Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F8/00—Chemical modification by after-treatment
  • C08F8/28—Condensation with aldehydes or ketones
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
  • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
  • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
  • C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
  • C04B35/632—Organic additives
  • C04B35/634—Polymers
  • C04B35/63404—Polymers obtained by reactions only involving carbon-to-carbon unsaturated bonds
  • C04B35/6342—Polyvinylacetals, e.g. polyvinylbutyral [PVB]

Definitions

• the invention relates to highly acetalized, coarse-grained polyvinylacetacetals, processes for their preparation and their use.
• polyvinyl acetals which are obtained from the corresponding polyvinyl alcohols by polymer-analogous reaction with the corresponding aldehydes, has been known since 1924, wherein in the subsequent period a variety of aldehydes have been used for the preparation of the corresponding polyvinyl acetals.
• Polyvinyl acetals are generally prepared in a three-stage process (polyvinyl acetate -> polyvinyl alcohol -> polyvinyl acetal), resulting in products which, in addition to vinyl acetal groups, also contain vinyl alcohol and vinyl acetate units.
• Polyvinyl formal, polyvinyl acetacetal and polyvinyl butyral (PVB) have gained commercial importance.
• Polyvinyl acetals are used for laminated safety glass and glass composites, high-security glass or pane foils. Due in part to their good pigment binding power, polyvinyl butyrals in particular are also used as binders in paints and especially in printing inks.
• the corresponding partially or completely hydrolyzed polyvinyl ester (polyvinyl alcohol) is acetalated with the corresponding aldehyde in the presence of acid.
• the acetalization reaction is initiated at low temperature I 1 and then continued at higher temperature T2 and completed.
• Comparative Example B-5 shows that at a temperature level T 2 of +50 0 C only 71.5 mol% acetalization degree could be achieved.
• an insufficient solubility in non-alcoholic solvents such as methyl ethyl ketone (MEK).
• Grain size of Polyvinyacetacetals significantly over the temperature Ti at the initiation of the acetalization is determined. Temperatures I 1 of + 19 ° C and more lead to very coarse and uneven grain.
• the examples in EP 0 271 861 A2 show no discernible dependence of the grain size on the temperature T 2 for the continuation of the reaction.
• a disadvantage of this method is therefore that the product with degrees of acetalization> 70 mol% with a relatively fine grain of 25 to 75 microns average grain size obtained and only at low degrees of acetalization of ⁇ 70 mol% average particle sizes over 100 microns can be achieved can.
• EP 1384731 Al the acetalization is recommended to initiate in a temperature range of Ti of -10 0 C to +30 0 C and the temperature T then adjusted to 50 0 C to 8O 0 C. 2 However, no degree of acetalization> 80 mol% is achieved with this method.
• EP 1284274 Al EP 1369439 Al and WO 2004/026917 Al are described in which initiated the acetalization at temperatures of I 1 in the range of -10 0 C to + 30 ° C and methods at temperatures T 2 in the range of
• EP 1 270 608 A1 a method is described in which the acetalization at temperatures Ti of + 12 ° C or +20 0 C is initiated and continued at temperatures T 2 of +60 0 C or +30 0 C. However, only products with degrees of acetalization of ⁇ 80 mol% are obtained.
• EP 1384732 Al is recommended to initiate the acetalization at a temperature Ti of 0 0 C and then continue at temperature T 2 of + 25 ° C and in EP 0,150,293 it is recommended to acetalization at a temperature of +14 Ti, 4 ° C and continue at a temperature T 2 of +40 0 C.
• the disadvantage of these methods is that acetalization levels of> 70 mol% in the case of EP 1 384 732 A1 result in no product precipitation and in the case of EP 0 150 293 relatively finely divided products in the range from 25 to 75 ⁇ m mean particle size are obtained.
• the invention relates to highly acetalized, coarse-grained polyvinyl acetoacetals having an acetalization degree of> 80 mol% and a mean grain size of> 100 ⁇ m obtainable by acetalization of partially or fully hydrolyzed polyvinyl nyl esters having a degree of hydrolysis of> 70 mol% with acetaldehyde. hyd, characterized in that the acetalization at a temperature I 1 of 0 0 C ⁇ _ I 1 ⁇ _ +20 0 C is initiated and is then continued at a temperature T2 of> + 40 0 C, wherein the temperature T 2 is held for a period of 0.05 to 4 hours and the acetalization is carried out in a closed reactor.
• Another object of the invention is a method for
• Suitable partially hydrolyzed or fully saponified polyvinyl esters are derived from vinyl ester polymers containing 70 to 100 mol% of vinyl ester units.
• Suitable vinyl esters are vinyl esters of unbranched or branched carboxylic acids having 1 to 15 carbon atoms.
• Preferred vinyl esters are vinyl acetate, vinyl propionate, vinyl butyrate, vinyl 2-ethylhexanoate, Vinyl laurate, 1-methylvinyl acetate (isopropenyl acetate), vinyl pivalate and vinyl esters of C-C-branched monocarboxylic acids having 5 to 11 C atoms, for example VeoVa9 R or VeoValO R (trade name of the company Resolution).
• Vinyl acetate is particularly preferred.
• one or more monomers from the group comprising methacrylic acid esters and acrylic esters of alcohols having 1 to 15 carbon atoms, olefins, dienes, vinylaromatics and vinyl halides may optionally also be copolymerized.
• Suitable monomers from the group of the esters of acrylic acid or methacrylic acid are esters of unbranched or branched alcohols having 1 to 15 C atoms.
• Preferred methacrylic esters or acrylic esters are methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, n-, iso- and t-butyl acrylate, n-, iso- and t-butyl methacrylate, 2-ethylhexyl acrylate, norbornyl acrylate.
• Particularly preferred are methyl acrylate, methyl methacrylate, n-, iso- and t-butyl acrylate, 2-ethylhexyl acrylate and norbornyl acrylate.
• Suitable dienes are 1,3-butadiene and isoprene.
• Examples of polymerizable olefins are ethene and propene.
• vinylaromatics styrene and vinyltoluene can be copolymerized.
• vinyl halides usually vinyl chloride, vinylidene chloride or vinyl fluoride, preferably vinyl chloride, are used. The proportion of these comonomers is calculated so that the proportion of vinyl ester monomer is> 70 mol% in the vinyl ester polymer.
• further comonomers may be contained in a proportion of preferably 0.02 to 20 wt .-%, based on the total weight of the vinyl ester polymer.
• comonomers are ethylenically unsaturated mono- and dicarboxylic acids, preferably crotonic acid, itaconic acid, fumaric acid and maleic acid; further ethylenically unsaturated carboxylic acid amides and nitrites, preferably N-vinylformamide; also cyclic amides which carry an unsaturated group on the nitrogen, such as N-vinylpyrrolidone; Mono- and diesters of fumaric acid and maleic acid such as the diethyl and diisopropyl esters and maleic anhydride, ethylenically unsaturated sulfonic acids or salts thereof, preferably vinylsulfonic acid.
• quaternary ammonium chloride DABMAC
• 3-trimethylammoniumpropyl (meth) acrylamide chloride MATAC
• 2-trimethylammoniumethyl (meth) acrylate chloride cationic monomers
• Hilfsmonomere vinyl ethers and vinyl ketones are cationic monomers such as diallyldimethylammonium chloride (DADMAC), 3-trimethylammoniumpropyl (meth) acrylamide chloride (MAPTAC) and 2-trimethylammoniumethyl (meth) acrylate chloride.
• Suitable comonomers are also polymerizable silanes or mercaptosilanes. Preference is given to ⁇ -acrylic or ⁇ -methacryloxypropyltri (alkoxy) silanes, ⁇ -methacryloxymethyltri (alkoxy) silanes, ⁇ -methacryloxypropylmethyldi (alkoxy) silanes, vinylalkyldi- (alkoxy) silanes and vinyltri (alkoxy) silanes, where Alkoxy groups, for example methoxy, ethoxy, methoxyethylene, ethoxyethylene, methoxypropylene glycol ether or ethoxypropylene glycol ether radicals can be used.
• vinyltrimethoxysilane vinyltriethoxysilane, vinyltriopropoxysilane, vinyltriisopropoxysilane, vinyltris (1-methoxy) isopropoxysilane, vinyltributoxysilane, vinyltriacetoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, methacryloxymethyltrimethoxysilane, 3-methacryloxypropyltris (2-methoxyethoxy ) silane, vinyltrichlorosilane, vinylmethyldichlorosilane, vinyltris (2-methoxyethoxy) silane, trisacetoxyvinylsilane, 3- (triethoxysilyl) propylsuccinic anhydride silane. Also preferred are 3-mercaptopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane and 3-mercaptopropylmethyld
• precrosslinking comonomers such as polyethylenically unsaturated comonomers, for example divinyl adipate, diallyl maleate, allyl methacrylate, butanediol diacrylate or triallyl cyanurate, or postcrosslinking comonomers, for example acrylamidoglycolic acid (AGA), methyl acrylamido glycolic acid methyl ester (MAGME), N-methylolacrylamide (NMA), N- Methylolmethacrylamid, N-methylolallyl carbamate, alkyl ethers such as isobutoxy ether or esters of N-methylolacrylamide, N-methylolmethacrylamide and N-Methylolallylcarbamats.
• AGA acrylamidoglycolic acid
• MAGME methyl acrylamido glycolic acid methyl ester
• NMA N-methylolacrylamide
• NMA N- Methylol
• vinyl ester polymers are commercially available or can be prepared in a known manner by means of polymerization; preferably by bulk polymerization, suspension polymerization or by polymerization in organic solvents, more preferably in alcoholic solution.
• Suitable solvents and regulators are, for example, methanol, ethanol, propanol, isopropanol.
• the polymerization is carried out under reflux at a temperature of 40 0 C to 100 0 C and radically initiated by addition of common initiators.
• Examples of common initiators are percarbonates such as cyclohexyl peroxydicarbonate, azo initiators or peresters such as t-butylperneodecanoate or t-butyl perpivalate.
• the adjustment of the molecular weight can be carried out in a known manner by adding regulators, by the solvent content, by varying the initiator concentration and by varying the temperature. After completion of the polymerization, the solvent and optionally excess monomer and regulator can be distilled off.
• the transesterification or saponification of the vinyl ester polymers is carried out in a manner known per se, for example by the belt or kneader process, in the alkaline or acidic state with the addition of acid or base.
• the vinyl ester solid resin is dissolved in alcohol, for example, methanol, adjusting a
• the transesterification or hydrolysis is preferably carried out in the basic, for example by adding NaOH, KOH or NaOCH 3 .
• the base is generally used in an amount of 1 to 5 mol% per mole of ester units.
• the transesterification or hydrolysis is carried out at temperatures of 20 0 C to 70 0 C.
• the reaction mixture is optionally neutralized, the solvent is distilled off and the polyvinyl alcohol is obtained as a powder or granules.
• the polyvinyl alcohol can also be obtained by successively adding water while distilling off the solvent as an aqueous solution.
• Fully hydrolyzed polyvinyl esters are understood as meaning those polymers whose degree of hydrolysis is> 96 mol%.
• Partially hydrolysed polyvinyl esters are understood to mean those having a degree of hydrolysis of> 70 mol% and ⁇ 96 mol%.
• the partially or fully-soaped vinyl ester polymers preferably have a degree of hydrolysis of from 70 mol% to 99.9 mol%, particularly preferably from 90 mol% to 99.9 mol%.
• the viscosity of the polyvinyl alcohol (DIN 53015, Hoppler method, 4% solution in water) is from 1 to 40 mPas, preferably from 1 to 30 mPas, and serves as a measure of the molecular weight and the degree of polymerization of the partially or completely hydrolyzed polyvinyl esters.
• the degree of polymerization of the polyvinyl alcohol used is preferably at least 100.
• acetaldehyde is used, which can also be used in the form of its half or full acetals or its aldehyde hydrates.
• the amount of acetaldehyde added depends on the desired degree of acetalization. Usually, an excess of acetaldehyde over the theoretical amount is used in the inventive method. Preferably, the degree of acetalization is> 83 mol%.
• the partially or completely hydrolyzed polyvinyl esters are preferably taken up in aqueous medium.
• a solid content of the aqueous solution of 4 to 30 wt .-% is set.
• the acetalization takes place in the presence of acidic catalysts such as hydrochloric acid, sulfuric acid, nitric acid or phosphoric acid.
• the content of acidic catalyst depends on the desired reaction rate, the catalytic effect of the catalyst, the desired degree of acetalization and the desired product purity.
• hydrochloric acid When hydrochloric acid is used, a content of acidic catalyst of more than 2% by weight of hydrochloric acid, based on the total reaction mixture but of less than 12% by weight of hydrochloric acid, based on the entire reaction mixture, has proved to be advantageous. Particularly advantageous for the erfindungsge- Permitted method was a content of 3 to 8 wt .-% hydrochloric acid, based on the total reaction mixture.
• the acetalization can be carried out in various ways: polyvinyl alcohol, acidic catalyst and water can be initially introduced and the acetaldehyde added at the start of the reaction at various metering rates.
• polyvinyl alcohol, acidic catalyst and water can be initially introduced and the acetaldehyde added at the start of the reaction at various metering rates.
• the acidic catalyst may be added to trigger some of the reactants polyvinyl alcohol, water and acetaldehyde or to the entire amount of the reactants polyvinyl alcohol, water and acetaldehyde at various dosing rates to initiate the acetalization.
• the reaction mixture is cooled to a temperature I 1 of 0 0 C ⁇ _ I 1 ⁇ _ + 20 0 C, preferably from + 2 ° C ⁇ _ I 1 ⁇ + 16 ° C cooled.
• the acetalization reaction is started by adding the acetaldehyde, or its half or full acetal. Preferably, the batch is kept for 0.5 to 4 hours in this temperature range.
• the batch is heated to a temperature T 2 of> + 40 0 C, preferably> _ + 45 ° C, more preferably + 40 0 C ⁇ T 2 ⁇ + 55 ° C or + 45 ° C £ T 2 £ +50 0 C heated and held at this temperature for 0.05 to 4 hours.
• T 2 a temperature of> + 40 0 C, preferably> _ + 45 ° C, more preferably + 40 0 C ⁇ T 2 ⁇ + 55 ° C or + 45 ° C £ T 2 £ +50 0 C heated and held at this temperature for 0.05 to 4 hours.
• the polyvinyl acetacetal according to the invention Due to the coarser grain shape, the polyvinyl acetacetal according to the invention has a higher bulk density, significantly lower dust content and improved flowability. All this is advantageous for lower transportation costs, better utilization of storage capacity and simplified handling in the preparation of solutions of the polyvinyl acetal.
• the coarser product particles are also less prone to agglomeration in solvents and therefore the rate of dissolution of the polyvinyl acetal is also significantly improved.
• the highly acetalized, coarse-grained polyvinyl acetoacetals are particularly suitable for use as binders in printing inks.
• Suitable printing ink formulations are known to the person skilled in the art and generally contain from 5 to 50% by weight of pigment fraction, for example diazo or phthalocyanine.
• Pigments 4 to 25 wt .-% polyvinyl acetal binders and solvents, for example, alcohols such as ethanol or esters such as ethyl acetate.
• solvents for example, alcohols such as ethanol or esters such as ethyl acetate.
• other additives such as retarders, adhesion promoters, plasticizers and other additives, such as fillers or waxes may be included.
• the highly acetalized, coarse-grained polyvinylacetacetals are also very well suited for laminated safety glass and glass composites, high-security glass or pane foils.
• the highly acetalized, coarse polyvinyl acetoacetals can also be used as binders in aqueous based paints or find advantageous use on the basis of organic solvents, for example as a binder for the inner coating of cans. Further fields of use of the highly acetalized, coarse-grained polyvinyl acetoacetals are the use as binders in corrosion inhibitors. Furthermore, the highly acetalized, coarse-grained polyvinyl acetoacetals are also suitable as binders in the ceramics industry, especially as binders for ceramic granules. To mention is also the use as a binder for ceramic powder and metal powder in the injection molding (powder injection molding).
• the highly acetalized, coarse polyvinyl acetoacetals can also be used as binders for photographic films.
• they can be used as binders for photothermographic materials, such as thermal transfer sheets.
• Such films generally consist of a substrate film and a thermal transfer layer, wherein the polyvinyl acetal cetal is used as a binder.
• the original was cooled with stirring to + 16 ° C (temperature Ti). Subsequently, 3.8 kg of acetaldehyde were added over a period of 30 minutes. After another 60 minutes reaction time at + 16 ° C, the temperature was increased over a period of 300 minutes to 50 0 C and held this temperature T 2 for a further 5 minutes.
• the product was then filtered, washed with distilled water and resuspended in water. Existing residues of the acidic catalyst were neutralized with NaOH. Finally, the product was again filtered off, washed again with distilled water and then dried to a solids content of at least 98.5% by weight.
• Example 3 In a closed reactor, an aqueous solution of 5.5 kg of a fully hydrolysed polyvinyl alcohol, viscosity 5.4 mPas (DIN 53015; Höppler method, 4% aqueous solution, degree of polymerization 850, Mw about 38,000, degree of hydrolysis 98.1 mol%) in 56.2 kg of water with 34.5 kg of 20% hydrochloric acid solution. The original was cooled with stirring to +14 0 C (temperature Ti). Subsequently, 3.8 kg of acetaldehyde were added over a period of 30 minutes. After 60 minutes of additional reaction time at + 14 ° C the temperature was raised over a period of 300 minutes at 50 0 C and this temperature T 2 held for another 5 minutes.
• Table 1 summarizes the most important starting data and the most important analytical results of the examples and comparative examples for better clarity.
• Examples 1 to 4 show that in the production of polyvinyl acetal, regardless of the temperature Ti at which the acetalization is triggered by the continuation of the reaction at a temperature T 2 of> + 40 0 C in a closed reactor, an average particle size of> 100 ⁇ m and an acetalization degree of> 80 mol%. The products are all clearly soluble in methyl ethyl ketone.
• Comparative Example 1 shows that with a comparable formulation and similar reaction procedure as in Examples 1, 2 and 4, but at a temperature T 2 of +30 0 C, in a closed reactor, although a high degree of acetalization of 84.2 mol%, but still only a relatively fine grain of 40 microns average grain size can be obtained.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Organic Chemistry (AREA)
• Ceramic Engineering (AREA)
• General Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Manufacturing & Machinery (AREA)
• Inorganic Chemistry (AREA)
• Materials Engineering (AREA)
• Structural Engineering (AREA)
• Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
• Paints Or Removers (AREA)
• Inks, Pencil-Leads, Or Crayons (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (1)

Family

ID=38353646

Family Applications (1)

Country Status (8)

Families Citing this family (4)

Citations (2)

Family Cites Families (8)

• 2006
  • 2006-06-01 DE DE102006025707A patent/DE102006025707A1/de not_active Withdrawn
• 2007
  • 2007-05-25 EP EP07729508A patent/EP2029632A1/de not_active Ceased
  • 2007-05-25 WO PCT/EP2007/055079 patent/WO2007137999A1/de not_active Ceased
  • 2007-05-25 SG SG2011036811A patent/SG172612A1/en unknown
  • 2007-05-25 JP JP2009512557A patent/JP5264712B2/ja not_active Expired - Fee Related
  • 2007-05-25 US US12/302,104 patent/US8309675B2/en not_active Expired - Fee Related
  • 2007-05-25 CN CN2007800199704A patent/CN101454354B/zh not_active Expired - Fee Related
  • 2007-05-29 TW TW096119124A patent/TW200801056A/zh not_active IP Right Cessation

Patent Citations (2)

Also Published As

Similar Documents

Legal Events