcium silicate, magnesium silicate, silicon dioxide, titanium dioxide, and mixtures thereof.

3. The polyolefin composition according to claim 1 or 2 wherein subscript n is 3 and the (B) monocyclic organosiloxane of formula (I) is described by any one of the following limitations (I) to (x): (i) each R¹Independently is (C)₂-C₃) Alkenyl radical(ii) a And each R²Independently H, (C)₁-C₂) Alkyl or (C)₂-C₃) An alkenyl group; (ii) each R¹Is a vinyl group; and each R²Independently is (C)₁-C₂) An alkyl group; (iii) each R¹Is a vinyl group; and each R²Is methyl; (iv) each R¹Is allyl; and each R²Independently is (C)₁-C₂) An alkyl group; (v) each R¹Is allyl; and each R²Is methyl; (vi) each R¹Independently is H₂C＝C(R^1a)-C(＝O)-O-(CH₂)_m-, wherein R^1aIs H or methyl, and subscript m is an integer of 1 to 4; and each R²Independently H, (C)₁-C₂) Alkyl or (C)₂-C₃) An alkenyl group; (vii) each R¹Independently is H₂C＝C(R^1a)-C(＝O)-O-(CH₂)_m-, wherein R^1aIs H and subscript m is 3; and each R²Independently is (C)₁-C₂) An alkyl group; (viii) each R¹Independently is H₂C＝C(R^1a)-C(＝O)-O-(CH₂)_m-, wherein R^1aIs methyl and subscript m is 3; and each R²Independently is (C)₁-C₂) An alkyl group; (ix) the polyolefin composition does not contain 24 wt% or more of an inorganic filler selected from the group consisting of: alumina, aluminum silicate, calcium silicate, magnesium silicate, silicon dioxide, titanium dioxide, and mixtures thereof; and (x) a combination of limit (ix) and any one of limits (i) to (viii).

4. The polyolefin composition according to claim 1 or 2 wherein subscript n is 4 and the (B) monocyclic organosiloxane of formula (I) is described by any one of the following limitations (I) to (x): (i) each R¹Independently is (C)₂-C₃) An alkenyl group; and each R²Independently H, (C)₁-C₂) Alkyl or (C)₂-C₃) An alkenyl group; (ii) each R¹Is a vinyl group; and each R²Independently is (C)₁-C₂) An alkyl group; (iii) each R¹Is a vinyl group; and each R²Is methyl; (iv) each R¹Is allyl; and each R²Independently is (C)₁-C₂) An alkyl group; (v) each R¹Is allyl; and each R²Is methyl; (vi) each R¹Independently is H₂C＝C(R^1a)-C(＝O)-O-(CH₂)_m-, wherein R^1aIs H or methyl, and subscript m is an integer of 1 to 4; and each R²Independently H, (C)₁-C₂) Alkyl or (C)₂-C₃) An alkenyl group; (vii) each R¹Independently is H₂C＝C(R^1a)-C(＝O)-O-(CH₂)_m-, wherein R^1aIs H and subscript m is 3; and each R²Independently is (C)₁-C₂) An alkyl group; (viii) each R¹Independently is H₂C＝C(R^1a)-C(＝O)-O-(CH₂)_m-, wherein R^1aIs methyl and subscript m is 3; and each R²Independently is (C)₁-C₂) An alkyl group; (ix) the polyolefin composition does not contain 24 wt% or more of any inorganic filler; and (x) a combination of limit (ix) and any one of limits (i) to (viii).

5. The polyolefin composition according to claim 1 or 2 wherein subscript n is 5 or 6 and the (B) monocyclic organosiloxane of formula (I) is described by any one of the following limitations (I) to (x): (i) each R¹Independently is (C)₂-C₃) An alkenyl group; and each R²Independently H, (C)₁-C₂) Alkyl or (C)₂-C₃) An alkenyl group; (ii) each R¹Is a vinyl group; and each R²Independently is (C)₁-C₂) An alkyl group; (iii) each R¹Is a vinyl group; and each R²Is methyl; (iv) each R¹Is allyl; and each R²Independently is (C)₁-C₂) An alkyl group; (v) each R¹Is allyl; and each R²Is methyl; (vi) each R¹Independently is H₂C＝C(R^1a)-C(＝O)-O-(CH₂)_m-, wherein R^1aIs H or methyl, and subscript m is an integer of 1 to 4; and each R²Independently H, (C)₁-C₂) Alkyl or (C)₂-C₃) An alkenyl group; (vii) each R¹Independently is H₂C＝C(R^1a)-C(＝O)-O-(CH₂)_m-, wherein R^1aIs H and subscript m is 3; and each R²Independently is (C)₁-C₂) An alkyl group; (viii) each R¹Independently is H₂C＝C(R^1a)-C(＝O)-O-(CH₂)_m-, wherein R^1aIs methyl and subscript m is 3; and each R²Independently is (C)₁-C₂) An alkyl group; (ix) the polyolefin composition does not contain 24 wt% or more of an inorganic filler selected from the group consisting of: alumina, aluminum silicate, calcium silicate, magnesium silicate, silicon dioxide, titanium dioxide, and mixtures thereof; and (x) a combination of limit (ix) and any one of limits (i) to (viii).

6. The polyolefin composition according to any one of claims 1 to 5, which is described by limiting any one of (i) to (vii): (i) the polyolefin polymer (A) is characterized by a density of 0.86 to 0.97 grams per cubic centimeter (g/cm)³) As measured in 2-propanol by method B of ASTM D792-13; (ii) the (a) polyolefin polymer is 80 to 99.89 weight percent (wt%) of the weight of the polyolefin composition; (iii) the (B) monocyclic organosiloxane of formula (I) is 0.1 to 3 wt% of the polyolefin composition; and the (C) organic peroxide is 0.01 to 4.5 wt% of the polyolefin composition; (iv) both (i) and (ii); (v) (ii) both (i) and (iii); (vi) both (ii) and (iii); and (vii) each of (i), (ii), and (iii).

7. The polyolefin composition according to any of claims 1 to 6, additionally comprising at least one additive selected from the group consisting of: (D) conventional auxiliaries; (E) an antioxidant; (F) a filler; (G) a flame retardant; (H) a hindered amine stabilizer; (I) an anti-tree agent; (J) a methyl radical scavenger; (K) a scorch retarder, (L) a nucleating agent, and (M) carbon black; with the proviso that the total amount of the at least one additive is >0 to 70 wt% of the polyolefin composition and with the proviso that the (F) filler does not comprise any omitted filler.

8. A method of preparing a polyolefin composition, the method comprising reacting (a) a polyolefin polymer and (B) a monocyclic organosiloxane of formula (I): [ R ]¹,R²SiO_2/2]_n(I) Mixing together to prepare the polyolefin composition according to any one of claims 1 to 6.

9. A process for radically curing a polyolefin composition according to any of claims 1 to 7 to produce a crosslinked polyolefin product, the process comprising heating the polyolefin composition with (C) an organic peroxide at a curing effective temperature in such a way that (a) a polyolefin polymer is reacted with (B) a monocyclic organosiloxane of formula (I) to produce a crosslinked polyolefin product.

10. A crosslinked polyolefin product prepared by the method of curing according to claim 9.

11. An article comprising the polyolefin composition according to any one of claims 1 to 8 or the crosslinked polyolefin product according to claim 10 in shaped form.

12. A coated conductor comprising a conductive core and an insulating layer at least partially covering the conductive core, wherein at least a portion of the insulating layer comprises the polyolefin composition of any one of claims 1 to 7 or the crosslinked polyolefin product of claim 10.

13. A method of transmitting electricity, the method comprising applying a voltage across a conductive core of the coated conductor of claim 12 so as to generate a current through the conductive core.

Technical Field

Included within the scope are polyolefin compositions, products made therefrom, methods of making and using the same, and articles containing the same.

Cross Reference to Related Applications

This application claims benefit of priority from PCT international patent application number PCT/CN2017/090770, filed on 29/6/2017, and is incorporated herein by reference in its entirety.

Background

Insulated electrical conductors typically comprise a conductive core covered by an insulating layer. The conductive core may be solid or stranded (e.g., a bundle of wires). Some insulated electrical conductors may also contain one or more additional elements, such as one or more semiconductive layers and/or a protective jacket (e.g., a wire wrap, tape, or sheath). Examples are coated metal wires and power cables, including metal wires and power cables used in low voltage ("LV", >0 to <5 kilovolts (kV)), medium voltage ("MV", 5 to <69kV), high voltage ("HV", 69 to 230kV) and extra high voltage ("EHV", >230kV) transmission/distribution applications. The evaluation of the power cable may use the AEIC/ICEA standard and/or the IEC test method.

US 4,005,254 ("MacKenzie") to b.t. MacKenzie, jr. relates to pressureless curing systems for chemically crosslinking ethylene-containing polymers, and products formed therefrom. The curable composition comprises an ethylene-containing polymer, a curing agent, and a mineral filler treated with tetramethyltetravinylcyclotetrasiloxane. In preparing the composition, the polymer, mineral filler, tetramethyltetravinylcyclotetrasiloxane and other additives are intimately blended as in a Banbury mixer. During this compounding operation, the tetramethyltetravinylcyclotetrasiloxane is said to interact with or coat the filler, and the result is referred to as a siloxane-treated filler. If desired, the mineral filler may be pretreated with tetramethyltetravinylcyclotetrasiloxane in a separate operation, and the siloxane-treated filler is then blended with the polymer and other additives. The MacKenzie toluene extract (% of compound) data for example 1(0.0 weight percent (wt%) tetramethyltetravinylcyclotetrasiloxane) is 11.6%, and the MacKenzie toluene extract data for examples 2 and 3 (0.97 wt% tetramethyltetravinylcyclotetrasiloxane, respectively, by weight of the composition) is 9.6% and 11.8%, respectively (table I). Considering the percent extractables of comparative example 1 versus examples 2 and 3, one skilled in the art will recognize that the tetramethyltetravinylcyclotetrasiloxane of examples 2 and 3 does not contribute to the crosslinking of the ethylene-containing polymer. In contrast, tetramethyltetravinylcyclotetrasiloxane coats the aluminum silicate filler as taught by MacKenzie.

US 8,426,519B2 to j.m. cogen et al relates to silicone-thermoplastic polymer reactive blends and copolymer products prepared using economical post-reactor reactive mixing, such as extrusion. The procedure is based on the ring-opening polymerization of cyclic siloxanes in a thermoplastic polymer matrix. In a preferred mode, the thermoplastic polymer is a polyolefin, optionally containing silane groups available for reaction with an in situ-forming silicone polymer. The resulting material provides hybrid properties and can extend the range of applications beyond that provided by thermoplastic polymers or silicones alone or physical blends thereof.

CN104277182A to Z-l Wu et al and the article "Cross-linking of Low Density polyethylene with octavinyl polyhedral oligomeric silsesquioxane as a cross-linker" J.Wu et al, "RSC Advances in the British society of Industrial chemistry (RSC Advances), 2014, vol.4, page 44030 relate to a process for preparing cross-linked low density polyethylene using octavinyl polyhedral oligomeric silsesquioxane as a cross-linker.

Disclosure of Invention

We recognize the problem of compromising the crosslinking and performance of existing polyolefins. Coagents can be blended with polyolefins to obtain polyolefin compositions with increased crosslinking capability, but conventional coagents have their limitations. For example, conventional adjuvants are often limited in solubility or miscibility in polyolefin compositions. This limits the maximum loading level of adjuvant in the composition. It also allows the adjuvant to migrate improperly to the surface of the composition (e.g., the surface of the pellet), thereby limiting the shelf life of the composition. Conventional adjuvants also pose other problems. For example, they may produce crosslinked products that are insufficiently crosslinked after curing. Alternatively, the composition may cure too slowly for certain manufacturing operations (e.g., power cable manufacturing, injection molding, and film extrusion). Alternatively, the composition may cure prematurely (i.e., scorch easily during cable extrusion, injection molding, and film extrusion). Not surprisingly, these problems limit the structure of conventional auxiliaries that have been used with polyolefins. Typically, conventional adjuvants comprise a conventional substructure group bonded to two or more ethylenic crosslinking groups. Conventional substructural groups are acyclic or cyclic multivalent groups comprising a backbone or a ring, respectively, which contain carbon atoms and optionally nitrogen and/or oxygen atoms in the backbone or ring, but no silicon atoms.

This problem compromises the performance of power cables operating at higher voltages. Scorching can occur during extrusion of the insulation layer and ultimately lead to failure of the insulation layer. By using a more resilient material in the insulating layer, the time to reach such failure can be extended and thus the reliability of the power transmission is improved and the maintenance costs are reduced.

The technical solution to this problem is not obvious from the prior art. Then, the problem to be solved by the inventiveness was to find a new polyolefin composition comprising a polyolefin polymer and an improved auxiliary agent, wherein the polyolefin composition as well as the cured crosslinked product thereof can be used as an insulation layer in a power cable (HV or EHV power cable) at high voltage. Our analysis shows that the new adjuvants are ideally cyclic molecules, which do not contain carbon or nitrogen atoms in the ring.

Our technical solutions to this problem include: a polyolefin composition comprising a polyolefin polymer and an alkenyl-functional monocyclic organosiloxane; a crosslinked polyolefin product prepared therefrom; methods of making and using the same; and articles containing the same.

The polyolefin compositions and products of the invention can be used in any application that utilizes polyolefins, including crosslinked polyolefins, including extruded articles, coatings, films, sheets, and injection molded articles, as well as in electrical transmission applications and other unrelated applications such as containers or vehicle parts.

Detailed Description