Masterbatch with semi-crystalline polyolefin carrier resin

Abstract

A coagent masterbatch comprising a semi-crystalline polyolefin carrier resin and an alkenyl-functional coagent. An electron-beam curable formulation comprising the coagent masterbatch and a polyolefin compound. A method of making the master-batch and formulation; an electron-beam-cured polyolefin product prepared therefrom; a manufactured article comprising or made from the masterbatch, formulation, or product; and a method of using the manufactured article.

1 . A coagent masterbatch comprising (A) a semi-crystalline polyolefin carrier resin and (B) an alkylene-functional coagent disposed in the (A) semi-crystalline polyolefin carrier resin; wherein (A) is 80.0 to 99.9 weight percent (wt %) and (B) is from 20.0 to 0.1 wt % of the combined weight of constituents (A) and (B); wherein the (A) semi-crystalline polyolefin carrier resin has a crystallinity of from 55.0 to less than 100 weight percent (wt %) as measured by Crystallinity Test Method using differential scanning calorimetry (DSC); wherein when the (A) semi-crystalline polyolefin carrier resin is a semi-crystalline polyethylene, the semi-crystalline polyethylene has a density of greater than 0.935 gram per cubic centimeter (g/cm 3 ). 
     
     
         2 . The coagent masterbatch of  claim 1  characterized by any one of limitations (i) to (x): (i) the coagent masterbatch is free of (C) an (electron beam)-curable polyolefin compound (host polymer) other than constituent (A); (ii) the coagent masterbatch further comprises at least one additive independently selected from optional additives (D) to (L): (D) a flame retardant, (E) an antioxidant, (F) a processing aid, (G) a colorant, (H) a metal deactivator, (I) an (unsaturated carbon-carbon bond)-free hydrolyzable silane, (J) a corrosion inhibitor, (K) a hindered amine light stabilizer, and (L) an ethylene-based copolymer that is different than constituents (A) and (C) and is an ethylene/(C 4 -C 20 )alpha-olefin copolymer, an ethylene/unsaturated carboxylic ester copolymer, or a propylene/ethylene-based copolymer; (iii) the coagent masterbatch does not contain an alkenyl-functional coagent-containing porous resin; (iv) the coagent masterbatch does not contain any porous resin; (v) the coagent masterbatch consists of constituents (A) and (B);
 (vi) both (i) and (ii); (vii) both (i) and (iii); (viii) both (i) and (iv); (ix) the coagent masterbatch can be maintained for at least 20 days at a temperature of 23° C. without sweat out of the alkenyl-functional coagent as measured by Sweat Out Test Method (Quantitative); and (x) both (ix) and any one of (i) to (viii). 
 
     
     
         3 . The coagent masterbatch of  claim 1  wherein the (A) semi-crystalline polyolefin carrier resin comprises any one of (i) to (viii): (i) a semi-crystalline medium density polyethylene; (ii) a semi-crystalline high density polyethylene; (iii) a semi- crystalline polypropylene; (iv) a semi-crystalline ethylene/propylene copolymer; (v) a semi-crystalline poly(ethylene-co-alpha-olefin) copolymer; (vi) a combination of any two or more of (i), (ii) and (v); (vii) the (A) semi-crystalline polyolefin carrier resin has a crystallinity of 57.5 to <100 wt % (Crystallinity Test Method using DSC); or (viii) limitation (vii) and any one of limitations (i) to (vi). 
     
     
         4 . The coagent masterbatch of  claim 1  wherein the (A) semi-crystalline polyolefin carrier resin has any one of (i) to (viii): (i) a density of greater than 0.936 g/cm 3  and is a polyethylene; (ii) a density of 0.89 to 0.946 g/cm 3  and is a polypropylene; (iii) a crystallinity of 60.0 to <100 wt % (Crystallinity Test Method using DSC) and is a polyethylene; (iv) a melt index (I 2 , 190° C./2.16 kg load) of 0.1 to 20 grams per 10 minutes (g/10 min) measured according to the Melt Index Test Method and is a polyethylene or a melt flow rate (MFR) of 0.5 to 20 g/10 min. (230° C./2.16 kg load) measured according to the Melt Flow Rate Test Method and is a polypropylene; (v) a molecular weight distribution (MWD) that is monomodal; (vi) a MWD that is multimodal; (vii) wherein the combined weight of constituents (A) and (B) is from 50 to 100 wt % of the coagent masterbatch; (viii) any two or limitations (i) to (vii). 
     
     
         5 . The coagent masterbatch of  claim 1  wherein the (B) alkenyl-functional coagent is as described by any one of limitations (i) to (viii): (i) (B) is 2-allylphenyl allyl ether; 4-isopropenyl-2,6-dimethylphenyl allyl ether; 2,6-dimethyl-4-allylphenyl allyl ether; 2-methoxy-4-allylphenyl allyl ether; 2,2′-diallyl bisphenol A; O,O′-diallyl bisphenol A; or tetramethyl diallylbisphenol A; (ii) (B) is 2,4-diphenyl-4-methyl-1-pentene or 1,3-diisopropenylbenzene; (iii) (B) is triallyl isocyanurate; triallyl cyanurate; triallyl trimellitate; N,N,N′,N′,N″,N″-hexaallyl-1,3,5-triazine-2,4,6-triamine; triallyl orthoformate;
 pentaerythritol triallyl ether; triallyl citrate; or triallyl aconitate; (iv) (B) is trimethylolpropane triacrylate, trimethylolpropane trimethylacrylate, ethoxylated bisphenol A dimethacrylate, 1,6-hexanediol diacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, tris(2-hydroxyethyl) isocyanurate triacrylate, or propoxylated glyceryl triacrylate; (v) (B) is a polybutadiene having at least 50 wt % 1,2-vinyl content or trivinyl cyclohexane; (vi) (B) is an alkenyl-functional organosiloxane of formula (I): [R 1 ,R 2 SiO 2/2 ] n  (I), wherein subscript n is an integer greater than or equal to 3; each R 1  is independently a (C 2 -C 4 )alkenyl or a H 2 C=C(R 1a )—C(=O)—O—(CH 2 ) m - wherein R 1a  is H or methyl and subscript m is an integer from 1 to 4; and each R 2  is independently H, (C 1 -C 4 )alkyl, phenyl, or R 1 ; (vii) (B) is an alkenyl-functional monocyclic organosiloxane of formula (II): (R 1 ) x Si(OR 2 )( 4-x ) (II), wherein subscript x is an integer from 0 to 4; each R 1  is independently a (C 2 -C 4 )alkenyl or a H 2 C=C(R 1a )—C(=O)—O—(CH 2 ) m - wherein R 1a  is H or methyl and subscript m is an integer from 1 to 4; and each R 2  is independently H, (C 1 -C 4 )alkyl, phenyl, or R 1 ; with the proviso that the alkenyl-functional monocyclic organosiloxane of formula (II) contains from 2 to 4 R 1  groups; (viii) a combination or any two or more of (i) to (vii). 
 
     
     
         6 . A method of storing a coagent masterbatch, the method comprising maintaining for at least 20 days the coagent masterbatch of  claim 1  at a temperature from 20° to 25° C. to give a stored coagent masterbatch without sweat out of the alkenyl-functional coagent as measured by Sweat Out Test Method (Quantitative). 
     
     
         7 . An (electron beam)-curable formulation comprising the coagent masterbatch of  claim 1 , or the stored coagent masterbatch made by the method of  claim 6 , and (C) an electron-beam curable (EBC) polyolefin compound. 
     
     
         8 . The (electron beam)-curable formulation of  claim 7  characterized by any one of limitations (i) to (xiii): (i) the (C) EBC polyolefin compound is a low density polyethylene (LDPE) having a density from 0.910 to 0.925 g/cm 3 ; (ii) the (C) EBC polyolefin compound is a linear low density polyethylene (LLDPE) having a density from 0.910 to 0.925 g/cm 3 ; (iii) the (C) EBC polyolefin compound is a medium density polyethylene (MDPE) having a density from 0.926 to 0.940 g/cm 3 ; (iv) the (C) EBC polyolefin compound is a high density polyethylene (HDPE) having a density from 0.941 to 0.990 g/cm 3 ; (v) the (C) EBC polyolefin compound is a polyethylene elastomer selected from an ethylene-propylene rubber (EPR), ethylene-1-butene rubber (EBR), and ethylene- 1-octene rubber (EOR); (vi) the (C) EBC polyolefin compound is an ethylene/(C 3 -C 20 )alpha-olefin) copolymer; (vii) the (C) EBC polyolefin compound is an ethylene-propylene copolymer (EPP); (viii) the (C) EBC polyolefin compound is an ethylene-propylene-diene monomer (EPDM) copolymer; (ix) the (C) EBC polyolefin compound is a combination of any two or more of (i) to (viii); (x) the (electron beam)-curable formulation further comprises at least one additive that is not a constituent of the coagent masterbatch and is independently selected from optional additives (D) to (L): (D) a flame retardant, (E) an antioxidant, (F) a processing aid, (G) a colorant, (H) a metal deactivator, (I) an (unsaturated carbon-carbon bond)-free hydrolyzable silane, (J) a corrosion inhibitor, (K) a hindered amine light stabilizer, and (L) an ethylene-based copolymer additive that is different than constituents (A) and (C) and is an ethylene/(C 4 -C 20 )alpha-olefin copolymer, an ethylene/unsaturated carboxylic ester copolymer, or a propylene/ethylene-based copolymer; (xi) limitation (x) and any one of limitations (i) to (viii); (xii) (B) is from 0.1 to 20 wt % of the combined weight of constituents (A), (B) and (C); and (xiii) limitation (xii) and any one of limitations (i) to (xi). 
     
     
         9 . A method of making an (electron beam)-curable formulation, the method comprising mixing together a divided solid form of the coagent masterbatch of  claim 1 , and a (C) EBC polyolefin compound in divided solid or melt form so as to give a mixture; and melt mixing or extruding the mixture so as to make the (electron beam)-curable (EBC) formulation. 
     
     
         10 . A method of electron-beam curing a formulation in need thereof, the method comprising irradiating the EBC formulation of  claim 7 , with an effective dose of electron-beam irradiation so as to give an electron-beam cured polyolefin product. 
     
     
         11 . An electron-beam-cured polyolefin product made by the method of  claim 10 . 
     
     
         12 . A manufactured article comprising the electron-beam-cured polyolefin product of  claim 11  and a component in operative contact therewith. 
     
     
         13 . A coated conductor comprising a conductive core and a polymeric layer at least partially surrounding the conductive core, wherein at least a portion of the polymeric layer comprises the electron-beam-cured polyolefin product of  claim 11 . 
     
     
         14 . A method of conducting electricity, the method comprising applying a voltage across the conductive core of the coated conductor of  claim 13  so as to generate a flow of electricity through the conductive core.