MXPA99002107A - Incorporation of free radical inhibitors in polyolefins - Google Patents

Abstract

It has now been found that certain phenolic compounds can be used as free radical inhibitors during polymerization without deactivation of transition metal catalysts. Use of suchcompounds during polymerization is particularly advantageous when they are substantially free of catalyst inactivating compounds such as less substituted phenols and quinones. The invention includes a process for inhibiting deterioration in a polymer by adding a free radical inhibitor during or before polymerization with a transition metal catalyst. It is not necessary to inactivate the free radical inhibitor since it advantageously does not inhibit the transition metal catalyst activity. The process is preferably preceded by a step of purifying the free radical inhibitor to remove compounds which inhibit catalyst activity such as quinones and phenols which are not sufficiently sterically hindered to avoid inhibiting the catalyst. Additionally, the invention includes a composition comprising at least one olefin monomer, a polymer of the monomer, a transition metal catalyst and at least one free radical inhibitor having sufficient substituents to hinder the active inhibiting group such that it does not undesirably inhibit the transition metal catalyst. The invention is particularly useful when the monomer comprises propylene, styrene or a derivative thereof.

Description

INCORPORATION OF FREE RADICAL INHIBITORS IN POLYOLEPHINS This invention relates to the polymerization of olefins, more especially to the polymerization of olefins using transition metal catalysts; The invention also relates to stabilization of polyolefins using especially free radical inhibitors. Transition metal catalysts include Ziegler type catalysts which are well known to those skilled in the art and metallocene catalysts which are also known to those skilled in the art to polymerize olefins. Inhibitors, particularly free radical inhibitors, are often added to the polyolefins after polymerization using said catalysts to prevent or decrease the deterioration caused by free radicals. The addition of the free radical inhibitors has followed the polymerization to avoid the inhibition of the transition metal catalysts. Phenolic compounds are recognized free radical inhibitors but are also thought by those skilled in the art to inhibit transition metal polymerization catalysts. It may also be useful to avoid deterioration induced by free radicals during the polymerization, preferably without substantially inhibiting the transition metal catalysts. The inhibitors added before or during the polymerization could advantageously reduce the deterioration of the polymer by free radicals during the processes that often precede the addition of the inhibitor. Additionally . the addition of the inhibitor during or before the polymerization could advantageously result in a good result and avoid the processing steps such as polymer formed by melting, a step which is now necessary for a good addition of the inhibitor. In some processes the inhibitor is added in solutions and mixing is also necessary as well as the removal of the solvent; both could be advantageously avoided by the addition of the inhibitor before or during the polymerization. In previous attempts to add inhibitors to polymers before or during polymerization, whether the monomeric inhibitors are incorporated into the polymer or not, the active groups of the inhibitors were inactivated, for example by reaction with aluminum reagent, for example, diethylaluminum. See EP 466,263 (Oliver and Young) 1992. Inactivation of the inhibitor is advantageous because the inhibitor is now activated to prevent the deterioration of free radicals and in that the extra steps of the process and reagents are required for the inactivation and removal of the species of inactivation. In addition to the costs associated with extra reagents and extra steps, removal often requires acid (as is the case with inactivators of the aluminum compound) that by itself can be detrimental to a polymer, especially in subsequent uses. It may be convenient to have a method for inhibiting deterioration in a polymer by adding an inhibitor during or before polymerization with a transition metal catalyst without activating the inhibitor or reacting it with one or more substances that reduce its activity with the catalyst. It has now been found that certain phenolic compounds can be used as free radical inhibitors during polymerization without deactivating the transition metal catalysts. The use of said compounds during the polymerization is particularly advantageous when the inhibitors, the resulting mixture with monomer and the catalyst or a combination thereof, are substantially free of compounds that inactivate the catalyst such as less substituted phenols and quinones and when the catalysts Transition metals are activated with compounds that do not react with the inhibitors, especially compounds that do not have aluminum. The invention includes a process to inhibit deterioration in a polymer by mixing an inhibitor with at least one olefin monomer during or before polymerization thereof using a transition metal catalyst. It is not necessary or convenient to inactivate the inhibitor or by reacting it with one or more substances that reduce its activity with the catalyst. The process is preferably preceded by a step of purifying the inhibitor to remove compounds that inhibit catalyst activity such as quinolines and phenols that are not sufficiently sterically hidden and prevent inhibition of the catalyst. Additionally, the invention includes a composition comprising at least one olefin monomer, a polymer of the monomer, a transition metal catalyst and at least one inhibitor having sufficient substituents to hide the active inhibition group, so that no undesirably inhibits the transition metal catalyst. The inhibitor is preferably purified so that the compounds that inhibit the catalyst are substantially removed. Preferably none of the monomers or the catalyst contains said compounds. The invention is particularly useful when the monomer comprises propylene, styrene or a derivative of any of them. The inhibitors useful in the practice of the invention are those which have at least one active group capable of inhibiting free radicals and which have sufficient substitution to hide Each active group in a manner that does not undesirably inhibit a transition metal catalyst. Those skilled in the art recognize that some inhibition of catalyst may be acceptable, however, advantageously, in the practice of the invention only the inhibition of limited catalysts takes place. preferably less than 75 percent, more preferably less than 50 percent, even more preferably less than 25 percent of the catalyst are inhibited by the free radical inhibitors used in the practice of the invention. Those skilled in the art recognize that the amount of inhibition is a function of the molar ratio of inh free radical scavenger to catalyst For example at a ratio of 10000 1, inhibition of 25 to 75 percent is sometimes observed However in the case of a molar ratio of free radical inhibitor to catalyst of 1 1, it is preferably less than a 10 percent reduction in catalyst activity measured by the monomer converted to the polymer per unit of time Each active group in the inhibitor is suitably any active group to inhibit free radicals, preferably a group of active hydrogen XH wherein H is a heteroatom such as oxygen, nitrogen (R "'N where R"' is any hydrocarbyl group or silyl group (such as trimethylsilyl, triethylsilyl, or H3Si)) or sulfur, preferably oxygen, R '"preferably has from 1 to 50 atoms of carbon and optionally from 1 to 5 silicon atoms. More preferably the active group is a hydroxyl group (including phenol), amine, or sulfhydryl, even more preferably a hydroxyl group. Those skilled in the art recognize molecular structures that demonstrate high activity to inhibit free radicals. For example, the active group preferably binds to an aromatic ring, more preferably it is a phenol group. To achieve sufficient steric hindrance to avoid undesirable inhibition of a transition metal catalyst, the inhibitor preferably has at least one concealment group on each carbon adjacent to an active group. The concealing groups are groups large enough to hide the access of a transition metal catalyst to an active inhibition group and advantageously comprise at least 3 carbon atoms, preferably at least 4 carbon atoms. The concealing groups are preferably branched such as isopropyl, tertiary butyl, isobutyl, isopentyl or styryl groups (-CH2-CH2-C6HS). The groups are preferably hydrocarbyl groups or groups substituted with additional active inhibition groups which are also sufficiently sterically hidden to prevent inhibition of a transition metal catalyst, but optionally may have another inert substitution such as ether or trisubstituted amine groups . Inert substitution means substitution which does not undesirably interfere with the action of the active groups or with the polymerization transition metal catalysts. The concealment groups are preferably selected from tertiary butyl groups or styryl groupsoptionally and preferably they are further substituted with at least one additional active inhibition group which in turn is sterically hidden. The preferred styryl group is 1-hydroxy, 2-methylene, 4-methyl, 6-tertiary butyl phenyl, hereinafter referred to as active styryl. The inhibitors preferably have the formula: wherein XH is an active group as previously described; and R is independently a concealment group as previously described; and each R 'is independently hydrogen or any inert substitution, preferably selected from hydrogen, methyl, or R, more preferably selected from hydrogen, methyl, tertiary butyl or styryl, even more preferably wherein the styryl group is an active styryl.

Specific examples include: Linden, when * = binding site Inhibitors are commercially available compounds, known to those skilled in the art or can be prepared by means within the art such as the process reported in Ullmann's Encyclopedia of Industrial Chem., W. Gerhartz ed. , 5th edition, VCH published, pp. 197-199, Vol. A-1, 1985; ibid Vol. A19, pp 3288-340. To avoid undesirable inhibition of the transition metal catalyst, compounds that inhibit the catalyst, particularly, compounds having active groups that are not sterically hidden enough to prevent such inhibition are preferably removed from the inhibitor. That is, while they are not practical for removing each molecule from said compounds, they are sufficiently absent to avoid undesirable inhibition of the transition metal catalyst, preferably the concentration of said compounds is less than 5.0 weight percent, more preferably less than 1.0 percent by weight, even more preferably less than 0.5 percent by weight. Compounds that will be removed include those that have insufficiently occult oxygen containing groups such as hydroxyl groups (including phenol), ketones, aldehydes, aliphatics, alcohols and quinones and even more preferably also include those compounds that inhibit catalysis that have groups of amine. The removal of these compounds is within the experience of the technique through the use of distillation, sublimation, crystallization, division between immiscible solvents, precipitation, chromatography and passage of solutions of the antioxidant through the beds of absorptive solids (such as gel s silica, alumina, clays, zeolites, activated carbon or interlaced polymer beads). The use of absorbent beds is particularly useful for several reasons. Polar impurities in the antioxidant that are more damaging to the metal catalyst are more strongly absorbed and allow the relatively non-polar antioxidant to pass through it. The column is optionally regenerated or replaced when the absorptive capacity has been reached. Another advantage of absorbent beds is that the purification method is often already installed in manufacturing facilities as a means to purify solvents, monomers or a combination thereof. The practice of the invention is applied to polyolefins, ie polymers comprising units derived from olefin monomers (ie monomers containing at least one double bond, hereinafter also Olefin Monomers of Hydrocarbons), preferably alpha olefins and cycloalkanes, more preferably wherein the olefins comprise styrene or propylene or derivative of any of them. The process of the invention can be applied to the polymerization of any olefin monomer or combination thereof. Preferred monomers include alpha-olefins having from 2 to 20,000, preferably from 2 to 20, still more preferably from 2 to 8 carbon atoms and combinations of two or more of said alpha-olefins. Particularly suitable alpha-olefins, include, for example, styrene, alpha-methyl styrene, ethylene, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-ketene , 1 -nonne, 1 -decene, 1 -undecene, 1 -dodecene, 1 -tridecene, 1 -tetradecene, 1 -pentadecene or combinations thereof, as well as oligomeric or polymeric reaction products terminated in long chain vinyl formed during the polymerization and optionally C10-30 olefins specifically added to the reaction mixture in order to produce relatively long chain branches in the resulting polymers. Preferably, the alpha-olefins are styrene or derivatives thereof, ethylene, propene, 1-butene, 4-methyl-1-pentene, 1 -hexene, 1-ketene and combinations of ethylene, propene, with one or more of said other alpha-olefins or a combination thereof. Other preferred monomers include styrene, halo or substituted alkyl, styrenes, tetrafluoroethylene, vinylcyclobutene, 1,4-hexadiene, dicyclopentadiene, ethylidene norbornene and 1,7-octadiene. The mixtures of the monomers mentioned above can also be used. The process of the invention is particularly useful when the monomers comprise styrene or a substituted styrene. It is particularly important to inhibit free radicals in a process of polymerizing styrene using transition metal catalysts especially metallocene catalysts, because such catalysts produce a desirable stereo-regulator, for example a syndiotactic polystyrene, but free radicals produce atactic polystyrene which is preferably avoided in the production of stereo-regular polystyrene. To form stereo-regular polystyrene, styrene is preferably purified to remove oxygen-containing compounds that inhibit catalysis; after styrene it was stored optionally and conveniently. The use of an inhibitor in these early stages may be required to avoid free radical polymerization of the purified styrene known to be particularly susceptible to. free radical polymerization is very advantageous, but is avoided in current practice because the removal of free radical inhibitors which also inhibit or is thought to inhibit transition metal catalysis. Another advantage to adding a free radical inhibitor to styrene before or during the transition metal catalyzed polymerization is to prevent the free radical polymerization of styrene monomer remaining in the stereo-regular polystyrene. Similarly the process of the invention is particularly useful when the monomer comprises propylene because the polypropylene is especially susceptible to the degradation of molecular weight from the action of free radicals. The inhibitor is used in any effective amount to achieve the desired purpose of improved thermal stability (functioning as an antioxidant or a free radical inhibitor). Those skilled in the art recognize that the optimal amount of the inhibitor is a function of the polymer and the conditions to which it will be exposed. The amount is often at least 10 ppm and usually is not more than 50,000 ppm (5 weight percent) advantageously, with a preferred scale of 100 ppm to 5,000 ppm. The process of the invention applies to the use of any transition metal catalyst including Ziegler type catalysts and metallocene type catalysts, both of which are well known to those skilled in the art. For the reasons explained below, the preferred catalysts are activated with compounds that are not reactive with the inhibitors, preferably with catalysts without aluminum. For this reason, metallocene type catalysts are preferred. The practice of the invention is particularly useful with any metallocene transition metal catalyst within the experience of the art. Specific metallocene catalysts known in the art are discussed in such references as EPA Nos. 485,820, 485,821; 485,822; 485,823; 518,092; and 519,237; Patents of E. U.A. Nos. 5, 145,819; 5,296,434, all incorporated herein by reference in their entirety. All references of the present to elements or metals belonging to a certain Group refer to the Periodic Table of the Elements published and entitled by CRC Press, Inc., 1989. Also, any reference to the Group or Groups must be to the Group or Groups as reflected in this Periodic Table of the Elements using the I UPAC system to number groups. Advantageous catalysts for use herein are derivatives of any transition metal including Lanthanides, but preferably Group 3, 4, or Lanthanide metals that are in the formal oxidation state +2, +3 or +4. Preferred compounds include metal complexes comprising from 1 to 3 groups of anionic or neutral ligands attached to p, which are optionally groups of anionic ligands attached to p delocalized, cyclic or non-cyclic. Illustrative of said groups of anionic ligands attached to p are cyclic or non-cyclic, conjugated or non-conjugated dienyl groups and allyl groups. By the term "attached to p" it is meant that the ligand group is attached to the transition metal by means of its delocalized p-electrons. Each atom in the optionally delocalized ap group is independently substituted with a radical selected from the group consisting of hydrogen, halogen, hydrocarbyl, halohydrocarbyl, hydrocarbyl, hydrocarbyl substituted metalloid radicals wherein the metalloid is selected from Group 14 of the Periodic Table the Elements, and said hydrocarbyl or substituted hydrocarbyl metalloid radicals, further substituted with a heteroatom containing portion of Group 1 5 or 16. Within the term "hydrocarbyl" are the branched and cyclic C?. 20 alkyl radicals., aromatic radicals of C6-2o, substituted alkyl aromatic radicals of C7.20 and substituted alkyl aryl radicals of C7.20. In addition, two or more of said adjacent radicals can together form a fused ring system, a hydrogenated fused ring system, or a metallocycle with the metal. Suitable hydrocarbyl substituted organometaloid radicals include mono, di and tri-subtituted organometalloid radicals of Group 14 elements wherein each of the hydrocarbyl groups contains from 1 to 20 carbon atoms. Examples of advantageous hydrocarbyl substituted organometalloid radicals include trimethylsilyl, triethylsilyl, ethyldi methyl si lyl, methylethyl, triethylsilyl, ethyldimethylsilyl, methyldiethylsilyl, triphenylgermyl and trimethylgermyl groups. Examples of portions containing hetero atoms of Group 15 or 16 include portions of amine, phosphine, ether or portions of thioether or monovalent derivatives of the same, v. gr. , amide, phosphine, ether or thioether groups attached to the transition metal or Lanthanide metal, and attached to the hydrocarbyl group or the hydrocarbyl substituted metalloid-containing group.

Examples of anionic delocalized ap include cyclopentadienyl, indenyl, fluoroenyl, tetrahydroindenyl, tetrahydrofluoroenyl, octahydrofluoroenyl, pentadienyl, cyclohexadienyl, dihydroanthracenyl, hexahydroanthracenyl and decahydroanthracenyl groups, as well as substituted silyl derivatives substituted with C?. 10 hydrocarbyl or substituted with hydrocarbyl C1.10. Preferred anionic delocalized linked groups are cyclopentadienyl, pentamethylcyclopentadienyl, tetramethylcyclopentadienyl, tetramethylsilylcyclopentadienyl, indenyl, 2,3-dimethylindenium, fluoroenyl, 2-methylindenyl, 2-methyl-4-phenylindenyl, tetrahydrofluoroenyl, octahydrofluoroenyl and tetrahydroindenyl. A preferred class of catalysts are the transition metal complexes corresponding to Formula A: L £ MXmX'nX "p, or a dimer thereof wherein: L is an attached anionic delocalized group appended to M, containing up to 50 non-hydrogen atoms, optionally two L groups can be joined forming a bridged structure and further optionally an L is attached to X; M is a Group 4 metal of the Periodic Table of the elements in the formal oxidation state of +2, +3 or +4; X is an optional divalent substituent of up to 50 non-hydrogen atoms and together with L forms a metallocycle with M; X 'in each presentation in an optional neutral Lewis base having up to 20 non-hydrogen atoms and optionally an X' and an L can be joined together; X "each time it is presented is an anionic monovalent moiety having up to 40 non-hydrogen atoms, optionally, two X groups" are covalently bonded to form a divalent dianionic moiety having two valencies attached to M, or optionally two X groups " they are covalently linked to form a neutral, conjugated or non-conjugated diene which is p-attached to M (where M is the oxidation state +2) or optionally one or more of the X "groups and one or more of the X groups 'are joined thereby forming a portion that is covalently bound to M and coordinated thereto by means of a Lewis base functionality; e is 0, 1 or 2; m is 0 or 1; n is a number from 0 to 3; p is an integer from 0 to 3; and the sum of / + m + p, is equal to the formal oxidation state of M, except when 2 groups X "form a conjugated or neutral non-conjugated diene that is p attached to M, in which case the sum of C + m is equal to the oxidation state M Preferred complexes include those containing one or two L groups. The latter complexes include those containing a bridge group linking the two L groups. The preferred bridge groups those corresponding to the formula (ER * 2) X where E is silicon, germanium, tin or carbon, R * independently of each occur is hydrogen or a selected group of silyl, hydrocarbyl, hydrocarbyloxy and combinations thereof, said R * having up to 30 atoms of carbon or silicon, and x is 1 to 8, preferably R * independently of each occurrence is methyl, ethyl, propyl, benzyl, tert-butyl, phenyl, methoxy, ethoxy or phenoxy. Examples of the complexes containing the two groups L are the compounds q ue correspond to the formula wherein M is titanium, zirconium or hafnium, preferably zirconium or hafnium, in the oxidation state form +2 or +4. R3 each time it is presented is independently selected from the group consisting of hydrogen, hydrocarbyl, silyl, germyl, cyano, halo, and combinations thereof, R3 having up to 20 non-hydrogen atoms, or adjacent R3 groups together forming a derivative divalent (for example, a hydrocarbyl-ilo group, germadi-yl) thus forming a fused ring system, and X "independently of each occurrence is a group of anionic ligands of up to 40 non-hydrogen atoms, or two groups X "together form a divalent anionic ligand group of up to 40 atoms that are not hydrogen or together are a conjugated diene having from 4 to 30 non-hydrogen atoms forming a complex with M, wherein M is in the oxidation state formal +2, and R *, E, and x are as previously defined A further example of a preferred class of coordination complexes useful in the practice of the present invention corresponds to the Formula AIV: R 'R' where. M is titanium, zirconium or hafnium, in the formal oxidation state +2, + 3 or +4; And independently whenever it is presented is carbon or silicon; R * independently each time it is presented is selected from the group consisting of C? .β hydrocarbyl and C? .β hydrocarbyloxy, with the proviso that at least once R * occurs, it is C hydrocarbyloxy? .6; m is 1 or 2; R 'independently each time it is presented is selected from the group consisting of hydrogen, hydrocarbyl, silyl, germyl, cyano, halo and combinations thereof, the R' having up to 20 non-hydrogen atoms or adjacent R 'groups formed together a divalent derivative which is a hydrocarbaryl-yl, siladi-yl or germadi-yl group; X 'is a conjugated diene having from 4 to 30 non-hydrogen atoms, which form a complex p with M when M is in the formal oxidation state +2, whereby n is 1 and p is 0; X "each time it is presented is an anionic ligand group that is covalently bound to M when M is in the formal oxidation state +3 or +4, so n is 0 and p is 1 or 2 and optionally two X groups "together for a group of divalent anionic ligands. The above metal complexes are especially suitable for the preparation of polymers having a stereo-regular molecular structure. In said capacity it is preferred that the complex have a Cs symmetry or have a stereo-rigid chiral structure. Examples of the first type are compounds having different systems attached to delocalized p, such as a cyclopentadienyl group and a fluoroenyl group. Similar systems based on Ti (IV) or Zr (IV) were described for the preparation of syndiotactic olefin polymers in Ewen, et al., J. Am. Chem. Soc. 1 10, 6255-6256 (1980). Examples of chiral structures include bis-indenyl complexes rae. Similar systems based on Ti (IV) or Zr (IV) were described for the preparation of sotactic olefin polymers in Wild et al., J. Organomet. Chem. 232, 233-47, (1982). The bridged ligands containing two illustrative groups attached to p are: (dimethylsilyl-bis (cyclopentadienyl)), (dimethylsilyl-bis (methylcyclopentadienyl)), (dimethylsilyl-bis (ethylcyclopentadienyl)), (Dimethylsilyl-bis (t-butylcyclopentadienyl)), (dimethylsilyl-bis (tetramethylcyclopentadienyl)), (dimethylsilyl-bis (indenyl)), (dimethylsilyl-bis (tetrahydroindenyl)), (dimethylsilyl-bis (fluoroenyl)), (dimethylsilyl bis (tetrahydrofluoroenyl)), (dimethylsilyl-bis (2-methyl-4-phenylindenyl)), (Dimethylsilyl-bis (2-methylindenyl)), (dimethylsilyl-cyclopentadienyl-fluoroenyl), (dimethylsilyl-cyclopentadienyl-octahídrofluoroenilo), (dimethylsilyl-cyclopentadienyl-tetrahidrofluoroenilo), (1, 1, 2, 2-tetramethyl-1, 2- disilyl-bis-cyclopentadienyl), (1, 2-bis (cyclopentadienyl) ethane, and (isopropylidene-cyclopentadienyl-fluoroenyl). the "preferred X groups are selected from hydride groups hydrocarbyl, silyl, germyl, halohydrocarbyl, halosilyl, silylhydrocarbyl and aminohydrocarbyl, or two X groups "together form a divalent derivative of a conjugated diene or also form a conjugated diene attached to neutral C. The most preferred groups X '" are hydrocarbyl groups of C1 -2o, including those optionally formed of two X groups " A further class of metal complexes used in the present invention corresponds to the preceding formula L, MXmX'nX "p, or a dimer thereof, wherein X is a divalent substituent of up to 50 non-hydroxy atoms. which together with L form a metallocycle with M. Preferred divalent X substituents include groups containing up to 30 non-hydrogen atoms comprising at least one atom which is oxygen, sulfur, boron or a member of Group 14 of the Periodic Table of the Elements directly attached to the group attached to delocalized ap and a different atom, selected from the group consisting of nitrogen, phosphorus, oxygen and sulfur that is covalently bound to M. A more preferred class the metal coordination complexes of Group 4 used according to the present invention corresponds to the formula: where M is titanium, zirconium, or hafnium in the formal oxidation state +2, + 3 or +4. X "and R3 are as previously defined for the formulas Al and Al 1; Y is -O-, -S-, -NR * -, -NR * 2- or -PR * -; and Z is SiR * 2, CR * 2, SiR * 2SiR * 2) CR * 2CR * 2, CR * = CR *. CR * 2SiR * 2 or GeR * 2, where R * is as previously defined. Illustrative Group 4 metal complexes which may be employed in the practice of the present invention include: cyclopentadienyltitaniotrimethyl, cyclopentadienyltitaniotriethyl, cyclopentadienyltitaniotrisopropyl, cyclopentadieni Ititaniotrif in ilo, cyclopentadienyltitaniotribenzyl, cyclopentadienyltitanium-2,4-dimethylpentadienyl, cyclopentadienyltitanium-2,4-dimethylpentadienyltriethylphosphine, cyclopentadienyltitanium-2,4-dimetilpentadieniltrimetilfosfina methoxide ciclopentadieniltitaniodimetilo of ciclopentadíeniltitaniodimetilo chloride, pentametilciclopentadieniltitaniotrimetilo, indeniltitaniotrimetilo, indeniltitaniotrietilo, indeniltitaniotripropilo, indeniltitaniotrifenilo, tetrahydroinden i Ititaniotri benzyl, pentametilci Clo pentad ieni Ititaniotri isopropyl, pen or pen ta meti icicl tad ieni Ititaniotriben cilo methoxide of pentamethylcyclopentadienyltitaniodimethyl, pentamethylcyclopentadienyltitaniodimethyl chloride, bis (? 5-2,4-dimethylpentadienyl) tit anion, bis (? 5-2, 4-dimethylpentadienyl) titanotrimethylphosphine, bis (? 5-2,4-dimethylpentadienyl) titanothriethylphosphine, octahydrofluoroethyltitanitrimethyl, tetrahydroindenyltitaniotrimethyl, tetrahydrofluoroethyltitaniotrimethyl, (tert-butylamido) (1,1-dimethyl-2,3, 4-9, 10-1, 4,? 5,6,7,8-hexahydronaphthalenyl) dimethylsilaneditaniodimethyl, (tert-butylamido) (1, 1, 2, 3-tetramethyl-2, 3, 4, 9, 10-1 , 4,5, 6,7,8-hexahydronaphthalenyl) dimethylsilanetitanium dimethyl, (tert-butylamido) (tetramethyl-? 5-cyclopentadienyl) dimethylsilanetitanium dibenzyl, (tert-butylamido) (tetramethyl-? 5-cyclopentadienyl) dimethylsilanetitanium dimethyl, (tert-butylamido) (tetramethyl-? 5-cyclopentadienyl) -1,2-ethanediylititanium dimethyl, (tert-butylamido) (tetramethyl-? 5-indenyl) dimethylsilanetitanium dimethyl, (tert-butylamido) (tetramethyl-? 5- cyclopentadienyl) dimethylsilane titanium (11) 2- (dimethylamino) benzyl; (tert-butylamido) (tetramethyl-? 5-cyclopentadienyl) dimethylsilanetitanium (11) allyl; (tert-butlamido) (tetramethyl-? 5-cyclopentadienyl) dimethylsilanetitanium (I I I) 2,4-dimethylpentadienyl; (tert-butylamido) (tetramethyl-? 5-cyclopentadienyl) dimethyl-silanetitanium (I I) 1,4-diphenyl-1,3-butadiene; (tert-butylamido) (tetramthyl-? 5-cyclopentadienyl) dimethyl-silanetitanium (I I) 1, 3-pentadiene; (tert-butylamido) (2-methylindenyl) dimethylsilanetitanium (I I) 1,4-diphenyl-1,3-butadiene; (tert-butylamido) (2-methylindenyl) dimethylsilanetetanium (I I) 2,4-hexadiene; (tert-butalamido) (2-methylindenyl) dimethylsilanetitanium (IV) 2, 3-dimethyl-1,3-butadiene; (tert-butlamido) (2-methylindenyl) dimethylsilanetitanium (IV) isoprene; (tert-butylamido) (2-methylindenyl) dimethylsilanetitanium 1,3-butadiene (IV) 2,3-dimethyl-1,3-butadiene; (tert-butylamido) (2,3-dimethylindenyl) dimethylsilanetitanium (IV) isoprene; (tert-butylamido) (2,3-dimethylindenyl) dimethylsilanetitanium (IV) dimethyl; (tert-butylamido (2,3-dimethylindenyl) dimethylsilanetitanium (IV) dibenzyl; (tert-butylamido (2,3-dimethylindenyl) dimethylsilanetitanium 1,3-butadiene; (tert-butylamido) (2,3-dimethylindenyl) dimethylsilanetitanium (II 1, 3-pentadiene; (tert-butylamido) (2,3-dimethylindenyl) dimethylsilanetitanium (II) 1,4-diphenyl-1,3-butadiene; (tert-butylamido) (2-methylindenyl) dimethylsilanetitanium (II) 1 , 3-pentadiene; (tert-butylamido) (2-methylindenyl) dimethylsilanetitanium (IV) dimethyl; (tert-butylamido) (2-methylindenyl) dimethylsilanetitanium (IV) dibenzyl; (tert-butylamido) (2-methyl-4-phenylindenyl) dimethylsilanetitanium (II) 1,4-diphenyl-1,3-butadiene, (tert-butylamido) (2-methyl-4-phenylindenyl) dimethylsilanetitanium (II) 1,3-pentadiene, (tert-butylamido) (2-methyl) -4-phenylindenyl) dimethylsilanetitanium (II) 2,4-hexadiene, (tert-butylamido) (tetramethyl-? 5-cyclopentadienyl) dimethyl-silanetitanium 1,3-butadiene, (tert-butylamido (tetramethyl-? 5-cyclopentadienyl) dimethyl-silanetitanium (IV) 2,3-dimethyl-1, 3 -butadiene, (tert-butylamido) (tetramethyl-? 5-cyclopentadienyl) dimethyl-silanetitanium (IV) isoprene, (tert-butylamido (tetramethyl-? 5-cyclopentadienyl) dimethyl-silanetitanium (II) 1,4-dibenzyl-1, 3-butadiene, (tert-butylamido) (tetramethyl-? 5- cyclopentadienyl) dimethylsilanetitanium (II) 2,4-hexadiene, (tert-butylamido) (tetramethyl-? 5-cyclopentadienyl) dimethyl-silanetitanium (II) 3- methi 1-1, 3- pentadiene, (tert-butylamido) (2,4-dimethylpentadiene-3-yl) dimethyl-silanetitaniodimethyl, (tert-butylamido) (6,6-dimethylcyclohexadienyl) dimethyl-silanetitaniodimethyl, (tert-butylamido) (1,1-dimethyl-2, 3, 4, 9, 10- 1, 4, 5,6,8-hexahydronaphthalen-4-yl) dimethylsilanetitanium dimethyl, (tert-butylamido) (1,1, 2,3-tetramethyl) -2,3,4,9, 10-1, 4,5,6,7,8-hexahydronaphthalen-4-yl) dimethylsilaneditaniodimethyl, (tert-butylamido ) (tetramethyl-? 5-cyclopentadienyl methylphenyl-silanetitanium (IV) dimethyl, (tert-butylamido) (tetramethyl-? 5-cyclopentadienyl methylphenylsilanetitanium (IV) dimethyl, (tert-butylamido) (tetramethyl-? 5-cyclopentadienil) methylphenyl-silanetitanium (II) 1, 4-diphenyl-1,3-butadiene, 1- (tert-butylamido) -2- (tetramethyl-? 5-cyclopentadienyl) ethanediyl-titanium (IV) dimethyl and 1- (tert-butylamido) -2- (tetramethyl) -? 5-cyclopentadienyl) ethanodii I-titanium (II) 1,4-dif eni 1-1, 3-butadiene. Complexes containing two L groups that include bridged complexes suitable for use in the present invention include: bis (cyclopentadienyl) cycrylonitrile bis (cyclopentadienyl) zirconium dibenzyl, bis (cyclopentadienyl) zirconium methyl benzyl, bis (cyclopentadienyl) zirconium methyl phenyl, bis ( cyclopentadienyl) zirconiodiphenyl, bis (cyclopentadienyl) titanium-allyl, bis (cyclopentadienyl) zirconiomethyl methoxide, bis (cyclopentadienyl) zirconiomethyl chloride, bis (pentamethylcyclopentadienyl) zirconium imethyl, bis (pentamethylcyclopentadienyl) titanium dimethyl, bis (indenyl) zirconiodimethyl, indenylfluoroenylcirconiodimethyl, bis (indenyl) circoniometil (2- (dimethylamino) benzyl), bis (indenyl) zirconium methyltrimethylsilyl, bis (tetrahydroindenyl) zirconium methyltrimethylsilyl, bis (pentamethylcyclopentadienyl) circoniometilbencilo, bis (pentamethylcyclopentadienyl) circoniodíbencilo methoxide, bis (pentamethylcyclopentadienyl) circoniometilo chloride bis (pentamethylcyclopentadienyl) zirconium omethyl, bis (methylethylcyclopentadienyl) zirconiodimethyl, bis (butylcyclopentadienyl) zirconium dibenzyl, bis (t-butylcyclopentadienyl) zirconiodimethyl, bis (butylcyclopentadienyl) zirconium dibenzyl, bis (t-butylcyclopentadienyl) zircon iodimethyl, bis (ethyltetramethylcyclopentadienyl) zirconodimethyl, bis (methylpropylcyclopentadienyl) zirconium dibenzyl, bis (trimethylsilylcyclopentadienyl) zirconium dibenzyl, dimethylsilyl-bis (cyclopentadienyl) zirconiomethyl, dimethylsilyl-bis (tetramethylcyclopentadienyl) titanium- (III) allyl, dimethylsilyl-bis (t-butylcyclopentadienyl) zirconium dichloride, dimethylsilyl-bis (n- butylcyclopentadienyl) zirconium dichloride, (methylene-bis (tetramethylcyclopentadienyl) titanium (III) 2- (dimethylamino) benzyl, (methylene-bis (n-butylcyclopentadienyl) titanium (III) 2- (dimethylamido) benzyl, dimethylsilyl-bis (indenyl) -circonium-benzylchloride , dimethylsilyl-bis (2-methylindenyl) zirconiodimethyl, dimethylsilyl-bis (2-methyl-4-phenylindenyl) zirconiodimethyl, dimethylsilyl-bis (2-methylindenyl) zircon io (II) -1,4-diphenyl-1,3-butadiene, d -methylsilyl-bis (2-methyl-4-phenylindenyl) zirconium (II) 1,4-diphenyl-1,3-butadiene, dimethylsilyl-bis (tetrahydroindenyl) zirconium (II) 1,4-diflu enyl-1,3-butadiene, dimethylsilyl-bis (fluoroenyl) zirconiomethylchloride, dimethylsilyl-bis (tetrahydrofluoroenyl) zirconium bis (trimethylsilyl), (isopropylidene) (cyclopentadienyl) (fluoroenyl) zirconium-benzyl , and dimethylsilyl (tetramethylcyclopentadienyl) (fluoroenyl) zirconium dimethyl. Other catalysts, especially catalysts containing other metals in Group 4, of course, will be apparent to those skilled in the art. Preferred metallocene species for use in the practice of the present invention include complexes of restricted geometry metals, including titanium complexes and methods for their preparation as described in United States Application Serial No. 545,403, filed July 3. 1990 (EP-A-416,815); Application of E. U.A. Series No. 967,365, filed on October 28, 1992 (EP-A-514,828); and Application of E. U.A. Series No. 876,268, filed on May 10, 1992, (EP-A-520, 732), as well as US-A-5,055,438, US-A-4,057-475, US-A-5,096,867, US-A-5,064 , 802, US-A-5,096,867, US-A-5, 132,380, US-A-5, 1 32, 380, US-A-5,470, 993, US-A-5, 486,632 and US-A-5, 1 32,380, US-A-5, 321, 106. The teachings of all prior patents, publications and patent applications are hereby incorporated by reference in their entirety. Metallocene catalysts advantageously become catalytically active by combination with one or more activating cocatalysts, by the use of an activation technique or a combination thereof. In the practice of the present invention, advantageous catalysts are those that do not react with the inhibitors, preferably those that do not contain aluminum, especially boron-containing cocatalysts within the skill of the art. Among the boron-containing cocatalysts are the tri (hydrocarbyl) boron compounds and halogenated derivatives thereof, advantageously having from 1 to 10 carbon atoms in each hydrocarbyl or halogenated hydrocarbyl group, more especially perfluorinated tri (aryl) boron compounds, and more especially tris (pentafluorophenyl) borane); amine, phosphine, aliphatic alcohol and mercaptan adducts of halogenated tri (hydrocarbyl C? .-? 0) boron compounds, especially said adducts of perfluorinated tri (aryl) boron compounds. Alternatively, the cocatalyst includes borates such as tetraphenyl borate which have as counterions ammonium ions such that they are within the skill of the art as illustrated by European Patent EP 672,688 (Canich, Exxon), published on September 20, 1995. Aluminum compounds, especially cocatalysts, are preferably avoided since they react with inhibitors used in the practice of the invention. Said reaction reduces the effectiveness of the inhibitor and requires the removal of the aluminum compound from the inhibitor to activate the inhibitor. Strong acids are of a type of compound used in the removal of aluminum, but effective contact with strong acids often involves function or dissolution of the product and then removal of the solvent or cooling and grinding of the resulting polymer. In the practice of the present invention, the cocatalysts are used in amounts and under conditions within the skill of the art. Its use is applied to all processes within the experience of the technique, including processed polymerization of the solution, slurry, bulkiness (especially propylene) and gas phase. Said processes include those completely described in the references cited previously. The molar ratio of catalyst / cocatalyst or activator employed preferably ranges from 1: 10,000 to 100: 1, more preferably from 1: 5000 to 10: 1, more preferably from 1: 1000 to 1: 1. The molar ratio of the inhibitor to catalyst is preferably at least 50. More preferably, the molar ratio of the inhibitor to catalyst is preferably at least 100. When certain catalysts are used to polymerize higher α-olefins, especially propylene, it can be it is also convenient to contact the catalyst / cocatalyst mixture with a small amount of ethylene or hydrogen (preferably at least one mole of ethylene or hydrogen per mole of metal complex, suitably from 1 to 100,000 moles of ethylene or hydrogen per mole of metal complex ). This contact may occur before, after or simultaneously with contact with the higher α-olefin. If the above Lewis acid activated catalyst compositions are not treated in the manner mentioned, extremely long induction periods are found or there is no polymerization result. The ethylene or hydrogen can be used in a suitably small amount so that no significant effect on the properties of the polymer is observed. In most cases, the polymerization advantageously takes place at conditions known in the prior art for polymerization reactions of the Ziegler-Natta or Kaminsky-Sinn type, that is, at temperatures of 0-250 ° C and pressures from atmospheric to 3000 atmospheres Optionally, the suspension, solution, slurry, gas phase or high pressure are used in batch or continuous or other process conditions, including recycling of condensed monomers or solvent. Examples of such processes are well known in the art, for example, WO 88/02009-AI or Patent of E. U.A. No. 5,084,534, describe conditions that are advantageously employed with the polymerization catalysts and are incorporated herein by reference in their entirety. A support, especially of silica, alumina or a polymer (especially polytetrafluoroethylene or a polyolefin) is optionally employed and conveniently used when the catalysts are used in a gas phase polymerization process. Such supported catalysts are advantageously not affected by the presence of liquid aliphatic or aromatic hydrocarbons such as are optionally present under the use of condensation techniques in a gas phase polymerization process. The methods for the preparation of supported catalysts are described in numerous references, examples of which are US Patents .A. Nos. 4,808,561, 4,912,075, 5,008,228, 4,914,253, and 5,086,025 and are suitable for the preparation of supported catalysts. In said process the reagents and catalysts are added to the solvent sequentially, in any order, or alternatively one or more of the reactants or components of the catalyst system are premixed with solvent or material preferably miscible therewith, then mixed together or in more solvent optionally containing the other reagents or catalysts. Preferred process parameters depend on the monomers used and the desired polymer. The polymerization of oiefins is within the experience of the technique. When ethylene is used as a monomer, ethylene is preferably advantageously added to the reaction vessel in an amount to maintain a differential pressure in excess of the combined vapor pressure of solvent, inhibitor and optionally alpha-olefin. Generally, the polymerization process is carried out with an ethylene differential pressure of 70 to 7000 kPa, more preferably 280 to 2800 kPa. The polymerization is then carried out generally at a temperature of 25 to 200 ° C, preferably 50 to 170 ° C and even more preferably 70 to 140 ° C. When the propylene or styrene is a monomer, it is added to the reaction vessel in predetermined amounts to achieve predetermined monomer ratios, optionally in gaseous form using a bonded mass flow controller. Alternatively propylene or liquid monomers are added to the reaction vessel in predetermined amounts to result in desired ratios in the final product. They can be added together with the solvent (if any), alpha-olefin and functional comonomer, or alternatively added separately. The pressure in the reactor is a function of the temperature of the reaction mixture and the relative amounts of propylene, other monomers or a combination thereof used in the reaction. Advantageously, the polymerization process was carried out at a pressure of 70 to 7000 kPa, more preferably 980 to 1200 kPa. The polymerization is then carried out at a temperature of 25 to 200 ° C, preferably 50 to 100 ° C and even more preferably 60 to 80 ° C. The process is advantageously continuous, in which case the reagents are added continuously or at intervals and the catalyst and, optionally the cocatalyst, are added as necessary to maintain the reaction. While one advantage of the process of the invention is to avoid aluminum compounds that protect or in some way react with the inhibitors, for example in a molar ratio of 1: 1, those skilled in the art will recognize that aluminum compounds can still be used. advantageously in very small amounts for example to remove (sweep) water. Therefore, while the compositions of the invention preferably avoid aluminum in amounts that reach a molar ratio of 1: 1 with the inhibitors, the aluminum compounds are optionally present in incidental amounts, for example in amounts corresponding to a molar ratio of inhibitor to aluminum compound greater than 50.1, more preferably greater than 100: 1. Advantageously, because most of the incidental amounts of aluminum are used in the process of the invention, the resulting polymers of the invention have little residual aluminum, less than similar polymers produced by processes within the experience of the subject. Additionally, because acid treatment is not needed to remove aluminum, there are still no harmful effects such as degradation of the residual acid, or a combination thereof of said treatment. The compositions containing the inhibitors, transition metal catalysts and monomers described above are novel, particularly when the aluminum compounds are present in the stated incidental amounts. In the prior art, inhibitors are avoided in the presence of the catalysts because they are thought to inhibit catalysis. Alternatively, precursors of the inhibitors, for example inhibitors reacted with a deactivation composition, for example aluminum compounds, were present in place of the inhibitors themselves. The presence of boron-containing catalysts or activating compounds is still more novel since it emphasizes a situation in which aluminum compounds that can incidentally protect the inhibitor are not necessary and are preferably avoided.

The following examples to illustrate this invention and not to limit it. The ratios, parts and percentages are by weight unless stated otherwise. Examples (Ex) of the invention are designated numerically while comparative samples (MC) are designated alphabetically and are not examples of the invention. For proton NMRs, 5 mm tubes of a polymer sample were analyzed in CI2CDCDCI2 solutions (about 5 weight percent / weight) at a probe temperature at 130 ° C. Proton NMR was useful to determine the incorporation of phenolic monomers. The peaks at 7 0 ppm (smglete for aromatic protons) and at 2 5 ppm (doublet for benzylic methylenes) were present. The last assignment was confirmed using alylbenzene as a comonomer. Gel permeation chromatography (CPG) was carried out using a column of interlaced polystyrene gel chromatography commercially available from Polymer Laboratories under the trade designation of mixed column D PLgel (inner diameter 10 mm by 300 mg long) filled with 5 μm particles A set detector of diode disposition at 280 nm (broadband 4nm) was used in series with a HP 1057 refractive index detector commercially available from Hewlett Packard according to manufacturer directions Polymers were dissolved in chloroform (1 weight percent / volume) except when noted Flow rate was set at 0 5 mL / rnin, with an injection volume of 25 μL The column was calibrated using a normal pohestire not large (Mw 250,000, Mn 100,000) with the diode array detector assembly at 254 nm Example 1: Preparation and Use of the Free Radical Inhibitor During Polymerization. A sample of 10.6 g of orange 2,6-di-tert-butylphenol from Aldrich was dissolved in 8 mL of isooctane and injected onto a 400 g silica gel column using a commercially available low pressure chromatography apparatus Biotage. The eluent was 2 percent toluene / hexane, and fractions of 1000 mL were taken and analyzed by gas chromatography. Almost all of the phenol was eluted in the second and third fractions, which were combined and evaporated to give 8.5 of the viscosity oil without color. Analysis of the raw raw material and the fractions purified by gas chromatography resulted in the following analysis ("nd" indicates that the peak was not detected with an estimated detection limit of 0.05 percent).

The peak at 3.35 minutes was identified as 2-tert-butylphenol, and the peak at 4.80 minutes was 2,6-di-tert-butylphenol. The other components were unknown, but they are suspected to be di-tert-butylphenol isomers. The analysis was carried out using the following conditions: column DB-5, DI 0.53 mm, (internal diameter) film thickness 3 μm, length 15 m, top helium pressure (21 kPa), column injection in cold, flame ionization detector, HP5890 gas chromatograph, oven temperatures started at 200 ° C, maintained for 1 minute, then raised to 10 ° C / minutes at 270 ° C, and finally maintained for 5 minutes. Polymerization Reaction A two liter autoclave reactor was charged with 636 grams of Isopar-E ™ mixed alkane solvent (commercially available from Exxon Chemicals Inc.) and 150 g of propylene. Hydrogen was added as a molecular weight control agent by differential pressure expansion of a 75 mL addition tank at 1772 kPa. The reactor was heated to 70 ° C and 5 mL of 2,6-di-tert-butylphenol (purified above, a combination of fractions 2 and 3) together with 15 micromoles each of dimethyl ethylidene-bis (indenyl) catalyst were added. ) zirconium and cocatalyst (B (C6FS) 3) (both 0.005 M in toluene) that were premixed in the drying box. This solution was transferred to a catalyst addition tank and injected into the reactor. Three additional micromoles of each of the catalyst and cocatalyst were added to the reactor at 35 minutes in operation. The polymerization conditions were maintained for 44 minutes. The resulting solution was removed from the reactor and dried in a vacuum oven at a maximum temperature of 140 ° C for 1 5 hours to give 87.9 g of crystalline polymer.

Claims (10)

1. CLAIMS 1. A process for inhibiting deterioration in a polymer comprising mixing an inhibitor of formula 1: wherein XH is an active hydrogen group with X as an oxygen, nitrogen or sulfur; each R is independently an aryl or alkyl concealment group having enough atoms to form a sterically hidden XH group, sufficiently hidden to prevent reaction of XH with the transition metal catalyst so that less than 50 percent of the catalyst is inhibited by the inhibitor; and each R 'is independently hydrogen or any inert substitution which does not undesirably interfere with the action of the active group or with the polymerization transition metal catalyst; with at least one olefin monomer, during or before polymerization thereof using a metallocene catalyst having a transition metal of Group 3, Group 4 or Lanthanide in the formal oxidation state +2, +3, or + 4 wherein the molar ratio of inhibitor for any aluminum compounds present in at least 100: 1.
2. 2. The process of claim 1, wherein the inhibitor is added to the monomers before contacting the same with the catalyst.
3. 3. The process of claim 1, wherein the inhibitor is added to the catalyst before contacting it with the monomer.
4. 4. The process of claim 1, wherein the inhibitor is added during contact with the catalyst and the monomers. The process of any of claims 1-4, wherein X is oxygen, sulfur or nitrogen, each R is independently t-butyl or isobutyl, isopropyl, isopentyl or an unsubstituted styryl group or 1-hydroxy, 2-methylene , 4-methyl, butyl phenyl 6-tertiary. 6. The process of any of claims 1-5, wherein the inhibitor is 2,6-di-t-butylphenol. The process of any of claims 1-6, wherein the monomer is selected from ethylene, 1-hexen, 1-ketene, propylene, styrene and mixtures thereof. The process of any of claims 1-7, wherein the transition metal catalyst is (5 5-C3Me) SiMe2 (N-tBu) TiMe2; of the formula L £ MXmX'nX "P, or a dimer thereof wherein L is an attached anionic p-linked group that binds to M, containing up to 50 non-hydrogen atoms, optionally two L groups can be joined forming one bridged structure and optionally an L is joined to X, M is a metal of Group 4 of the Periodic Table of the elements in the formal oxidation state +2, +3 or +4; X is an optional divalent substituent of up to 50 nonhydrogen atoms that together with L and forms a metallocycle with M. X 'in each presentation in a neutral Lewis base optionally having up to 20 atoms other than hydrogen and optionally one X' and an L can join together; X "each time it occurs is a monovalent portion anion having up to 40 atoms other than hydrogen, optionally, two X" groups are covalently linked to form a dianionic portion divalent having two valences bound to M, or optionally two X " they are covalently linked to form a neutral, conjugated or non-conjugated diene which is p-attached to M (where M is the oxidation state +2) or optionally one or more of the X "groups and one or more of the X groups 'are joined thereby forming a portion that is covalently bound to M and coordinated thereto by means of a Lewis base functionality; t is 0, 1 or 2; m is 0 or 1; n is a number from 0 to 3; p is an integer from 0 to 3; and the sum of i + m + p, is equal to the formal oxidation state of M, except when 2 groups X "form a conjugated or neutral non-conjugated diene that is p attached to M, in which case the sum of i + m is equal to the oxidation state M: or Formula Al l í R ' wherein: M is titanium, zirconium or hafnium, in the formal oxidation state +2, +3 or +4; And it is -O-, -S-, -NR * -, -NR * 2- or -PR * -; and Z is SiR * 2, CR * 2, SiR * 2SiR * 2, CR * 2CR * 2, CR * = CR *, CR * 2SiR * 2 or GeR * 2, where R * is as previously defi R 'independently each time it is presented is selected from the group consisting of hydrogen, hydrocarbyl, silyl, germyl, cyano, halo and combinations thereof, the R' having up to 20 non-hydrogen atoms or adjacent R 'groups together form a divalent derivative which is a hydrocarbaryl-yl, siladi-yl or germadi-yl group; X 'is a conjugated diene having from 4 to 30 non-hydrogen atoms, which form a p complex with M when M is in the formal oxidation state +2, whereby n is 1 and p is 0; X "each time it is presented is an anionic ligand group that is covalently bound to M when M is in the formal oxidation state +3 or +4, so n is 0 and p is 1 or 2 and optionally two X groups "together for a group of divalent ammonium ligands, wherein n is O; or a dimer, solvated adduct, chelated derivative or mixture thereof, or Formula Al or Al l: Where M is titanium, zirconium or hafnium, preferably zirconium or hafnium in the formal oxidation state +2 or +4 R3 each time it occurs it is independently selected from the group consisting of hydrogen, hydrocarbyl, silyl, germyl, cyano, halo and combinations thereof, R3 having up to 20 non-hydrogen atoms, or adjacent R3 groups together form a divalent derivative (eg, a hydrocarbyl-yl group, germadi-yl) thus forming a fused ring system, and X "each time it is presented is an anionic ligand group of up to 40 atoms that are hydrogen, two X groups" together form a divalent anionic ligand group of up to 40 non-hydrogen atoms or together they are a conjugated diene having 4 to 30 atoms that are not hydrogen forming a complex with M, so that M is in the formal oxidation state, and R * independently each time it is hydrogen or a selected group of silyl, hydrocarbyl, hyd rocarbyloxy and combinations thereof, said R * having up to 30 carbon or silicon atoms and x is 1 to 8; or Formula AIV X "independently of each occurrence is a group of anionic ligands of up to 40 non-hydrogen atoms, or two X groups" together form a divalent anionic ligand group of up to 40 non-hydrogen atoms or together they are a conjugated diene having from 4 to 30 atoms that are not hydrogen forming a complex with M, where M is in the formal oxidation state +2, and R *, E, and x are as previously defined A further example of a class Preferred of the coordination complexes useful in the practice of the present invention corresponds to the Formula AIV: R 'R " where: M is titanium, zirconium or hafnium, in the formal oxidation state +2, + 3 or +4; And independently whenever it is presented is carbon or silicon; R * independently each time it is presented is selected from the group consisting of hydrocarbyl of C? -6 and hydrocarbyloxy of C? .6, with the proviso that at least once R * occurs, it is hydrocarbyloxy of C? -6; m is 1 or 2; R 'independently each time it is presented is selected from the group consisting of hydrogen, hydrocarbyl, silyl, germyl, cyano, halo and combinations thereof, the R' having up to 20 non-hydrogen atoms or adjacent R 'groups formed together a divalent derivative which is a hydrocarbaryl-yl, siladi-yl or germadi-yl group; X 'is a conjugated diene having from 4 to 30 non-hydrogen atoms, which form a p-complex with M when M is in the formal oxidation state +2, whereby n is 1 and p is 0; X "each time it is presented is an anionic ligand group that is covalently bound to M when M is in the formal oxidation state +3 or +4, so n is 0 and p is 1 or 2 and optionally two X groups "together for a group of divalent anionic ligands. 9. The process of any of claims 1-8, wherein the cocatalyst comprises a boron-containing compound. The process of any of claims 1-9, wherein the molar ratio of the inhibitor to catalyst is at least 1000, the molar ratio of inhibitor to cocatalyst is at least 1000, or molar ratio of inhibitor to catalyst. and cocatalyst is at least 1000. 1 1. The process of any of claims 1 -10, wherein the step of mixing the inhibitor and olefin monomer precedes by a step of purifying the inhibitor to remove compounds that inhibit the activity of the catalyst. 12. A composition of matter produced by the process of any of claims 1 -1 1. 13. A composition comprising at least one olefin monomer, a monomer polymer, a metallocene catalyst having a transition metal of Group 3, Group 4 or Lantanide in the formal oxidation states +2, +3 or + 4 and at least one free radical inhibitor having sufficient substituents to hide the active inhibition group so that it does not undesirably inhibit the catalyst R * of transition metals of the formula: wherein XH is an active hydrogen group with X as an oxygen, nitrogen or sulfur; each R is independently an aryl or alkyl concealment group having enough atoms to form a tightly hidden XH group, sufficiently hidden to avoid the reaction of XH with the transition metal catalyst so that less than 50 percent of the catalyst is inhibited by the inhibitor; and each R 'is independently hydrogen or any inert substitution that does not undesirably interfere with the action of the active group or with the polymerization transition metal catalyst for any aluminum compounds present in at least 100: 1. 14. An article prepared of a composition of any of claims 12 or 13, which article exhibits greater resistance to free radical deterioration than it exhibits by a polyolefin having the same composition except without the inhibitor.