Patent Application
20050203255
1. Field of the Invention
The present invention relates to polypropylene derivatives
2. Background of the Art
It is known to prepare polyolefin polymers for many applications. For example, U.S. Pat. No. 5,707,722 to Akimoto, et al., discloses preparing a toner composed of a resin, a colorant, and a releasing agent wherein the releasing agent is a polyolefin polymer synthesized in the presence of a metallocene catalyst. U.S. Pat. No. 5,604,573 to Endo, et al., discloses preparing a developing apparatus for developing an electrostatic image using a resin that can be an isotactic polypropylene metallocene polymerization polymer.
Use of polyolefin polymers in, for example, toners as lubricants is reported in several patents. U.S. Pat. No. 6,063,536 to Ikeyama, et al., claims a toner including a propylene-based copolymer wax wherein the propylene-based copolymer has a weight average molecular weight determined by gel permeation chromatography of from 3,000 to 50,000, a melting point determined by differential scanning calorimetry of from 120° C. to 140° C., and a propylene content of at least 90 mole percent. U.S. Pat. No. 6,052,940 to Fukuzawa, et al., claims a toner for electrophotography, the toner at least containing a coloring agent, a binder resin, a charge control agent, and a functioning agent, wherein a low molecular weight polyolefin wax comprising co-polymers of alpha olefins with cycloolefins obtained by using a metallocene type polymerization catalyst is the functioning agent. U.S. Pat. No. 5,677,409 to Inoue, et al., claims a syndiotactic polypropylene wax having a syndiotactic pentad fraction of at least 0.7, a melting point in a range of 120-170° C. as measured by a differential scanning calorimeter.
In one aspect, the present invention is a polypropylene derivative comprising the reaction product of admixing: (a) a polypropylene homopolymer having a Mn of from about 300 to 10,000 daltons prepared by a process including polymerizing propylene in the presence of a metallocene catalyst at a temperature of from about 30 to about 120 degrees centigrade under reaction conditions sufficient to polymerize propylene; (b) a copolymer having a Mn of from about 300 to 10,000 daltons prepared by a process including polymerizing propylene and a co-monomer in the presence of a metallocene catalyst at a temperature of from about 30 to about 120 degrees centigrade under reaction conditions sufficient to polymerize the propylene and co-monomer; or (c) a mixture of (a) and (b), with a derivatizing agent or a series of derivatizing agents under reaction conditions sufficient to add to the polypropylene homopolymer or polypropylene copolymer or mixtures thereof, a functional group selected from the group consisting of alcohol, carboxylic acid ester, carboxylic acid anhydride, carboxylic acid, amine, amide, nitrile, imine, silane, siloxane, sulfonate, alkane, aldehyde, epoxide, alcohol, organoborane, ethoxylate, propoxylate, higher alkoxylate, and halogen functional groups.
In another aspect, the present invention is a compatibilizer comprising a polypropylene derivative comprising the reaction product of admixing: (a) a polypropylene homopolymer having a Mn of from about 300 to 10,000 daltons prepared by a process including polymerizing propylene in the presence of a metallocene catalyst at a temperature of from about 30 to about 120 degrees centigrade under reaction conditions sufficient to polymerize propylene; (b) a copolymer having a Mn of from about 300 to 10,000 daltons prepared by a process including polymerizing propylene and a co-monomer in the presence of a metallocene catalyst at a temperature of from about 30 to about 120 degrees centigrade under reaction conditions sufficient to polymerize the propylene and co-monomer; or (c) a mixture of (a) and (b), with a derivatizing agent or a series of derivatizing agents under reaction conditions sufficient to add to the polypropylene homopolymer or polypropylene copolymer or mixtures thereof, a functional group selected from the group consisting of alcohol, carboxylic acid ester, carboxylic acid anhydride, carboxylic acid, amine, amide, nitrile, imine, silane, siloxane, sulfonate, alkane, aldehyde, epoxide, alcohol, organoborane, ethoxylate, propoxylate, higher alkoxylate, and halogen functional groups.
Another aspect of the present invention is a coating comprising a compatibilizer comprising a polypropylene derivative comprising the reaction product of admixing: (a) a polypropylene homopolymer having a Mn of from about 300 to 10,000 daltons prepared by a process including polymerizing propylene in the presence of a metallocene catalyst at a temperature of from about 30 to about 120 degrees centigrade under reaction conditions sufficient to polymerize propylene; (b) a copolymer having a Mn of from about 300 to 10,000 daltons prepared by a process including polymerizing propylene and a co-monomer in the presence of a metallocene catalyst at a temperature of from about 30 to about 120 degrees centigrade under reaction conditions sufficient to polymerize the propylene and co-monomer; or (c) a mixture of (a) and (b), with a derivatizing agent or a series of derivatizing agents under reaction conditions sufficient to add to the polypropylene homopolymer or polypropylene copolymer or mixtures thereof, a functional group selected from the group consisting of alcohol, carboxylic acid ester, carboxylic acid anhydride, carboxylic acid, amine, amide, nitrile, imine, silane, siloxane, sulfonate, alkane, aldehyde, epoxide, alcohol, organoborane, ethoxylate, propoxylate, higher alkoxylate, and halogen functional groups.
In still another aspect, the present invention is a process for compatibilizing and/or improving the adhesion of a coating and surface upon which the coating is to be applied comprising admixing with the coating a compatibilizer comprising a polypropylene derivative comprising the reaction product of admixing: (a) a polypropylene homopolymer having a Mn of from about 300 to 10,000 daltons prepared by a process including polymerizing propylene in the presence of a metallocene catalyst at a temperature of from about 30 to about 120 degrees centigrade under reaction conditions sufficient to polymerize propylene; (b) a copolymer having a Mn of from about 300 to 10,000 daltons prepared by a process including polymerizing propylene and a co-monomer in the presence of a metallocene catalyst at a temperature of from about 30 to about 120 degrees centigrade under reaction conditions sufficient to polymerize the propylene and co-monomer; or (c) a mixture of (a) and (b), with a derivatizing agent or a series of derivatizing agents under reaction conditions sufficient to add to the polypropylene homopolymer or polypropylene copolymer or mixtures thereof, a functional group selected from the group consisting of alcohol, carboxylic acid ester, carboxylic acid anhydride, carboxylic acid, amine, amide, nitrile, imine, silane, siloxane, sulfonate, alkane, aldehyde, epoxide, alcohol, organoborane, ethoxylate, propoxylate, higher alkoxylate, and halogen functional groups.
Another aspect of the present invention is a process for compatibilizing a coating and surface upon which the coating is to be applied comprising applying a compatibilizer comprising a polypropylene derivative comprising the reaction product of admixing: (a) a polypropylene homopolymer having a Mn of from about 300 to 10,000 daltons prepared by a process including polymerizing propylene in the presence of a metallocene catalyst at a temperature of from about 30 to about 120 degrees centigrade under reaction conditions sufficient to polymerize propylene; (b) a copolymer having a Mn of from about 300 to 10,000 daltons prepared by a process including polymerizing propylene and a co-monomer in the presence of a metallocene catalyst at a temperature of from about 30 to about 120 degrees centigrade under reaction conditions sufficient to polymerize the propylene and co-monomer; or (c) a mixture of (a) and (b), with a derivatizing agent or a series of derivatizing agents under reaction conditions sufficient to add to the polypropylene homopolymer or polypropylene copolymer or mixtures thereof, a functional group selected from the group consisting of alcohol, carboxylic acid ester, carboxylic acid anhydride, carboxylic acid, amine, amide, nitrile, imine, silane, siloxane, sulfonate, alkane, aldehyde, epoxide, alcohol, organoborane, ethoxylate, propoxylate, higher alkoxylate, and halogen functional groups.
In still another aspect, the present invention is a process for coating a surface comprising determining the characteristics of a surface to be coated and then preparing a polypropylene derivative compatibilizer having a level isotacticity, syndiotacticity or atacticity such that the compatibilizer has an optimal level of compatibility with the surface to be coated.
In one aspect, the present invention is a derivative of a polypropylene homopolymer or copolymer, the homopolymer or copolymer being prepared by polymerizing propylene or propylene and a co-monomer in the presence of a metallocene catalyst. Metallocene catalysts are, in general, organometallic coordination compounds obtained as a potentially substituted cyclopentadienyl derivative of a transition metal or metal halide. Exemplary are dicylcopentadienyl-metals with the general formula (C5H5)2M, dicylcopentadienyl-metal halides with the general formula (C5H5)2MX1-3, and monocylcopentadienyl-metal compounds with the general formula (C5H5)MR1-3, where R is CO, NO, a halide group, an alkyl group, and the like, M is a metal and X is a halide. For example, catalyst #465 which is dimethylsilybis(1-methyl)-3-tert-butylcyclopentadienyl zirconium dichloride, from Boulder Scientific, is a preferred catalyst for use with the present invention.
For the purposes of the present invention, the metallocene catalysts which can be used with present invention include any that can be used to prepare the polypropylene derivatives of the present invention. Preferably, the catalysts are substituted ansa zirconocenes. Most preferably, the catalysts that are used with the present invention are those having the general formula:
Inherent in this formula are also the following formulae:
In the formulae, M1 is a metal of group IVb, Vb or V1b of the Periodic Table, for example titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, preferably titanium, zirconium and hafnium.
R1 and R2 are identical or different and are each a hydrogen atom, a C1-C10, preferably C1-C3-alkyl group, in particular methyl, a C1-C10, preferably C1-C3-alkoxy group, a C6-C10, preferably C6-C8-aryl group, a C6-C10, preferably C6-C8-aryloxy group, a C2-C10 preferably C2-C4-alkcnyl group, a C7-C40, preferably C7-C10-arylalkyl group, a C7-C40, preferably C7-C12-alkylaryl group, a C8-C40, preferably C8-C12-arylalkenyl group or a halogen atom, preferably chlorine.
R3 and R4 are identical or different and are each a monocyclic or polycyclic hydrocarbon radical that can form a sandwich structure with the central atom M1. R3 and R4 are preferably cyclopentadienyl, indenyl, benzindenyl or fluorenyl, where the base structures can also bear additional substituents or be bridged to one another. In addition, one of the radicals R3 and R4 can be a substituted nitrogen atom, where R24 is as defined for R17 and is preferably methyl, t-butyl or cyclohexyl.
R5, R5′, R6, R6′, R8, R8′, R9 and R9′ are identical or different and are each a hydrogen atom, a halogen atom, preferably a fluorine, chlorine or bromine atom, a C1-C10, preferably C1-C4-alkyl group, a C6-C10, preferably C6-C8-aryl group, a C1-C10, preferably C1-C3-alkoxy group, an —NR162—, —SR16—, —OSiR163—, —SiR163—, or —PR162, radical, where R16 is a C1-C10, preferably C1-C3-alkyl group or C6-C10, preferably C6-C8-alkyl group, or in the case of Si- or P-containing radicals is also a halogen atom, preferably a chlorine atom, or two adjacent radicals R5, R6, R8, R9 or together with the carbon atoms connecting them form a ring. Particularly preferred ligands are the substituted compounds of the base structures indenyl, benzindenyl, fluorenyl and cyclopentadienyl. R13 is
═BR17, ═AlR17, —Ge—, —Sn—, -0-, —S—, ═S0, ═S02 ═NR15, ═CO, ═PR15 or ═P(O)R15, where R17, R18 and R19 are identical or different and are each a hydrogen atom, a halogen atom, a C1-C30, preferably C1-C4-alkyl group, in particular a methyl group, a C1-C10fluoroalkyl group, preferably a CF3 group, a C6-C10-fluoroaryl group, preferably a pentafluorophenyl group, a C6-C10, preferably C6-C8-aryl group, a C1-C10, preferably C1-C4-alkoxy group, in particular a methoxy group, a C2-C10, preferably C2-C4-alkenyl group, a C7-C40, preferably C7-C10-arylalkyl group, a C8-C40, preferably C8-C12-arylalkenyl group or a C7-C40,-, preferably C7-C12-alkylaryl or R17 and R18 or R17 and R19, in each case together with the atoms connecting them, form a ring.
M2 is carbon, silicon, germanium or tin, preferably silicon or germanium.
R13 is preferably ═CR17R18, ═SiR17R18, ═GeR17R18, -0-, —S—, ═S0, ═PR17 or ═P(O)R17.
R11 and R12 are identical or different and are as defined for R17.
The symbols m and n are identical or different and are zero, 1 or 2, preferably zero or 1, where m plus n is zero, 1 or 2, preferably zero or 1.
R14 and R15 are as defined for R17 and R18.
Examples of suitable metallocenes are the rac isomers of: ethylenebis-1-(2-methyltetrahydroindenyl) zirconiumdichloride, ethylenebis-1-(4,7-dimethyl indenyl)zirconium dichloride, ethylenebis-1-(2-methyl4-phenylindenyl)zirconium dichloride, ethylenebis-1-(2-methyl-4,5-benzindenyl)zirconium dichloride, etbylenebis-1-(2-methyl-4,5-benzo-6,7-dihydroindenyl) zirconium dichloride, ethylenebis-1-(2-methylindenyl)zirconium dichloride, ethylenebis-1-tetrabydroindenylzirconium dichloride, and also the alkyl or aryl derivatives of each of these metallocene dichlorides.
To activate the single-center catalyst systems, suitable cocatalysts are used. Suitable cocatalysts for metallocenes of the formula I are organoaluminum compounds, in particular aluminoxanes, or aluminum-free systems such as R22xNH4-xBR234, R22x, PH4-xBR234, R223CBR234 or BR233. In these formulae, x is from 1 to 4, the radicals R22 are identical or different, preferably identical, and are C1-C10-alkyl or C6-C18-aryl or two radicals R22 together with the atom connecting them form a ring, and the radicals R23 are identical or different, preferably identical, and are C6-C18-aryl which may be substituted by alkyl, haloalkyl or fluorine. In particular, R22 is ethyl, propyl, butyl or phenyl and R23 is phenyl, pentafluorophenyl, 3,5-bis(trifluoromethyl)phenyl, mesityl, xylyl or tolyl.
These cocatalysts are particularly suitable in combination with metallocenes of the formula I when R1 and R2 are each a C1-C10-alkyl group or an aryl or benzyl group, preferably a methyl group. Derivative formation to give the metallocenes of the formula I can be carried out by literature methods, for example by reaction with alkylating agents such as methyllithium (cf. Organometalics 9 (1990) 1359; J. Am Chem. Soc. 95 (1973) 6263).
In addition, a third component is frequently necessary to provide protection against polar catalyst poisons. Organoaluminum compounds such as triethylaluminum, tributylaluminum and others, and also mixtures, are suitable for this purpose. Depending on the process, supported single-center catalysts can also be used. Preference is given to catalyst systems for which the residual contents of support material and cocatalyst in the product do not exceed a concentration of 100 ppm.
Another embodiment of the present invention is a polymer derivative wherein the polymer is an polypropylene copolymer. For the purposes of the present invention, a polypropylene copolymer is a polymer prepared with propylene and at least one other monomer. Compounds useful for preparing the copolymers of the present invention are any unsaturated monomer having from 2 to 30 carbons that can undergo polymerization with propylene without giving rise to significant levels of crosslinking. Exemplary compounds include alpha olefins, hindered dienes and the like. The polypropylene copolymers of the present invention can be prepared with from 0.1 to 50 mole percent co-monomers, but preferably are made with from about 1 to about 20 mole percent commoners, and most preferably are made with from about 2 to about 10 mole percent co-monomers.
The polypropylene derivatives of the present invention may be isotactic, syndiotactic, or even atactic. In a highly isotactic polymer it is the meso orientation of consecutive stereo-centers which predominate in the backbone of the polymer. This can be determined by 13C NMR analysis. In a highly syndiotactic polymer it is the racemo orientation of consecutive stereo-centers which predominate in the backbone of the polymer. This can be determined by 13C NMR analysis. In an atactic polymer there is no pattern of stereo-centers in the backbone of the polymer. It follows that polymers can vary in the degree of these properties and the degree of this structural organization can affect such properties as melting point, compatibility with other materials, and adhesion to other materials.
While the amount and type of tacticity of the polypropylene derivatives of the present invention may vary depending upon their intended end-use, some embodiments have a known desirable level of tacticity. For example, in certain embodiments, particularly in embodiments relating to coatings, the polypropylene derivative is a derivative of a polypropylene homopolymer having an isotacticity of from about 10 percent to 80 percent. In another embodiment, the derivative of a polypropylene homopolymer has an isotacticity of from about 10 percent to 39 percent. In still another embodiment, the polypropylene derivative has an isotacticity of from about 10 percent to 35 percent. In yet another embodiment, the polypropylene homopolymer derivative has a syndiotacticity of from about 15 percent to 30 percent.
The co-monomers which can be used to prepare the copolymer derivatives of the present invention preferably include: alpha olefins including butene, pentene, hexene, octene, styrene, isobutylene, and the like; hindered dienes including butadiene, isoprene, chloroprene, and the like. In some applications, it can be desirable to use less conventional co-monomers that add functionality to prepare a polypropylene copolymer. Co-monomers which impart added functionality such as allyl trimethylsilane, allyl benzene, norbornylene, vinyl chloride, vinyl silanes, vinyl siloxanes, vinyl ethers, isobutylene, and the like can also be used and are preferred.
The polypropylene derivatives of the present invention can be prepared by any method known to be useful to those of ordinary skill in the art of preparing such derivatives. Any method of producing the product of reacting the terminal unsaturation of a polypropylene with a compound that results in the formation of a hydroxy group, carboxy group or other functional group on the homopolymer or copolymer can be used with the present invention. For example, one such derivative can be prepared by reacting a polypropylene homo or copolymer with hydrogen peroxide and formic acid to form an epoxide. Additionally, the epoxide can be further reacted with zinc iodide to form an aldehyde, and so on. Additionally the aldehyde can be reduced to an alcohol using sodium borohydride. Additionally the epoxide can be reduced to the alcohol in one step by reacting with hydrogen in the presence of a transition metal catalyst.
These derivatives of the present invention can also function as intermediates in the preparation of other derivatives. For example, a first derivative having a primary hydroxyl group can be reacted with ethylene oxide or propylene oxide in the presence of a base to form a polyether alcohol. The resultant derivative polymers will have a backbone of a polypropylene homopolymer or copolymer but will terminate with a group having a relative high reactivity including but not limited to: alcohols, amines, amide, imides, carboxylates, carboxylic acid esters, carboxylic acid anhydrides, and the like.
There are yet additional derivatives of polypropylene homopolymers and copolymers of the present invention. The additional derivatives are saturated polymers prepared by adding hydrogen across the terminal double bond of a polypropylene homopolymer or copolymer of the present invention. These derivatives are prepared by any method of hydrogenating a polymer known to one of ordinary skill in the art of preparing saturated polymers.
The polypropylene derivatives may also include polypropylene polyfunctional polymers. For example, one such polymer is prepared by the reaction pf polypropylene homopolymer with maleic anhydride and a radical source such as a peroxide to graft multiple anhydride groups onto the polymer molecule. These functional groups include but are not limited to: alcohols, amines, amides, imides, carboxylates, esters, carboxylic acid anhydrides, and the like.
The melting point, as measured by Differential Scanning Calorimetry (DSC) of a polypropylene polymer depends on the type of tacticity, amount of tacticity, and molecular weight. Polypropylene polymers with high degrees of either isotacticity or syndiotacticity will have high melting points, potentially exceeding 150° C. Lower levels of either isotacticity or syndiotacticity cause the DSC melting points to decrease. Atactic polypropylene derivates, being amorphous, do not have a DSC melting point but do decrease in viscosity as a function of temperature. The preferred polypropylenes for this invention will vary depending on the nature of materials for compatibilization/adhesion promotion. Optimum compatibility and adhesion promotion will be a function of isotacticity, molecular weight, and melting point. This is best determined by experimentation.
The polypropylene derivatives of the present invention, particularly those containing polar groups such as maleic and succinic acids and acid anhydrides, alkoxylates, ethers, alcohols, and amines may be especially useful as compatibilizers and adhesion promoters. These derivatives may be used to compatibilize and promote adhesion between two materials which would otherwise be incompatible. For example, the comparatively non-polar backbone of a derivative of the present invention can be prepared with a polar functional group such as a maleic group to compatibilize a polar material and a non-polar material. The compatibilizers also can be effective adhesion improvers capable of improving the adhesion of a coating and a surface to be coated. For the purposes of the present invention, the term compatibilizer also means adhesion improver.
Another aspect of the present invention is that it may be modified to suit it intended use in relation to the structure of the polypropylene portion of the derivative. For example, if the polypropylene derivative is to be use to compatibilize a polar compound and a surface that is more compatible with an isotactic polypropylene, then the isotacticity of the derivative of the present invention can be increased. Similarly, the atacticity or syndiotacticity can be modified. This is done through selection of the metallocene catalyst and the polymerization conditions and would be known to one of ordinary skill in the art.
The compatibilizers of the present invention can be admixed with a coating and then the coating applied to a surface. In another embodiment, the compatibilizer can be applied first to a surface and the then the coating can be applied to the surface.
When applied directly to the surface, the compatibilizers of the present invention can also include solvents, carriers, and stabilizers.
The following examples are provided to illustrate the present invention. The examples are not intended to limit the scope of the present invention and they should not be so interpreted. Amounts are in weight parts or weight percentages unless otherwise indicated.
A polyolefin derivative is prepared. 80 g of polypropylene (0.11 moles), 20 g maleic anhydride (0.2 moles), 1.25 g butylated hydroxy toluene (BHT), and 40 g xylenes are placed into a steel pressure reactor forming an admixture. The polypropylene has a Mn of 700, 32% isotactic pentads (13C NMR), and a melting point of 82° C. (determined by means of a differential scanning calorimeter (DSC) peak) and was prepared using a metallocene catalyst and had a terminal vinylidene group on substantially all the molecules as determined by 13C NMR. The admixture is heated to 200° C. for 18 hours with continuous stirring. The admixture is cooled to allow handling and poured into a tray. The tray is heated to 150° C. under vacuum to remove solvent, excess maleic anhydride, and BHT. The conversion is essentially complete based on the disappearance of the vinylidene peaks and the appearance of the succinic anhydride carbonyl peaks in the 13C NMR spectrum.
This application is a continuation-in part of U.S. patent application Ser. No. 10/433,164, filed on May 3, 2003 as a filing under Rule 35 U.S.C. §371 from PCT/US01/48725, filed 12 Dec. 2001, which claimed priority from U.S. Provisional Patent Application 60/255,035, filed on 12 Dec. 2000.
| Number | Date | Country | |
|---|---|---|---|
| 60255035 | Dec 2000 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 10433164 | May 2003 | US |
| Child | 11035480 | Jan 2005 | US |
