WO2006031971A1 - Materials leading to dental composites - Google Patents

Materials leading to dental composites Download PDF

Info

Publication number
WO2006031971A1
WO2006031971A1 PCT/US2005/032940 US2005032940W WO2006031971A1 WO 2006031971 A1 WO2006031971 A1 WO 2006031971A1 US 2005032940 W US2005032940 W US 2005032940W WO 2006031971 A1 WO2006031971 A1 WO 2006031971A1
Authority
WO
WIPO (PCT)
Prior art keywords
formula
carbon atoms
composite material
dental composite
compound
Prior art date
Application number
PCT/US2005/032940
Other languages
English (en)
French (fr)
Inventor
Samuel David Arthur
Donald Da-Jen Huang
Gary Delmar Jaycox
Gary Brent Douglas
Andrew P. Stamengna
Lech Wilczek
Gordon Mark Cohen
Charles J. Brandenburg
Original Assignee
E.I. Dupont De Nemours And Company
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by E.I. Dupont De Nemours And Company filed Critical E.I. Dupont De Nemours And Company
Publication of WO2006031971A1 publication Critical patent/WO2006031971A1/en

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F2/00—Processes of polymerisation
    • C08F2/38—Polymerisation using regulators, e.g. chain terminating agents, e.g. telomerisation
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K6/00—Preparations for dentistry
    • A61K6/20—Protective coatings for natural or artificial teeth, e.g. sealings, dye coatings or varnish
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K6/00—Preparations for dentistry
    • A61K6/30—Compositions for temporarily or permanently fixing teeth or palates, e.g. primers for dental adhesives
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K6/00—Preparations for dentistry
    • A61K6/80—Preparations for artificial teeth, for filling teeth or for capping teeth
    • A61K6/884—Preparations for artificial teeth, for filling teeth or for capping teeth comprising natural or synthetic resins
    • A61K6/887—Compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F2/00—Processes of polymerisation
    • C08F2/46—Polymerisation initiated by wave energy or particle radiation
    • C08F2/48—Polymerisation initiated by wave energy or particle radiation by ultraviolet or visible light
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F222/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a carboxyl radical and containing at least one other carboxyl radical in the molecule; Salts, anhydrides, esters, amides, imides, or nitriles thereof
    • C08F222/10—Esters
    • C08F222/1006—Esters of polyhydric alcohols or polyhydric phenols
    • C08F222/103—Esters of polyhydric alcohols or polyhydric phenols of trialcohols, e.g. trimethylolpropane tri(meth)acrylate
    • C08F222/1035—Esters of polyhydric alcohols or polyhydric phenols of trialcohols, e.g. trimethylolpropane tri(meth)acrylate of aromatic trialcohols

Definitions

  • This invention relates to composite materials for restorative dentistry. More particularly, it relates to new components for dental composites that impart an attractive combination of good mechanical properties and low shrinkage.
  • composite materials comprising highly filled polymers have become commonly used for dental restorations.
  • Current composite materials contain crosslinking acrylates or methacrylates, inorganic fillers such as glass or quartz, and a photoinitiator system suitable for curing by visible light.
  • Typical methacrylate materials include 2,2'-bis[4-(2-hydroxy-3-methacryloyloxypropyl)phenyl]propane ("Bis- GMA”); ethoxylated Bisphenol A dimethacrylate (“EBPDMA”); 1 ,6-bis-[2- methacryloyloxyethoxycarbonylamino]-2,4,4-trimethylhexane (“UDMA”); dodecanediol dimethacrylate (“D 3 MA”); and triethyleneglycol dimethacrylate (“TEGDMA”).
  • Bis- GMA 2,2'-bis[4-(2-hydroxy-3-methacryloyloxypropyl)phenyl]propane
  • EBPDMA ethoxylated Bisphenol A dimethacrylate
  • UDMA 1- ,6-bis-[2- methacryloyloxyethoxycarbonylamino]-2,4,4-trimethylhexane
  • D 3 MA dodecanedi
  • Dental composite materials offer a distinct cosmetic advantage over traditional metal amalgam. However, they do not offer the longevity of amalgam in dental fillings. The primary reasons for failure are excessive shrinkage during photopolymerization in the tooth cavity, which causes leakage and bacterial reentry. Another reason is they have inadequate strength and toughness, as reflected in the measured properties of flexural strength and fracture toughness. Hence, there is still a need for new monomers and new monomer combinations which, when polymerized, impart high fracture toughness and flexural strength in the resulting composite. It is also highly desirable to have low shrinkage and low shrinkage stress on polymerization.
  • One of the more common commercially used monomer is Bis-GMA, making it an especially important monomer in dental composites.
  • Bis-GMA is highly viscous at room temperature and is insufficiently converted to polymer when cured. It is therefore diluted with a second, lower viscosity polymerizable component, typically an acrylate or methacrylate monomer, such as trimethylol propyl trimethacrylate, 1 ,6- hexanediol dimethacrylate, 1 ,3-butanediol dimethacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, TEGDMA, or tetraethylene glycol dimethacrylate.
  • acrylate or methacrylate monomer such as trimethylol propyl trimethacrylate, 1 ,6- hexanediol dimethacrylate, 1 ,3-butanediol dimethacrylate, ethylene glycol dimethacryl
  • Culbertson describes the synthesis of trimethacrylate dental monomers derived f rom 1 ,1 ,1 -tris(4- hydroxyphenyl) ethane (THPE). Culbertson treats THPE with ethylene or propylene carbonate, then caps the hydroxyl group with methacrylic anhydride:
  • THPE EO MA 1 ,1 ,1-tri[4-methacryloxyethoxy)-phenyl]ethane
  • THPE PO MA 1 ,1 ,1-tri[4-2-methyl-2- methacryloxyethoxy)-phenyl]ethane
  • Branched polyester methacrylates are another class of new dental monomers.
  • Culbertson, et al. used a variety of synthetic routes to methacrylate Boltorn H30, a commercially available polyester polyol with a dendritic structure (Perstorp AB, Perstorp, Sweden) that is synthesized by a condensation reaction of a pentaerythritol core with 2,2- dimethylolpropionic acid.
  • the methacrylated Boltorn H30 was intended as a replacement for at least some of the Bis-GMA in dental composite materials.
  • macromonomers with olefinic end groups. These are described by, for example, Macromolecules (1996), 29, 7717. These materials are usually prepared by polymerization of methacrylate monomers in the presence of a "catalytic chain transfer” (CCT) catalyst. The catalyst is typically a chelated cobalt species. Macromonomers have been described for use in automotive coatings, but not for dental composite applications. There remains a need for dental composite materials that combine reduced shrinkage with sufficiently low viscosity, high polymerization rate, and acceptable mechanical properties.
  • CCT catalytic chain transfer
  • the present invention is a compound having the Formula I:
  • each R 4 is independently an alkylene having 2 or 3 carbon atoms
  • each R 5 is independently an alkylene having 2 to 7 carbon atoms
  • each R 6 is independently an alkylene having 2 to 5 carbon atoms
  • m is an integer of 1 to 10
  • n is an integer of 1 to 10.
  • the present invention is a new (meth)acrylated hyperbranched polyester polyol that is suitable for use in dental composite materials.
  • the present invention is an uncured dental composite material incorporating the compound of Formula I and the new (meth)acrylated hyperbranched polyester polyol.
  • the present invention is an uncured dental composite material incorporating a compound of the Formula IV
  • each Y is -COOR 17 , where each R 17 is independently selected from the group consisting of hydrogen, substituted or unsubstituted straight, branched, or cyclic alkyl having 1 to 20 carbon atoms, aryl, benzyl, and -(CH 2 )nSi(OCH 3 ) 3 wherein n is 2 to 5.
  • the present invention is an uncured dental composite material incorporating a compound of the Formula V
  • each A is a repeat unit of the formula
  • each R 4 is independently an alkylene having 2 or 3 carbon atoms
  • each R 5 is independently an alkylene having 2 to 7 carbon atoms
  • each R 6 is independently an alkylene having 2 to 5 carbon atoms
  • m is an integer of 1 to 10
  • n is an integer of 1 to 10.
  • dental composite material denotes a composition that can be used to remedy natural or induced imperfections in, or relating to, teeth. Examples of such materials are filling materials, reconstructive materials, restorative materials, crown and bridge materials, inlays, onlays, laminate veneers, dental adhesives, teeth, facings, pit and fissure sealants, cements, denture base and denture reline materials, orthodontic splint materials, and adhesives for orthodontic appliances.
  • uncured dental composite material specifically refers to such material before it is subjected to curing processes.
  • Dendrimers are macromolecules having a highly regular tree-like structure. “Hyperbranched” polymers resemble dendrimers, but are less regularly structured. As used herein, the term “hyperbranched polymer” refers to both dendrimers and such less regularly structured polymers.
  • macromonomer as used herein means an oligomer of limited chain length or molecular weight that contains at least one terminal olefinic moiety.
  • alkyl means a univalent group derived from an alkane by removing a hydrogen atom from any carbon atom: -C n H 2n +i where n >1.
  • hydrocarbyl when used in relation to a radical, denotes a univalent radical containing only carbon and hydrogen.
  • hydrocarbyl moiety denotes a chemical group that contains only carbon and hydrogen and may be able to form more than one single covalent bond; the term may encompass straight chain, branched chain, cyclic, aromatic species, and structures combining combinations of the foregoing.
  • alkylene means the divalent radical derived from an alkane by removing a hydrogen atom from each of two different carbon atoms: -C n H 2n - where n >1.
  • an alicyclic group means a non-aromatic hydrocarbon group containing a cyclic structure therein.
  • benzyl refers to the C 6 H 5 CH 2 - radical.
  • phenyl refers to the C 6 H 5 - radical.
  • phenylene refers to the divalent radical, .
  • aryl means a univalent group whose free bonding site is to a carbon atom of an aromatic ring.
  • An example is the "phenyl” group.
  • hydroxy carboxylic acid means an organic compound containing both -COOH and hydroxyl groups.
  • carboxy methacrylate means a compound containing a carboxylic acid and a methacrylate group.
  • (meth)acrylic and (meth)acrylate refer to both methacrylic and acrylic and to methacrylate and acrylate, respectively.
  • polymerizable (meth)acrylic ester component means one or more materials that bear (meth)acrylate groups, such that the materials are capable of undergoing free radical polymerization.
  • polyol means an organic compound having more than one hydroxyl (-OH) group per molecule.
  • caprolactone means e-caprolactone, CAS Registry # 502-44-3:
  • the present invention provides a compound of the Formula I, as shown below.
  • each R 1 is independently hydrogen or methyl
  • R 2 is an alkylene having 2 to 14 carbon atoms, or an alkenylene having 2 to 8 carbon atoms, or a divalent alicyclic hydrocarbon having 5 to 14 carbon atoms, or a phenylene that is optionally substituted with halogen or an alkyl group having 1 to 5 carbon atoms
  • each R 3 is independently selected from the group consisting of hydrogen, acetyl, methyl, ethyl, C 3-6 linear or branched alkyl, and benzyl
  • R 7 is selected from the group consisting of hydrogen, methyl, ethyl, C 3-6 linear or branched alkyl, phenyl, and benzyl
  • A is a repeat unit of the formula:
  • each R 4 is independently an alkylene having 2 or 3 carbon atoms; each R 5 is independently an alkylene having 2 to 7 carbon atoms; each R 6 is independently an alkylene having 2 to 5 carbon atoms atoms; m is an integer of 1 to 10; and n is an integer of 1 to 10.
  • the preferred structure is one in which each R 1 is methyl; each R 2 is -(CH 2 CH 2 )- ; each R 3 is H;
  • R 7 is methyl
  • A is: O R 6 wherein:
  • R 6 is -(CH 2 CH 2 )- .
  • One method of preparing the compound of Formula i is the following:
  • Triepoxides of formula Il are commercially available.
  • Other compounds of formula Il (where R 7 is defined as above) can be prepared by the scheme below.
  • a compound of formula Il is treated with at least three moles of the carboxy methacrylate compound of formula III.
  • the carboxylic acid of formula III opens the epoxide rings in formula Il to give the desired product.
  • Suitable carboxy methacrylate compounds can be prepared by treatment of, for example, hydroxyethyl (meth)acrylate or hydroxypropyl (meth)acrylate with a cyclic anhydride to give the corresponding carboxy methacrylate compound.
  • Suitable anhydrides include succinic anyhydride, maleic anhydride, and phthalic anhydride.
  • Other suitable anhydrides include, for example, the following:
  • MIA carboxy methacrylates
  • carboxy methacrylates are described in U. S. Patent 4,883,899, CoI 2, line 37 to CoI 3, line 17.
  • hydroxyethyl methacrylate is used as an initiator for the ring opening polymerization of caprolactone.
  • the resulting hydroxy methacrylates are commercially available from Daicel Chemical Industries, Ltd. (Tokyo, Japan) under the trade name Placcel.
  • Placcel FM 3 is the addition product of hydroxyethyl methacrylate with three moles of caprolactone. These products can be reacted with cyclic anhydrides to give carboxy functional methacrylates useful in the present invention.
  • Catalysts for the reaction may include any known in the art for the reaction of carboxylic acids with epoxides. They may include nitrogen- containing compounds such as triethylamine, imidazole, 2-methyl imidazole, N,N-dimethyl benzyl amine, pyridine, and the like. They may include Lewis acids such as zinc acetate or zinc stearate. (Meth)acrylated hyperbranched polyester polvols
  • the present invention also provides new (meth)acrylated hyperbranched polyester polyols that are suitable for use in dental composite materials. These are produced by a process of (1 ) preparing a hyperbranched polyester polyol, and (2) converting all or part of the terminal hydroxyl groups of the hyperbranched polyester polyol to (meth)acrylate groups.
  • the hyperbranched polyester polyols can be produced by heating a mixture that includes:
  • one or more chain extenders selected from the group consisting of a hydroxy carboxylic acid, a lactone of a hydroxy carboxylic acid, a linear ester of a hydroxyl carboxylic acid, and a combination thereof, said hydroxy carboxylic acid and linear ester having the structural formula: O
  • each R 8 is independently H or R 14 — C; O
  • R 11 is H or R 14 — C
  • R 9 is a Ci -12 hydrocarbyl moiety capable of forming m+n single covalent bonds
  • R 10 is H or a Ci-- I2 hydrocarbyl radical
  • R 12 is a C 1 - 12 hydrocarbyl moiety capable of forming two single covalent single bonds
  • R 13 is H or a Ci_i 2 hydrocarbyl radical
  • R 14 is H or a C-M O hydrocarbyl radical
  • n+m ranges from 3 to 6, and either n or m must be 1 ; and, optionally,
  • R 15 is a C 1 -1 0 hydrocarbyl moiety capable of forming from 1 to 6 single covalent bonds;
  • Z is a hydroxyl, carboxyl, amine or epoxy group; and
  • k ranges from
  • Suitable hyperbranching monomers include those having one carboxyl group and two hydroxyl groups, two carboxyl groups and one I hydroxyl group, one carboxyl group and three hydroxyl groups, or three carboxyl groups and one hydroxyl group.
  • Some of the suitable hyperbranching monomers include dialkylol propionic acid, such as dimethylolpropionic acid (DMP) and diethylolpropionic acid; trimethylolacetic acid; citric acid; malic acid; and a combination thereof.
  • DMP is the preferred hyperbranching monomer for use in the present invention.
  • the chain extender is selected from the group consisting of a hydroxy carboxylic acid, a lactone of a hydroxy carboxylic acid, a linear ester of a hydroxy carboxylic acid, and a combination thereof.
  • Suitable hydroxy carboxylic acids include glycolic acid; lactic acid; and 3-hydroxy carboxylic acids, e.g., 3-hydroxypropionic acid, 3-hydroxybutyric acid, 3-hydroxyvaleric acid, and hydroxypivalic acid.
  • suitable lactones include caprolactone; ⁇ - valerolactone; and lactones of hydroxy carboxylic acids, such as, glycolic acid; lactic acid; and 3-hydroxy carboxylic acids, such as, 3- hydroxypropionic acid, 3-hydroxybutyric acid, 3-hydroxyvaleric acid, and hydroxypivalic acid.
  • Caprolactone is the preferred chain extender for use in the present invention.
  • the weight ratio of the hyperbranching monomer to the chain extender in the mixture ranges from 1/0.3 to 1/20, preferably from 1/1 to 1/10 and more preferably from 1/1.5 to 1/4.
  • the mixture can further include one or more molecular weight controlling agents having in the range of 1 to 6 functionalities selected from the group consisting of hydroxyl, amine, epoxide, carboxyl and a combination thereof.
  • suitable molecular weight controlling agents can include polyhydric alcohols, such as ethylene glycol, propanediols, butanediols, hexanediols, neopentylglycol, diethylene glycol, cyclohexanediol, cyclohexanedimethanol, trimethylpentanediol, ethylbutylpropanediol, ditrimethylolpropane, trimethylolethane, trimethylolpropane, glycerol, pentaerythritol, dipentaerythritol; polyalkylene glycol, such as, polyethylene glycol and polypropylene glycol.
  • Monohydric alcohols can be also used,
  • the preferred polyhydric alcohols are d ⁇ trimethylolpropane, trimethylolethane, trimethylolpropane and pentaerythritol.
  • Pentaerythritol is a particularly preferred molecular weight controlling agent for use in the present invention.
  • the preferred hyperbranched polyester polyols for use in the present invention involve the reaction of caprolactone, DMP, and pentaerythritol.
  • the highly branched polyester polyols can be produced by heating (to induce polymerization), in one step, the mixture that includes the chain extender and the hyperbranching monomer. If desired, the mixture in the foregoing one-step polymerization process can also include the molecular weight controlling agent.
  • a modification of the foregoing process is to produce the hyperbranched polyester polyol in two stages.
  • the first stage involves heating the molecular weight controlling agent, the hyperbranching monomer, and only a portion of chain extender to produce an intermediate product, followed by heating the intermediate product with the remainder of the chain extender.
  • the process involves using from 10 to 90, preferably 20 to 60 and more preferably 30 to 40 weight percent of the chain extender in the first stage, the remainder of the chain extender being used during the second stage.
  • the hyperbranched polyester polyols produced by the processes described above can be prepared by a batch process or by a continuous polymerization process.
  • the processes for forming the hyperbranched polyester polyol take place at reaction temperatures in the range of from 60 0 C to 200 0 C and preferably, in the range of from 80°C to 170 0 C, with typical reaction times ranging from 1 hour to 24 hours, preferably 1 hour to 4 hours.
  • the polymerization can be catalyzed by conventional polyester polymerization catalysts, as described below.
  • the hyperbranched polyester polyol reaction product to be used in the present invention preferably has a number average molecular weight not exceeding 30,000, preferably in the range of from 1 ,000 to 30,000, more preferably in the range of 2,000 to 20,000, most preferably in the range of 5,000 to 15,000.
  • the Tg (glass transition temperature measured at 10°C/min. heating rate) of the hyperbranched polyester polyol reaction product preferably ranges from -70 0 C to 50 0 C, preferably from -65°C to 4O 0 C, and more preferably from -60°C. to 30°C.
  • the hyperbranched polyester polyol is then combined and optionally heated with one or more end capping agents having the formula
  • R 16 is a Ci- 12 hydrocarbyl radical and X is a carboxylic acid, carboxylic ester, carboxylic halide, or epoxy group, or having the formula
  • R 16 is a Ci-- I2 hydrocarbyl radical and X is a carboxylic anhydride group, provided that the resulting degree of end capping is at least 25%, with radically polymerizable end groups constituting at least 25% of all end groups.
  • the degree of capping with radically polymerizable end groups can be determined by a combination of 1 H NMR, 13 C NMR and two- dimensional NMR spectroscopy.
  • the conversion of hydroxyl groups to (meth)acrylate groups may be carried out according to any method known in the art.
  • Preferred end capping agents are methacrylic acid, methacrylic anhydride, and methacryloyl chloride.
  • Another option is to methacrylate only a portion of the hydroxyl groups and then treat the remaining hydroxyl groups with another reagent that is not capable of participating in free radical polymerization when the uncured dental composite is cured.
  • a portion of the hydroxyl groups can be capped with methacrylic anhydride, and the remaining hydroxyl groups can be capped with acetic anhydride.
  • a preferred (meth)acrylated hyperbranched polyester polyol can be made by a process comprising the steps of: (a) combining caprolactone, pentaerythritol, dimethylolpropionic acid, at least one aromatic solvent, and a polyester polymerization catalyst;
  • step (b) heating the product of step (a) to a temperature between about 170°C and 200 0 C for a time sufficient to achieve an acid number (see analytical section, below) of no greater than about 3.5;
  • step (c) cooling the product of step (b) to about 130 0 C;
  • step (d) optionally, adding to the product of step (c) additional caprolactone while maintaining the temperature at about
  • step (e) maintaining the temperature of the product of step (d) at about 130 0 C for 2 to 4 hours until a Gardner-Holdt viscosity [ASTM D1545 "Standard Test Method for Viscosity of Transparent Liquids by Bubble Time Method"] of Z to Z2
  • step (f) cooling the product of step (e) to 8O 0 C or lower;
  • step (g) adding to the product of step (f) at least one member of the group consisting of methacrylic acid, methacrylic anhydride, methacryloyl chloride, optionally in the presence of an aprotic organic solvent, while mixing at a temperature between about 23°C and about 100°C; and (h) isolating the reaction product of step (g).
  • Some aromatic solvents suitable for step (a) are toluene, benzene, p-xylene, m-xylene, o-xylene, and mixtures thereof.
  • Typical polyester polymerization catalysts that are useful in step (a) include, but are not limited to, Sn(2-ethylhexanoate) 2> Sn(n-octanoate)2 ; p- toluenesulfonic acid; and methanesulfonic acid. Tin(ll) catalysts are preferred.
  • aprotic organic solvents for suitable for step (g) are tetrahydrofuran ("THF"), diethyl ether, pyridine, N.N-dimethylacetamide, N,N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, CH 2 CI 2 , I
  • the reaction product is typically isolated in step (h) by either of two methods.
  • the first method involves an aqueous workup.
  • the organic phase is typically washed with an aqueous basic solution, such as saturated NaHCOs (aq), to remove acidic impurities. It may optionally be washed with dilute aqueous acidic solution (e.g., 10% HCI) to remove basic impurities such as pyridine. Then it is washed with saturated NaCI solution to remove the bulk of the water. It is optionally dried with a drying agent, such as MgSO 4 , to remove final traces of water. Then the organic solvent is removed, optionally under vacuum, to obtain the final product.
  • aqueous basic solution such as saturated NaHCOs (aq)
  • dilute aqueous acidic solution e.g., 10% HCI
  • a drying agent such as MgSO 4
  • a second method for isolating the product is to perform a high vacuum distillation directly on the reaction mixture. This is typically done at 0.5 torr (66 Pa) to distill off methacrylic acid and unreacted methacrylic anhydride. The second method typically is not used when methacryloyl chloride is used as the capping agent.
  • the present invention further provides an uncured dental composite material comprising: (a) at least one polymerizable (meth)acrylic ester component;
  • the compound of Formula I when present, could account for the entire (meth)acrylic ester content in the composite. However, this is not preferable because of its high viscosity. Therefore, it is preferred that the I compound of Formula I be used in combination with another polymerizable (meth)acrylic ester component having a lower viscosity than that of the Formula I material.
  • the relative amounts of the two materials will, of course, depend on the nature of the two materials. That ratio that provides the best overall balance of properties (shrinkage, flexural strength, and fracture toughness, etc.) may have to be determined experimentally. Generally speaking, however, a good balance of properties should be obtained when the material of Formula I is used at about 70 weight percent, based on the total weight of the (meth)acrylic ester component present in the composite material.
  • a particularly preferred uncured dental composite according to the present invention comprises a compound of Formula I as follows:
  • the compound of Formula I and the (meth)acrylated hyperbranched polyester polyol are used in a weight ratio of about 7/3. At this weight ratio, the high viscosity of the compound of Formula I is sufficiently reduced by the (meth)acrylated hyperbranched polyester polyol to allow fillers to be added and adequately mixed. The resulting material, when cured, shows relatively low shrinkage with good mechanical properties.
  • the (meth)acrylated hyperbranched polyester polyols of the present invention have sufficiently low viscosity to be used alone.
  • the relative amounts of the two materials will, of course, depend on the nature of the two materials. That ratio that provides the best overall balance of properties (shrinkage, flexural strength, and fracture toughness, etc.) may have to be determined experimentally.
  • the uncured dental composite can also comprise macromonomers that contain olefinic end groups.
  • macromonomers for use in the present invention are compounds of the Formula IV.
  • each Y is --COOR 17 , where the R 17 of each Y is independently selected from the group consisting of hydrogen, substituted or unsubstituted straight, branched, or cyclic alkyl having 1 to 20 carbon atoms, aryl, benzyl, and
  • Suitable macromonomers are dimers, trimers, tetramers, or higher oligomers of methyl, ethyl, propyl, butyl, 2-ethylhexyl, decyl, cyclohexyl, benzyl, glycidyl, hydroxyethyl, or hydroxypropyl methacrylate, methacrylic acid, or methacryloxypropyltrimethoxysilane.
  • the preferred macromonomer is the compound of Formula IV in which R 17 is methyl, and q is 1.
  • Macromonomers are most easily made by a metal chelate catalytic chain transfer, for example, using a cobalt chelate, as described in U. S.
  • Preferred uncured dental composite of the present invention is one that comprises at least one compound of Formula I with at least one macromonomer of Formula IV.
  • Formula IV act as a viscosity-lowering agent for the compound of Formula
  • the macromonomers of Formula IV function as chain transfer agents during the polymerization of the compounds of Formula I. More preferred are those compositions in which the compound of Formula I is
  • weight ratio of the preferred compound of Formula I to the preferred compound of Formula IV is 9/1. This ratio provides a workable, uncured composition (i.e., one that allows for the addition and mixing of fillers), which, upon curing, provides an extremely attractive balance of low shrinkage and excellent physical properties.
  • Another compound that may be used in addition to, or in place of, a compound of Formula I is a compound of Formula V.
  • R 1 , A, R 2 , R 3 are as defined in relation to the compound of Formula I, and each R 7 is independently selected from the group consisting of hydrogen, methyl, ethyl, C- 3 - 6 linear or branched alkyl, phenyl, benzyl, and the two R 7 groups may be taken together to form a substituted or unsubstituted cyclic aliphatic ring having 5 or 6 carbons in the ring, including the carbon to which both R 7 groups are attached.
  • Such compounds may be synthesized as shown below.
  • the polymerizable (meth)acrylic ester component may include, in addition to any of the following:
  • additional polymerizable (meth)acrylic ester compounds may include both monofunctional compounds and polyfunctional compounds, where "monofunctional” denotes a compound having one (meth)acrylic group and "polyfunctional” denotes a compound having more than one (meth)acrylic ester group.
  • monofunctional (meth)acrylic ester compounds include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, hydroxyethyl (meth)acryiate, benzyl (meth)acrylate, methoxyethyl (meth)acrylate, glycidyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, and the hydroxyethyl(meth)acrylate monoester of trimellitic anhydride.
  • polyfunctional (meth)acrylic ester compounds include di(meth)acrylates of ethylene glycol derivatives as represented by the general formula
  • R is hydrogen or methyl and n is an integer in a range of from 1 to 20, such as ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, and polyethylene glycol di(meth)acrylate.
  • polyfunctional (meth)acrylic ester compounds include, without limitation, Bis-GMA, EBPDMA, UDMA, and other urethane di(meth)acrylates.
  • Suitable polymerization initiator compounds include peroxy-type initiators such as benzoyl peroxide, dicumyl peroxide, lauryl peroxide, tributyl hydroperoxide, and other materials familiar to those skilled in the art.
  • activators may be advantageous in some formulations.
  • Suitable activators include, for example, N,N-bis-(hydroxyalkyl)-3,5- xylidines, N,N-bis-(hydroxyalkyl)-3,5-di-t-butylanilines, barbituric acids and their derivatives, and malonyl sulfamides.
  • Azo-type initiators such as 2,2'-azobis(isobutyronitrile), 2,2'- azobis(2,4-dimethyl valeronitrile), 2,2'-azobis(2-methyl butane nitrile), and 4,4'-azobis(4-cyanovaleric acid) may also be used.
  • photoinitiator systems include photosensitizers in combination with initiators.
  • Suitable photosensitizers include, for example, camphorquinone, benzoin ethers, ⁇ -hydroxyalkylphenones, acylphosphine oxides, ⁇ , ⁇ -dialoxyacetophenones, ⁇ -aminoalkylphenones, acyl phosphine sulfides, bis acyl phosphine oxides, phenylglyoxylates, benzophenones, thioxanthones, metallocenes, bisimidazoles, and ⁇ - diketones.
  • Photoinitiating initiators include, for example, ethyl dimethylaminobenzoate, dimethylaminoethyl methacrylate, dimethyl-p- toluidine, and dihydroxyethyl-p-toluidine.
  • Some materials are able to function as photoinitiators by themselves. Such materials include, for example, acylphosphine oxides.
  • Dental composites are typically cured with blue light in the 400-500 nm region.
  • a preferred photosensitizer is camphorquinone, used in conjunction with a tertiary amine like ethyl dimethylaminobenzoate or dimethylaminoethyl methacrylate.
  • the polymerization initiator (optionally with a photosensitizer) can be used in the range of about 0.1 weight percent to about 5 weight percent, preferably about 0.2 weight percent to about 3 weight percent, and more preferably about 0.2 weight percent to about 2 weight percent. The percentages are based on the total weight of the uncured dental composite, exclusive of filler. Fillers
  • inorganic fillers One class of fillers that may be used in the uncured dental composites of the present invention is inorganic fillers.
  • inorganic fillers are barium aluminum silicate, barium aluminum borosilicate, lithium aluminum silicate, strontium fluoride, lanthanum oxide, zirconium oxide, bismuth phosphate, calcium tungstate, barium tungstate, bismuth oxide, tantalum aluminosilicate glasses, and related materials. Glass beads, silica, quartz, borosilicates, alumina, alumina silicates, and other fillers may also be employed. Mixtures of inorganic fillers may also be employed.
  • the mean particle size of the inorganic fillers is preferably between about 0.5 and 15 ⁇ m, more preferably between 0.5 and 5 ⁇ m, most preferably between 0.5 and 2 ⁇ m.
  • Mean particles size may be determined, for example, by the use of a laser light diffraction particle size analyzer, such as those sold by Malvern Instruments, Malvern, U.K.
  • 15 ⁇ m can be combined with a second inorganic filler (of the same or different material) having a larger mean particle size in order to afford a workable composition with a total filler level higher than that obtainable by i the use of only the first inorganic filler.
  • the second inorganic filler preferably has a mean particle size that is at least about eight times the mean particle size of the first inorganic filler.
  • Submicron sized inorganic filler particles also can be used alone or in combination with the aforementioned inorganic fillers. Such particles can exist as individual particles or agglomerates of individual particles.
  • the term "submicron" is intended to denote that an individual particle has a mean particle size less than about 0.2 microns.
  • Preferred submicron sized inorganic fillers include such materials as fumed, pyrolytic, and colloidal silicas. Such silicas may be obtained, for example, from Degussa AG (Duesseldorf, Germany) under the trademark Aerosil ® OX-50.
  • Other submicron sized inorganic fillers may include alumina ortitania.
  • Inorganic filler particles that bear a hydroxyl group may be silanated prior to use in this invention. Silanation is well known to those skilled in the art, and any silanating compound may be used for this purpose. By “silanation” is meant chemical reaction by which some of the hydroxyl groups have been reacted with, for example, dimethyldichlorosilane to form a hydrophobic filler. The particles are typically from 50 to 95 percent silanated.
  • Silanating agents for inorganic fillers include, but are not limited to, ⁇ -mercaptoproyltrimethoxysilane, ⁇ -mercaptopropyltriethoxysilane, ⁇ - aminopropyltriethoxysilane, ⁇ -methacryloyloxypropyltrimethoxysilane, and ⁇ - methacryloyloxypropyltriethoxysilane.
  • organic fillers Another class of fillers that may be used in the uncured dental composites of the present invention is organic fillers.
  • Suitable organic fillers include prepolymerized fillers ("prepolymerized” in the sense that organic monomers have been polymerized to produce an organic resin, which, optionally, can be ground, prior to their inclusion in the uncured dental composites of this invention).
  • prepolymerized fillers may be included in the uncured dental composites of the invention alone or in combination with an inorganic filler. It is preferred that the prepolymerized fillers be used in combination with an inorganic filler.
  • Resins that could be used to make a prepolymerized filler include, but are not limited to, polymerized mono(meth)acrylic esters, polymerized poly(meth)acrylic esters, polymerized epoxy resins, polymerized unsaturated polyesters, polymerized vinyl ester resins, polymerized melamine-formaldehyde, and polymerized phenol-formaldehyde resins.
  • the preferred resins include those made from poly(meth)acrylate esters, particularly di- and tri- (meth)acrylate esters.
  • Uniformly-sized bead methacrylate polymers such as Plexidon ® or Plex ® available from Rohm America LLC (Piscataway, N.J.), also may be utilized as organic fillers.
  • Composite fillers are resins that incorporate an inorganic material.
  • the cured mixture can be comminuted to the desired particle size in suitable equipment, for example a grinder, ball mill, hammer mill, or vibratory mill. It may be sieved or classified to remove undesired fractions that have particle sizes that are too large or too small.
  • a preferred mean particle size range is from about 20 to about 100 microns.
  • Suitable organic monomers include, without limitation, monomers that are capable of polymerizing to provide polymerized mono(meth)acrylic esters, polymerized poly(meth)acrylic esters, polymerized epoxy resins, polymerized unsaturated polyesters, polymerized vinyl ester resins, polymerized melamine-formaldehyde, and polymerized phenol-formaldehyde.
  • the preferred monomers are poly(meth)acrylate esters, particularly di- and tri- (meth)acrylate esters.
  • Compounds of Formula I or Formula V or the (meth)acrylated hyperbranched polyester polyol of the present invention may be particularly useful.
  • Composite fillers may be used alone or in combination with inorganic fillers, the latter being preferred.
  • fillers e.g., inorganic with organic, inorganic with composite, organic with composite, or inorganic with both organic and composite.
  • the fillers may be desirable, for example, to combine fillers having a mean particle size of about 0.05 to 0.2 microns with fillers having a mean particle size of about 0.5 to 15 microns.
  • the former particle size fillers include, without limitation, fumed or colloidal silica.
  • filler sizes can be further combined with fillers having a mean particle size that is at least about eight times the mean particle size of the filler having a mean particle size between 0.5 and 15 microns, thereby providing a composition with high total filler level.
  • Using combinations of mixed particle size fillers may enable high total filler level, and this may, in turn, help to reduce polymerization shrinkage of the uncured dental composite, without sacrificing acceptable mechanical properties of the cured dental composite.
  • the total amount of filler in the uncured dental composites of the present invention can range from about 20 weight percent to about 90 weight percent, preferably from about 40 weight percent to about 90 weight percent, and more preferably from about 50 weight percent to about 85 weight percent. The percentages are based on the total weight of the uncured dental composite. Additional optional ingredients
  • the composite material may contain additional, optional ingredients. These may comprise activators, pigments, radiopaquing agents, stabilizers, antioxidants, and other materials.
  • Various combinations of pigments may be used to provide suitable color match with the surrounding tooth color.
  • Preferred radiopaquing agents include those substances that are suitable for providing radiopacity, thereby making the cured dental composites of this invention visible on conventional X-ray film.
  • Preferred stabilizers can include, for example, hydroquinone, hydroquinone monomethyl ether, 4-tert-butylcatechol, and 2,6-di-tert-butyl-4-methylphenol.
  • the uncured dental composite material of the present invention can be prepared using any mixing means known in the art. Such methods include, but are not limited to, roll mills, vibratory mixers, sigma mixers, planetary mixers, SpeedMixersTM (from Flack Tek, Inc., Landrum, South Carolina), extruders, Buss Kneaders (Coperion Holding GmbH, Stuttgart, Germany), and Brabender Plasticorders ® (Intellitorque, Brabender, hackensack, NJ). It is important to ensure homogeneous distribution of filler and prevent agglomeration of the finest particles that may be present.
  • the uncured dental composite material may be packaged in any container commonly used, such as a syringe or compule.
  • the dental composite materials of the present invention can be used to fill cavities in teeth. Other treatments may include preventative, restorative, or cosmetic procedures in teeth. Typically, without limiting the method to a specific order of steps, the dental composite materials are placed on dental tissue, either natural or synthetic, cured, and shaped as necessary to conform to the target dental tissue.
  • Dental tissue includes, but is not limited to, enamel, dentin, cementum, pulp, bone, and gingiva.
  • the dental composite materials may also be useful as dental adhesives, primers, bonding agents, pit and fissure sealants, cements, denture base and denture reline materials, orthodontic splint materials, and adhesives for orthodontic appliances.
  • the materials also may be useful for making bridges, crowns, inlays, onlays, laminate veneers, and facings.
  • the materials of the invention also may be useful for prosthetic replacement or repair of various hard body structures such as bone and also may be useful for reconstructive purposes during surgery, especially oral surgery.
  • THPE 1 ,1 ,1-tris(p-hydroxyphenyl) ethane
  • THPE GE 1 ,1 ,1-tris(p- hydroxyphenyl) ethane triglycidyl ether
  • Mono-2-(methacryloyloxy)ethyl succinate, mono-2-(methacryIoyloxy)ethyl maleate, and mono-2-(methacryloyloxy)ethyl phthalate were obtained from Aldrich Chemical Company (Milwaukee, Wisconsin).
  • Prostab ® 5415 was obtained from Ciba (Wilmington, Delaware). Tin (II) di-(2-ethylhexanoate), caprolactone, dimethylol propionic acid, pentaerythritol, n-propylamine (98%, catalogue # 109819), 3-
  • Triethylene glycol dimethacryiate (“TEGDMA”) was obtained from EssTech (Essington, Pennsylvania), product code product code X 943-7424, inhibited with hydroquinone (50-70 ppm).
  • Photosensitizers were obtained from Aldrich Chemical Company (Milwaukee, Wisconsin): camphorquinone (97%, catalogue #12,489-3) and ethyl 4- dimethylaminobenzoate (99+%, catalogue #E2, 490-5).
  • Aerosil ® OX-50 fumed silica was obtained from Degussa (Dusseldorf, Germany).
  • Schott 8235 UF1.5 glass powder was obtained from Schott AG (Mainz, Germany); it had a mean diameter, d50, of 1.5 ⁇ m and was treated with C-I 0 H 2O O 5 Si to a level of 2.3 wt% silane.
  • Uncured compositions intended for testing were packed into a stainless steel 2mm thick mold with at least one 2 mm x 25 mm opening to enable two sides of the uncured composition to be exposed.
  • the packed mold was sandwiched on either side with a polyester film, followed a glass plate.
  • a bar of each uncured composition was cured for 60 sec. per side at 550 mW/cm 2 .
  • DSC Differential Scanning Calorimetry
  • the degree of monomer polymerization (“conversion") was measured by Fourier Transform Infrared (FTIR) spectroscopy, using the total attenuated reflectance (ATR) method.
  • FTIR Fourier Transform Infrared
  • ATR total attenuated reflectance
  • the DC is referred to as the "C-Peak” degree of conversion.
  • the so-called “E-Peak” degree of conversion was also measured as described in Dental Materials (1990), 6(4), 241-249.
  • This alternative method uses the ratio of the 1640 cm ⁇ 1 and the 1580 crrH peaks, rather than the 1640 cnr ⁇ and 1610 cm” 1 peaks.
  • the baseline of the 1640 cm”1 peak is defined by drawing a baseline from the value at 1660 cm-1 to the value at about 1590 cm ⁇ 1.
  • the percent methacrylation of the hyperbranched polyester polyol was measured by 1 H NMR and IR spectroscopy. This method for measuring percent methacrylation has been described in, for example, Culbertson (J. Macromol. ScL Pure Appl. Chem. (2002), A39(4), 267-286), and uses the absence of the O-H stretch near 3500 cm "1 to indicate a fully methacrylated polyol. This method was employed in combination with 1 H NMR spectroscopy in the examples that follow. A fully methacrylated j polyol was prepared using an excess of methacrylating agent. The fully methacrylated polyol was analyzed using 1 H NMR spectroscopy.
  • the area under the peak corresponding to the allylic CH 3 of the methacrylate group at 1.8 ppm (DMSO-d 6 ) was determined.
  • the area of under the peak corresponding to the caprolactone alpha CH 2 group at 2.2 ppm also was determined.
  • a ratio, Y, characteristic of the fully methacrylated product is defined as:
  • a new ratio, X, characteristic of the partially methacrylated product is defined as:
  • the % methacrylation is then defined as:
  • % methacrylation (X / Y) x 100.
  • the acid number was determined as follows. The substance to be tested was dissolved in a suitable neutral solvent. The resulting solution was titrated with standard potassium hydroxide solution to a phenolphthalein or thymolphthalein endpoint. The acid number is expressed as the number of milligrams of potassium hydroxide required to neutralize one gram of the substance.
  • Fracture toughness (Kic), flexural strength (ISO 4049), and density were determined on (2 mm x 2 mm x 25 mm) bars that were molded using the stainless steel mold described above.
  • the molded bars were cured in the mold by irradiating each exposed side for 1 minute using either a) an array of three Dentsply Spectrum 800 dental lamps at 550 mW/cm 2 , or b) a Fusion UV Systems curing unit equipped with a Q-bulb (designed for emitting light at a wavelength suitable for camphorquinone excitation).
  • the metal mold was covered on both sides with a 3-mil (76-micron) polyester film to exclude oxygen.
  • the fracture toughness test was based on both the ASTM polymers standard (ASTM D5045) and the ASTM ceramics standard (ASTM C1421 , precracked beam method). Testing was conducted at a test speed of 0.5 mm/min at room temperature and ambient humidity using a three-point bend fixture (span to depth ratio of 10). The specimens were molded using the flex bar mold specified in ISO 4049. The specimens were precracked halfway through their depth. Two modifications to the test procedures were made. The first was the use of smaller test specimens than those recommended in the ASTM C1421 standard (2 mm x 2 mm x 25 mm instead of the recommended minimum dimensions of 3 mm x 4 mm x 20 mm).
  • the second was the use of a slitting circular knife to machine the precracks.
  • the knife was 0.31 mm in thickness with a 9 ° single bevel.
  • the modified test procedures produced precracks that were equivalent to precracks produced using the techniques recommended in ASTM D5045.
  • the percent shrinkage (%S) was determined by measuring the densities of uncured dental composites and of bars of cured dental composites. The densities were measured with an AccuPyc 1330 Helium Pycnometer (Micromeritics Instrument Corporation, Norcross, Georgia). An uncured mixture of dental composite was placed in a PTFE mold having a 2 mm depth into which a 4 x 25 mm opening was made, thereby exposing two sides of a bar of the uncured dental composite. The mold was covered on either side with both a polyester sheet, followed by a glass plate. Three dental curing lamps (model Spectrum 800 from Dentsply, set at a visible light intensity of 550 mW/cm 2 ), were aligned above and parallel to the length of the bar. Each bar was cured for 2 min on its first side and then 2 min on its second side. i
  • the density of the uncured dental composite was determined by measuring the volume of a known weight of composite. Briefly, the pycnometer was set up for 10 purges and 5 volume measurements per sample. The pycnometer cell had a volume of 1 cubic centimeter. For the uncured composite material, a liner made from aluminum foil was used to prevent the composite adhering to the cup of the pycnometer. The volume of the aluminum foil was subtracted from the volume of the uncured dental composite. The density of uncured composite puncured is defined as grams of uncured composite divided by volume of uncured composite in cubic centimeters.
  • the density of the cured dental composite was measured in a similar manner as described above, except that an aluminum foil liner was not used.
  • the density of uncured composite p cured is defined as grams of cured composite divided by volume of cured composite in cubic centimeters.
  • the composite was applied to 700 mL silica in a 2L coarse frit funnel and eluted with 1L hexanes, 3L 4/1 hexanes/EtOAc, 2L 2/1 hexanes/EtOAc, 2L 1/1 hexanes/EtOAc, and 2L EtOAc.
  • the fractions at Rf 0.33 (silica gel, 1/1 hexanes/EtOAc) were collected and concentrated in vacuo to give 52.6g (47%) of the product as a pale orange oil.
  • R 2 is -CRH 4 -, each R 3 is H, R 7 is methyl, and A is -[Q-R 6 In- where R 6 is
  • THPE GE Phthalate HEMA 1
  • THPE PO MA was synthesized according to the method of B. Culbertson et al., J. Macromol. Sci. Pure Appl. Chem. (2002), A39(4), 251- 265.
  • the contents were mixed for three 30-second intervals at 3000 rpm. After a brief cooling period (10 minutes), the contents were mixed for an additional 30 s at 3000 rpm. The resulting paste was stored refrigerated in a yellow light room to prevent premature curing.
  • EXAMPLE 14 Synthesis of a (meth)acrylated hyperbranched polyester methacrylate using methacrylic anhydride as an end capping agent for a hyperbranched polyester polyol made in a single stage reaction A.
  • the mixture was heated at 180 0 C and the reaction progress was monitored by measurement of acid number and the volume of water collected. After 8.5 hr, about 72 ml_ water was collected. A 1 g sample was withdrawn and dissolved in 10 ml_ DMSO. The acid number was determined to be 2.0 by titration with 0.1 M KOH in methanol. The heating temperature was reduced to 120 0 C and cyclohexene oxide (40 g, 0.41 mol) was added. After 60 min, the acid number was determined to be 1.5. The heating was continued for 2.5 hours under a vacuum of about 30 torr. The heating temperature was increased to 180 0 C and held for 5 hours under reduced pressure ( ⁇ 1 torr).
  • the hot, viscous, clear polymer was poured out of the reactor to a glass jar.
  • the acid number was determined to be 1.1.
  • the Tg was determined by differential scanning calorimetry to be -26°C.
  • a 100 gallon reactor was charged with caprolactone (171 kg), tin(ll) octanoate (1.27 kg), pentaerythritol (3.4 kg), DMP (85.5 kg), xylenes (13 kg), and heated to 69-71 0 C until a solution was obtained. The solution was then heated to 17O 0 C with vigorous stirring and water was collected overhead until the solution reached an acid number of 3.5. The temperature was not allowed to exceed 200 0 C. The mixture was allowed to cool to about 25 0 C and then discharged in to a barrel to obtain the desired product as a colorless, transparent, viscous liguid.
  • the solution was cooled to 129-131 0 C.
  • Caprolactone (156 kg) was added to the solution with stirring over 30 minutes. The mixture may exotherm up to about 14O 0 C during the feed. The solution was held at 129-131 0 C for two hours. The mixture was then discharged in to a barrel to obtain the desired product as a colorless, transparent, viscous liquid.
  • the hyperbranched polyester polyol of example 16 was used to prepare the following partially (meth)acrylated hyperbranched polyester polyol:
  • IR spectroscopy of the neat sample showed reduced OH-stretching relative to the starting polyol, with a band centered at 3538 cm "1 . Additionally, a strong ester peak at 1730 cm '1 and a peak at 1637 cm '1 representing the methacrylate double bond were noted in the IR spectrum. 1 H NMR spectroscopy (in CDCI 3 ) confirmed the presence of terminal OH and terminal methacrylate groups, with a methacrylate capping level near 62%.
  • EXAMPLE 21 Synthesis of a hyperbranched polyester methacrylate by capping a hyperbranched polyester polvol with methacrylic anhydride (38% capped, hereinafter "2X 38% MA"
  • a mixture of the hyperbranched polyester polyol of Example 16 (126 g, 0.653 mol of reactive OH), methacrylic anhydride (33 g, 0.21 mol) and pyridine (17 g, 0.21 mol) was heated to 110 0 C for 4.5 hours under a dry air stream.
  • the reaction mixture was cooled to room temperature and then slowly poured into a solution of 10% sodium carbonate (300 ml_).
  • the resulting mixture was stirred for two hours, diluted with ethyl acetate (500 ml_) and then gently stirred overnight. The mixture was transferred to a separatory funnel and the aqueous layer (containing an emulsion enriched in OH-terminated product) was discarded. The remaining organic layer was washed with 5% HCI (3 x 100 ml_) and water (2 x 100 ml_) and was then dried over anhydrous sodium carbonate. After filtering, the resulting solution was treated with MEHQ (50 mg) and then concentrated in vacuo with mild heating, giving a clear viscous oil. The oil, kept at room temperature, was further concentrated by applying a vacuum of 20 mm Hg (with filtered air-bleed) for an additional 4 h period, followed by high vacuum for 12 hours, ultimately furnishing 74 g of the product.
  • MEHQ 50 mg
  • IR spectroscopy of the neat sample showed significantly reduced OH-stretching relative to the starting polyol, with a band centered at 3524 cm "1 . Additionally, a strong ester peak at 1730 cm '1 and a peak at 1637 cm '1 representing the methacrylate double bond were noted in the IR spectrum. 1 H NMR spectroscopy (in CDCI 3 ) confirmed the presence of terminal OH and terminal methacrylate groups, with a methacrylate capping level near 38%.
  • EXAMPLE 22 Synthesis of a hyperbranched polyester methacrylate by capping a hyperbranched polyester polyol with methacrylic anhydride and acetic anhydride (62% capped with methacrylate, 38% capped with acetate, hereinafter "2X 62% MA 38% Ac")
  • a mixture of the partially methacrylated polyester polyol prepared in Example 20 (44 g, ca. 0.19 mol of reactive OH), acetic anhydride (22 g, 0..22 mol) and pyridine (17 g, 0.21 mol) was heated to 110 0 C for 4 hours under a dry air stream.
  • the reaction mixture was cooled to room temperature and then slowly poured into a solution of 10% sodium carbonate (200 ml_).
  • the resulting mixture was stirred for one hour, diluted with diethyl ether (300 ml_) and then gently stirred overnight.
  • the mixture was transferred to a separatory funnel and the aqueous layer was discarded.
  • the remaining organic layer was washed with 5% HCI (3 x 100 ml_) and water (2 x 100 ml_) and was then dried over anhydrous sodium carbonate. After filtering, the resulting solution was treated with MEHQ (20 mg) and then concentrated in vacuo with mild heating, giving a viscous, light-orange oil. The oil, kept at room temperature, was further concentrated by applying a vacuum of 20 mm Hg (with filtered air-bleed) for an additional 4 h period, followed by high vacuum for 12 hours, ultimately furnishing 30 g of the product.
  • IR spectroscopy of the neat sample showed a near absence of OH- stretching relative to the partially methacrylated starting material. Additionally, a broad ester peak centered at 1736 cm '1 and a peak at 1637 cm "1 representing the methacrylate double bond were noted in the IR spectrum. 1 H NMR spectroscopy (in CDCI 3 ) confirmed the presence of terminal acetate groups and terminal methacrylate groups, with a methacrylate capping level near 60%.
  • EXAMPLE 23 (Comparative). Synthesis of Perstorp Boltorn H2004 Methacrylate (hereinafter "Comp 23”) A mixture of Boltorn H2004 polyol (obtained from Perstorp Specialty Chemicals AB, Sweden) (83 g, 0.44 mol of reactive OH), methacrylic anhydride (73 g, 0.47 mol) and pyridine (37 g, 0.47 mol) was heated to 110 0 C for 4.5 hours under a dry air stream. The reaction mixture was cooled to room temperature and then slowly poured into a solution of 10% sodium carbonate (300 ml_). The resulting mixture was extracted with diethyl ether (3 x 100 ml_).
  • the ether extracts were combined and then washed with 5% HCI (3 x 100 ml_), water (3 x 50 mL). And then brine (50 ml_).
  • the ether solution was next dried over anhydrous sodium carbonate. After filtering, the resulting solution was treated with MEHQ (40 mg) and then concentrated in vacuo, giving a clear, viscous oil.
  • the oil kept at room temperature, was further concentrated by applying a vacuum of 20 mm Hg (with filtered air-bleed) for an additional 4 h period, followed by high vacuum for 1 hour, ultimately furnishing 66 g of the product.
  • IR spectroscopy of the neat sample showed an absence of OH- stretching at 3522 cm “1 relative to the starting polyol. Additionally, a strong ester peak at 1741 cm “1 and a peak at 1638 cm '1 representing the methacrylate double bond were noted in the IR spectrum.
  • the polymerizable (meth)acrylic ester component was made up of a first component, which was either Bis-GMA, THPE GE MA, or THPE PO MA; and a second component, here, either Comp 23 or 2X 96% MA.
  • the ingredients were mixed in a Flack Tek SpeedMixerTM as described in Examples 7-13. Except for the materials of Example 28(Comp.) and 29, which were too viscous to process, the paste was formed into bars, cured, and tested as described above. Results are presented in Table 2, in which "Ex” denotes "Example”. 2X 96% MA- containing composites had higher toughness, flexural strength, and comparable shrinkage as compared to the composites made with the material of Comp 23.
  • the polymerizable (meth)acrylic ester component was made up of a first component, which was either THPE GE Succinate HEMA, or THPE GE Succinate HEMA Ac; and a second component, a methacrylated hyperbranched polyester reaction product of the current invention.
  • the composites of Table 3 were hand mixed. Briefly, the components were combined in a beaker, cast on to a PTFE sheet and kneaded for several minutes. The kneading process involves flattening the composite, folded it over, and then flattening it again.
  • the mixtures were degassed in a desiccator with vacuum pump, cycling between atmospheric pressure and full vacuum every 10 min. for 1 hour, then holding at 50 torr overnight (about 16 hr).
  • the mixtures were further degassed for 8 hr at 45°C in a vacuum oven at 380 torr of vacuum, with an air flow to prevent premature polymerization.
  • the mixtures were wrapped in foil to exclude light and stored in a refrigerator until used.
  • Table 3 shows that compounds of Formula I, combined with a (meth)acrylated hyperbranched polyester polyol of the present invention in a 50/50 ratio, based on the total weight of polymerizable (meth)acrylic ester component, provide a good balance of physical properties and low shrinkage.
  • a Sigma mixer (“B&P Model 2 cubic inch Horizontal Batch Mixer", B&P Process Equipment and Systems LLC, 1000 Hess Ave., Saginaw, Michigan, USA) was used to prepare the dental composites in examples 34 to 42.
  • the procedure for preparing dental composites in a sigma mixer is as follows.
  • the monomers, photosensitizers, and fillers were combined in a glass vessel and then transferred to the Sigma mixer that was preheated to 45°C.
  • the sample was mixed for 15 minutes at 10 rpm at atmospheric pressure, 15 minutes at 20 rpm at atmospheric pressure, and 30 minutes at 15 rpm under a vacuum of 245 torn Bars were prepared from the uncured composite, cured with visible light, and tested as previously described. Results are presented in Table 4.
  • Table 4 shows that the use of a lower percentage of the compound of Formula I, while providing low shrinkage, provides composites with less than optimal mechanical properties. Table 4 also shows that increasing the amount of compound of Formula I to 70 percent provides materials having reasonable shrinkage with improved mechanical properties. The best example in Table 4 is Example 37, which provided the best balance of low shrinkage with optimal mechanical properties.
  • MMA dimer The synthesis of the MMA dimer was described in Macromolecules (1996), 29, 7717.
  • Dental composites were prepared using the same procedure as described in Examples 7-13.
  • monomers were selected from either Bis-GMA or a compound of Formula I, namely THPE GE Su HEMA.
  • monomers were selected from either the MMA dimer or TEGDMA.
  • the uncured composite was formed into bars, cured using visible light, and tested as described above. Results are presented in Table 5.
  • Table 5 shows that the MMA dimer can be used instead of TEGDMA. If the MMA dimer is used in high loadings, it will result in reduced polymerization shrinkage (compare example 45 with example 47, and also example 46 with 48), but the flexural strength and fracture toughness will be reduced (compare example 46 with 48). However, at low MMA dimer loadings (example 44) a good balance of low polymerization shrinkage and high flexural strength and high fracture toughness is achieved.
  • EXAMPLES 49 (Comparative) and 50 Dental composite materials made with one polvmerizable component
  • Dental composites were prepared using the same procedure as described in Examples 7-13.
  • the monomer was selected from either Bis-GMA or a compound of structure I, namely, THPE GE Su HEMA.
  • Table 6 shows that a composite made from a compound of Formula
PCT/US2005/032940 2004-09-14 2005-09-14 Materials leading to dental composites WO2006031971A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US60958804P 2004-09-14 2004-09-14
US60/609,588 2004-09-14

Publications (1)

Publication Number Publication Date
WO2006031971A1 true WO2006031971A1 (en) 2006-03-23

Family

ID=35466097

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2005/032940 WO2006031971A1 (en) 2004-09-14 2005-09-14 Materials leading to dental composites

Country Status (2)

Country Link
US (1) US7541392B2 (US07541392-20090602-C00008.png)
WO (1) WO2006031971A1 (US07541392-20090602-C00008.png)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006124655A1 (en) * 2005-05-13 2006-11-23 E. I. Du Pont De Nemours And Company Materials and dental composites made therefrom
WO2006124656A1 (en) * 2005-05-13 2006-11-23 E. I. Du Pont De Nemours And Company Materials and dental composites made therefrom
US7530812B2 (en) 2006-07-11 2009-05-12 Chyz Grant T Three-dimensional dental training system
WO2012152741A1 (de) 2011-05-10 2012-11-15 Bayer Intellectual Property Gmbh Bicyclische (thio)carbonylamidine

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060058415A1 (en) * 2004-09-14 2006-03-16 Arthur Samuel D Materials leading to improved dental composites and dental composites made therefrom
US20060058416A1 (en) * 2004-09-14 2006-03-16 Brandenburg Charles J Materials leading to improved dental composites and dental composites made therefrom
DE102005021332B4 (de) * 2005-05-04 2008-02-28 Heraeus Kulzer Gmbh Kompositmaterialien mit geringer Schrumpfkraft
US9289358B2 (en) * 2007-02-28 2016-03-22 Ultradent Products, Inc. Resin reinforced zinc polycarboxylate temporary cement compositions and related kits and methods
US8568888B2 (en) 2007-03-15 2013-10-29 Nanovere Technologies, Inc. Dendritic polyurethane coating
US8206827B2 (en) * 2007-03-15 2012-06-26 Nanovere Technologies, Llc Dendritic polyurethane coating
CA2963857A1 (en) * 2007-06-04 2008-12-11 Ben-Gurion University Of The Negev Research And Development Authority Tri-aryl compounds and compositions comprising the same
WO2009129359A2 (en) * 2008-04-18 2009-10-22 3M Innovative Properties Company Dental filling composition comprising hyperbranched compound
CN102295838B (zh) * 2011-07-06 2014-10-08 浙江大学 一种六枝状偶氮硅氧烷染料及其合成方法
JP6615549B2 (ja) * 2015-09-17 2019-12-04 株式会社松風 歯科用硬化性組成物
US20230091071A1 (en) * 2020-02-10 2023-03-23 Kuraray Noritake Dental Inc. Resin composition for stereolithography

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4338242A (en) * 1980-09-19 1982-07-06 The Dow Chemical Company Urethane modified polymers having hydroxyl groups
WO2000077070A2 (en) * 1999-06-09 2000-12-21 Ucb, S.A. Modified hyperbranched polyester polymers, processes for preparing them and uses of them
WO2001046296A1 (en) * 1999-12-22 2001-06-28 Basf Corporation Hyperbranched polyol macromolecule, method of making same, and coating composition including same

Family Cites Families (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3367992A (en) 1964-06-05 1968-02-06 Dow Chemical Co 2-hydroxyalkyl acrylate and methacrylate dicarboxylic acid partial esters and the oxyalkylated derivatives thereof
JPS62161742A (ja) 1986-01-08 1987-07-17 Nippon Paint Co Ltd 末端カルボキシル基を有する反応性アクリル単量体ならびにその製法
SE9200564L (sv) * 1992-02-26 1993-03-15 Perstorp Ab Dendritisk makromolekyl av polyestertyp, foerfarande foer framstaellning daerav samt anvaendning daerav
US5264530A (en) 1992-05-01 1993-11-23 E. I. Du Pont De Nemours And Company Process of polymerization in an aqueous system
CA2103400C (en) * 1992-11-19 1998-08-25 Andrew T. C. Liu Abrasion resistant dental composition product and process
SE503559C2 (sv) * 1994-09-08 1996-07-08 Inst Polymerutveckling Ab Strålningshärdbar hypergrenad polyester, förfarande för dess framställning samt dess användning
US6316519B1 (en) * 1997-02-19 2001-11-13 E. I. Du Pont De Nemours And Company Molecular weight controlled polymers by photopolymerization
US6348518B1 (en) * 1997-12-10 2002-02-19 R. Eric Montgomery Compositions for making an artificial prosthesis
FI20010222A0 (fi) * 2001-02-06 2001-02-06 Yli Urpo Antti Lääketieteellisesti hammashoidolliset polymeerikomposiitit ja -koostumukset
US6787629B2 (en) * 2001-11-02 2004-09-07 Pentron Clinical Technologies, Llc Dental resin materials, method of manufacture, and uses thereof
US7241856B2 (en) * 2003-06-02 2007-07-10 Pentron Clinical Technologies Llc Dental resins, dental composite materials, and method of manufacture thereof
US6890968B2 (en) * 2001-05-16 2005-05-10 Kerr Corporation Prepolymerized filler in dental restorative composite
NZ535106A (en) * 2002-02-20 2006-06-30 Robert John Barsotti Lacquers containing highly branched copolyester polyol
TWI281923B (en) * 2002-11-26 2007-06-01 Dainippon Ink & Chemicals Process for producing polymerizable hyperbranched polyester
US20050124762A1 (en) * 2003-12-03 2005-06-09 Cohen Gordon M. Dental compositions containing core-shell polymers with low modulus cores
US20060058416A1 (en) * 2004-09-14 2006-03-16 Brandenburg Charles J Materials leading to improved dental composites and dental composites made therefrom
US7560500B2 (en) * 2005-05-13 2009-07-14 E. I. Du Pont De Nemours And Company Materials leading to improved dental composites and dental composites made therefrom

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4338242A (en) * 1980-09-19 1982-07-06 The Dow Chemical Company Urethane modified polymers having hydroxyl groups
WO2000077070A2 (en) * 1999-06-09 2000-12-21 Ucb, S.A. Modified hyperbranched polyester polymers, processes for preparing them and uses of them
WO2001046296A1 (en) * 1999-12-22 2001-06-28 Basf Corporation Hyperbranched polyol macromolecule, method of making same, and coating composition including same

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
CHUNG C -M ; KIM J -G ; KIM M -S ; KIM K -M ; KIM K -N: "Development of a new photocurable composite resin with reduced curing shrinkage", DENTAL MATERIALS, vol. 18, no. 2, 2002, pages 174 - 178, XP002356540 *
CHUNG CHAN-MOON; KIM MIN-SUNG; KIM JOONG-GON; JANG DOO-OK: "Synthesis and photopolymerization of trifunctional methacrylates and their application as dental monomers", JOURNAL OF BIOMEDICAL MATERIALS RESEARCH, vol. 62, no. 4, 2002, pages 622 - 627, XP002356539 *
KIM J-G ET AL: "Trifunctional methacrylate monomers and their photocured composites with reduced curing shrinkage, water sorption, and water solubility", BIOMATERIALS, ELSEVIER SCIENCE PUBLISHERS BV., BARKING, GB, vol. 24, no. 21, September 2003 (2003-09-01), pages 3845 - 3851, XP004431165, ISSN: 0142-9612 *
WAN, QICHUN; SCHRICKER, SCOTT, R; CULBERTSON, BILL M: "Hyperbranched multi-methacrylates: their application in dental resin systems", POLYMER PREPRINTS - AMERICAN CHEMICAL SOCIETY, POLYMER PREPRINTS, DIVISION OF POLYMER CHEMISTRY, vol. 41, no. 1, 2000, pages 155 - 156, XP008057920 *

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006124655A1 (en) * 2005-05-13 2006-11-23 E. I. Du Pont De Nemours And Company Materials and dental composites made therefrom
WO2006124656A1 (en) * 2005-05-13 2006-11-23 E. I. Du Pont De Nemours And Company Materials and dental composites made therefrom
US7560500B2 (en) 2005-05-13 2009-07-14 E. I. Du Pont De Nemours And Company Materials leading to improved dental composites and dental composites made therefrom
US8084514B2 (en) 2005-05-13 2011-12-27 E. I. Du Pont De Nemours And Company Materials leading to improved dental composites and dental composites made therefrom
US7530812B2 (en) 2006-07-11 2009-05-12 Chyz Grant T Three-dimensional dental training system
WO2012152741A1 (de) 2011-05-10 2012-11-15 Bayer Intellectual Property Gmbh Bicyclische (thio)carbonylamidine

Also Published As

Publication number Publication date
US7541392B2 (en) 2009-06-02
US20060058414A1 (en) 2006-03-16

Similar Documents

Publication Publication Date Title
US7541392B2 (en) Materials leading to improved dental composites and dental composites made therefrom
WO2006031972A1 (en) Materials leading to dental composites
EP0861230B1 (en) Liquid crystalline (meth)acrylate compounds, composition and method
WO2006031970A1 (en) Tri (meth) acrylate-based dendrimers as base monomers for materials leading to improved dental composites and dental composites made therefrom
WO2006031967A1 (en) Materials leading to dental composites
EP1879544B1 (en) Materials and dental composites made therefrom
WO2006031968A1 (en) Materials leading to dental composites
WO2005055961A1 (en) Dental compositions containing core-shell polymers with low modulus cores
CA2893417A1 (en) Polysiloxane compound and dental materials prepared therefrom
JP5216343B2 (ja) 歯科材料に好適な重合性単量体
JP6599346B2 (ja) 歯科用組成物及びその使用
US20050124721A1 (en) Bulky monomers leading to resins exhibiting low polymerization shrinkage
US20100240794A1 (en) Dental resin composition, method of manufacture, and method of use thereof
WO2006124656A1 (en) Materials and dental composites made therefrom
WO2005056623A1 (en) Dental compositions containing liquids and other elastomers
US20050124722A1 (en) Branched highly-functional monomers exhibiting low polymerization shrinkage
US7495038B2 (en) Materials leading to improved dental composites and dental composites made therefrom
EP2881103B1 (en) Dental composition
CN113292594A (zh) 长波吸收光引发剂
EP4085893A1 (de) Transparente, bruchzähe polymerisationsharze zur herstellung dentaler formkörper

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KM KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NA NG NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SM SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): BW GH GM KE LS MW MZ NA SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LT LU LV MC NL PL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase