| PATENT NUMBER | This data is not available for free |
| PATENT GRANT DATE | 23.11.1999 |
| PATENT TITLE |
alpha., .omega.-polymethacrylate glycols, methods for their synthesis and their use for the preparation of polymers, particularly polyurethanes and polyesters |
| PATENT ABSTRACT |
alpha., .omega.-polymethacrylate glycols of the general formula ##STR1## are prepared and a method for their synthesis and their use as only or partial glycol component for the preparation of polyesters and polyurethanes and for the modification of alkyd and epoxide resins are described. |
| PATENT INVENTORS | This data is not available for free |
| PATENT ASSIGNEE | This data is not available for free |
| PATENT FILE DATE | September 24, 1997 |
| PATENT FOREIGN APPLICATION PRIORITY DATA | This data is not available for free |
| PATENT REFERENCES CITED |
Markromolekulare Stoffe, Hert Bartl, et al, 1987, 3 pages. Functionalization of PMMA by Afuntional "Iniferter", G. Clouet, 1989, 15 Pgs. Telechelic Polymers, J. Rietveld, et al, 1983, 5 pages. |
| PATENT CLAIMS |
We claim: 1. .alpha.,.omega.-polymethacrylate glycols of the general formula ##STR5## wherein R.sup.1 is an optionally halogenated alkyl group with 1 to 10 carbon atoms, R.sup.2 (1) is a divalent, aliphatic, optionally unsaturated hydrocarbon group with 2 to 20 carbon atoms, a cycloaliphatic hydrocarbon group with 5 to 10 carbon atoms or an aliphatic-aromatic hydrocarbon group with 8 to 20 carbon atoms, (2) a divalent, aliphatic ether group --R.sup.5 --O--R.sup.6, the R.sup.5 and R.sup.6 groups of which together have 4 to 20 carbon atoms, or (3) a polyether group of the general formula --(C.sub.n H.sub.2n O).sub.m --C.sub.p H.sub.2p, wherein the subscript n has a value of 2 to 4, the subscript m a value of not less than 1 and the subscript p a value of 2, 3 or 4, R.sup.3 is a residue of a chain transfer agent having a terminal hydroxyl group and is selected from the group consisting of --S--CH.sub.2 CH.sub.2 --OH, --S--CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 --OH, --S--CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 --OH and --S--CH.sub.2 --C.sub.6 H.sub.4 --CH.sub.2 OH group, and a has a value of not less than 4. 2. .alpha.,.omega.-polymethacrylate glycols of the formula ##STR6## R.sup.1 is an optionally halogenated alkyl group with 1 to 10 carbon atoms, R.sup.2 (1) is a divalent, aliphatic, optionally unsaturated hydrocarbon group with 2 to 20 carbon atoms, a cycloaliphatic hydrocarbon group with 5 to 10 carbon atoms or an aliphatic-aromatic hydrocarbon group with 8 to 20 carbon atoms, (2) a divalent, aliphatic ether group --R.sup.5 --O--R.sup.6, the R.sup.5 and R.sup.6 groups of which together have 4 to 20 carbon atoms, or (3) a polyether group of the general formula --(C.sub.n H.sub.2n O).sub.m --C.sub.p H.sub.2p, wherein the subscript n has a value of 2 to 4, the subscript m a value of not less than 1 and the subscript p a value of 2, 3 or 4, R.sup.3 is a residue of a chain transfer agent having a terminal hydroxyl group and is selected from the group of --S--CH.sub.2 CH.sub.2 --OH, --S--CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 --OH, and a has a value of not less than 4, obtained by reacting polymethacrylate esters of a general formula ##STR7## which are obtained by free radical polymerization in presence of a chain-length regulator and wherein the R.sup.1 and the R.sup.3 groups and the subscript a have the meanings already given, with a glycol having the formula HO--R.sup.2 --OH at a temperature of between about 70.degree. to 140.degree. C., in the presence of a non-basic transesterification catalyst and optionally a solvent and removing the unreacted glycol by distillation or by washing it out with a solvent in which the glycol is soluble and the polymer is insoluble. |
| PATENT DESCRIPTION |
FIELD OF INVENTION The invention relates to .alpha., .omega.-polymethacrylate glycols with two terminal hydroxyl groups. The invention furthermore relates to a method for the synthesis of such .alpha., .omega.-polymethacrylate glycols, as well as the preparation of polymers, particularly polyurethanes and polyesters, where the reactive starting materials are said glycols. The invention also relates to modifying alkyd and epoxide resins using the inventive glycols as modifiers. BACKGROUND INFORMATION AND PRIOR ART The synthesis of polymethacrylates with terminal functional groups and, in particular, with terminal hydroxyl groups, was attempted in various ways in recent years, since such compounds are of particular interest for the preparation of block copolymers, for example, for the preparation of polyesters or polyurethanes. In particular, attempts have been made to obtain such polymethacrylate glycols by way of group transfer polymerization. However, extremely high purity of the reagents used and the strict exclusion of air moisture are a prerequisite for carrying out the group-transfer reaction. By using initiators, which are listed in Houben-Weyl, Methoden der organischen Chemie (Methods of Organic Chemistry), volume E 20/Part 1, Table 18, pages 158 ff. and which can be synthesized only at great cost, only monofunctional polymers are obtained, which have a narrow molecular weight distribution. The synthesis of .alpha., .omega. difunctional polymers by means of this, so far, only method is not possible or possible only incompletely at great expense (D. Y. Sogah and O. W. Webster, J. Polym. Sci., Polym. Lett. Ed. 21, 927 (1983)). Another way of synthesizing .alpha., .omega.-terminated polymethacrylates was recently described using thiuram disulfides, which contain the hydroxyethyl groups. The synthesis was carried out according to the so-called "Iniferter" technique (initiator, transfer agent, terminator). Admittedly, the products obtained had a functionality, which comes close to the desired 2. However, the products, due to their high sensitivity to hydrolytic and thermal effects, can be used only to a limited degree (C. P. Reghunadham et al., J. Polymer Sci., part A: Pol. Chem. 27, 1795 (1989)). The present invention is concerned with the technical problem of synthesizing such .alpha., .omega.-polymethacrylate glycols readily, the content of polymethacrylates with a functionality of less than 2 or more than 2 being, as far as possible, 0. OBJECT OF THE INVENTION An object of the present invention is .alpha., .omega.-polymethacrylate glycols. Another object of the invention is a method of synthesizing the inventive glycols. Yet another object of invention is the preparation of polymers with inventive glycols as reactive starting materials. The glycols are also utilized in modifying alkyd and epoxide resins. The inventive .alpha., .omega.-polymethacrylate glycols have the general formula ##STR2## wherein R.sup.1 is an optionally halogenated, alkyl group with 1 to 10 carbon atoms, R.sup.2 (1) is a divalent, aliphatic, optionally unsaturated hydrocarbon group with 2 to 20 carbon atoms, a cycloaliphatic hydrocarbon group with 5 to 10 carbon atoms or an aliphatic-aromatic hydrocarbon group with 8 to 20 carbon atoms, (2) a divalent, aliphatic ether group --R.sup.5 --O--R.sup.6, the R.sup.5 and R.sup.6 groups of which together have 4 to 20 carbon atoms, or (3) a polyether group of the general formula --(C.sub.n H.sub.2n O).sub.m --C.sub.p H.sub.2p, wherein the subscript n has a value of 2 to 4, the subscript m a value of not less than 1 and the subscript p a value of 2, 3 or 4, R.sup.3 is a group of a known chain-length regulator, which has a terminal hydroxyl group, and a has a value of not less than 4. R.sup.1 preferably is a methyl, butyl or 2-ethylhexyl group, R.sup.2 can have various meanings and preferably is (1) a divalent alkylene group with 2 to 12 and particularly 2 to 6 carbon atoms, a cyclohexyl group or a xylylene group, (2) a divalent aliphatic ether group, particularly the --CH.sub.2 --CH.sub.2 O--CH.sub.2 --CH.sub.2 -- group, or (3) a polyether group having the formula --(C.sub.n H.sub.2n O).sub.m --C.sub.p H.sub.2p --, wherein n=2 to 2.5, m=5 to 100 and p=3. It is of particular importance that the R.sup.3 group is a group of a known chain-length regulator, which has a terminal hydroxyl group. Preferably the R.sup.3 group represents the --S--CH.sub.2 CH.sub.2 --OH, --S--CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 --OH, --S--CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 CH.sub.2 --OH or --S--CH.sub.2 --C.sub.6 H.sub.4 --CH.sub.2 OH group. Examples of inventive compounds are ##STR3## The method for the synthesis of the inventive compounds is characterized in that, polymethacrylate esters of the general formula, ##STR4## which are obtained by free radical polymerization in the presence of chain-length regulator and wherein the R.sup.1 and the R.sup.3 groups and the subscript a have the meanings already given, are reacted with a glycol having the formula HO--R.sup.2 --OH at temperatures of 70.degree. to 140.degree. C., optionally in the presence of a solvent, with the addition of known, non-basic transesterification catalysts in a molar ratio of polymethacrylate ester to HO--R.sup.2 --OH of 1:1 to 1:10, and the excess of unreacted glycol is removed by known methods, such as distillation or by washing it out with a solvent, in which the glycol is soluble and the polymer is insoluble. Surprisingly, it has been observed that the terminal ester group at the tertiary carbon atom surprisingly reacts appreciably more rapidly than the ester groups at the other end of the chain or even in the chain at quaternary carbon atoms. A molar ratio of polymethacrylate ester to HO--R.sup.2 --OH of 1:1 to 1:5 is particularly preferred. The preferred temperature range of the transesterification is from 90.degree. to 130.degree. C. Examples of polymethacrylate esters, which can be used for the inventive method, are poly(methyl methacrylate), poly(ethyl methacrylate), poly(n-butyl methacrylate), poly(i-butyl methacrylate), poly(t-butyl methacrylate), poly(n-octyl methacrylate), poly(2-ethyl hexyl methacrylate), poly(n-decyl methacrylate, poly(trifluoroethyl methacrylate) and poly(perfluorooctylethyl methacrylate). Examples of glycols suitable for the trans-esterification reaction are ethylene glycol, 1,2- or 1,3-propylene glycol, 1,2-, 1,3- or 1,4-butylene glycol, neopentylene glycol, 1,6-hexamethylene glycol, 1,8-octamethylene glycol, 1,10-decamethylene glycol, 1,12-dodecamethylene glycol, 1,2-dihydroxycyclopentane, 1,2- or 1,4-dihydroxycyclohexane, 1,2-dihydroxymethylbenzene, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, polybutylene glycol, polyethylene oxide/polypropylene oxide glycols, 1,4-dihydroxy-2,3-butene, 1,4-dihydroxymethylbenzene. Preferably, catalysts, known from the prior art, are used for the transesterification. Examples of such catalysts are alkyl titanate, such as butyl titanate or isopropyl titanate or the corresponding alkyl zirconates, furthermore stannates, such dialkyl tin acetate halide or dialkyl tin dialkyl esters, particularly dibutyl tin dilaurate, dibutyl tin diacetate and dibutyl tin acetate chloride. The catalysts are used in amounts of 0.5% to 2% by weight based on the polymethacrylate ester. Preferably, 0.5 to 1% by weight of catalyst are used. Yet another object of the invention is the use of the compounds as the only or partial glycol components for the synthesis of polyesters and polyurethane, as well as for the modification of alkyl and epoxide resins. Since the inventive compounds very precisely have a functionality of 2, they function exclusively as chain-extending polymeric blocks. Gelling due to higher functionality or chain termination due to monofunctionality is not observed. It is thus possible to synthesize block polymers or block copolymers, such as polyesters or polyurethanes with polymethacrylate blocks, which have particularly advantageous application properties. It is also of interest that reactive resins can be modified with the inventive polymers. In this connection, alkyd resins and epoxide resins are named primarily. It is, of course, also possible to form derivatives with one or both terminal hydroxyl groups and to obtain compounds by these means, which can be used directly as such or represent reactive intermediates. |
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| PATENT PHOTOCOPY | Available on request |
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