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(12) United States Patent (10) Patent No.: US 6,897.278 B2 Wilczek (45) Date of Patent: May 24, 2005

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(12) United States Patent (10) Patent No.: US 6,897.278 B2 Wilczek (45) Date of Patent: May 24, 2005 USOO6897278B2 (12) United States Patent (10) Patent No.: US 6,897.278 B2 Wilczek (45) Date of Patent: May 24, 2005 (54) BRANCHED POLYOLEFIN SYNTHESIS K. Ishizu et al., Synthesis of AB Type Diblock Macromono mers, J. Poly. Sci. Polym. Chem., 29,923–927, 1991. (75) Inventor: Lech Wilczek, Wilmington, DE (US) J. J. Ma et al., Poly(ethylene-co-propylene)-g-polystyrene (73) Assignee: E. I. du Pont de Nemours and through Macomer Polymerization: Preparation, Morphol Company, Wilmington, DE (US) ogy, and Structure-Properties Relationships, J. Poly. Sci. Polym. Chem., 24, 2853–2866, 1986. (*) Notice: Subject to any disclaimer, the term of this P. Chaumont et al., Synthese Anionique de Polymeres Com patent is extended or adjusted under 35 portant Une Fonction Vinylsilane a Lune ou aux deux U.S.C. 154(b) by 184 days. extremites de la Chaine Macromoleculaire, Eur: Polym. J., 15, 537-540, 1979. (21) Appl. No.: 10/772,194 Y. Gnanou et al., The Ability of Macromonomers to Copo (22) Filed: Feb. 4, 2004 lymerize: A Critical Review with New Developments, Mak (65) Prior Publication Data romol. Chem., 190, 577–588, 1989. M. Arnold et al., On the Reactivity of Syryl-Terminated US 2004/0167305 A1 Aug. 26, 2004 Polystyrene Macromonomers in Anionic Copolymerization Related U.S. Application Data with Butadiene, Makromol. Chem., 192, 285–292, 1991. Slagowski et al., Upper Molecular Weight Limit for the (60) Division of application No. 10/316,454, filed on Dec. 11, 2002, now Pat. No. 6,740,723, which is a continuation-in Characterization of Polystyrene in Gel Permeation Chroma part of application No. 09/462.969, filed on Jan. 14, 2000, tography, Macromolecules, 7, 394–396, 1974. now Pat. No. 6,518,383, which is a continuation-in-part of application No. PCT/US98/14833, filed on Jul. 16, 1998. Asami et al., Synthesis of Macromers by Means of Living (60) Provisional application No. 60/052,859, filed on Jul. 17, Polymers and their Polymerizabilities, Makromol. Chem. 1997. Suppl., 12, 163–173, 1985. (51) Int. Cl." ............................................... C08F 114/16 P. Remp et al., Macromonomers: A new class of polymeric (52) U.S. Cl. ....................... 526/291; 526/296; 526/297; intermediates in macromolecular synthesis-II-home and 526/318; 526/319; 526/346 copolymerization, Makromol. Chem. Suppl., 13, 46-66, (58) Field of Search ................................. 526/291, 296, 1985. 526/297, 319, 318, 346 G. Odian, Principles of Polymerization, 1981, Chapter 1 to 3. Linear, branched, and croSS-linked polymers, pp. 18 to (56) References Cited 2O. U.S. PATENT DOCUMENTS 3,235,626 A 2/1966 Waack * cited by examiner 3,390,206 A 6/1968 Thompson et al. 3,514,500 A 5/1970 Osmond et al. Primary Examiner William K. Cheung 3,786,116 A * 1/1974 Milkovich et al. .......... 525/276 (74) Attorney, Agent, or Firm-Sudhir G. Deshmukh FOREIGN PATENT DOCUMENTS (57) ABSTRACT WO WO 95.12568 A1 5/1995 This invention relates to a proceSS for the Synthesis of OTHER PUBLICATIONS addition polymers containing branches upon branches and R. Asami et al., Prepartion of (p-Vinylbenzyl)polystyrene having a polymerizable olefin end group by a convenient Macromer, Macromolecules, 16, 628-631, 1983. one-pot polymerization of Selected vinyl monomers with P. Remp et al., Macromonomers: Synthesis, Characteriza chain polymerization initiators and a method to provide tion and Application, Advances in Polymer Science, 58, olefinic end groups by chain termination agents, and poly 3–53, 1984. merS produced thereby characterized by branch-on-branch Y. Tsukahara et al., Radical Polymerization Behavior of Structure and lower inherent Viscosity than heretofore pos Macromonomers. 2. Comparison of Styrene Macromono sible. mers Having a Methacryloyl End Group and a Vinylbenzyl End Group, Macromolecules, 23, 5201–5208, 1990. 2 Claims, No Drawings US 6,897.278 B2 1 2 BRANCHED POLYOLEFIN SYNTHESIS olefin end groups by chain termination agents. The poly merization is carried out in Such a manner that chain This application is a divisional of a continuation-in-part termination occurs gradually and each chain termination of U.S. Ser. No. 10/316,454 filed on Dec. 11, 2002 now U.S. event terminates that particular polymer chain with poly Pat. No. 6,740,723, which is a continuation-in-part of U.S. merizable olefinic functionality. Subsequent reincorporation application Ser. No. 09/462.969, filed Jan. 14, 2000, issued of the linear polymer chains produced early in the reaction as U.S. Pat. No. 6,518,383 on Feb. 11, 2003, which is a leads to branching of Subsequently-formed macromolecules continuation in part of application No. PCT/US98/14833 which are terminated with polymerizable olefinic function which claims the benefit of priority from U.S. Provisional ality. Subsequent reincorporation of the branched macro Application No. 60/052,859, filed Jul. 17, 1997. molecules leads to Subsequently-formed polymer molecules containing branches upon branches which are terminated BACKGROUND OF THE INVENTION with polymerizable olefinic functionality. Spontaneous rep etition of the proceSS leads to highly branched or hyper Macromolecular engineering using commodity mono branched dendritic products still retaining polymerizable merS is becoming a major trend in polymer technology to olefinic termini. Satisfy the demand for new properties, improved cost 15 effectiveness, ecology and quality. Functional polymers with This invention concerns an improved process for the low molecular weight, low polydispersity, compact, anionic polymerization of at least one vinylic monomer to branched Structures and terminally-located reactive groups form a branched polymer comprising contacting, in the are expected to exhibit Superior performance/cost presence of an anionic initiator: characteristics, by Virtue of lower inherent Viscosity and (i) one or more anionically polymerizable vinylic mono higher reactivity VS. conventional linear Statistical copoly mers having the formula CH=CYZ, and CS. (ii) an anionic polymerization chain terminating agent of The terminally-functional branched polymers appear to formula CH=CZ-Q-X, be ultimate reactive Substrates for networks, because the wherein: branch points can Substitute for a significant portion of Q is Selected from the group consisting of a covalent expensive reactive groups and provide better distribution of 25 bond, -R-, -C(O), and -R-C(O)-; the reactive groups. Polymers having large numbers of short Y is selected from the group consisting of R, COR, CN, branches below critical molecular weight are unlikely to and NR; form any entanglements and should exhibit low inherent Viscosity and good flow even in concentrated Solutions. X is Selected from the group consisting of halogen, and Conventional techniques for Synthesizing well-defined RSO; branched polymers require expensive multistep processes Z is Selected from the group consisting H, R, and CN; involving isolation of reactive intermediate macromono R is selected from the group consisting of unsubstituted mers. The macromonomers have polymerizable end groups, and Substituted alkyl, Vinyl, aryl, aralkyl, alkaryl and which are usually introduced using functional initiator, organosilanyl groupS and R' is Selected from the group terminating or chain transfer agent. Well-defined branched 35 consisting of Substituted or unsubstituted alkylene, polymers are prepared by the macromonomer homopoly arylene, aralkylene, alkarylene and organosilanylene merization or copolymerization with Suitable low molecular groups; the Substituents being the Same or different and weight comonomer Selected based on known reactivity Selected from the group consisting of carboxylic acid, ratios. These methods have been reviewed and only single carboxylic ester, hydroxyl, alkoxy and amino; branch polymers from Single incorporation of the mac 40 wherein the improvement comprises obtaining higher romonomers are reported; multiple reincorporation of the yields of branched polymer, the polymer having dense growing macromonomers was never attempted, e.g., R. branch upon branch architecture and polymerizable Milkovich, et al., U.S. Pat. No. 3,786,116; P. REMP, et al., Vinylic chain termini, employing Steps I, III, VI and at Advan. Polymer Sci., 58, 1 (1984); J. C. Salamone, ed., least one of II, IV and V. Polymeric Materials Encyclopedia, Vol. 3 and 4 (1996). 45 Several linear macromonomers were prepared by end I. reacting (i) with an anionic initiator in a first step: capping of living anionic polyolefins with unsaturated ter II. decreasing the ratio of (i) to anionic initiator toward 1; minating agents providing polymerizable olefin end-groups, III. adding (ii) optionally with Some (i) in a Second step; e.g., R. Asami et al., Macromolecules, 16, 628 (1983). IV. Selecting the rate of the (ii) addition, dependent on the Certain macromonomers have been incorporated into Simple (ii) reactivity; graft polymers by homo- or copolymerization with branched 50 V. increasing the ratio of (ii) to anionic initiator toward 1; Structure not well-characterized and reincorporation of the and macromonomers into more complex Structures was not VI. increasing the conversion of (i), (ii) and olefinic end considered. groups from 70 to 100%. Dendrimers or hyperbranched polymers are convention Based on the disclosure and Examples presented herein, ally prepared using expensive, Special multifunctional 55 one skilled in the art can select the optimum steps I-VII with monomers or expensive multistep methods requiring repeti minimum experimentation. One skilled in the art will also be
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