Carbosiloxane dendrimers

Abstract: The present invention relates to a carbosiloxane dendrimer that contains at least one siloxane unit with the general formula X 1 R 1 a SiO (3-a)/2 wherein R 1 is C 1 to C 10 alkyl or aryl, a is an integer from 0 to 2, and X 1 is the silylalkyl group with the following formula at i = 1 where R 1 is C 1 to C 10 alkyl or aryl, R 2 is C 2 to C 10 alkylene, R 3 is C 1 to C 10 alkyl, X i + 1 is the above-defined silylalkyl group at i = i + 1 , an unsubstituted monovalent hydrocarbon group, a monovalent hydrocarbon group substituted by an atom other than a carbon or hydrogen atom, or a monovalent hydrocarbon group substituted by a group containing an atom other than a carbon or hydrogen atom, i is an integer with a value from 1 to 10 that specifies the generation of said silylalkyl group, and b i is an integer from 0 to 3 with the proviso that b 1 in at least one X 1 in each molecule is an integer from 0 to 2, and which has at least one siloxy group represented by the general formula: wherein R1 is a C1 to C10 alkyl or aryl group, and R4 is a monovalent unsubstituted hydrocarbon group, a monovalent hydrocarbon group substituted by an atom other than a carbon or hydrogen atom, or a monovalent hydrocarbon group substituted by a group containing an atom other than a carbon or hydrogen atom and wherein when more than 1 siloxane unit is present the subject siloxane units is the same or different.

Description: This invention relates to a novel carbosiloxane dendrimer that has a highly branched structure in which the siloxane bond and silalkylene bond alternate, that contains at least one substituted or unsubstituted hydrocarbon group at a terminal position, that can also be prepared in a high-molecular-weight form, and that exhibits a narrow molecular weight distribution and to a process for its production. Dendrimers are polymers with a narrow molecular weight distribution that have a highly branched structure which elaborates radially from a single core. Dendrimers are characterized by a low viscosity, high reactivity, high solubility, and low glass-transition temperature and as a consequence their applications have been the subject of study. The following are examples of the already known organosilicon dendrimers: siloxane dendrimers (refer to Rebrov et al., Dokl. Acad. Nauk. SSSR , 309, 367 (1989) and Masamune et al., J. Am. Chem. Soc. , 112, 7077 (1990)), carbosiloxane dendrimers (refer to Kakimoto et al., Macromolecules , 24, 3469 (1991); Japanese Published Patent Application (Kokoku or Examined) Number Hei 7-17981 (17,981/1995); and Sheiko et al., Macromol. Rapid Commun ., 17, 283 (1996)), and carbosilane dendrimers (refer to Roovers et al., Macromolecules , 26, 963 (1993) and Japanese Published Patent Application (Kokoku or Examined) Number Hei 8-311205 (311,205/1996)). This literature also discloses carbosiloxane dendrimers in which the siloxane bond and silalkylene bond occur in alternation (refer to Japanese Published Patent Application (Kokoku or Examined) Number Hei 7-17981 and Sheiko et al., Macromol. Rapid Commun. , 17, 283 (1996)). However, the carbosiloxane dendrimers disclosed therein are limited to dendrimers in which the starting reagent that forms the dendrimer core is a silane compound bearing a plural number of vinyl or allyl groups bonded to a single silicon atom, and the methods disclosed therein can only produce low-molecular-weight dendrimer at a low number of generations. The synthesis by a one-step polymerization method of highly branched polymer in which the siloxane bond and silalkylene bond alternate has also been disclosed (refer to Mathias et al., J. Am. Chem. Soc. , 113, 4043 (1991)), but this method cannot produce dendrimer with a narrow molecular weight distribution. In sum, then, there has yet to appear carbosiloxane dendrimer that has a highly branched structure in which the siloxane bond and silalkylene bond alternate, that can also be prepared in a high-molecular-weight form, and that exhibits a narrow molecular weight distribution and that preferably has subsituents. The present inventors developed the present invention as a result of extensive investigations directed to solving the problems described above. In specific terms, the object of the present invention is to provide a novel carbosiloxane dendrimer that has a highly branched structure in which the siloxane bond and silalkylene bond alternate and having preferably subsituents. SUMMARY OF THE INVENTION The present invention relates to a carbosiloxane dendrimer that contains at least one siloxane unit with the general formula X 1 R 1 a SiO (3-a)/2 where R 1 is C 1 to C 10 alkyl or aryl, a is an integer from 0 to 2, and X 1 is the silylalkyl group with the following formula at i = 1 where R 1 is C 1 to C 10 alkyl or aryl , R 2 is C 2 to C 10 alkylene, R 3 is C 1 to C 10 alkyl, X i+1 is the above-defined silylalkyl group at i = i + 1 , an unsubstituted monovalent hydrocarbon group, a monovalent hydrocarbon group substituted by an atom other than a carbon or hydrogen atom, or a monovalent hydrocarbon group substituted by a group containing an atom other than a carbon or hydrogen atom, i is an integer with a value from 1 to 10 that specifies the generation of said silylalkyl group, and b i is an integer from 0 to 3 with the proviso that b 1 in at least one X 1 in each molecule is an integer from 0 to 2, and which has at least one siloxy group represented by the general formula: wherein R1 is a C 1 to C 10 alkyl or aryl group, and R 4 is a monovalent unsubstituted hydrocarbon group, a monovalent hydrocarbon group substituted by an atom other than a carbon or hydrogen atom, or a monovalent hydrocarbon group substituted by a group containing an atom other than a carbon or hydrogen atom and wherein when more than 1 siloxane unit is present the subject siloxane units may be the same or different. Preferably the carbosiloxane dendrimer comprises a polysiloxane structure that contains at least 2 silicon atoms as a core and at least one of the aforesaid siloxane units. DETAILED DESCRIPTION OF THE INVENTION The carbosiloxane dendrimer according to the present invention characteristically has a polysiloxane structure that contains at least one siloxane unit with the general formula X 1 R 1 a SiO (3-a)/2 wherein when more than 1 siloxane unit is present the subject siloxane units may be the same or different. R 1 in this general formula is C 1 to C 10 alkyl or aryl. The alkyl encompassed by R 1 can be exemplified by methyl, ethyl, propyl, butyl, pentyl, isopropyl, isobutyl, cyclopentyl, and cyclohexyl, while the aryl encompassed by R 1 can be exemplified by phenyl and naphthyl. Methyl is preferred among the preceding. The subscript a is an integer with a value from 0 to 2. X 1 is the silylalkyl group with the following formula at i = 1 R 1 in this general formula is defined as above. R 2 in the preceding general formula is C 2 to C 10 alkylene, for example, straight-chain alkylene such as ethylene, propylene, butylene, and hexylene and branched alkylene such as methylmethylene, methylethylene, 1-methylpentylene, and 1,4-dimethylbutylene. Ethylene, methylmethylene, hexylene, 1-methylpentylene, and 1,4-dimethylbutylene are preferred for R 2 . R 3 is C 1 to C 10 alkyl, for example, methyl , ethyl , propyl, butyl , pentyl, and isopropyl, among which methyl and ethyl are preferred. X i+1 is the above-defined silylalkyl group, an unsubstituted monovalent hydrocarbon group, a monovalent hydrocarbon group substituted by an atom other than a carbon or hydrogen atom, or a monovalent hydrocarbon group substituted by a group containing an atom other than a carbon or hydrogen atom. Preferred unsubstituted monovalent hydrocarbon groups are those having 1-30 carbon atoms. Typical examples are alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, isopropyl, isobutyl, cyclopentyl and cyclohexyl groups; aryl groups such as phenyl, naphthyl, tolyl and xylyl groups; alkenyl groups such as vinyl, allyl, butenyl, pentenyl and hexenyl groups; and aralkyl groups such as benzyl and phenethyl groups. The monovalent hydrocarbon group substituted by an atom other than a carbon or hydrogen atom, or the monovalent hydrocarbon group substituted by a group containing an atom other than a carbon or hydrogen atom, is a monovalent hydrocarbon group substituted by a known organic group which can be present in various silicone compounds. Preferred examples are at least one monovalent hydrocarbon group having 1-30 carbon atoms, substituted by an alcoholic hydroxyl group, a phenolic hydroxyl group, an amino group, an alkoxy group, carboxyl group, nitrile group, a halogen atom, a cyclic or non-cyclic ether-containing group or a carboxylic acid ester-containing group. Specifically, the hydrocarbon group substituted by the alcoholic hydroxyl group includes 3-hydroxypropyl group, hydroxymethyl group and (hydroxyethoxy)propyl group; the hydrogen group substituted by the phenolic hydroxyl group includes hydroxyphenyl group and (hydroxyphenyl)propyl group; the hydrocarbon group substituted by the amino group includes aminopropyl group, aminomethyl group, N-butylaminopropyl group, N-cyclohexylaminopropyl group, N,N-dibutylaminopropyl group and N, N-dibutylaminomethyl group; the hydrocarbon group substituted by the alkoxy group includes 3-butoxypropyl group and 3,3-dimethoxypropyl group; the hydrocarbon group substituted by the carboxyl group includes 3-carboxylpropyl group and 10-carboxydecyl group; the hydrocarbon group substituted by the nitrile group includes 2-cyanoethyl group and 3-cyanopropyl group; the hydrocarbon group substituted by the halogen atom includes 3-chloropropyl group, chloromethyl group, 3,3,3-trifluoropropyl group, p-chloromethylphenethyl group and nonafluorohexyl group; the hydrocarbon group substituted by the cyclic ether-containing group includes glycidoxypropyl group, 5,6-oxyranylbuthyl group and tetrahydrofurfuryloxypropyl group; the hydrocarbon group substituted by the non-cyclic ether containing group includes methoxyethoxypropyl group, polyoxyethlenylpropyl group and polyoxypropylenylpropyl group; the hydrocarbon group substituted by the carboxylic acid ester-containing group includes acetoxypropyl group and ethoxycarbonylpropyl group; the hydrocarbon group substituted by the phenolic hydroxyl group and the alkoxy group includes 4-hydroxy-3-methoxyphenylpropyl group; the hydrocarbon group substituted by the alcoholic hydroxyl group and the carboxylic acid ester-containing group includes 6-acetoxy-5-hydroxyhexyl group; the hydrocarbon group substituted by the alcoholic hydroxyl group, the carboxylic acid ester-containing group and the ether-containing group includes 7-acryloxy-6-hydroxy-4-oxaheptyl group. i is an integer from 1 to 10 that indicates the number of generations of the silylalkyl group under consideration, i.e., it indicates the number of repetitions of this silylalkyl group. Thus, this silylalkyl group has the following general formula when the number of generations is 1: the following general formula when the number of generations is 2: and has the following general formula when the number of generations is 3. In these formulas, R 1 , R 2 , R 3 , b 1 , b 2 and b 3 each is defined as above. R 4 is an unsubstituted monovalent hydrocarbon group, a monovalent hydrocarbon group substituted by an atom other than a carbon or hydrogen atom, or a monovalent hydrocarbon group substituted by a group containing an atom other than a carbon or hydrogen atom as exemplified for X i+1 above. In a preferred embodiment of the present invention at least one of R 4 in a molecule is a monovalent hydrocarbon group substituted by an atom other than a carbon or hydrogen atom, or a monovalent hydrocarbon group substituted by a group containing an atom other than a carbon or hydrogen atom. The substituted hydrocarbon group may be those shown for X i+1 . The carbosiloxane dendrimer according to the present invention must contain at least 1 siloxane unit as represented by the general formula X 1 R 1 a SiO (3-a)/2 wherein when more than 1 siloxane unit is present the subject siloxane units may be the same or different and in a preferred embodiment comprises a polysiloxane structure having at least 2 silicon atoms forming the core of said carbosiloxane dendrimer. The structure may be a polysiloxane structure comprising siloxane units represented by the general formula X 1 R 1 a SiO (3-a)/2 (wherein X 1 , R 1 and a are as defined above) or a polysiloxane structure comprising siloxane units represented by said general formula and also siloxane units represented by the general formula R 1 c SiO (4-c)/2 (wherein R 1 is as defined above and c is an integer of from 0 to 3). The structural units in this organosiloxane comprise monofunctional siloxane units (M units) with the general formulas X 1 R 1 2 SiO 1/2 and R 1 3 SiO 1/2 , difunctional siloxane units (D units) with the general formulas X 1 R 1 SiO 2/2 and R 1 2 SiO 2/2 , trifunctional siloxane units (T units) with the general formulas X 1 SiO 3/2 and R 1 SiO 3/2 , and the tetrafunctional siloxane unit (Q unit) SiO 4/2 . The following are preferred embodiments of this organopolysiloxane: organopolysiloxane that contains at least one difunctional siloxane unit with the general formula R 1 2 SiO 2/2 or X 1 R 1 SiO 2/2 (R 1 and X 1 are defined as above); organopolysiloxane that contains at least 5 silicon atoms and is composed of siloxane units selected from the general formulas R 1 SiO 3/2 , X 1 SiO 3/2 , R 1 3 SiO 1/2 , and X 1 R 1 2 SiO 1/2 (R 1 and X 1 are defined as above); and organopolysiloxane that contains at least 6 silicon atoms and is composed of siloxane units selected from the general formulas SiO 4/2 , R 1 3 SiO 1/2 , and X 1 R 1 2 SiO 1/2 (R 1 and X 1 are defined as above). The subject carbosiloxane dendrimers can be more specifically exemplified by the following general formulas, in which X 1 and R 1 are defined as above and m, n, x, y, z, p, q, r, s, and t, which denote the number of siloxane units present in each molecule, have values ≥ 1 wherein p + q ≥ 5 and s + t ≥ 6. (X 1 R 1 2 SiO 1/2 ) p (R 1 SiO 3/2 ) q (X 1 SiO 3/2 ) r (X 1 R 1 2 SiO 1/2 ) s (SiO 4/2 ) t The carbosiloxane dendrimer according to the present invention can be prepared as a single compound or a mixture of compounds. The dispersity index of the molecular weight (polystyrene basis), that is, weight-average molecular weight/number-average molecular weight (M w /M n ), is preferably ≤ 2. According to a first embodiment of the present invention carbosiloxane dendrimers having an unsubsituted hydrocarbon group in a terminal position can be specifically exemplified by polymers with the following average molecular formulas. Specifically, the carbosiloxane dendrimers according to a second embodiment of the present Invention having a substituted hydrocarbon group can be represented by the following molecular formulae: The carbosiloxane dendrimer of the present invention can be produced by carrying out either one of the following processes (x) and (w) at least once using, as starting material, silicon bonded hydrogen-containing polysiloxane that contains at least 2 silicon atoms, having the general formula HR 1 a SiO (3-a)/2 (R 1 and a are as defined above) and, finally, the process (z) or (w). Specifically, there are methods comprising process (z) only, or processes (x) and (y) in alternation at least once and then process (z) after process (y) or process (w) after process (x). Process (x) In this process, the above-mentioned starting material or the silicon bonded hydrogen-containing carbosiloxane dendrimer produced by the following process (y) is addition-reacted with alkenyl group-containing alkoxysilane represented by the general formula R 5 Si (OR 3 ) 3 (R 3 is as defined above and R 5 is C2 to C10 alkenyl), in the presence of a platinum transition metal catalyst. Process (y) The alkoxy group-containing carbosiloxane dendrimer obtained by process (x) is reacted under acidic conditions with a disiloxane represented by the general formula below (wherein R 1 is as defined above) : Process (z) The starting material or the carbosiloxane dendrimer obtained by process (y) is addition-reacted with a compound having one non-conjugated alkenyl group in a molecule in the presence of a platinum transition metal catalyst. Process (w) The alkoxy group-containing carbosiloxane dendrimer obtained by process (x) is reacted under acidic conditions with disiloxane of the general formula below (wherein R 1 and R 4 are as defined above): Examples of the platinum transition metal catalyst used in processes (x) and (z) are chloroplatinic acid, alcohol-modified chloroplatinic acid, platinum-olefin complexes, and platinum-diketonate complexes. The platinum transition metal-catalyzed addition reaction effected using the platinum transition metal catalyst is preferably run with a slight excess of the alkenyl group-containing compound in order to completely react the silicon bonded hydrogen present in the starting material. After the reaction, the excess alkenyl group-containing alkoxysilane can be fractionated off and recovered by, for example, distillation under reduced pressure. This addition reaction can be run at an ambient temperature or with heating and can be run in a solvent that does not inhibit the reaction. Examples of the alkenyl group-containing alkoxysilane used in process (x) are vinyltrimethoxysilane, vinyltriethoxysilane, hexenyltrimethoxysilane and hexenyltriethoxysilane. In the first embodiment of the present invention preferred examples of the compound having one non-conjugated alkenyl group in a molecule used in process (z) may be butene, isobutene, hexene, octene, styrene, α-methylstyrene, vinyltris(trimethylsiloxy)silane and vinylbis(trimethylsiloxy)methoxysilane. According to the second embodiment of the present invention compounds having, in a molecule, one non-conjugated alkenyl group and at least one atom other than a carbon or hydrogen atom or a group containing an atom other than a carbon or hydrogen atom are used in process (z). Preferred examples are alkenyl compounds having 30 or less carbon atoms. Said at least one atom or group is selected from the group consisting of an alcoholic hydroxyl group, a phenolic hydroxyl group, an amino group, an alkoxy group, a carboxyl group, a nitrile group, a halogen atom, a cyclic or non-cyclic ether-containing group and a carboxylic acid ester-containing group. Specific examples are allyl alcohol, allyloxy ethanol, o-allylphenol, allylamine, butylallyl ether, undecylenic acid, allyl cyanide, acrylonitrile, allyl chloride, allylglycidyl ether and allyl methacrylate. The acidic substance used to produce the acidic condition in processes (y) and (w) is preferably hydrochloric acid, sulfuric acid, carboxylic acid or a mixture of the preceding. The silicon-bonded hydrogen is alcoholyzed in process (y) and as a result a small amount of the following monoalkoxysiloxy group may also be present. (wherein R 1 and R 3 are as define above) The above described carbosiloxane dendrimer of the present invention has a polysiloxane core and has a highly branched structure in which the siloxane bond and the silalkylene bond occur in alternation. It can be prepared in a high-molecular-weight form and it exhibits a narrow molecular weight distribution. Since in the first embodiment of the present invention the terminals of the branched structure are all unsubstituted hydrocarbon groups, the carbosiloxane dendrimer has low viscosity in spite of the highly branched structure, has a glass transition temperature as low as that of linear polysiloxane, and is hard to be crystallized. Consequently, the carbosiloxane dendrimer according to the first embodiment of the present invention is useful a releasing agent, a lubricating agent and a resin filler. According to the second embodiment of the present invention, the terminals of the branched structure have hydrocarbon groups substituted by various organic groups and, therefore, the physical property of the carbosiloxane dendrimer of the invention is governed by the chemical and physical properties of the organic groups. For example, the carbosiloxane dendrimer of the invention has hydrophilic groups of a polyether structure and the like and has high water solubility. The carbosiloxane dendrimer has reactive organic groups such as epoxy groups and amino groups and is characterized by high reactivity. Therefore, it is useful as a releasing agent, a lubricating agent, a resin modifying agent and a crosslinker. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows the 29 Si-nuclear magnetic resonance spectrum of the carbosiloxane dendrimer synthesized in Example 1. Figure 2 shows the 29 Si-nuclear magnetic resonance spectrum of the carbosiloxane dendrimer synthesized in Example 2. Figure 3 shows the 29 Si-nuclear magnetic resonance spectrum of the carbosiloxane dendrimer synthesized in Example 3. Figure 4 shows the 29 Si-nuclear magnetic resonance spectrum of the carbosiloxane dendrimer synthesized in Example 4. Figure 5 shows the 29 Si -nuclear magnetic resonance spectrum of the carbosiloxane dendrimer synthesized in Example 5. Figure 6 shows the 29 Si-nuclear magnetic resonance spectrum of the carbosiloxane dendrimer synthesized in Example 6. Figure 7 shows the 29 Si-nuclear magnetic resonance spectrum of the carbosiloxane dendrimer synthesized in Example 7. Figure 8 shows the 29 Si-nuclear magnetic resonance spectrum of the carbosiloxane dendrimer synthesized in Example 8. Figure 9 shows the 29 Si-nuclear magnetic resonance spectrum of the carbosiloxane dendrimer synthesized in Example 9. Figure 10 shows the 29 Si-nuclear magnetic resonance spectrum of the carbosiloxane dendrimer synthesized in Example 10. EXAMPLES The invention will be explained in greater detail below using working examples, in which the carbosiloxane dendrimer according to the present invention was identified by 29 Si-nuclear magnetic resonance analysis and gel permeation chromatographic analysis (solvent: toluene). Example 1 35.5g of vinyltris(trimethylsiloxy)silane and 0.04 g of a 3% isopropanolic chloroplatinic acid solution were introduced into a 100-mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and an addition funnel and were heated to 100°C under stirring. To this was gradually added 8.2 g of tetrakis (dimethylsiloxy) silane dropwise from the addition funnel so as to maintain the reaction temperature at 100°C. After completion of the addition, the reaction solution was heated for 1 hour at 120°C. After cooling, the reaction solution was concentrated under reduced pressure to give 40.5 g of a very light brown liquid. It was confirmed that the viscosity of the obtained liquid at 25°C was 98 centistokes, the glass transition temperature measured by a differential scanning calorimeter was -85.1°C and no crystallization process as normally seen in straight-branched polydimethylsiloxane occurred. Analysis of this reaction product by 29 Si-nuclear magnetic resonance analysis showed it to be carbosiloxane dendrimer represented by the average molecular formula shown below. Using gel permeation chromatography, this carbosiloxane dendrimer was found to have a number-average molecular weight of 2,180 (polystyrene basis) and a dispersion index of 1.06. Example 2 107 g of vinyltrimethoxysilane and 0.04 g of a 3% isopropanolic chloroplatinic acid solution were introduced into a 200-mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and an addition funnel and were heated to 100°C under stirring. To this was gradually added 49.4 g of tetrakis(dimethylsiloxy)silane dropwise from the addition funnel so as to maintain the reaction temperature at 100°C. After completion of the addition, the reaction solution was heated for 1 hour at 120°C. After cooling, the reaction solution was concentrated under reduced pressure to give 138 g of a very light brown liquid. The liquid was taken as intermediate A. 210 g of 1,1,3,3,-tetramethyl-1,3-divinyldisiloxane, 67.6 g of acetic acid and 0.20 g of trifluoromethane sulfonic acid were placed in a 2-liter four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and an addition funnel and were heated to 50°C under stirring. 120 g of the intermediate A prepared as described above was gradually added dropwise from the addition funnel for 1 hour. After completion of the addition, the reaction solution was stirred at 60°C for 5 hours. After cooling, the reaction solution was transferred to a separatory funnel. The solution was washed twice with 200 mL of water, then once with 100 mL of saturated aqueous sodium bicarbonate solution, and finally dried over anhydrous sodium sulfate. The solids were filtered off and the resulting solution was concentrated under reduced pressure to yield 212 g of a colorless and transparent liquid. Analysis of this reaction product by 29 Si-nuclear magnetic resonance analysis showed it to be carbosiloxane dendrimer represented by the average molecular formula given below having an average of 12 vinyl groups in each molecule. Using gel permeation chromatography, this carbosiloxane dendrimer was found to have a number-average molecular weight of 1,211 (polystyrene basis) and a dispersion index of 1.28. Example 3 182 g of vinyltriethoxysilane and 0.28 g of a 3% isopropanolic chloroplatinic acid solution were introduced into a 300-mL three-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and an addition funnel and were heated to 100°C under stirring. 100 g of methyltris(dimethylsiloxy)silane was gradually added dropwise from the addition funnel so as to maintain the reaction temperature at 100°C. After completion of the addition, the reaction solution was heated for 1 hour at 120°C. After cooling, the reaciton solution was concentrated under reduced pressure to give 266 g of a very light brown liquid. The liquid was taken as intermediate E. 127 g of 1,1,3,3,-tetramethyldisiloxane, 33 mL of concentrated hydrochloric acid, 66 mL of water and 66 mL of isopropanol were charged into a 500 mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and an addition funnel, and were stirred. 100 g of the intermediate E prepared as described above was then gradually added dropwise from the addition funnel for 1 hour. After completion of the addition, the reaction solution was stirred at room temperature for 1 hour. The reaction solution was transferred to a separatory funnel, the lower layer was separated off, and the remaining upper layer was washed twice with 30 mL of water, then once with 30 mL of saturated aqueous sodium bicarbonate solution, and finally dried over anhydrous sodium sulfate. The solids were filtered off and the resulting solution was concentrated under reduced pressure to yield 156 g of a colorless and transparent liquid. The liquid was taken as intermediate F. Finally, 30.0 g of the intermediate F prepared as above and 0.03 g of a 3% isopropanol solution were introduced into a 100 mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser and an addition funnel and were heated to 100°C under stirring. To this, 24.6 g of hexene was gradually added dropwise from the addition funnel so as to maintain the reaction temperature at 100°C. After completion of the addition, the reaction solution was heated for 1 hour at 100°C. After cooling, the reaction solution was concentrated under reduced pressure to yield 44.4 g of a very light brown liquid. Analysis of this reaction product by 29 Si-nuclear magnetic resonance analysis showed it to be carbosiloxane dendrimer represented by the average molecular formula given below. Using gel permeation chromatography, this carbosiloxane dendrimer was found to have a number-average molecular weight of 2,476 (polystyrene basis) and a dispersion index of 1.08. Example 4 121 g of vinyltrimethoxysilane and 0.2 g of a 3% isopropanolic chloroplatinic acid solution were charged into a 200-mL four-neck flask equipped with a sitrrer, a thermometer, a reflux condenser and an addition funnel and were heated to 100°C under stirring. 50 g of 1,1,3,3-tetramethyldisiloxane was gradually added dropwise from the addition funnel so as to maintain the reaction temperature at 100°C. After completion of the addition, the reaction solution was heated for 1 hour at 120°C. After cooling, the reaction solution was concentrated under reduced pressure to give 158 g of a very light brown liquid. The liquid was taken as intermediate G. 180 g of 1,1,3,3 - tetramethyldisiloxane, 50 mL of concentrated hydrochloric acid, 100 mL of water and 100 mL of isopropanol were subsequently placed in a 1-L four-neck flask equipped with a stirrer, a thermometer, a reflux condenser and an addition funnel and were stirred. 158 g of the intermediate G prepared as described above was then gradually added dropwise from the addition funnel over 1 hour. After completion of the addition, the reaction solution was stirred at room temperature for 1 hour. The reaction solution was then transferred to a separatory funnel, the lower layer was separated off, and the remaining upper layer solution was washed twice with 100 mL of water, then once with 100 mL of saturated aqueous sodium bicarbonate solution, and finally dried over anhydrous magnesium sulfate. The solids were filtered off and the resulting solution was concentrated under reduced pressure to yield 233 g of a colorless and transparent liquid. The liquid was taken as intermediate H. Finally, 133 g of vinyltris(trimethylsiloxy)silane and 0.09 g of a 3% isopropanolic chloroplatinic acid solution were introduced into a 200mL four neck flask and were heated to 100°C under stirring. 40.0 g of the intermediate H prepared as above was gradually added dropwise from the addition funnel to maintain the reaction temperature of 100°C. After completion of the addition, the reaction solution was heated for 1 hour at 120°C. After cooling, the reaction solution was concentrated under a reduced pressure to give 127 g of a very light brown liquid. Analysis of this reaction product by 29 Si-nuclear magnetic resonance analysis showed it to be carbosiloxane dendrimer represented by the average molecular formula shown below. Using gel permeation chromatography, this carbosiloxane dendrimer was found to have a number-average molecular weight of 2,911 (polystyrene basis) and a dispersion index of 1.08. Example 5 49.4 g of vinyltrimethoxysilane and 0.04 g of a 3% isopropanolic chloroplatinic acid solution were charged into a 100-mL four-neck flask equipped with a stirrer, a thermometer, a relux condenser and an addition funnel and were heated to 100°C under stirring. 30.0 g of polysiloxane represented by the average molecular formula shown below was gradually added dropwise from the addition funnel so as to maintain the reaction temperature at 100°C. After completion of the addition, the reaction solution was heated for 1 hour at 120°C. After cooling, the reaction solution was concentrated under reduced pressure to give 63.1 g of a very light brown liquid. The liquid was taken as intermediate K. 33 g of1,1,3,3-tetramethyldisiloxane, 13 mL of concentrated hydrochloric acid, 27 mL of water and 27 mL of isopropanol were placed in a 200 mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser and an addition funnel and were stirred. To this, 40.0 g of the intermediate K prepared as described above was gradually added dropwise from the addition funnel for 1 hour. After completion of the addition, the reaction solution was stirred at room temperature for 1 hour. The reaction solution was transferred to a separatory funnel, the lower layer was separated off, and the remaining upper layer solution was washed twice with 20 mL of water, then once with 20 mL of saturated aqueous sodium bicarbonate solution, and finally dried over anhydrous magnesium sulfate. The solids were filtered off and the resulting solution was concentrated under reduced pressure to yield 45.4 g of a colorless and transparent liquid. The liquid was taken as intermediate L. Finally, 65.5 g of α-methylstyrene and 0.04 g of a 3% isopropanolic chloroplatinic acid solution were introduced into a 100-mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser and an addition funnel and were heated to 100ÚC under stirring. 24.0 g of the intermediate L obtained as described above was gradually added dropwise from the addition funnel so as to maintain the reaction temperature at 100ÚC. After completion of the addition, the reaction solution was heated for 1 hour at 120ÚC. After cooling, the reaction solution was concentrated under reduced pressure to give 35.1 g of a very light brown liquid. Analysis of this reaction product by 29 Si-nuclear magnetic resonance analysis showed it to be carbosiloxane dendrimer represented by the average molecular formula given below. Using gel permeation chromatography, this carbosiloxane dendrimer was found to have a number-average molecular weight of 3,830 (polystyrene basis) and a dispersion index of 1.75. Example 6 214 g of vinyltrimethoxysilane and 0.16 g of a 3% isopropanolic chloroplatinic acid solution were introduced into a 500-mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser and an addition funnel and were heated to 100°C under stirring. 100 g of polysiloxane represented by the average compositional formula {H(CH 3 ) 2 SiO 1/2 } 10 (SiO 4/2 ) 5 was gradually added dropwise from the addition funnel so as to maintain the reaction temperature at 100°C. After completion of the addition, the reaction solution was heated for 1 hour at 120°C. After cooling, the reaction solution was concentrated under reduced pressure to give 234 g of a very light brown liquid. The liquid was taken as intermediate M. 468 g of 1,1,3,3-tetramethyldisiloxane, 75 ml of concentrated hydrochloric acid, 150 mL of water and 150 mL of isopropanol were subsequently placed in a 1000 mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser and an addition funnel and were stirred. 220 g of the intermediate M prepared as described above was gradually added dropwise from the addition funnel for 1 hour. After completion of the addition, the reaction solution was stirred at room temperature for 1 hour. The reaction solution was subsequently transferred to a separatory funnel, washed twice with 200 mL of water, then once with 100 mL of saturated aqueous sodium bicarbonate solution, and finally dried over anhydrous magnesium sulfate. The produced solids were filtered off and the resulting solution was concentrated under reduced pressure to yield 273 g of a colorless and transparent liquid. The liquid was taken as intermediate N. 105 g of vinyltris(trimethylsiloxy)silane and 0.07 g of a 3% isopropanolic chloroplatinic acid solution were introduced into a 200-mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser and an addition funnel and were heated at 100°C under stirring. 35.0 g of the intermediate N obtained as described above was gradually added dropwise from the addition funnel so as to maintain the reaction temperature at 100°C. After completion of the addition, the reaction solution was heated for 1 hour at 120°C. After cooling, the reaction solution was concentrated under reduced pressure to give 80.3 g of a very light brown liquid. Analysis of this reaction product by 29 Si-nuclear magnetic resonance analysis showed it to be carbosiloxane dendrimer represented by the average molecular formula given below. Using gel permeation chromatography, this carbosiloxane dendrimer was found to have a number-average molecular weight of 6,586 (polystyrene basis) and a dispersion index of 1.14. Example 7 107 g of vinyltristrimethylsiloxysilane and 0.04 g of a 3% isopropanolic chloroplatinic acid solution were introduced into a 200-mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and an addition funnel and were heated to 100°C under stirring. To this was gradually added 49.4 g of tetrakis (dimethylsiloxy) silane dropwise from the addition funnel so as to maintain the reaction temperature at 100°C. After completion of the addition, the reaction solution was heated for 1 hour at 120°C. After cooling, the reaction solution was concentrated under reduced pressure to give 138 g of a very light brown liquid. The liquid was taken as intermediate A. 80.6 g of 1,1,3,3-tetramethyldisiloxane, 72.1 g of acetic acid and 0.11 g of trifluoromethane sulfonic acid were chared into a 300mL four-neck flask equipeed with a stirrer, a thermometer, a reflux condenser and an addition funnel and were heated 40°C under stirring. To this was gradually added dropwise from the addition funnel 76.8 g of the intermediate A prepared as described above for 1 hour. After completion of the addition, the reaction solution was stirred at 50°C for 1 hour. The reaction solution was transferred to a separatory funnel, the lower layer was separated off, and the remaining upper layer solution was washed twice with 50 mL of water, then once with 50 mL of saturated aqueous sodium bicarbonate solution, and dried over anhydrous magnesium sulfate. The solids were filtered off and the resulting solution was concentrated under reduced pressure to yield 119 g of a colorless and transparent liquid. The liquid was taken as intermediate B. Further, 88.9 g of vinylmethoxysilane and 0.04 g of a 3% isopropanolic chloroplatinic acid solution were introduced into a 200-mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser and an addition funnel and were heated to 100°C under stirring. 60.5 g of the intermediate B obtained as described above was gradually added dropwise from the addition funnel so as to maintain the reaction temperature at 100°C. After completion of the addition, the reaction solution was heated for 1 hour at 120°C. After cooling, the reaction solution was concentrated under reduced pressure to give 134 g of a very light brown liquid.. The liquid was taken as intemrediate C. 75.1 g of 1,1,3,3-tetramethyldisiloxane, 53.7 g of acetic acid and 66.9 g of the intermediate C obtained as above, were charged into a 300 mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser and an addition funnel and were heated to 50°C under stirring. To this was added 0.08 g of trifluoromethane sulfonic acid and the reaction solution was stirred at 50°C for 1 hour. The reaction solution was transferred to a separatory funnel, the lower layer was separated off, and the remaining upper layer solution was washed twice with 30 mL of water, then once with 30 mL of saturated aqueous sodium bicarbonate solution, and dried over anhydrous magnesium sulfate. The solids were filtered off and the resulting solution was concentrated under reduced pressure to yield 77.1 g of a colorless and transparent liquid. The liquid was taken as intermediate D. Finally, 46.1 g of one-end-arylated polyoxyethylene glycol (dodecamer) and 0.07 g of a 3% isopropanolic chloroplatinic acid ssolution were introduced into a 100-mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser and an addition funnel and were heated to 80°C under stirring. 15.0 g of the intermediate D obtained as described above was gradually added dropwise from the addition funnel so as to maintain the reaction temperature at 85°C. After completion of the addition, the reaction solution was heated for 1 hour at 100°C. After cooling, the reaction solution was concentrated under reduced pressure to give 64.0 g of a very light brown liquid. Analysis of this reaction product by 29 Si-nuclear magnetic resonance analysis showed it to be carbosiloxane dendrimer represented by the average molecular formula given below. Using gel permeation chromatography, this carbosiloxane dendrimer was found to have a number-average molecular weight of 2,603 (polystyrene basis) and a dispersion index of 1.32. Example 8 88.9 g of vinyltrimethoxysilane and 0.04 g of a 3% isopropanolic chloroplatinic acid solution were introduced into a 200-mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and an addition funnel and were heated to 100°C under stirring. To this was gradually added 30.1 g of 1,3,5,7-tetramethylcyclotetrasilane dropwise from the addition funnel so as to maintain the reaction temperature at 100°C. After completion of the addition, the reaction solution was heated for 1 hour at 120°C. After cooling, the reaction solution was concentrated under reduced pressure to give 100 g of a very light brown liquid. The liquid was taken as intermediate I. 93.0 g of 1,1,3,3-tetramethyldisiloxane, 27 mL of concentrated hydrochloric acid, 53 mL of water and 53 mL of isopropanol were placed in a 500 mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and an addition funnel and were stirred. 180.0 g of the intermediate I prepared as described above was gradually added dropwise from the addition funnel for 1 hour. After completion of the addition, the reaction solution was stirred at a room temperature for 1 hour. The reaction solution was transferred to a separatory funnel, the lower layer was separated off, and the remaining upper layer solution was washed twice with 50 mL of water, then once with 50 mL of saturated aqueous sodium bicarbonate solution, and dried over anhydrous magnesium sulfate. The solids were filtered off and the resulting solution was concentrated under reduced pressure to yield 98.5 g of a colorless and transparent liquid. The liquid was taken as intermediate J. Further, 45.7 g of allylglycidyl ether and 0.04 g of a 3% isopropanolic chloroplatinic acid solution were introduced into a 100-mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser and an addition funnel and were heated to 100°C under stirring. 35.0 g of the intermediate J obtained as described above was gradually added dropwise from the addition funnel so as to maintain the reaction temperature at 100°C. After completion of the addition, the reaction solution was heated for 1 hour at 120°C. After cooling, the reaction solution was concentrated under reduced pressure to give 60.0 g of a very light brown liquid. Analysis of this reaction product by 29 Si-nuclear magnetic resonance analysis showed it to be carbosiloxane dendrimer represented by the average molecular formula given below. Using gel permeation chromatography, this carbosiloxane dendrimer was found to have a number-average molecular weight of 2,061 (polystyrene basis) and a dispersion index of 1.21. Example 9 49.4 g of vinyltriethoxysilane and 0.04 g of a 3% isopropanolic chloroplatinic acid solution were introduced into a 100-mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and an addition funnel and were heated to 100°C under stirring. 30.0 g of polysiloxane of the average molecular formular shown below was gradually added dropwise from the addition funnel so as to maintain the reaction temperature at 100°C. After completion of the addition, the reaction solution was heated for 1 hour at 120°C. After cooling, the reaction solution was concentrated under reduced pressure to give 63.1 g of a very light brown liquid. The liquid was taken as intermediate K. 33.9 g of 1,1,3,3-tetramethyldisiloxane, 13 mL of concentrated hydrochloric acid, 27 mL of water and 27 mL of isopropanol were charged into a 200 mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and an addition funnel, and were stirred. 40.0 g of the intermediate K prepared as described above was then gradually added dropwise from the addition funnel for 1 hour. After completion of the addition, the reaction solution was stirred at room temperature for 1 hour. The reaction solution was transferred to a separatory funnel, the lower layer was separated off, and the remaining upper layer was washed twice with 20 mL of water, then once with 20 mL of saturated aqueous sodium bicarbonate solution, and dried over anhydrous sodium sulfate. The solids were filtered off and the resulting solution was concentrated under reduced pressure to yield 45.4 g of a colorless and transparent liquid. The liquid was taken as intermediate L. Finally, 62.4 g of allyl acetate and 0.05 g of a 3% isopropanolic chloroplatinic solution were introduced into a 100 mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser and an addition funnel and were heated to 100°C under stirring. To this, 27.0 g of the intermediate L was gradually added dropwise from the addition funnel so as to maintain the reaction temperature at 90°C. After completion of the addition, the reaction solution was heated for 1 hour at 100°C. After cooling, the reaction solution was concentrated under reduced pressure to yield 33.3 g of a very light brown liquid. Analysis of this reaction product by 29 Si-nuclear magnetic resonance analysis showed it to be carbosiloxane dendrimer represented by the average molecular formula given below. Using gel permeation chromatography, this carbosiloxane dendrimer was found to have a number-average molecular weight of 2,894 (polystyrene basis) and a dispersion index of 1.73. Example 10 214 g of vinyltrimethoxysilane and 0.16 g of a 3% isopropanolic chloroplatinic acid solution were charged into a 500-mL four-neck flask equipped with a stirrer, a thermometer, a reflux condenser and an addition funnel and were heated to 100°C under stirring. 100 g of polysiloxane represented by the average compositional formula {H(CH 3 ) 2 SiO 1/2 } 10 (SiO 4/2 ) 5 was gradually added dropwise from the addition funnel so as to maintain the reaction temperature at 100°C. After completion of the addition, the reaction solution was heated for 1 hour at 120°C. After cooling, the reaction solution was concentrated under reduced pressure to give 234 g of a very light brown liquid. The liquid was taken as intermediate M. 468 g of 1,1,3,3-tetramethyldisiloxane, 75 mL of concentrated hydrochloric acid, 150 mL of water and 150 mL of isopropanol were subsequently placed in a 1-L four-neck flask equipped with a stirrer, a thermometer, a reflux condenser and an addition funnel and were stirred. 220 g of the intermediate M prepared as described above was then gradually added dropwise from the addition funnel over 1 hour. After completion of the addition, the reaction solution was stirred at room temperature for 1 hour. The reaction solution was then transferred to a separatory funnel, the lower layer was separated off, and the remaining upper layer solution was washed twice with 100 mL of water, then once with 100 mL of saturated aqueous sodium bicarbonate solution, and dried over anhydrous magnesium sulfate. The solids were filtered off and the resulting solution was concentrated under reduced pressure to yield 273 g of a colorless and transparent liquid. The liquid was taken as intermediate N. Finally, 50.0 g of the intermediate N prepared as above and 0.82 g of a 3% isopropanolic chloroplatinic acid solution were introduced into a 100mL four neck flask and were heated to 100°C under stirring. 18.1 g of N,N-bis(trimethylsilyl)allylamine was gradually added dropwise from the addition funnel to maintain the reaction temperature of 100°C. After completion of the addition, the reaction solution was heated for 1 hour at 120°C and 10.0 g was added thereto and heated under reflux for another 1 hour. After cooling, the reaction solution was concentrated under a reduced pressure to give 66.5 g of a very light brown liquid. Analysis of this reaction product by 29 Si-nuclear magnetic resonance analysis showed it to be carbosiloxane dendrimer represented by the average molecular formula shown below. Using gel permeation chromatography, this carbosiloxane dendrimer was found to have a number-average molecular weight of 4,830 (polystyrene basis) and a dispersion index of 1.52.

Claims: Carbosiloxane dendrimer that contains at least one siloxane unit with the general formula X 1 R 1 a SiO (3-a)/2 where R 1 is C 1 to C 10 alkyl or aryl, a is an integer from 0 to 2, and X 1 is the silylalkyl group with the following formula at i = 1 where R 1 is C 1 to C 10 alkyl or aryl , R 2 is C 2 to C 10 alkylene, R 3 is C 1 to C 10 alkyl, X i+1 is the above-defined silylalkyl group at i = i + 1 , an unsubstituted monovalent hydrocarbon group, a monovalent hydrocarbon group substituted by an atom other than a carbon or hydrogen atom, or a monovalent hydrocarbon group substituted by a group containing an atom other than a carbon or hydrogen atom, i is an integer with a value from 1 to 10 that specifies the generation of said silylalkyl group, and b i is an integer from 0 to 3 with the proviso that b 1 in at least one X 1 in each molecule is an integer from 0 to 2, and which has at least one siloxy group represented by the general formula: wherein R 1 is a C 1 to C 10 alkyl or aryl group, and R 4 is a monovalent unsubstituted hydrocarbon group, a monovalent hydrocarbon group substituted by an atom other than a carbon or hydrogen atom, or a monovalent hydrocarbon group substituted by a group containing an atom other than a carbon or hydrogen atom and wherein when more than 1 siloxane unit is present the subject siloxane units is the same or different. The carbosiloxane dendrimer according to claim 1, that has the following general formula in which R 1 and X 1 are defined as in claim 1. The carbosiloxane dendrimer according to claim 1 comprising a polysiloxane structure containing at least 2 silicon atoms as a core and at least one of said siloxane units. The carbosiloxane dendrimer according to claim 1, that contains at least one difunctional siloxane unit with the general formula R 1 2 SiO 2/2 or X 1 R 1 SiO 2/2 whereby R 1 and X 1 are defined as in claim 1 in the polysiloxane structure comprising the core. The carbosiloxane dendrimer according to claim 1, wherein the polysiloxane structure comprising the core contains at least 5 silicon atoms and is composed of siloxane units selected from the general formulas R 1 SiO 3/2 , X 1 SiO 3/2 , R 1 3 SiO 1/2 , and X 1 R 1 2 SiO 1/2 whereby R 1 and X 1 are defined as in claim 1. The carbosiloxane dendrimer according to claim 1, wherein the polysiloxane structure comprising the core contains at least 6 silicon atoms and is composed of siloxane units selected from the general formulas SiO 4/2 , R 1 3 SiO 1/2 , and X 1 R 1 2 SiO 1/2 whereby R 1 and X 1 are defined as in claim 1. The carbosiloxane dendrimer according to any of the preceding claims, whose molecular weight, determined on a polystyrene basis, has a dispersity index no greater than 2. A process for preparing carbosiloxane dendrimers comprising: a) reacting an Si-H-functional polysiloxane that contains at least 2 silicon atoms and at least one siloxane unit with the general formula HR 1 a Si (3-a)/2 whereby said silicon atoms may belong to said siloxane unit(s) or may be separate and R 1 is independently selected from C 1 to C 10 alkyl or aryl and a is an integer from 0 to 2 with an alkenyl-functional alkoxy silane with the general formula R 5 Si(OR 3 ) 3 , whereby R 3 is independently selected from C 1 to C 10 alkyl and R 5 is selected from C 2 to C 10 alkenyl in the presence of a platinum containing catalyst; b) reacting the product of step a) with a disiloxane with the general formula whereby R 1 is independently selected from C 1 to C 10 alkyl or aryl and R 6 is either hydrogen or R 4 as defined in claim 1 under acidic conditions c) in case R 6 in the disiloxane in step b) is hydrogen addition-reacting the reaction product of step b) with a compound having in its molecule one non-conjugated alkenyl group and optionally at least one atom other than a carbon or hydrogen atom or a group containing an atom other than a carbon or hydrogen atom in the presence of a platinum transition metal catalyst. The process of claim 8 further comprising a step d) wherein the product of step b) in case R 6 is hydrogen is used as SiH-functional polysiloxane for reacting with an alkenyl-functional alkoxysilane as defined for step a) and thereafter reacting the product of step d) with a disiloxane with the general formula whereby R 1 is independently selected from C 1 to C 10 alkyl or aryl and R 6 is either hydrogen or R 4 as defined in claim 1 under acidic conditions and in case R 6 is hydrogen reacting said product in accordance with step c). The process of claim 9 whereby step b) under the proviso that R 6 is hydrogen and step d) are conducted in alternating sequence whereby, if the last step in said sequence is step d) this product is thereafter reacted with under acidic conditions, wherein R 1 and R 4 are defined as in claim 1 or if the last step in said sequence is step b) this product is thereafter reacted with a compound having in its molecule one non-conjugated alkenyl group and optionally at least one atom other than a carbon or hydrogen atom or a group containing an atom other than a carbon or hydrogen atom in the presence of a platinum transition metal catalyst.

Inventors: ONODERA SATOSHI, YOSHITAKE MAKOTO, ONODERA, SATOSHI, YOSHITAKE, MAKOTO
Applicants: DOW CORNING TORAY SILICONE, DOW CORNING TORAY SILICONE COMPANY, LTD.
Application year: 1999
Main classification: C08G77
IPC codes: C08G77, C08G83