Compositions comprising a substantially random interpolymer of at least one alpha-olefin and at least one vinylidene aromatic monomer or hindered aliphatic vinylidene monomer

Abstract

Disclosed are compositions comprising at least one substantially random interpolymer of ethylene and a vinylidene aromatic monomer or a hindered aliphatic vinylidene monomer and optionally at least one C 3 -C 20 α-olefin monomer, and at least one tackifier. The claimed compositions are useful in adhesives, such as are employed in various applications, such as in packaging and carton sealing, bookbinding, masking tape, clear office tape, labels, decals, bandages, decorative and protective sheets (such as shelf and drawer liners), floor tiles, sanitary napkin/incontinence device placement strips, sun control films, and the joining of gaskets to automobile windows. The claimed compositions further find use in a variety of applications, such as sealants, coatings, molded articles, and multilayered structures.

1 . A composition comprising from 5 to 95 weight percent of at least one substantially random interpolymer of ethylene and a vinylidene aromatic monomer or a hindered aliphatic vinylidene monomer and optionally at least one C 3 -C 20  α-olefin monomer, wherein the substantially random interpolymer comprises from 1-65 mole percent of the vinylidene aromatic monomer or hindered aliphatic vinylidene monomer, and from 5 to 95 weight percent of at least one tackifier.  
     
     
         2 . The composition of  claim 1 , wherein the at least one substantially random interpolymer is an interpolymer of ethylene and a vinylidene aromatic monomer represented by the following formula:  
       
         
           
           
               
               
           
         
       
       wherein R 1  is selected from the group of radicals consisting of hydrogen and alkyl radicals containing three carbons or less, and Ar is a phenyl group or a phenyl group substituted with from 1 to 5 substituents selected from the group consisting of halo, C 1-4  alky, and C 1-4  haloalkyl.  
     
     
         3 . The composition of  claim 1 , wherein the substantially random interpolymer is an interpolymer of ethylene, a vinylidene aromatic monomer or a hindered aliphatic vinylidene monomer, and at least one third monomer selected from the group consisting of C 3 -C 20  α-olefins and norbornene.  
     
     
         4 . The compositions of  claim 1 , wherein the substantially random interpolymer is an interpolymer of ethylene, a vinylidene aromatic monomer, and optionally at least one third monomer selected from the group consisting of C 3 -C 20  α-olefins and norbornene.  
     
     
         5 . The composition of  claim 1 , wherein the composition comprises from 25 to 95 weight percent of the substantially random interpolymer and from 5 to 75 weight percent of at least one tackifier.  
     
     
         6 . The composition of  claim 1 , wherein the at least one tackifier is selected from the group consisting of wood rosin, tall oil derivatives, cyclopentadiene derivatives, natural and synthetic terpenes, terpene-phenolics, styrene/α-methyl styrene resins, and mixed aliphatic-aromatic tackifying resins.  
     
     
         7 . The composition of  claim 1 , wherein the composition further comprises from 5 to 75 weight percent of at least one modifying or extending composition selected from the group consisting of paraffinic waxes, crystalline polyethylene waxes, ultralow molecular weight ethylene polymers, homogeneous linear or substantially linear ethylene/α-olefin interpolymers, polystyrene, styrene block copolymers, ethylene vinyl acetate, and amorphous polyolefins.  
     
     
         8 . The composition of  claim 1 , wherein the composition comprises from 1 to 60 weight percent of one or more processing aids selected from the group consisting of phthalate esters, natural oils, paraffinic oils, naphthenic oils, and aromatic oils.  
     
     
         9 . The composition of  claim 1 , in the form of an adhesive, layer of a multilayer food packaging structure, coating, sealant or molded article, calendared article, or extruded article.  
     
     
         10 . An adhesive which comprises from 5 to 95 weight percent of at least one substantially random interpolymer of ethylene and a vinylidene aromatic monomer or a hindered aliphatic vinylidene monomer and optionally at least one C 3 -C 20  α-olefin monomer, wherein the substantially random interpolymer comprises from 1-65 mole percent of the vinylidene aromatic monomer or hindered aliphatic vinylidene monomer, and wherein the adhesive further comprises from 95 to 5 weight percent of at least one second component selected from the group consisting of tackifiers, waxes, homogeneous linear or substantially linear ethylene/α-olefin interpolymers, ultra-low molecular weight ethylene polymers, processing aids, and mixtures thereof.  
     
     
         11 . The adhesive of  claim 10 , wherein the substantially random interpolymer comprises from 25 to 65 weight percent of the vinylidene aromatic monomer or hindered aliphatic vinylidene monomer.  
     
     
         12 . The adhesive of  claim 10 , wherein the adhesive comprises a plurality of substantially random interpolymer components which differ in the amount of vinylidene aromatic monomer or hindered aliphatic vinylidene monomer content, which differ in molecular weight, or which differ in both the amount of vinylidene aromatic monomer or hindered aliphatic vinylidene monomer content and in molecular weight.  
     
     
         13 . The adhesive of  claim 12 , which comprises: 
 (a) 5 to 75 weight percent of a substantially random interpolymer of ethylene and at least one vinylidene aromatic comonomer or hindered aliphatic vinylidene comonomer, which interpolymer has an Mn of greater than about 10,000 and comprises from 5 to less than 25 mole percent of the at least one vinylidene aromatic comonomer or hindered aliphatic vinylidene comonomer;    (b) from 5 to 75 weight percent of a substantially random interpolymer of ethylene and at least one vinylidene aromatic comonomer or hindered aliphatic vinylidene comonomer, which interpolymer has an Mn of less than about 8,200 and comprises from 1 to less than 5 mole percent of the at least one vinylidene aromatic comonomer or hindered aliphatic vinylidene comonomer; and    (c) from 5 to 75 weight percent of a substantially random interpolymer of ethylene and at least one vinylidene aromatic comonomer or hindered aliphatic vinylidene comonomer, which interpolymer has an Mn of less than about 8,200 and comprises at least 25 mole percent of the at least one vinylidene aromatic comonomer or hindered aliphatic vinylidene comonomer.    
     
     
         14 . The adhesive of  claim 10 , wherein the substantially random interpolymer is an interpolymer of ethylene, at least one vinylidene aromatic monomer, and optionally at least one α-olefin monomer.  
     
     
         15 . The adhesive of  claim 10 , as applied to a substrate selected from the group consisting of a package, carton, bookbinding, tape, label, decal, bandage, decorative sheet, protective sheet, ceramic tile, vinyl tile, vinyl flooring, carpet backing, nonwoven fabric, woven fabric, personal hygiene device placement strip, sun control film, gasket, caulk, wood, or veneer.  
     
     
         15 . A coextruded or laminated multilayer film, in which at least one layer comprises an adhesive comprising at least one substantially random interpolymer of ethylene and a vinylidene aromatic monomer or a hindered aliphatic vinylidene monomer and optionally at least one C 3 -C 20  α-olefin monomer.  
     
     
         17 . The coextruded or laminated multilayer film of claim  16  in which the adhesive is adhered to a metal foil.  
     
     
         18 . A tape comprising a substrate to which has been applied an adhesive comprising: 
 a. from 40 to 60 weight percent of a substantially random interpolymer of ethylene and a vinylidene aromatic monomer or a hindered vinylidene aromatic monomer and optionally at least one C 3 -C 20  α-olefin monomer, said substantially random interpolymer comprising from 25 to 65 weight percent of the vinylidene aromatic monomer or hindered aliphatic vinylidene monomer,    b. from 40 to 60 weight percent of a tackifier, and    c. from 0 to 10 weight percent of a processing aid,    wherein the adhesive is characterized as having a storage modulus (G′) at 25° C. of from 2×10 5  to 5×10 6  dynes/cm 2  (0.2 to 5 MPa).