MXPA99002763A - Process for incorporating an active substance in a moulded plastic part - Google Patents

Abstract

Process for incorporating an active substance in an object partly or entirely consisting of a plastic, by bringing the object into contact with an active substance, the plastic of the object contains a dendrimer with terminal groups that are compatible with the plastic. The process is for example suitable for dying fibres.

Description

PROCEDURE TO INCORPORATE AN ACTIVE SUBSTANCE IN A PART OF PLASTIC MOLDED DESCRIPTIVE MEMORY The invention relates to a method for incorporating an active substance into an object that consists partially or completely of plastic, bringing the object into contact with the active substance. Said process is known from Kirk Othmer, Encyclopedia of Chemical Technology, Vol. 8 (1993), pp. 672-753. Here we describe the staining of plastic fibers in a bath containing a dye solution, in w the dye, in this case the active substance, penetrates the fiber. A drawback of the known method is that the active substance is with difficulty absorbed in the plastic. For example, it is not really possible to dye polypropylene fibers because the dye does not penetrate the polypropylene fiber or penetrates it only with great difficulty. The purpose of the invention is to provide a method that does not have the aforementioned drawback. Surprisingly, it has now been found that the active substance is very well absorbed if the plastic of the object contains a dendrimer with end groups w are compatible with the plastic.

A further drawback is that new combinations of active substances and plastics have become possible, because the active substances that are not absorbed in the plastic itself are absorbed in the plastic containing the dendrimer. The invention creates new surprising possibilities. For example, it is possible that a highly effective active substance w can not withstand the processing of the plastic in the object - for example because the active substance degrades at temperatures prevailing during the process - is incorporated into the plastic after processing. In the context of the invention, it is understood that the "Dendrimers" are oligomeric or polymeric, highly branched, three-dimensional molecules. The dendrimers according to the invention may contain a core, a number of generations of branches and terminal groups. A generation of branches consists of structural units ABx, in w x is > 2 or equal to two, w are radially joined to the core or to the structural units of the previous generation and extend outward. A subsequent generation can be formed because, for example, groups A react with groups B of the previous generation. The structural units can be the same with each subsequent generation (they repeat themselves) or they can differ. The dendrimers can be characterized by a degree of branching. The "degree of branching" of a dendrimer of a particular generation here is understands that it is the ratio of the number of branches present and the maximum possible number of branches in a fully branched dendrimer of the same generation. Branches can occur with varying degrees of regularity. The branches on the outer surface of the dendrimers used in the context of the invention may be, for example, of the same generation, but may also be of different generations. The latter may be, for example, the case if the synthesis of the dendrimers proceeds in a less controlled manner. In accordance with the invention, it is understood that the "dendrimers" are fully branched dendrimers, dendrimers with defects in their branched structure, dendrimers with an incomplete branching degree, asymmetrically branched dendrimers, star polymers, highly branched polymers, highly branched copolymers and / or block copolymers of highly branched polymers and not branched Preferably, the degree of branching is at least 50%, most preferably still at least 75%. Preferably it is made of fully branched dendrimers, dendrimers with defects in its branched structure, dendrimers with an incomplete branching degree, or asymmetrically branched dendrimers.

Due to the three-dimensional structure of the dendrimer, there are cavities between the branches. The shape and dimensions of these cavities vary according to the generation, the chemical composition of the structural units and the degree of branching. It is possible to influence the degree of branching and the shape and dimensions of the cavities between the branches during the preparation of the dendrimer. This can be achieved among other ways by varying for example the chemical composition, the molecular weight of the structural units, increasing or reducing the degree of branching or distributing the regularity in the composition of the branches. It is possible to influence the degree to which and the speed at which the active substance is absorbed in the molded part by varying the shape and dimensions of the cavities. The terminal groups of the dendrimers consist of the unreacted groups B of the structural units ABx. The end groups B can be by themselves compatible with the plastic of the molded part which is brought into contact with the active substance. If the end groups B are themselves incompatible, or insufficiently compatrible, with the plastic, the end groups B can be modified with the aid of a modifier compound to produce modified end groups which are compatible with the plastic. The fact that the end groups are compatible with the plastic means that the dendrimer can be well dispersed in the plastic.

If the plastic of the molded part is non-polar, a compound that is also non-polar is used as the modifying compound. If the plastic is polar, a compound that is also polar is used. The type of modifier compound to be used will depend to a large extent on the reactivity of the modifying compound with respect to the terminal group B of the dendrimer. Preferably, a compound is chosen that reacts as completely as possible with the terminal group of the dendrimer. Suitable modifying compounds for attaching non-polar groups to the terminal groups of the dendrimer are, for example, aliphatic halides, aliphatic alcohols, phenols, aliphatic and aromatic carboxylic acids, fatty acids, esters of aliphatic carboxylic acids and aromatic or aliphatic alcohols, esters of aromatic carboxylic acids, aliphatic or aromatic epoxides, aliphatic or aromatic isocyanates, aliphatic or aromatic amides, fully or incompletely fluorinated aliphatic compounds, sulfonic acids and sulfonic acid derivatives, phosphorus-containing compounds or silicon-containing compounds. Mixtures of said compounds are also suitable. Preferably a compound that modifies the terminal group with an alkyl group is used as a non-polar compound, because this generally results in very good compatibility with non-polar plastics, such as polyolefins. examples of modifying compounds that modify terminal groups with an alkyl group are fatty acids, alcohols derived from a fatty acid, amines derived from a fatty acid, isocyanates corresponding to a fatty acid, epoxides corresponding to a fatty acid and halogenides corresponding to a fatty acid. Examples of these are stearyl alcohol, dodecylphenol, 4,4,5,5,5-pentafluoro-n-pentanol-1, stearamide, palmityl isocyanate, palmitoyl chloride, stearyl chloride, pentafluoropropionyl chloride, lauric acid, acid Myristic, palmitic acid, stearic acid, perfluorononanoic acid and the mixture of alkanocarboxylic acids known as "Montanwachs". Most preferably a known saturated or (mono- or poly) unsaturated fatty acid is used. Preferably a modifier compound is used which modifies the terminal group with an alkyl group having 6-50 carbon atoms, most preferably with an alkyl group having 12-30 carbon atoms, most preferably still with an alkyl group having 16- 20 carbon atoms. Other compounds suitable for modifying the end groups with non-polar groups are chains of oligomers and / or polymers which are compatible with the plastic matrix in which the dendrimer is to be mixed. Suitable compounds for modifying the terminal groups of the dendrimer with polar groups are for example polyacrylates, polymethacrylates, polyvinyl alcohols, polyvinyl esters, polyvinyl ethers, polyurethanes, polyurea, polyisocyanates, polyvinylpyridines, polyvinylpyrrolidones, polyethylene glycols, polyethylene imines, polycarbonates, polycaprolactones, nylons, styrene-acrylonitrile copolymers (SAN), styrene-maleic anhydride copolymers (SMA), polyethylene oxides (PPO). Jeff amines, telechelic polyesters, copolymers of alkenes with carbon monoxide, styrene copolymers, acrylic acid polymers and methacrylic acid polymers. Preference is given to using dendrimers of which at least 30% of the terminal groups have reacted with a modifying group, most preferably 40-75% of the end groups reacted with a modifying compound. This ensures that the dendrimer is miscible in the plastic of the object and that the active substance is rapidly absorbed. Regular compounds can be prepared dendrimers through a divergent method, according to which successive generations of dendrimer molecules are generated in repeated reaction sequences starting from a multifunctional core, the branches being generated in a systemic manner. Said process is described for example in EP-A-575 596. It is also possible to first synthesize regularly branched segments through a convergent process and to couple them to a multifunctional core in the last step. In addition, it is possible to use combinations of convergent and divergent procedures. Dendrimers less regularly composed can be prepared, for example, by polycondensation, ring opening polymerization or addition polymerization.

Highly branched polymers can be prepared, for example, by radical or anionic or cationic chain polymerization of type AB monomers, wherein A is a vinyl group and B a group that is activated through an initiation commonly used for copolymerization of chain. Said polymerization is described, for example, in J.M.J. Fréchet, Science 269 (1995), pp. 1080-1083. It is also possible to prepare a highly branched polymer by cationic polymerization of ethyleneimine. The resulting highly branched polymer has many functional end groups. The dendrimers which are suitable in the context of the invention are dendrimers based, for example, on a polyester, polyether, polythioether, polyamide, polyetherketone, polyalkyleneimine, polyamidoamine, polyetheramide, polyarylene, polyalkane, aromatic polyalkene compounds, polyarylacetylene and / or a dendrimer containing phosphorus or silicon, or a combination thereof. Preferably a denerimer based on polyalkyleneimines or polyamidoamine is used. It is also possible to use a highly branched polyether. When dendrimers according to the invention are used with which genera and branches are demonstrable, dendrimers of the second generation onwards are preferably used, including the 5th, most preferably the 3rd. or the 4th Active substances that can be used in the process according to the invention are, for example, antistatic agents, adhesives, odorous substances, fireproofing agents, flame retardants, antioxidants, UV stabilizers and dyes. Preferably dyes are used. To accelerate the incorporation of the ctiva substance a low molecular weight compound can be used which swells the plastic. Examples of suitable types of dyes are azo, azine, perinone, anthraquinone, xanthene, phthalocyanine, triarylmethane, indophenol, coumarin and diazomethane dyes. Mixtures of dyes are also suitable. The criteria in the selection of the dye are, for example, the desired color and the UV and thermal resistance of the pigment. Using the process according to the invention, the active substances can be incorporated into objects of many types of plastics. Thermoplastics, thermofixation plastics as well as rubbers are suitable. The invention is suitable for both homopolymers and copolymers. You can also use mixtures of plastics. Examples of suitable plastics are polyolefins, such as low density polyethylene (LDPE), high density polyethylene (HDPE), vLDPE, LLDPE, polypropylene (PP), which is understood to include PP homopolymers and PP copolymers with such a phase such as random ethylene / propylene copolymers and block copolymers of PP with ethylene / propylene phase, polymers of vinyl, styrene polymers, acrylic polymers, fluorine-containing polymers, polyamides, polycarbonates, polyoxyalkylenes, polyimides, polibencilimidazoles, polyphenylene oxides, polyacrylonitriles, polyesters, phenol-formaldehydes, aminoplastics, epoxy resins, polyurethanes, rubber, styrene-butadiene rubber butyl, chlorobutyl rubber, rubber, chloroprene rubber, nitrile rubber, butadiene rubber sopreno, rubbers of ethylene-prolileno (EPM, monomer ethylene-propylene and EPDM, monomer ethylene-propylene-diene) rubbers of silicone, urethane rubbers, acrylate rubbers, fluorine-containing rubbers and / or cyclopentene rubbers. In the method according to the invention, the object can be brought into contact, in various ways, with the active substance. For example, it is possible to immerse the object or to coat it with a liquid active substance or to treat the object in this way with a solution, a molten bath, a suspension or an emulsion of an active substance. It is also conceivable that an object is brought into contact with a gaseous active substance or with an active substance in the solid phase. In a preferred embodiment, the invention relates to a process in which a polyolefin, most preferably polypropylene, is used as the plastic of the object. By preference, the plastic of these objects comprises polypropylene imine dendrimers. By preference, the dendrimer contains non-polar fatty acid end groups.

Said object can be printed very well with the aid of the process according to the invention, without having to subject the surface of the object to a special treatment, such as corona discharge treatment. These objects can also be dyed well by immersing them in a bath containing a dye solution. In this way, polyolefin objects can be obtained with very deep intense colors, while it can not be achieved or can be achieved with great difficulty with known methods. The advantages of the invention become particularly evident if the process according to the invention is used in dyeable fibers, in particular polypropylene fibers. In particular, dyeable fibers, especially polypropylene fibers, in accordance with known processes involve problems, in connection with the poor absorption of the dye in the fibers. It is not possible to modify the surface of the fibers to improve dye absorption, such as by etching the surface of the fiber, because these modifications of the fibers generally adversely affect the mechanical properties of the fibers, such as strength to the tension and rigidity. The fibers that have been dyed with the aid of the process according to the invention can have bright, deep colors and there are no problems with the mechanical properties of the fibers. By Preference for dyeing the fibers, a polar dye is used which can not be dissolved in water. Examples of such dyes are disperse dyes. In this way, fibers having high resistance to washing are obtained. The invention will be elucidated with reference to the examples, without being restricted thereto. In the following examples, polypropyleneimine dendrimers are used. The preparation of such dendrimers is described in EP-A_575 596 and EP-A-707 611. polypropyleneimine dendrimers amino terminal in accordance with the aforementioned applications have 16 amino terminal groups in the third generation and 32 amine end groups in the fourth generation.

EXAMPLE I 4. 84 grams of a dendrimer terminal amino polypropyleneimine of the fourth generation (corresponding to 44.0 milliequivalents of NH2), 12.50 grams of stearic acid (corresponding to 43.9 milliequivalents) and 20 ml of xiieno stirred and heated to 180 ° C for one hour in a three neck flask with a volume of 250 ml. The three neck flask was first equipped with a Dean-Stark apparatus with reflux cooler. Then, the xylene solution was emptied into 250 ml of methanol while it was still hot, which resulted in the formation of a precipitate. The precipitate was removed by filtration, washed with methanol and dried in a vacuum at 45 ° C. The yield was 12.8 grams of a yellowish white powder. The infrared and nuclear spin resonance showed that all amino groups of the dendrimer have been converted to amide by stearic acid. The dendrimer modified with stearic acid had a melting point of 82-83 ° C. In a mini-extrusion apparatus, a mixture of 4.5 g of an isotactic polypropylene with a melt index of 20 g / 10 min (230 ° C, 2.16 kg) and the dendrimer was successfully extruded in amounts of 1, 2 and 4% in weight. A strand was obtained through the drain opening of the extruder, which was stretched through a fast rotating winder to obtain fibers with a thickness of about 70 microns.

EXAMPLE II 4. 24 grams of an amino terminal polypropyleneimine dendrimer of the fourth generation (corresponding to 38.6 milliequivalents of NH2) and 5.48 grams of stearic acid (corresponding to 19.3 milliequivalents, that is, half the number of amino groups used) were heated to 150 ° C for one hour, at a reduced pressure of 20 mm of mercury, in a 250 ml two-necked flask equipped with a distillation apparatus with a cooler. After cooling it had formed a yellow-white solid substance which, as demonstrated by spectroscopic examination, no longer contained free stearic acid and had a melting point of 74-76 ° C. The polypropylene fibers were prepared as described in Example I.

EXAMPLE III . 56 grams of an amino terminal polypropyleneimine dendrimer of the third generation (corresponding to 100.2 milliequivalents of NH2) and 28.44 grams of stearic acid (corresponding to 100.0 milliequivalents) were heated at 150 ° C for one hour, at a reduced pressure of 20 mm of mercury, in a 250 ml two-necked flask equipped with a distillation apparatus with a cooler After cooling, a yellow-white solid substance had formed which no longer contained free stearic acid. The product had a melting point of 81-82 ° C. The polypropylene fibers were prepared as described in Example I.

EXAMPLE IV 14. 19 grams of an amino terminal polypropyleneimine dendrimer of the third generation (corresponding to 134.6 milliequivalents of NH2) and 19.11 grams of stearic acid (corresponding to 67.2 milliequivalents, that is, half the number of amino groups used) were heated to 150 °. C for one hour, at a reduced pressure of 20 mm of mercury, in a 250 ml two-necked flask equipped with a distillation apparatus with a cooler. After cooling, a yellow-white solid substance had formed which no longer contained free stearic acid. The polypropylene fibers were prepared as described in Example I.

COMPARATIVE EXPERIMENT A Polypropylene fiber was obtained without a modified dendrimer added through extrusion at 220 ° C of the polypropylene used in Example I, otherwise as described in Example I.

EXAMPLE V An acid dye bath containing the Tectilon blue dye GC-G (Acid Blue 344) was prepared by dissolving 1 gram of this dye in a solution of 2.8 ml of concentrated sulfuric acid in 1 liter of water, which had a pH of about 1.6. Packs of polypropylene fibers with a length of about 50 mm, prepared according to examples I-IV and Comparative Experiment A, were placed in 10 ml of the dye solution. While the solution was stirred by means of a magnetic stirrer, it was set at 80 ° C in a water bath in about 30 minutes and kept at this temperature for two hours. Then, the bundle of fibers was removed from the dye solution and washed twice in tap water at about 20 ° C for about 10 seconds, then the bundle of fibers was air dried. The amount of dye absorbed by the fibers was evaluated visually. In this evaluation, the following designations were assigned: 0 colorless, the same as the starting material 1 light coloration 2 moderate coloration 3 deep coloration 5 very deep coloration These results of color evaluations of the different fibers are shown in Table 1.

TABLE 1 Color evaluation of fibers stained with Tectilon blue GC-G (Acid blue 344) Fiber according to Comparative Experiment A: 0. This shows that the results obtained with the fibers prepared from the compositions according to the invention are considerably better than those obtained with fibers made of polypropylene without the added modified dendrimer. The best results are obtained with fibers prepared from the composition according to example II, in which 50% of the end groups of the dendrimer are modified.

EXAMPLE VI The procedure according to Example VI was repeated using the Tectilon blue dye 4R-01 (Ciba-Geigy). The evaluation of the color of the resulting fibers is given in Table 2.

TABLE 2 Evaluation of the color of the fibers stained with tectilon blue 4R-01 Fiber according to Comparative Experiment A: 0. Half of the deeply colored fiber bundle containing 4% dendrimer modified according to Example II, was placed in 10 ml of 40 ° C water for 2 hours, with stirring . After! drying, the visual evaluation of the dye was invariable.

EXAMPLE VII The procedure according to Example V was repeated with Tectilon Red Blue 2B dye (Ciba-Geigy). The visual evaluation of the coloring is given in Table 3.

TABLE 3 Evaluation of the color of the fibers stained with Tectilon Rojo 2B blue.

Fiber according to Comparative Experiment A: 0. Half of the deeply colored fiber bundle containing 4% dendrimer modified according to example II, was placed in 10 ml of 40 ° C water for 2 hours, with stirring . After drying, the visual evaluation of the dye was invariable.

EXAMPLE VIII The procedure according to Example V was repeated using Tectilon 2G 200 yellow dye and Erionyl RL blue dye. The coloration of the fibers containing 2 and 4 weight percent dendrimer according to examples 2 below and including 4 was very deep. A moderate to deep coloration was obtained with 1% of the dendrimer. No loss of color occurred in the 40 ° C water treatment as described in Example VIII of the deeply colored fibers containing 4% dendrimer according to Example II.

EXAMPLE IX An acid dye bath containing the red dye "B" Erionyl was obtained by dissolving 1 gram of this dye in one liter of a solution of acetic acid in water with a pH of 3.1. The fibers were stained in the manner described in Example VIII. The visual evaluation of the coloration is given in Table 4. No loss of color occurred in the water treatment of 40 ° C as described in Example VI of the deeply colored fibers containing 4% dendrimer modified according to the example II.

TABLE 4 Evaluation of the color of the fibers stained with Erionyl 2B Red in dilute acetic acid Fiber according to Comparative Experiment A: 1.

EXAMPLE X A bath of disperse dye was prepared by dispersing 1 gram of the blue dye Terasil 3RL-02 in one liter of water. Polypropylene fibers prepared according to examples II and IV were stained in this bath, according to the procedure as described further in example V. The coloration of the fibers, comprising 2% by weight of dendrimer, was very deep .

The resistance to washing was determined by treating a pack of 10 fibers with 0.5% by weight of soap solution for 45 minutes at 50 ° C according to ISO 105. There were no color differences before and after the treatment of the fibers.

Claims (13)

NOVELTY OF THE INVENTION CLAIMS

1. - A method for incorporating an active substance in an object that consists partially or completely of plastic, bringing the object into contact with the active substance, characterized in that the plastic of the object contains a dendrimer with terminal groups that are compatible with the plastic.

2. The process according to claim 1, further characterized in that a fully branched dendrimer, a dendrimer with defects in its branched structure, a dendrimer with an incomplete branching degree or an asymmetrically branched dendrimer is used as the dendrimer.

3. The process according to claim 1 or claim 2, further characterized in that the end groups of the dendrimer have been modified with a modifying compound to produce modified end groups that are compatible with the plastic.

4. The process according to claim 3, further characterized in that the modifying compound modifies the terminal group with an alkyl group.

5. - The method according to claim 4, further characterized in that the alkyl group has 6-50 carbon atoms.

6. The process according to any of claims 3-5, further characterized in that at least 30% of the terminal groups have reacted with the modifying compound.

7. The process according to any of claims 1-6, further characterized in that a dendrimer of the second generation is used, including the 5a.

8. The method according to any of claims 1-7, further characterized in that the polypropylene is used as the plastic of the object.

9. The process according to any of claims 1-8, further characterized in that the fibers are used as molded parts.

10. The method according to claim 8 or 9, further characterized in that a polypropylene imine dendrimer is used in the plastic of the object.

11. The process according to claim 10, further characterized in that the dendrimer contains non-polar fatty acid end groups.

12. A molded part for use in the method according to any of claims 3-8.

13. - A plastic composition of the molded plastic part for use in the process according to any of claims 3-8.