Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J13/00—Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
  • B01J13/02—Making microcapsules or microballoons
  • B01J13/20—After-treatment of capsule walls, e.g. hardening
  • B01J13/22—Coating
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J13/00—Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
  • B01J13/02—Making microcapsules or microballoons
  • B01J13/06—Making microcapsules or microballoons by phase separation
  • B01J13/14—Polymerisation; cross-linking
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
  • Y10T428/2982—Particulate matter [e.g., sphere, flake, etc.]
  • Y10T428/2984—Microcapsule with fluid core [includes liposome]
  • Y10T428/2985—Solid-walled microcapsule from synthetic polymer
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
  • Y10T428/2982—Particulate matter [e.g., sphere, flake, etc.]
  • Y10T428/2984—Microcapsule with fluid core [includes liposome]
  • Y10T428/2985—Solid-walled microcapsule from synthetic polymer
  • Y10T428/2987—Addition polymer from unsaturated monomers only
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
  • Y10T428/2982—Particulate matter [e.g., sphere, flake, etc.]
  • Y10T428/2989—Microcapsule with solid core [includes liposome]

Definitions

• the present invention relates to microcapsules comprising a capsule core, a capsule wall and disposed on the outer surface of the capsule wall polyelectrolytes having an average molecular weight of 500 g / mol to 10 million g / mol, wherein the capsule wall is constructed
• microcapsules each based on the total weight of the monomers, wherein the microcapsules have an average particle size of 1, 5 - 2.5 microns and 90% of the particles have a particle size ⁇ 4 microns.
• the present invention relates to a process for their preparation, their use in textiles, binders and heat transfer fluids and microcapsules as an intermediate.
• PCM phase change material
• EP 1 029 018 teaches the use of microcapsules having a capsule wall of a highly crosslinked methacrylic acid ester polymer and a latent heat storage core in bonding building materials such as concrete or gypsum.
• DE-A-101 39 171 describes the use of microencapsulated latent heat storage materials in plasterboard.
• WO 2005/1 16559 teaches the use of microencapsulated latent heat storage materials in chipboard together with melamine-formaldehyde resins as binders. In the construction sector, it is often advantageous to use larger microcapsules, since they are usually less dusty or can be processed more advantageously with other additives. Other requirements, however, the textile sector.
• Microcapsules which are to be spun together with the fiber mass must be sufficiently small so that the fibers do not become brittle and can be processed in the spinning process.
• the microcapsule powder taught in EP-A-1 029 018, WO 2005/1 16559, and DE-A-101 39 171 has mean particle sizes in the range from 2 to 25 ⁇ m. The size of the powder particles corresponds to the capsule sizes in the microcapsule dispersions.
• EP-A 1 321 182 teaches microencapsulated latent heat storage materials with a capsule wall of a highly crosslinked methacrylic acid ester polymer and also mentions their use in textiles. Teaching this document are microcapsule dispersions with a particularly low proportion of capsules of particle size ⁇ 4 microns.
• EP-A 1 251 954 teaches polymethacrylic acid-based microcapsules with particle sizes of 1.2 ⁇ m for the impregnation of fibers. Small capsules, however, often show inadequate seals, especially with respect to detergents.
• the older European application no. No. 061 17092.4 teaches polyelectrolyte-modified microcapsules with average particle sizes of 4.7 ⁇ m and larger, which show improved chemical cleaning resistance in the textile sector.
• microcapsules have been found, a process for their preparation and their use in textiles, binders and heat transfer fluids. Furthermore, microcapsules were found as an intermediate, a process for their preparation and their use.
• the microcapsules according to the invention comprise a capsule core and a capsule wall.
• the capsule core consists predominantly, to more than 95 wt .-%, of lipophilic substance.
• the average particle size of the capsules (Z means by means of light scattering) is 1.5 to 2.5 ⁇ m, preferably 1.7 to 2.4 ⁇ m.
• 90% of the particles have a particle size (diameter) ⁇ 4 ⁇ m, preferably ⁇ 3.5 ⁇ m, in particular ⁇ 3 ⁇ m.
• the average half-width of the microcapsule distribution is 0.2 to 1.5 ⁇ m, preferably 0.4 to 1 ⁇ m.
• the weight ratio of capsule core to capsule wall is generally from 50:50 to 95: 5.
• Preferred is a core / wall ratio of 70:30 to 93: 7.
• polyelectrolytes are arranged on the outer surface of the capsule wall.
• it is a point arrangement of the polyelectrolyte to Polyelektrolyt Schemee on the surface up to a uniform arrangement of the polyelectrolyte, which resembles a layer or shell.
• the proportion of the polyelectrolyte is 0.1 to 10 wt .-% based on the total weight of the polyelectrolyte-carrying microcapsules.
• the proportion of polyelectrolyte is preferably 0.5-5% by weight, in particular 1-3% by weight, based on the total weight of the polyelectrolyte-carrying microcapsules.
• the amount of polyelectrolyte preferred according to one embodiment is from 10 to 30% by weight, based on the total amount of monomers of the wall material.
• the preferred amount of polyelectrolyte is 5 to 15% by weight, based on the total amount of monomers of the wall material.
• Polyelectrolytes generally refer to polymers having ionizable or ionically dissociable groups which may be constituents or substituents of the polymer chain. Usually, the number of these ionizable or ionically dissociable groups in the polyelectrolyte is so great that the polymers in the ionic form (also called polyions) are water-soluble or swellable in water. Po are preferably lyelektrolyte, which have a solubility of> 4 g / l in water at 25 0 C, par- polyelectrolytes with unlimited solubility in water. Preferred are polyelectrolytes which carry an electrolyte functionality at each repeat unit.
• polyelectrolytes In contrast to protective colloids, polyelectrolytes generally have little or no emulsifying action and often have a thickening effect.
• polyelectrolytes In the context of the present invention, polyelectrolytes have an average molecular weight of 500 to 10 000 000 g / mol, preferably 1000 to 100 000 g / mol, in particular 1 000 to 10 000 g / mol. It can be used linear or branched polyelectrolytes.
• polyelectrolytes in the context of the present invention are polymers having ionizable or ionically dissociable groups with the microcapsules after polymerization - in aqueous medium, preferably water, are brought into contact.
• aqueous medium are meant aqueous mixtures containing up to 10 wt .-% based on the aqueous medium, a water-miscible solvent which is miscible in the desired amount at 25 ° C and 1 bar with water.
• alcohols such as methanol, ethanol, propanol, isopropanol, glycol, glycerol and methoxyethanol and water-soluble ethers such as tetrahydrofuran and dioxane and aprotic additives such as dimethylformamide or dimethylsulfoxide.
• cationic and anionic polyelectrolytes also referred to as polyions.
• charge of the polyion without counterion.
• Cationic polyelectrolytes arise from basic group-containing polymers (polybases) by addition of protons or quaternization.
• Anionic polyelectrolytes are formed from polymers containing acidic groups (polyacids) by elimination of protons.
• the assignment of the polyelectrolyte is carried out according to the resulting total charge of the polyion (ie without counterion). If the polyelectrolyte has predominantly positively charged, dissociated groups, then it is a cationic polyelectrolyte. On the other hand, if it has predominantly negatively charged groups, then it is an anionic polyelectrolyte. One or more cationic or one or more anionic polyelectrolytes are preferably used. Particular preference is given to choosing one or more cationic polyelectrolytes.
• a polyelectrolyte amount of at least 1% by weight of polyelectrolyte, based on the total weight of the polyelectrolyte-carrying microcapsules leads to a coating.
• a polyelectrolyte layer is applied. This layer may be one or a mixture of several like charged polyelectrolytes.
• Anionic polyelectrolytes are obtainable, for example, by free-radical polymerization of ethylenically unsaturated anionic monomers in an aqueous medium.
• ethylenically unsaturated anionic monomers are mono- ethylenically unsaturated C3- to C5-carboxylic acids such as acrylic acid, methacrylic acid, ethacrylic acid, crotonic acid, maleic acid, fumaric acid and itaconic acid, sulfonic acids such as vinylsulfonic acid, styrenesulfonic acid and acrylamidomethylpropanesulfonic acid and phosphonic acids such as vinylphosphonic acid, and / or in each case the alkali metal, alkaline earth metal and / or ammonium salts of these acids into consideration.
• Preferred anionic monomers include acrylic acid, methacrylic acid, maleic acid and acrylamido-2-methylpropanesulfonic acid. Particularly preferred are aqueous dispersions of polymers based on acrylic acid.
• the anionic monomers can be polymerized either alone to form homopolymers or else mixed with one another to give copolymers. Examples include the homopolymers of acrylic acid, homopolymers of methacrylic acid or copolymers of acrylic acid and maleic acid, copolymers of acrylic acid and methacrylic acid and copolymers of methacrylic acid and maleic acid.
• the polymerization of the anionic monomers can also be carried out in the presence of at least one other ethylenically unsaturated monomer.
• These monomers may be nonionic or may carry a cationic charge.
• nonionic comonomers examples include acrylamide, methacrylamide, N-Cr to C3-alkylacrylamides, N-vinylformamide, acrylic esters of monohydric alcohols having from 1 to 20 carbon atoms, in particular methyl acrylate, ethyl acrylate, isobutyl acrylate and n- Butyl acrylate, methacrylic acid esters of monohydric alcohols having 1 to 20 carbon atoms z. For example, methyl methacrylate and ethyl methacrylate, and vinyl acetate and vinyl propionate.
• Suitable cationic monomers which can be copolymerized with the anionic monomers are dialkylaminoethyl acrylates, dialkylaminoethyl methacrylates, dialkylaminopropyl acrylates, dialkylaminopropyl methacrylates, dialkylaminoethylacrylamides, dialkylaminoethylmethacrylamides, dialkylaminopropylacrylamides, dialkylaminopropylmethacrylamides, diallyldimethylammonium chloride, vinylimidazole and the cationic monomers neutralized and / or quaternized with mineral acids , Specific examples of cationic monomers are dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, diethylaminoethyl methacrylate, dimethyaminopropyl acrylate, dimethylaminopropyl
• the cationic monomers may be completely or even partially neutralized or quaternized, for. B. in each case to 1 to 99%.
• Preferred quaternizing agent for the cationic monomers is dimethylsulfate.
• the quaternization of the monomers can also be carried out with diethyl sulfate or with alkylating agents, in particular alkyl halides such as methyl chloride, ethyl chloride or benzyl chloride.
• the comonomers are used in the preparation of the anionic polyelectrolytes, for example, in amounts such that the resulting polymer dispersions when diluted with water and at pH values above 7.0 and a temperature of 20 0 C are water-soluble and have an anionic charge.
• the amount of nonionic and / or cationic comonomers z. B. 0 to 99, preferably 5 to 75 wt .-% and is usually in the range of 5 to 25 wt .-%.
• the cationic monomers are used at most in an amount such that the entste- Henden polyelectrolytes ⁇ 6.0 and a temperature of 20 0 C carry a total anionic charge at pH values.
• the anionic excess charge in the resulting amphoteric polymers is z. B. at least 5 mol%, preferably at least 10 mol%, in particular at least 30 mol%, very particularly preferably at least 50 mol%.
• Examples of preferred copolymers are copolymers of 25 to 90% by weight of acrylic acid and 75 to 10% by weight of acrylamide.
• Particular preference is given to homopolymers of acrylic acid obtainable by free-radical polymerization of acrylic acid in the absence of other monomers.
• crosslinkers for the preparation of branched polyelectrolytes it is possible to use all compounds which have at least two ethylenically unsaturated double bonds in the molecule. Such compounds are used, for example, in the preparation of crosslinked polyacrylic acids such as superabsorbent polymers, cf. EP-A 0 858 478, page 4, line 30 to page 5, line 43.
• crosslinkers are triallylamine, pentaerythritol triallether, pentaerythritol tetraallyl ether, methylenebisacrylamide, N, N'-divinylethyleneurea, at least two allyl-containing allyl ethers or at least two vinyl-containing vinyl ethers of polyhydric alcohols such.
• sorbitol 1, 2-ethanediol, 1, 4-butanediol, trimethylolpropane, glycerol, diethylene glycol and of sugars such as sucrose, glucose, mannose, completely with acrylic acid or methacrylic acid esterified dihydric alcohols having 2 to 4 carbon atoms such as ethylene glycol dimethacrylate , Ethylene glycol diacrylate, butanediol dimethacrylate, butanediol diacrylate, diacrylates or dimethacrylates of polyethylene glycols having molecular weights of 300 to 600, ethoxylated trimethylenepropane triacrylates or ethoxylated trimethylene propane trimethacrylates, 2,2-bis (hydroxymethyl) butanol trimethacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate and triallylmethylammonium chloride.
• sugars such as sucrose, glucose, man
• crosslinking agents are used in the preparation of the dispersions according to the invention, the amounts of crosslinker used in each case are, for example, 0.0005 to 5.0, preferably 0.001 to 1.0,% by weight, based on the total monomers used in the polymerization.
• Preferred crosslinkers are pentaerythritol triallyl ether, pentaerythritol tetraallyl ether, N, N'-divinylethyleneurea, at least two allyl groups-containing allyl ethers of sugars such as sucrose, glucose or mannose, and triallylamine and mixtures of these compounds.
• polycondensates for example phenolsulfonic acid resins.
• aldehyde condensates especially based on formaldehyde, acetaldehyde, isobutyraldehyde, propionaldehyde, glutaraldehyde and glyoxal, especially formaldehyde condensates based on phenolsulfonic acids.
• Amines or amides in particular those of carbonic acid such as urea, melamine or dicyandiamide for the production of Phenolsulfonklaze be used.
• the phenolsulfonic acid resins are preferably present as salts.
• the condensation products of the invention preferably have a degree of condensation of from 1 to 20 and an average molecular weight of from 500 to 10,000 g / mol.
• the phenolsulfonic acid resins are preferably prepared analogously to the manner specified in EP-A 816 406.
• cationic polyelectrolytes are polymers from the group of
• Such polymers are known and commercially available.
• the monomers underlying the cationic polyelectrolytes of groups a-f can be used in the form of the free base, but preferably in the form of their salts with mineral acids such as hydrochloric acid, sulfuric acid or phosphoric acid and in quaternized form for the polymerization.
• Suitable quaternizing agents are, for example, dimethyl sulfate, diethyl sulfate, methyl chloride, ethyl chloride, cetyl chloride or benzyl chloride.
• polydiallyldimethylammonium chlorides (b) polydiallyldimethylammonium chlorides, (c) polyvinylamines and partially hydrolyzed polyvinylformamides, (d) polyethylenimines (e) polydimethylaminoethyl acrylate, polydimethylaminoethyl methacrylate, copolymers of acrylamide and dimethylaminoethyl acrylate and copolymers of acrylamide and dimethylaminoethyl methacrylate, where the basic monomers may also be present in the form of the salts with mineral acids or in quaternized form, and
• the average molecular weights M w of the cationic polyelectrolytes are at least 500 g / mol. They are, for example, in the range of 500 g / mol to 10 million g / mol, preferably in the range of 1,000 to 500,000 g / mol and most often 1,000 to 5,000 g / mol.
• polyvinylamines and partially hydrolyzed polyvinylformamides having an average molecular weight Mw of 500 to 10,000 g / mol
• polyethyleneimines having an average molecular weight Mw of 500 to 10,000 g / mol.
• the copolymers of vinylimidazolium methosulfate and N-vinylpyrrolidone listed under (a) contain, for example, 10 to 90% by weight of N-vinylpyrrolidone polymerized.
• N-vinylpyrrolidone can be used as comonomer at least one compound from the group of ethylenically unsaturated C3 to Cs carboxylic acids such as acrylic acid or methacrylic acid or esters of these carboxylic acids with 1 to 18 carbon atoms containing monohydric alcohols such as methyl acrylate, ethyl acrylate , Isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, methyl methacrylate, ethyl methacrylate or n-butyl methacrylate.
• Polymers of group (b) are preferably polydiallyldimethylammonium chloride. Also suitable are copolymers of diallyldimethylammonium chloride and dimethylaminoethyl acrylate, copolymers of diallyldimethylammonium chloride and dimethylaminoethyl methacrylate, copolymers of diallyldimethylammonium chloride and diethylaminoethyl acrylate, copolymers of diallyldimethylammonium chloride and dimethylaminopropyl acrylate, copolymers of diallyldimethylammonium chloride and dimethylaminoethylacrylamide and copolymers of diallyldimethylammonium chloride and dimethylaminopropylacrylamide.
• the Copoylmeri- sate of diallyldimethylammonium chloride contain, for example, 1 to 50, usually 2 to 30 mol% of at least one of said comon
• Vinylamine-containing polymers (c) are obtainable by polymerizing N-vinylformamide optionally in the presence of comonomers and hydrolysis of the polyvinylformamides with elimination of formyl groups to form amino groups.
• the degree of hydrolysis of the polymers may be, for example, 1 to 100% and is preferably in the range of 60 to 100%.
• partially hydrolyzed polyvinylformamides mean a degree of hydrolysis of> 50%, preferably of> 90%.
• the preparation of homopolymers and copolymers of N-vinylformamide and the hydrolysis of these polymers to form polymers containing vinylamine units are described in detail, for example, in US Pat. No. 6,132,558, column 2, line 36 to column 5, line 25. The statements made there are hereby incorporated by reference into the disclosure of the present invention.
• Vinylamine-containing polymers are sold, for example as Catiofast® ® and Polymin® ® trademarks of BASF Aktiengesellschaft.
• Ethylenimine units containing polymers of group (d) such as polyethyleneimines are also commercial products. They are, for example, under the name Polymin® ® from BASF Aktiengesellschaft sold eg Polymin® ® SK. These cationic polymers are polymers of ethyleneimine obtained by polymerizing ethyleneimine in an aqueous medium in the presence of small amounts of acids or acid-forming compounds such as halogenated hydrocarbons, e.g. As chloroform, carbon tetrachloride, tetrachloroethane or ethyl chloride or condensation products of epichlorohydrin and amino-containing compounds such as mono- and polyamines z.
• halogenated hydrocarbons e.g. As chloroform, carbon tetrachloride, tetrachloroethane or ethyl chloride or condensation products of epichlorohydrin and amino-containing compounds such as mono- and polyamines z.
• dimethylamine diethylamine, ethylenediamine, diethylenetriamine and triethylenetetramine or ammonia. They have for example molar masses M w of 500 to 1 million, preferably 1000 to 500 000 g / mol.
• cationic polymers also include graft polymers of ethyleneimine on compounds having a primary or secondary amino group, for.
• Suitable cationic polymers of group (e) are polymers containing dialkylaminoalkyl acrylate and / or dialkylaminoalkyl methacrylate units. These monomers may be used in the form of the free bases, but preferably in the form of the salts with mineral acids such as hydrochloric acid, sulfuric acid or phosphoric acid and in quaternized form in the polymerization. Suitable quaternizing agents are, for example, dimethyl sulfate, diethyl sulfate, methyl chloride, ethyl chloride, cetyl chloride or benzyl chloride. Both homopolymers and copolymers can be prepared from these monomers.
• Suitable comonomers are, for example, acrylamide, methacrylamide, N-vinylformamide, N-vinylpyrrolidone, methyl acrylate, ethyl acrylate, methyl methacrylate and mixtures of the monomers mentioned.
• Cationic polymers of group (f) are polymers containing dimethylaminoethylacrylamide or dimethylaminoethylmethacrylamide units and containing the cationic monomers preferably in the form of salts with mineral acids or in quaternized form. These may be homopolymers and copolymers.
• Examples are homopolymers of dimethylaminoethylacrylamide which is completely quaternized with dimethyl sulfate or with benzyl chloride, homopolymers of dimethylaminoethylmethacrylamide which is completely quaternized with dimethylsulphate, methyl chloride, ethyl chloride or benzyl chloride, and copolymers of acrylamide and dimethylaminoethylacrylamide quaternized with dimethylsulphate.
• amphoteric polymers can also be used as cationic polymers, provided that they carry a total cationic charge.
• the cationic excess charge in the amphoteric polymers is for example at least 5 mol%, preferably at least 10 mol%, and is usually in the range from 15 to 95 mol%.
• amphoteric polymers with a cationic excess charge are Copolymers of acrylamide, dimethylaminoethyl acrylate and acrylic acid containing at least 5 mol% more dimethylaminoethyl acrylate copolymerized than acrylic acid, - copolymers of vinylimidazolium methosulfate, N-vinylpyrrolidone and acrylic acid containing polymerized at least 5 mol% more Vinylimidazoliummethosulfat than acrylic acid, hydrolyzed from copolymers N-vinylformamide and an ethylenically unsaturated C3 to C ⁇ carboxylic acid, preferably acrylic acid or methacrylic acid, with a content of vinylamine units which is at least 5 mol% higher than
• Polyelectrolytes which are suitable according to the invention can also be biopolymers, such as alginic acid, gum arabic, nucleic acids, pectins, proteins, and chemically modified biopolymers, such as ionic or ionizable polysaccharides, eg. As carboxymethyl cellulose, chitosan, chitosan sulfate, and lignin sulfonate.
• biopolymers such as alginic acid, gum arabic, nucleic acids, pectins, proteins
• chemically modified biopolymers such as ionic or ionizable polysaccharides, eg. As carboxymethyl cellulose, chitosan, chitosan sulfate, and lignin sulfonate.
• the polyelectrolyte is preferably selected from the group comprising polyacrylic acids, phenolsulfonic acid precondensates, polydiallyldimethylammonium chlorides, polyvinylamines, partially hydrolyzed polyvinylformamides and polyethyleneimine.
• anionic polyelectrolytes are preferred, in particular the polyacrylic acids and phenolsulfonic acid resins.
• cationic polyelectrolytes are preferred, in particular groups (b), (c) and (d), ie polydiallyldimethylammonium chlorides, polyvinylamines and partially hydrolyzed polyvinylformamides and polyethyleneimines.
• Polydiallyldimethylammonium chlorides are particularly preferably used as cationic polyelectrolytes.
• microcapsules according to the invention are obtained by constructing microcapsules comprising a capsule core and a capsule wall
• microcapsules each based on the total weight of the monomers, wherein the microcapsules have an average particle size of 1, 5 - 2.5 microns and 90% of the particles have a particle size ⁇ 4 microns, in contact with one or more polyelectrolytes in water or an aqueous medium , Preferably, a microcapsule dispersion is contacted with one or more polyelectrolytes.
• they are obtained by a) preparing an oil-in-water emulsion containing the monomers, the lipophilic substance and polyvinyl alcohol and / or partially hydrolyzed polyvinyl acetate, the average size of the oil droplets being 1.5- 2.5 ⁇ m, b) the monomers of the oil-in-water emulsion obtained in a) are radically polymerized and the microcapsules optionally isolated c) the microcapsules or microcapsule dispersion obtained according to b) with one or more polyelectrolytes, if appropriate in water or an aqueous medium Contact brings.
• the microcapsules according to the invention can subsequently be isolated by spray drying.
• the process step of radical polymerization b) produces an initial microcapsule dispersion as an intermediate, which is brought into contact with the polyelectrolyte in step c).
• the particle size distribution of the polyelectrolyte-modified microcapsule dispersion is unchanged from the initial microcapsule dispersion.
• Microcapsule dispersion brought into contact with one or more polyelectrolytes so without intermediate isolation of the microcapsules. Since in this case an aqueous dispersion is present, one already has the desired medium in which the microcapsules and the polyelectrolyte can be brought into contact. By bringing into contact is meant, for example, mixing with conventional stirrers or mixers.
• the polyelectrolyte is added to the starting microcapsule dispersion in bulk or in solution, preferably as an aqueous solution.
• the amount of polyelectrolyte is 0.1 to 5 wt .-%, preferably 0.25 to 1, 5 wt .-% based on the réellemik- rokapselmenge.
• the capsule wall of the microcapsules is composed of 10 to 100 wt .-%, preferably 30 to 99 wt .-% of one or more Ci-C24-alkyl esters of acrylic and / or methacrylic acid as monomers I.
• the polymers may contain up to 80% by weight, preferably from 1 to 70% by weight, particularly preferably from 5 to 60% by weight, in particular from 10 to 50% by weight, of a bi- or polyfunctional monomer as monomers II, which is insoluble or sparingly soluble in water, in copolymerized form.
• the polymers may contain up to 90% by weight, preferably 0.5 to 50% by weight, in particular 1 to 30% by weight, of other monomers III in copolymerized form.
• Suitable monomers I are C 1 -C 24 -alkyl esters of acrylic and / or methacrylic acid. Particularly preferred monomers I are methyl, ethyl, n-propyl and n-butyl acrylate and / or the corresponding methacrylates. Iso-propyl, isobutyl, sec-butyl and tert-butyl acrylate and the corresponding methacrylates are preferred. Further, methacrylonitrile is mentioned. Generally, the methacrylates are preferred.
• Suitable monomers II are bi- or polyfunctional monomers which are insoluble or sparingly soluble in water but have good to limited solubility in the lipophilic substance. Low solubility is to be understood as meaning a solubility of less than 60 g / l at 20 ° C.
• bi- or polyfunctional monomers is meant compounds having at least 2 non-conjugated ethylenic double bonds.
• divinyl and polyvinyl monomers come into consideration, which cause cross-linking of the capsule wall during the polymerization.
• Preferred bifunctional monomers are the diesters of diols with acrylic acid or methacrylic acid, furthermore the diallyl and divinyl ethers of these diols.
• Particular preference is given to propanediol, butanediol, pentanediol and hexanediol diacrylate or the corresponding methacrylates.
• Preferred polyvinyl monomers are trimethylolpropane triacrylate and methacrylate, pentaerythritol triallyl ether and pentaerythritol tetraacrylate.
• Suitable monomers III are other monomers III which are different from the monomers I and II, such as vinyl acetate, vinyl propionate, vinylpyridine and styrene. Particular preference is given to charge-bearing or ionizable group-carrying monomers IIIa which are different from the monomers I and II, such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, maleic anhydride, 2-hydroxyethyl acrylate and methacrylate, acrylamido-2-methylpropanesulfonic acid, acrylonitrile, Methacrylamide, N-vinylpyrrolidone, N-methylolacrylamide, N-methylolmethacrylamide, dimethylaminoethyl methacrylate and diethylaminoethyl methacrylate.
• charge-bearing or ionizable group-carrying monomers IIIa which are different from the monomers I and II, such as acrylic acid, methacrylic acid, itac
• Ci-C24-alkyl esters of acrylic and / or methacrylic acid as monomers I 1 to 70 wt .-%, preferably 5 to 60 wt .-%, in particular 10 to 50 wt. %, of a bi- or polyfunctional monomer as monomers II, which is insoluble or sparingly soluble in water,
• the wall-forming polymers of 30 to 90 wt .-% methacrylic acid, 10 to 70 wt .-% of an alkyl ester of (meth) acrylic acid, preferably methyl methacrylate, tert-butyl methacrylate, Phenylmethacrylat and cyclohexyl methacrylate, and 0 to 40 wt .-% further ethylenically unsaturated monomers formed.
• These further ethylenically unsaturated monomers may be the monomers I, II and / or III not previously mentioned for this embodiment.
• microcapsules according to the invention can be prepared by a so-called in situ polymerization.
• the principle of microcapsule formation is based on preparing a stable oil-in-water emulsion from the monomers, a radical initiator, a protective colloid and the lipophilic substance to be encapsulated. Subsequently, the polymerization of the monomers is initiated by heating and optionally controlled by further increase in temperature, the resulting polymers forming the capsule wall which encloses the lipophilic substance.
• This general principle is described, for example, in DE-A-10 139 171, the content of which is expressly incorporated by reference.
• an oil-in-water emulsion is prepared containing the monomers, the lipophilic substance and polyvinyl alcohol and / or partially hydrolyzed polyvinyl acetate, the average size of the oil droplets being 1.5- 2.5 ⁇ m (step a).
• the size of the oil droplets corresponds almost to the size of the microcapsules present after the polymerization.
• polyvinyl alcohol and / or partially hydrolyzed polyvinyl acetate as protective colloids leads to the microcapsule distributions according to the invention.
• polyvinyl alcohol or partially hydrolyzed polyvinyl acetate are used in a total amount of at least 3% by weight, preferably from 6 to 8% by weight, based on the microcapsules (without protective colloid).
• protective colloids as mentioned in WO 2005/1 16559 in addition to the amounts of polyvinyl alcohol or partially hydrolyzed polyvinyl acetate which are preferred according to the invention.
• microcapsules according to the invention are preferably prepared only with polyvinyl alcohol and / or partially hydrolyzed polyvinyl acetate and without the addition of further protective colloids.
• Polyvinyl alcohol is obtainable by polymerizing vinyl acetate, optionally in the presence of comonomers, and hydrolysing the polyvinyl acetate with cleavage the acetyl groups to form hydroxyl groups.
• the degree of hydrolysis of the polymers may be, for example, 1 to 100%, and is preferably in the range of 50 to 100%, more preferably 65 to 95%.
• partially hydrolyzed polyvinyl acetates are to be understood as meaning a degree of hydrolysis of ⁇ 50% and polyvinyl alcohol of> 50 to 100%.
• the preparation of homo- and copolymers of vinyl acetate and the hydrolysis of these polymers to form polymers containing vinyl alcohol units are well known.
• Vinyl alcohol units-containing polymers are sold, for example as Mowiol ® brands from Kuraray Specialties Europe (KSE).
• Preferred are polyvinyl alcohols or partially hydrolyzed polyvinyl acetates, deren- viscosity of a 4 wt .-% aqueous solution at 20 0 C in accordance with DIN 53015 has a value in the range from 3 to 56 mPa * s, preferably a value of 14 to 45 mPa * s, in particular from 22 to 41 mPa * s.
• polyvinyl alcohol or partially hydrolyzed polyvinyl acetate leads to a stable emulsion.
• This allows the polymerization, ie the wall formation to be carried out only with stirring, which only applies to better temperature compensation.
• the dispersing conditions for preparing the stable oil-in-water emulsion are preferably chosen as described in DE-A-10230581. In general, it is necessary to disperse until the oil droplets have the size of the desired microcapsules, since at most insignificant changes in size occur during the wall-forming process.
• the usual peroxo and azo compounds advantageously in amounts of 0.2 to 5 wt .-%, based on the weight of the monomers used.
• radical initiator Depending on the state of aggregation of the radical initiator and its solubility behavior, it can be fed as such, but preferably as a solution, emulsion or suspension, as a result of which, in particular, small amounts of radical initiator can be metered more precisely.
• Preferred free-radical initiators are tert-butyl peroxoneodecanoate, tertiary
• radical initiators are di (3,5,5-trimethylhexanoyl) peroxide, 4,4'-azobisisobutyronitrile, tert-butyl perpivalate and dimethyl 2,2-azobisisobutyrate. These have a half-life of 10 hours in a temperature range of 30 to 100 0 C.
• the polymerization is carried out at 20 to 100 0 C, preferably at 40 to 95 ° C.
• the oil-in-water emulsion is to be formed at a temperature at which the core material is liquid / oily. Accordingly, a radical initiator must be selected whose decomposition temperature above this temperature and the polymerization are also carried out 2 to 50 0 C above this temperature, so that optionally selects radical initiator whose decomposition temperature is above the melting point of the lipophilic substance.
• a common process variant for lipophilic substances with a melting point up to about 60 ° C is a reaction temperature starting at 60 ° C, which is increased in the course of the reaction to 85 ° C.
• Advantageous free radical initiators have a 10-hour half life in the range of 45 to 65 ° C, such as t-butyl perpivalate.
• a temperature program which starts at correspondingly higher reaction temperatures.
• Radical initiators are preferred with a 10-hour half-life in the range of 70 to 90 0 C, such as t-butyl per-2-ethylhexanoate for initial temperatures of around 85 ° C.
• the polymerization is carried out at atmospheric pressure, but it is also possible at reduced or slightly elevated pressure z.
• the reaction times of the polymerization are normally 1 to 10 hours, usually 2 to 5 hours.
• the inventive method using polyvinyl alcohol and / or partially hydrolyzed polyvinyl acetate allows a simplified procedure. So it is not necessary - but possible - to disperse at room temperature, but it can be dispersed and polymerized directly at elevated temperature, so that can be dispensed with the otherwise usual controlled first heating phase after the dispersion.
• aqueous microcapsule dispersions substantially free of odor carriers, such as residual monomers and other volatile organic constituents.
• This can be achieved physically in a manner known per se by distillative removal (in particular via steam distillation) or by stripping with an inert gas.
• distillative removal in particular via steam distillation
• stripping with an inert gas.
• it can be done chemically, as described in WO 99/24525, advantageously by redox-initiated polymerization, as described in DE-A 44 35 423, DE-A 44 19 518 and DE-A 44 35 422.
• the microcapsules according to the invention are suitable for copying paper, in cosmetics, for the encapsulation of fragrances, flavorings or adhesives, or in crop protection.
• the microcapsules according to the invention are particularly suitable for latent heat storage materials.
• latent heat storage materials are substances which have a phase transition in the temperature range in which heat transfer is to be carried out.
• the lipophilic substance preferably has a solid / liquid phase transition in the temperature range from -20 to 120 ° C.
• Suitable substances may be mentioned by way of example:
• aliphatic hydrocarbon compounds such as saturated or unsaturated C 10 -C 40 -hydrocarbons, which are branched or preferably linear, such as n-tetradecane, n-pentadecane, n-hexadecane, n-heptadecane, n-octadecane, n-nonadecane, n-eicosane, n- Heneicosane, n-docosane, n-tricosane, n-tetracosane, n-pentacosane, n-hexacosane, n-heptacosane, n-octacosane and cyclic hydrocarbons, eg cyclohexane, cyclooctane, cyclodecane; aromatic hydrocarbon compounds such as benzene, naphthalene, biphenyl, o- or
• decylnaphthalene saturated or unsaturated C ⁇ -Cso fatty acids such as lauric, stearic, oleic or behenic acid, preferably eutectic mixtures of decanoic acid with e.g.
• Myristic, palmitic or lauric acid Fatty alcohols such as lauryl, stearyl, oleyl, myristyl, cetyl alcohol, mixtures such as coconut fatty alcohol and the so-called oxo alcohols, which are obtained by hydroformylation of ⁇ -olefins and further reactions; C 6 -C 30 fatty amines, such as decylamine, dodecylamine, tetradecylamine or hexadecylamine; Esters, such as C 1 -C 10 -alkyl esters of fatty acids, such as propyl palmitate, methyl stearate or ethylphenyl, and preferably their eutectic mixtures or methyl cinnamate; natural and synthetic waxes such as montan acid waxes, montan ester waxes, carnauba wax, polyethylene wax, oxidized waxes, polyvinyl ether wax, ethylene vinyl acetate wax or Fischer
• halogenated hydrocarbons such as chlorinated paraffin, bromoctadecane, bromopentadecane, bromononadecane, bromeicosane, bromodocosan.
• mixtures of these substances are suitable, as long as it does not come to a melting point lowering outside the desired range, or the heat of fusion of the mixture is too low for a meaningful application.
• n-alkanes for example, it is advantageous to use pure n-alkanes, n-alkanes having a purity of greater than 80%, or alkane mixtures, such as are obtained as a technical distillate and are commercially available as such.
• soluble compounds may be added to the lipophilic substances so as to prevent the freezing point depression which sometimes occurs with the nonpolar substances. It is advantageous to use, as described in US Pat. No. 5,456,852, compounds having a melting point 20 to 120 K higher. point as the actual core substance. Suitable compounds are the fatty acids mentioned above as lipophilic substances, fatty alcohols, fatty amides and aliphatic hydrocarbon compounds. They are added in amounts of from 0.1 to 10% by weight, based on the capsule core.
• the latent heat storage materials are selected. For example, it is preferred for heat storage in building materials in a moderate climate latent heat storage materials whose solid / liquid phase transition in the temperature range of 0 to 60 0 C. Thus, one usually chooses for indoor applications, or mixtures with conversion temperatures of 15 to 30 0 C. In solar applications as a storage medium or to avoid overheating of transparent thermal insulation, as described in EP-A-333 145, are mainly conversion temperatures of 30-60 ° C suitable. For applications in the textile sector, especially transition temperatures of 0 to 40 0 C advantageous for heat transfer fluids from -10 to 120 0 C.
• Preferred latent heat storage materials are aliphatic hydrocarbons, particularly preferably those listed above by way of example.
• aliphatic hydrocarbons having 14 to 20 carbon atoms and mixtures thereof are preferred.
• the present invention further relates to microcapsules comprising a capsule core and a capsule wall constructed from
• microcapsules have an average particle size of 1, 5 - 2.5 microns and 90% of the particles have a particle size ⁇ 4 microns, preferably ⁇ 3.5 microns, in particular ⁇ 3 microns have as an intermediate.
• the half-width of the microcapsule distribution is 0.2 to 1.5 ⁇ m, preferably 0.4 to 1 ⁇ m.
• the intermediate is obtained according to the method described above.
• the aqueous dispersions of the microcapsules obtained according to the invention allow a reaction without further intermediate isolation. tion of the microcapsules to the electrolyte-carrying microcapsules according to the invention. In addition, it also has advantageous properties even in some applications of microencapsulated latent heat storage materials.
• microcapsule powder according to the invention is diverse. Thus, it is advantageous to use for modifying fibers and fabrics, for example, textile fabrics and nonwovens (e.g., nonwovens), etc.
• microcapsule coatings, foams with microcapsules and microcapsule-modified textile fibers may be mentioned as application forms.
• the microcapsules are applied to a fabric together with a polymeric binder and optionally other excipients, usually as a dispersion.
• Typical textile binders are film-forming polymers having a glass transition temperature in the range from -45 to 45 ° C, preferably -30 to 12 ° C.
• microcapsule coatings are described, for example, in WO 95/34609, to which reference is expressly made.
• the modification of foams with microcapsules is carried out in a similar manner as described in DE 981576T and US 5,955,188.
• the prefoamed substrate preferably a polyurethane or polyether, is surface-treated with a binder-containing microcapsule dispersion.
• the binder-microcapsule mixture passes by applying a vacuum in the open-pore foam structure in which the binder hardens and binds the microcapsules to the substrate.
• Another processing option is the modification of the textile fibers themselves, e.g.
• the microcapsule powder according to the invention has a good chemical cleaning resistance.
• binders with mineral, silicate or polymeric binders are characterized by their resistance to hydrolysis against the aqueous and often alkaline aqueous materials.
• a mineral shaped body is understood to be a shaped body which is formed from a mixture of a mineral binder, water, additives and, if appropriate, auxiliaries after shaping by hardening the mineral binder / water mixture as a function of time, optionally under the effect of elevated temperature.
• Mineral binders are well known.
• inorganic substances such as lime, gypsum, clay, loam and / or cement, which are transferred by mixing with water in their ready-to-use form, the latter being left to itself, in the air or under water, optionally under the action elevated temperature, as a function of time stone-like solidify.
• the aggregates are usually made of granular or fibrous natural or artificial rock (gravel, sand, glass or mineral fibers), in special cases also of metals or organic aggregates or mixtures of said aggregates, with grain sizes or fiber lengths, the respective purpose in are adapted in a known manner. Frequently, for the purpose of coloring and colored pigments are also used as surcharges.
• Suitable auxiliaries are, in particular, those substances which accelerate or retard the hardening or which influence the elasticity or porosity of the solidified mineral shaped body. These are in particular polymers, as z. For example, from US-A 4,340,510, GB-PS 1 505 558, US-A 3,196,122, US-A 3,043,790, US-A 3,239,479, DE-A 43 17 035, DE-A 43 17 036 , JP-A 91/131 533 and other writings are known.
• the polyelectrolyte-modified microcapsules according to the invention and their unmodified intermediate are suitable for modifying mineral binders (mortar-like preparations) containing a mineral binder consisting of 70 to 100% by weight of cement and 0 to 30% by weight of gypsum. This is especially true when cement is the sole mineral binder.
• the effect according to the invention is essentially independent of the type of cement. Depending on the project so blast furnace cement, oil shale cement, Portland cement, hydrophobic Portland cement, quick-setting cement, swelling cement or alumina cement can be used, with the use of Portland cement proves to be particularly favorable. For further details, reference is made to DE-A 196 23 413.
• the dry compositions of mineral binders contain 0.1 to 20 wt .-% microcapsules.
• the polyelectrolyte-modified microcapsules according to the invention and their unmodified intermediate are preferably used as additives in mineral coating compositions such as plaster.
• Such a plaster for the interior is usually composed of gypsum as a binder.
• the weight ratio of gypsum / microcapsule is from 95: 5 to 70: 30. Higher microcapsule proportions are, of course, possible.
• Exterior coatings such as exterior facades or damp rooms may contain cement (cementitious plasters), lime or waterglass (mineral or silicate plasters) or plastic dispersions (synthetic resin plasters) as binders together with fillers and optionally coloring pigments.
• cement cementitious plasters
• lime or waterglass mineral or silicate plasters
• plastic dispersions synthetic resin plasters
• the proportion of microcapsules in the total solids corresponds to the weight ratios for gypsum plasters.
• polyelectrolyte-modified microcapsules according to the invention and their unmodified intermediate are suitable as additives in polymeric moldings or polymeric coating compositions.
• thermoplastic and thermosetting plastics to understand in their processing, the microcapsules are not destroyed.
• examples are epoxy, urea, melamine, polyurethane and silicone resins and also paints both solvent-based, high-solids-based, powder coating or water-based paint and dispersion films.
• the microcapsule powder is also suitable for incorporation in plastic foams and fibers.
• foams are polyurethane foam, polystyrene foam, latex foam and melamine resin foam.
• polyelectrolyte-modified microcapsules according to the invention and their unmodified intermediate are suitable as additives in lignocellulose-containing moldings, such as chipboard.
• the polyelectrolyte-modified microcapsules according to the invention and their unmodified intermediate are suitable for modifying plasterboard.
• the production of plasterboard with microencapsulated latent heat storage is well known and described in EP-A 1 421 243 which is incorporated herein by reference.
• Alternative fibrous structures may also be used as double-sided covers for the "gypsum board” instead of cellulose-based board
• Alternative materials include polymer fibers made from, for example, polypropylene, polyester, polyamide, polyacrylates, polyacrylonitrile and the like The alternative materials can be used as fabric and as so-called “nonwovens", ie as fleece-like structures.
• Such structural panels are known for example from US 4,810,569, US 4,195,110 and US 4,394,411.
• thermoelectric-modified microcapsules according to the invention and their unmodified intermediate are suitable for the production of heat transfer fluid.
• heat transfer fluid in the context of this application, both liquids for the transport of heat as well as liquids for the transport of cold, ie cooling liquids meant.
• the principle of heat energy transfer is the same in both cases and differs only in the direction of transfer.
• the particle size of the microcapsule powder was determined with a Malvern Particle Sizer Type 3600E according to a standard measuring method documented in the literature.
• the half-width is the width of the distribution halfway up the maximum.
• the D (0, 9) value indicates that 90% of the particles have a particle size (by volume) less than or equal to this value.
• the D (0, 1) value indicates that 10% of the particles have a particle size (by volume average) up to this value.
• D (0, 5) means that 50% of the particles have a particle size (by volume) less than or equal to this value.
• the span value results from the quotient of the difference (D (0, 9) - D (0, 1)) and D (0, 5).
• Example 4 (without polyelectrolyte)
• Example 4 100 g of the obtained according to Example 4 microcapsule dispersion (solids content 40% by weight) was then added with stirring with 2 g of a 20 wt .-% aqueous solution of a phenol sulfonic acid polycondensate (Tamol ® DN, BASF Aktiengesellschaft). The evaporation rate was only 3.6%, with unchanged particle size distribution in comparison to Example 4.
• Example 4 microcapsule dispersion 100 g of the obtained according to Example 4 microcapsule dispersion (solids content 40% by weight) was then with stirring with 1, 33 g of a 30% aqueous solution of a poly (N, N-diallyl-N, N-dimethylammonium chloride) based cationic polymer with a viscosity of 500 mPa * s according to ISO 2555 (Catiofast ® CS, BASF Aktiengesellschaft). The evaporation rate was only 5.8%, with unchanged in comparison to Example 4 particle size distribution.
• Example 8 (without polyelectrolyte) water phase 437 g of water
• Example 10 (without polyelectrolyte, not according to the invention)

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