X-RAYS. Field of the invention. The application relates to the use of iodobenzoic acid derivatives for the production of plastic opaque molded bodies, as well as to synthetic materials, to synthetic molding compositions and to plastic molded articles containing synthetic materials. minus a derivative of iodobenzoic acid. Description of the prior art. Transparent synthetic molded bodies with good mechanics for the medical sector and for children's toys are sought so that they can be detected in the body by means of X-ray tests. Furthermore, these materials must have sufficient light stability at least for the employment inside buildings. The molded bodies, commercially available, based on polycarbonates, are not suitable for this purpose since their contrast in the radiographs is very small. Therefore, an attempt has been made to combine the polycarbonates with X-ray contrast agents containing barium or bismuth. However, these contrast agents are not sufficient for toxicological reasons as well as due to their modifying effect on the mechanical and optical properties of the commercially available polymers. Nor does the use of iodine-containing compounds as described in publications US-3 469 704, DE-A-17 20 812, GB-A-11 63 816, US-3 382 207 and US-3 535 300, in molding compositions or molded bodies fulfill the desired profile of properties for applications in medicine and in parts for
REP: 136061 In this way it has been observed, for example, that molding compositions of this type or castings become reddish after a few weeks under ambient lighting and / or have poor mechanical properties and / or they have a reduced thermal stability and / or contain a too low proportion of iodine, so that they can be detected on the radiograph. Detailed description of the invention. The task of the invention therefore consists in making available opaque agents to X-rays that do not adversely affect the material properties of the synthetic products. It has now been found, surprisingly, that iodobenzoic acid derivatives meet the desired profile of demands. Even with small amounts of iodobenzoic acid derivatives, moldings can be produced which are detectable by means of X-rays. The object of the present application therefore consists in the use of iodobenzoic acid derivatives as opaque agents to X-rays, especially in synthetic materials, especially for transparent synthetic materials, as well as synthetic materials, masses of synthetic materials and bodies molded of synthetic materials containing at least one ester of iodobenzoic acid. The iodobenzoic acid derivatives according to the invention are amides, alkylamides, dialkylamides and, especially, esters. Preferred are esters and amides which are manufactured from monovalent or polyvalent, aliphatic or aromatic alcohols or amines. Alcohols and aliphatic amines are, by way of example and preferred, alcohols and amines with 1 to 30 carbon atoms. Chain
It can be linear or it can be branched. The carbon chain can contain one or several alcohol or amine functionalities, the alcohol or amine functionality can be found at any point of the carbon chain. Optionally, the alcohol can also be halogenated. Preference is given to esters based on methane, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, tere. -butanol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-l-butanol, 2-methyl-2-butanol, 3-methyl-l-butanol, 3-methyl-2-butanol, 2,2 - dimethylpropanol, hexanol, heptanol, octanol, nonanol, decanol, undecanol, dodecanol, tridecanol, tetradecanol, pentadecanol, hexadecanol, heptadecanol, octadecanol, as well as, if appropriate, its structural isomers, 1,2-ethylene glycol, trimethylolmethane, pentaerythritol, 1,2-propanediol and 1,3-propanediol. In the case of the polyhydric alcohols, mixed ethers are also suitable according to the invention, for example partly with an iodobenzoic acid and partly with another acid, or incompletely esterified compounds. Aromatic alcohols are, especially, phenols and bisphenols. The iodobenzoic acid derivatives can be halogenated, in addition to iodine, also with F, Cl or Br. Preference is given to the non-halogenated monoiodobenzoic acid derivatives, with 4-iodobenzoic acid derivatives being particularly preferred. Mixtures of various iodated benzoic acid derivatives are also suitable according to the invention. The iodobenzoic acid derivatives are known or are prepared according to known methods. The iodobenzoic acid derivatives will be added to the synthetic materials, preferably in amounts from 0.001 to 20% by weight, preferably from 1 to 6% by weight. Preferably, synthetic materials are thermoplastics, especially transparent thermoplastics, preferably polymers of ethylenically unsaturated monomers and / or polycondensates of reactive, bifunctional compounds. Mixtures of various synthetic materials are also possible within the meaning of the invention. Especially suitable synthetic materials are polycarbonates or copolycarbonates based on diphenols, polyacrylates or copolyacrylates and polymethacrylates or copolymethacrylates such as, for example, and preferably polymethyl methacrylate, polymers or copolymers with styrene. as, by way of example and preferred, transparent polystyrene or polystyrene acrylonitrile (SAN), transparent thermoplastic polyurethanes, as well as polyolefins, such as, by way of example and preferably, transparent polypropylene types or polyolefins based on cyclic olefins (for example TOPAS® , Hoechst), polycondensates or copolycondensates of terephthalic acid, such as, by way of example and preferred, polyethylene terephthalate or copolyethylene terephthalate (PET or CoPET) or glycol-modified PET (PETG). Polycarbonates or copolycarbonates, especially polycarbonates and / or non-halogenated copolycarbonates having molecular weights M w of between 600 and 100 000, preferably between 2000 and 80 000, particularly preferably between 18 000 and 40 000, are particularly preferred. thermoplastic, aromatic polycarbonates, in the sense of the present invention, are both homopolycarbonates and also copolycarbonates; the polycarbonates can be linear or can be branched in a known manner.
The polycarbonates can also be wholly or partially brominated. The production of these polycarbonates is carried out in a known manner from diphenols, carbonic acid derivatives, if appropriate chain terminators, if appropriate, branching agents. Details relating to the manufacture of polycarbonates have been indicated in many patent descriptions since approximately 40 years ago. By way of example only reference will be made to Schnell's publications, "Chemistry and Physics of Polycarbonates", Polymer Reviews, Volume 9, Interscience Publishers, New York, London, Sydney 1964 by D. Freitag, U. Grigo, P.R. Müller, H. Nouvertne ', BAYER AG, "Polycarbonates" in Encyclopedia of Polymer Science and Engineering, Volume 11, Second Edition, 1988, pages 648-718 and finally by Drs. U. Grigo, K. Kircher and P.R. Müller "Polycarbonate" in Becker / Braun, Kunststoff-Handbuch, Volume 3/1, Polycarbonate, Polyacetale, Polyester, Celluloseester, Cari Hanser Verlag Munchen, Vienna 1992, pages 177-299 The preferred diphenols for the preparation of polycarbonates are: , 4'-dihydroxydiphenyl, 2,2-bis- (4-hydroxyl) -propane, 2,4-bis- (4 * hydroxyphenyl) -2-methylbutane, 1, 1-bis- (4-h) ? droxifen? l) -p-dnsopropylbenzene, 2,2-bis- (3-methyl-4-hydroxyphenyl) -propane, 2,2-bis- (3-chloro-4-hydroxyphenyl) -propane, bis- (3,5-dimethyl-4-hydroxymethyl) -methane, 2,2-b? s- (3,5-d? methyl-4-hydroxyphenyl) -propane, bis- (3, 5) -dimethyl-4-hydroxyphenyl) -sulfone, 2,4-b? s- (3,5-d? methyl-4-hydrox? phenyl) -2-methylbutane, l, l-bis- (3.5 - d? methyl-4-hydroxypheni?) - p-diisopropylbenzene, 2,2-bis- (3,5-dichloro-4-hydroxyphenpropane, 2,2-b? s- (3,5-d? bromo-4-hydroxyphenol) -propane yl, l-bis- (4-hydroxyphenyl) -3,3,5-tpmethylcyclohexane The diphenotes especially preferred are 2,2-bis (4- hydroxyphenyl) -propane, 2,2-bis- (3,5-dimethyl-4-hydroxyphenyl) -propane, 2, 2-bis- (3, 5-dichloro-4-hydroxyphenyl) -propane, 2,2-bis- (3,5-dibromo-4-hydroxyphenyl) -propane, 1,1-bis- ( 4-hydroxyphenyl) -cyclohexane yl, l-bis- (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane. Preferred branching agents are triphenols, (trichloride) trime-sine acid, cyanuric trichloride and 3,3-bis- (3-methyl-4-hydroxyphenyl) -2-oxo-2,3-dihydroindole. It is possible and convenient for achieving improved compositions of synthetic materials that at least one other additive usually present in the thermoplastic synthetic materials is incorporated, preferably in the polycarbonates and copolycarbonates, such as, for example, stabilizers (such as those have described, for example, in EP 0 839 623 Al or EP 0 500 496 Al) especially thermostabilizers, in particular hindered organic phenols, hindered amines (HALS), phosphites or phosphines, for example and preferably trifenilphosphine; demolding, for example and preferably fatty acid esters of glycerin or tetrametanolmethane, the unsaturated fatty acids, in particular ghcerin monostearate or pentaerythritic tetrastearate (PETS), flameproofing agents, antistatics, absorbers, etc., can be completely or partially epoxidized. UV, for example and preferably hydroxybenzotriazoles and hydroxytpaz ina, fillers, foaming agents, dyes, pigments, optical brighteners, transesterification catalysts and nucleating agents and the like, preferably in amounts, respectively, of up to 5% by weight, preferably from 0.01 to 5% by weight, weight referred to the mixture as a whole, particularly preferably from 0.01% by weight to 1% by weight, based on the mixture of the synthetic material.
The incorporation of the iodobenz acid esters as well as, where appropriate, the additives or mixtures of the additives, is generally carried out in a conventional manner, for example before or during the polymerization or by further mixing with the material synthetic, preferably by extrusion. The compositions of synthetic material, obtained in this way, are generally presented in the form of solutions, dispersions, emulsions, fine powders, powders, granules, platelets or flakes (molding compositions) and are used for the production of molded articles (moldings). The production of the molded bodies of synthetic material is carried out according to conventional methods such as, for example, hot pressing, spinning, extrusion or injection casting. The synthetic material compositions according to the invention contain, in general, from 0.01 to 10% by weight, preferably from 1 to 3% by weight, of organic linked iodine. The molded objects are preferably transparent objects, especially for applications in medicine, such as, for example and preferentially, probes or pieces for joints or as small objects that are used by children. Obviously, customary molded objects such as sheets, tapes, plates, ribbed plates, multi-ribbed plates, containers, tubes and other profiles can also be manufactured with the compositions of plastics according to the invention. The synthetic compositions can also be processed to cast sheets. It is also interesting to use the compositions of synthetic material according to the invention for the production of multilayer systems. In this case, the synthetic material composition according to the invention will be arranged in a coated layer on a molded object constituted by a synthetic material that is not opaque to X-rays. The application can be carried out simultaneously or immediately after molding of the molded body, for example, coextrusion or injection of several components. However, the application can also be carried out on the molded, finished base body, for example by rolling with a film or by coating with a solution. Preferably, for the manufacture of small parts, which are used by children, especially for the manufacture of toys such as construction parts, the compositions of synthetic material containing iodobenzoic acid esters will be used. The following examples serve to explain the invention. The invention is not limited by the examples. The indications in percentage and in parts then mean parts by weight or percentages by weight. Example 1. 29.3 parts of 4-iodobenzoyl chloride (Aldrich) are dissolved in 100 parts of pyridine. Subsequently, 3.1 parts of ethylene glycol (Aldrich) are added dropwise with stirring. After 10 minutes, it is heated for 1 hour at 75 ° C. The product is then taken up in methylene chloride, washed with water as well as in an acidic and basic state and dried. Diester yields of 98.7% of the theory are obtained. The melting point of the colorless compound was 146 ° C. Example 2: 95.5 parts of unstabilized polycarbonate, free of additives, are amassed, with an average molecular weight of approximately 30,000 (Mw according to the GPC), vi. Hscosity in solution:? = 1,293 (Makrolon 2808®, from Bayer AG) together with 0.3 parts of PETS and 4 parts of 1,2-ethylene glycol bis-4-iodobenzoate (from example 1) at 300 ° C with a twin extruder spindle and then injected to give platelets for color sample (155 mm x 75 mm x 2 mm).
Example 3 Platelets for color samples of Example 2 are tested for light stability by irradiation with a UV lamp, by a Xe-WOM lamp and by daylight. The results are shown in Table 1. Table 1. Stability in light of samples of Example 2 with a thickness of 2 mm.
fifteen
twenty
Example 4. 4 parts of ethylene glycol b-s-4-iodobenzoate (from example 1) are dissolved with 96 parts of pohmethyl methacrylate (Plexiglas®) in 150 parts of sodium chloride.
Methylene and are transformed to give a film with a thickness of 180 μm and vacuum. The film is then illuminated for 8 hours under a UV lamp at 254 nm. At first sight, no modification can be observed. In addition, the VIS spectra between 400 and 1200 nm are identical before and after irradiation with UV in the field of measurement accuracy. Example 5, 13.3 g of 4-iodobenzoyl chloride are dissolved in 30 ml of dichloromethane and 4 ml of pyridine. 6.5 g of dithylamine are slowly added dropwise to the solution and the mixture is stirred for a further 30 minutes at room temperature. The reaction mixture is washed with water, with 10% strength sodium hydroxide solution. , with 10% hydrochloric acid and boiling with water, drying over sodium sulfate and then concentrating by evaporation. Yield 18 g of light yellow crystals. The product can be melted at 320 ° C with polycarbonate without coloring. Example 6 A sheet is manufactured by casting from Makrolon 2808 with 5% of the product of Example 5 with the aid of methylene chloride. The film is transparent and colorless When the film is illuminated with a UV lamp up to 254 nm for 14 hours, no coloration can be observed with the naked eye. Comparative Example 1. 161.1 g (0.11 mol) of oligo- [2,2-bis- (4-hydroxyphenyl) -propanecarbonate] ester of chlorocarbonic acid are dissolved (approximate polymerization degree 5)
(manufactured according to U. Grigo, K Kirchner and P.R. Müller "Polycarbonate" in Becker /
Braun, Kunststoff-Handbuch, Volume 3/1, Polycarbonate, Polyacetale, Polyester, Celluloseester, Cari Hanser Verlag München, Vienna 1992, page 143 formula adds, at 20-25 ° C, under agitation, a clear solution constituted by 89.1 g (0.189 mol) of 2,4,6-triiodophenol, 35.6 g (0.40 mol) of 45% sodium hydroxide solution and 800 g of water. After 5 minutes, 0.71 g of N-ethylpiperidine are added and the mixture is stirred vigorously for 30 minutes. The dichloromethane phase is separated from the aqueous phase and washed until the absence of electrolytes. The solvent is removed by evaporation and the solution, concentrated by evaporation, is dried at 120 ° C under vacuum of the water pump. Yield: 202 g of solid product and chlorine. Analysis: Phenolic OH: 160 mg / kg, Saponifiable Cl: < 0.2 mg / kg. Iodine content - approximately 27%. When the samples are heated in a crucible together with polycarbonate at 300 ° C for 5 minutes, no coloration is observed. Comparative Example 2. 94.7 parts of polycarbonate (Makrolon 2808®, Bayer AG) are kneaded together with 5.9% by weight of iodated oligocarbonates of comparative example q (end groups of triiodophenol) and 0.5% by weight of agent for PETS demolding
(Pentaeprite tetrastearate) at 280 ° C with a twin-screw extruder and then injected to give specimens of varying thickness. The transparency of these molded bodies was, respectively, greater than 85%. The ability to detect X-rays was shown in test pieces with a thickness of 1.2 - 3.2 mm with the usual parameters in the field of medicine.
with a thickness of 2 mm of comparative example 2:
^
10
Comparative Example 3. 94.7 parts of Makrolon 2808® are kneaded together with 0.3 parts of PETS and
15 parts of 4,4'-d? Iodobifen? L (Aldrich) at 280 ° C with a twin screw extruder and then injected to give specimens with variable thicknesses The transparency of this molded body was, respectively, greater than 85% Samples with a thickness of 2 mm are subjected to the action of weathering under Xe-WOM 0.35 W / m2 without spraying with rain Previously colorless samples were intensely colored red later When a test tube was illuminated of that type with a UV lamp of 254 nm for 8 hours could also generate a reddish coloration clearly visible
Comparative Example 4. 25 9.87 g (0.067 mol) of ol? Go- [2,2-b? S- (4-h? Drox? Feml) - are dissolved.
< (Própanocarbonatojéster chlorocarbonic acid (Comparative Example 1) in 56 g of dichloromethane. Is added, at 20-25 ° C, with stirring, a clear solution consisting of 2.48 g (0.01 mol) of 4 -yodobenzoico, 1.33 g (0.015 mole) of sodium hydroxide lye 45% and 72 g of water. after 5 minutes 5 added 0.084 g of N-ethylpiperidine and stirred vigorously for 30 minutes. The phase Dichloromethane is separated from the aqueous phase and washed until electrolyte is absent.The solvent is removed by evaporation and the concentrated solution is evaporated to 120 ° C under vacuum of the water pump, yield: 9.7 g of product colorless solid 10 Analysis: phenolic OH: 0.09%, saponifiable Cl: 3 ppm, iodine content: approximately 4.6% When the samples are heated in a crucible together with polycarbonate a
300 ° C for 5 minutes no coloration is observed. The iodine content is too small to obtain, analogous to the example
Comparative 2 mixtures with polycarbonate with an amount of iodine detectable on X-rays. Comparative example 5. A film is prepared in solution consisting of 50 parts of Makrolon 3208, 50 parts of the oligomer according to comparative example 4 and 0.5 parts of 20 Tinuvin 234. The film does not show coloration even after 6 hours of illumination under a UV lamp (254 nm). Comparative Example 6. 23 parts of BPA are reacted with 17 parts of phosgene and 21 parts of 2,3,5-iodobenzoyl chloride under boundary surface conditions between
25 phases (according to WO 9859005) to give an oligomer with 2,3,5- end groups
• to show in a crucible together with polycarbonate, at 300 ° C, for 5 minutes, a clear reddish coloration is observed. Comparative Example 7. 6 parts of 4-iodobenzoic acid with 94 parts of polycarbonate in a crucible are heated for 5 minutes at 300 ° C The 4-iodobenzoic acid partly follows by sublimation over the crucible are heated Comparative Example 8. 4 parts of 3,5-diiodoalicylic acid with 96 parts of polycarbonate in a crucible for 5 minutes at 300 ° C The mixture is clearly colored in red Comparative example 9. Heat up 4 parts of the 2,3,5-triiodobenzoic acid with 96 Polycarbonate parts in a crucible for 5 minutes at 300 ° C. The mixture was clearly colored red Comparative Example 10. It is manufactured by a film coating solution consisting of 96 parts of Makrolon 2808 and 4 parts of 1,4-diyodotetraf úorbenceno (Aldrich) After drying the colorless and transparent film lights , durapte6horasc munalánparadeUVa254rarL then one will be recognized reddish colorarión comparative Example 11. 6 parts of iohexol (Signa) with 94 parts of policaibonato are heated in a crucible for 5 minutes at 300 ° C Sie strong roducsum? loración it is noted that, with In relation to this date, the best method known by the applicant to carry out the aforementioned invention is that which results from the present description of the invention