HK1081215A - Size composition - Google Patents

Description

Sizing composition

no marking

Cross reference to related patent applications

German patent application No. 102004002527.4, filed in the present patent application claims 2004-01-16, has priority under 35 u.s.c. § 119(a) - (d).

Technical Field

The present invention relates to novel sizing compositions which are stable to thermal yellowing, their preparation and their use.

Background

In sizing glass (sizing of glass) and carbon fibers, PU dispersions are used in particular as binders in sizing compositions, as described in EP-A792900.

The undesirable thermal yellowing of the resulting coating often occurs due to the relatively high temperatures, in some cases well above 200 ℃, introduced in the coating and drying operations and in the synthesis of the sized glass fibers into the polymer matrix.

The prior art has disclosed a number of stabilizers and additives which reduce the thermal yellowing of adhesives. However, in the field of aqueous PU dispersants, these systems have an inadequate effect on inhibiting yellowing, or they lead to poor dispersion and coating properties, such as poor stress-strain properties or poor compatibility with other coating or sizing components. Known additives also tend to migrate from the resulting coating and, as a result, undesirable fogging and tail off in the yellow stabilization occur over time.

U.S. Pat. No. 5,137,967 describes the preparation of PU dispersions containing carboxylic acid salts which are stable to thermal yellowing and are obtainable by known methods of prepolymer mixing. For stability to yellowing, hydrazine is used to chain extend the prepolymer and Dimethylaminoethanol (DMAE) is used as the carboxylic acid group neutralizing amine.

DE 3238169 describes a process for preparing PU dispersions using hydrazine or hydrazide as additive or as chain extender. In addition to anionic, carboxylate-functionalized PU dispersions are disclosed which result from a prepolymer mixing process.

In general, hydrazine and hydrazide as chain extenders in polyurethanes are known, for example, from U.S. Pat. No. 4,41, 679 or DE-A2314513. In some cases they are also used in mixtures with other chain extenders such as diamines (U.S. Pat. No. 3,3415768). They are used to improve the flexibility, hardness, resistance and drying of the coating.

It is an object of the present invention to provide a sizing composition that is capable of stabilizing or reducing thermal yellowing compared to prior art sizing.

Disclosure of Invention

The present invention relates to a sizing composition comprising I) one or more polyurethane-polyurea dispersions (PU dispersions); II) optionally further comprising a film-forming resin; and III) optionally a crosslinking agent. I) The PU dispersion in (a) was obtained from: A) preparing an NCO-containing polyurethane prepolymer by reacting: A1) polyisocyanates with A2) polymeric polyols and/or polyamines having a number average molecular weight of 400-8000g/mol, A3) optionally low molecular weight compounds having a number average molecular weight of 17-400g/mol, selected from mono-and polyols, mono-and polyamines and aminoalcohols, A4) isocyanate-reactive ionic or potentially ionic hydrophilic compounds and/or A5) isocyanate-reactive non-ionic hydrophilic compounds A6) optionally in an inert solvent, with the proviso that none of the components A1) -A5) contains primary or secondary amine groups; B) dissolving the prepolymer obtained in step A) in an aliphatic ketone or diluting the prepolymer solution if the preparation has been carried out in an inert solvent, optionally with addition of an aliphatic ketone, and C) reacting the remaining free NCO groups of the prepolymer with a chain extender comprising: C1) hydrazine and/or hydrazine hydrate and C2) optionally conform to the components defined under a2), A3), a4) and/or a5), with the proviso that the C2) component compound contains primary and/or secondary amine groups, the total amount of C1) and C2) being such that the chain growth reaches 40 to 200% by weight, the proportion of C1) and C2) being at least 40% of the free isocyanate groups being blocked and/or extended by amino groups by component C1).

The present invention also provides moldings (moulidins) and/or coatings comprising the above-described sizing composition and one or more additives selected from the group consisting of: coupling agents, lubricants, antistatic agents, dyes, pigments, flow aids, light stabilizers, anti-aging agents, UV absorbers, and combinations thereof.

The present invention also provides substrates coated with a coating obtained using the above sizing composition.

The present invention also provides glass fibers wherein the above sizing composition is applied to the glass fibers.

Other than in the operating examples, or where otherwise indicated, all numbers or expressions referring to quantities of ingredients, reaction conditions, etc. used in the specification and claims are to be understood as modified in all instances by the term "about".

The present invention provides sizing compositions that are stable to or reduce thermal yellowing compared to prior art sizes.

Thus, it has been found that sizing based on PU dispersions specifically prepared using hydrazine as a chain extender component achieves the desired properties without the need for special additional stabilizers/additives.

The present invention therefore provides a sizing composition comprising

I) One or more polyurethane-polyurea dispersions (PU dispersions)

II) optionally further comprising a film-forming resin

III) optionally crosslinking agents

IV) auxiliaries and additives, and (b) additives,

characterized in that the PU dispersions used in I) are obtained by:

A) the following were first reacted to prepare an NCO-containing polyurethane prepolymer:

A1) polyisocyanates and

A2) a polymer polyol and/or polyamine having a number average molecular weight of 400-8000g/mol,

A3) optionally low molecular weight compounds having a number average molecular weight of 17 to 400g/mol, selected from the group consisting of mono-and polyols, mono-and polyamines and aminoalcohols,

A4) isocyanate-reactive ionic or potentially ionic hydrophilic compounds and/or

A5) Isocyanate-reactive nonionic hydrophilic compounds

A6) Optionally in the presence of a solvent aliphatic ketone,

with the proviso that none of the components A1) -A5) contain a primary or secondary amine group,

B) dissolving the prepolymer obtained in step A) in an aliphatic ketone or, if the preparation has been carried out in the presence of A6), diluting the prepolymer solution, optionally also adding an aliphatic ketone, and

C) reacting the remaining free NCO groups of the prepolymer with a chain extender comprising:

C1) hydrazine and/or hydrazine hydrate and

C2) optionally compounds according to the definition of A2), A3), A4) and/or A5),

provided that

● component C2) the compound contains primary and/or secondary amine groups,

● C1) and C2) are calculated amounts that result in a chain growth of 40-200%,

and

● C1) and C2) in such a way that at least 40% of the free isocyanate groups are incorporated in the component

C1) End-capping and/or chain-lengthening with amino groups.

Suitable polyisocyanates of the A1) component are the aromatic, araliphatic, aliphatic or cycloaliphatic polyisocyanates known to the person skilled in the art and those which also contain iminooxadiazinedione, isocyanurate, uretdione (uretdione), urethane, allophanate, biuret, urea, oxadiazinetrione, oxazolidinone, acylurea and/or carbodiimide structures. They can be used alone in A1), or in any desired mixture with one another.

Examples of suitable aromatic, araliphatic, aliphatic or cycloaliphatic polyisocyanates are di-and/or triisocyanates having a molecular weight of 140-400g/nol, which are obtained by phosgenation or by phosgene-free processes (phosgene-free processes), such as by thermal urethane cleavage, and those which comprise aliphatically, cycloaliphatically, araliphatically and/or aromatically bonded isocyanate groups, such as, for example, 1, 4-diisocyanatobutane, 1, 5-diisocyanatopentane, 1, 6-diisocyanatohexane (HDI), 2-methyl-1, 5-diisocyanatopentane, 1, 5-diisocyanato-2, 2-dimethylpentane, 2, 4-and/or 2, 4, 4-trimethyl-1, 6-diisocyanatohexane, 1, 10-diisocyanatodecane, 1, 3-and 1, 4-diisocyanatocyclohexane, 1, 3-and 1, 4-bis- (isocyanatomethyl) -cyclohexane, 1-isocyanato-3, 3, 5-trimethyl-5-isocyanatomethyl-cyclohexane (isophorone diisocyanate, IPDI), 4, 4 '-diisocyanatocyclohexylmethane (Desmodur * W, Bayer AG, Leverkusen), 4-isocyanatomethyl-1, 8-octane diisocyanate (triisocyanatononane, TIN), omega' -diisocyanato-1, 3-dimethyl-cyclohexane (H, N₆XDI), 1-isocyanato-1-methyl-3-isocyanatomethylcyclohexane, 1-isocyanato-1-methyl-4-isocyanatomethylcyclohexane, bis- (isocyanatomethyl) -norbornane, 1, 5-naphthalene diisocyanate, 1, 3-and 1, 4-bis- (2-isocyanato-prop-2-yl) -benzene (TMXDI), 2, 4-and 2, 6-diisocyanatotoluene (TDI), in particular technical-grade mixtures of 2, 4-and 2, 6-isomers and 2 isomers, 2, 4 '-and 4, 4' -diisocyanatodiphenylmethane (MDI), 1, 5-diisocyanatonaphthalene, naphthalene, 1, 3-bis- (isocyanatomethyl) -benzene (XDI) and any mixtures with said compounds.

Preference is given to using polyisocyanates or polyisocyanate mixtures of the type mentioned at A1) which contain isocyanate groups which have exclusively aliphatic and/or cycloaliphatic linkages.

Particular preference is given to hexamethylene diisocyanate, isophorone diisocyanate and the isomeric bis- (4, 4' -isocyanatocyclohexyl) methanes and also mixtures thereof.

It is important to prepare prepolymers, the compounds used in A2) to A5) being only such as those which do not contain primary and/or secondary amine functional groups. With regard to chain extension, it is, in contrast, possible to use compounds in C2) which conform to the definitions of components a2) to a5), but which additionally contain primary and/or secondary amine groups.

The polymeric polyols or polyamines according to the definition of component A2) are generally selected from the group consisting of polyacrylates, polyesters, polylactones, polyethers, polycarbonates, polyestercarbonates, polyacetals, polyolefins and polysiloxanes and have a preferred functionality in relation to the NCO-reactive functionality of 1.5 to 4.

It is particularly preferred that the polymeric polyol is one having a number average molecular weight of 600-2500g/mol and an OH functionality of 2-3.

The hydroxyl-containing polycarbonates according to the definition of component A2) are obtained by reaction of carbonic acid derivatives, for example diphenyl carbonate, dimethyl carbonate or phosgene, with diols.

Examples of suitable such diols include ethylene glycol, 1, 2-and 1, 3-propanediol, 1, 3-and 1, 4-butanediol, 1, 6-hexanediol, 1, 8-octanediol, neopentyl glycol, 1, 4-dihydroxymethylcyclohexane, 2-methyl-1, 3-propanediol, 2, 4-trimethylpentane-1, 3-pentanediol, dipropylene glycol, polypropylene glycol, dibutylene glycol, polybutylene glycol, bisphenol A, tetrabromobisphenol A or another lactone-modified diol. The diol component preferably contains from 40 to 100% by weight of hexanediol, preferably 1, 6-hexanediol and/or hexanediol derivatives, particularly preferably those which, in addition to the terminal hydroxyl groups, carry ether or ester groups, for example products obtained by reacting 1mol of hexanediol with at least 1mol, preferably 1 to 2mol, of caprolactone in accordance with DE-A1770245 or by self-etherification of hexanediol to give di-or trihexylene glycol. The preparation of these derivatives is disclosed, for example, in DE-A1570540. Polyether polycarbonate diols as described in DE-A3717060 may also be used.

The hydroxyl polycarbonates should preferably be linear, however, they may optionally be lightly branched by the incorporation of polyfunctional components, in particular low molecular weight polyols. Those suitable examples are glycerol, trimethylolpropane, 1, 2, 6-hexanetriol, 1, 2, 4-butanetriol, trimethylolpropane, pentaerythritol, p-cyclohexanediol, mannitol and sorbitol, methyl glycosides and 1, 3, 4, 6-dianhydrohexitols, which are suitable for this purpose.

Suitable polyether polyols according to the definition of component a2) are the polytetramethylene glycol polyethers known per se in polyurethane chemistry and can be prepared via cationic ring-opening polymerization of, for example, tetrahydrofuran.

Other suitable polyether polyols are polyethers, for example polyols prepared from styrene oxide, propylene oxide, butylene oxide or epichlorohydrin, in particular polyols prepared from propylene oxide, using starter molecules.

Examples of suitable polyester polyols falling under the definition of component A2) include reaction products of polyhydric, preferably dihydric and optionally additionally trihydric alcohols with polybasic, preferably dibasic carboxylic acids. Instead of the free polycarboxylic acids, it is also possible to use the corresponding polycarboxylic anhydrides or corresponding polycarboxylic esters of lower alcohols or mixtures thereof for preparing the polyesters. In fact, the polycarboxylic acids may be aliphatic, cycloaliphatic, aromatic and/or heterocyclic, and optionally substituted, for example by halogen atoms, and/or unsaturated.

The compounds according to the definition of component A3) may be added to the process of the invention in order to end-cap the polyurethane prepolymer.

Suitable compounds for this purpose are, for example, monofunctional fatty alcohols or monoamines having from 1 to 18 carbon atoms having the stated molecular weights, for example ethanol, N-butanol, ethylene glycol monobutyl ether, 2-ethylhexanol, 1-octanol, 1-dodecanol, 1-hexadecanol, diethylamine, dibutylamine, ethanolamine, N-methylethanolamine, N-diethanolamine, the amines of Jeffamine * M series (Huntsman Corp. Europe, Belgium) or the amino-functional polyethylene and polypropylene.

Furthermore, polyols, aminopolyols or polyamines having a number average molecular weight of less than 400g/mol can be used in the process of the present invention. Examples of such substances which may be mentioned are:

a) alkanediols and/or triols, such as ethylene glycol, 1, 2-and 1, 3-propanediol, 1, 4-and 2, 3-butanediol, 1, 5-pentanediol, 1, 3-dimethylpropanediol, 1, 6-hexanediol, neopentyl glycol, 1, 4-cyclohexanedimethanol, 2-methyl-1, 3-propanediol, 2-ethyl-2-butylpropanediol, trimethylpentanediol, positionally isomeric diethyloctanediols, 1, 2-and 1, 4-cyclohexanediols, hydrogenated bisphenol A [2, 2-bis (4-hydroxycyclohexyl) propane ], (2, 2-dimethyl-3-hydroxypropyl) 2, 2-dimethyl-3-hydroxypropionate, trimethylolethane, glycerol, and mixtures thereof, A trimethylolpropane or a glycerol, and a mixture of the trimethylolpropane and the glycerol,

b) ether glycols, such as diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, 1, 3-butanediol, or hydroquinone dihydroxyethyl ether,

c) ester diols of the general formulae (I) and (II)

HO-(CH₂)_x-CO-O-(CH₂)_y-OH (I)，

HO-(CH₂)_x-O-CO-R-CO-O(CH₂)_x-OH (II)，

Wherein R is an alkylene or arylene group having 1 to 10 carbon atoms, preferably 2 to 6 carbon atoms,

x is 2 to 6, and

y is a number of from 3 to 5,

for example, delta-hydroxybutyl-epsilon-hydroxyhexanoate, omega-hydroxyhexyl-gamma-hydroxybutyrate, adipic acid (. beta. -hydroxyethyl) ester and terephthalic acid bis (. beta. -hydroxy-ethyl) ester, and

d) di-and polyamines, such as 1, 2-diaminoethane, 1, 3-diaminopropane, 1, 6-diaminohexane, 1, 3-and 1, 4-phenylenediamine, 4, 4 '-diphenylmethanediamine, isophoronediamine, isomer mixtures of 2, 2, 4-and 2, 4, 4-trimethylhexamethylenediamine, 2-methyl-pentamethylenediamine, diethylenetriamine, 1, 3-and 1, 4-xylylenediamine, alpha' -tetramethyl-1, 3-and-1, 4-xylylenediamine and 4, 4-diamino-dicyclohexylmethane, amino-functional polyethylene oxides or propylene oxides commercially available from Jeffamine *, D series (huntsman Corp. Europe, Belgium), Diethylenetriamine and triethylenetetramine. Diamines suitable for use in the present invention may also be substituted hydrazines, such as N-methylhydrazine, N' -dimethylhydrazine and their homologues and dihydrazides of adipic acid, beta-methyladipic acid, sebacic acid, hydroxypropionic acid and terephthalic acid, urea aminoalkylene hydrazides, such as beta-urea aminopropionic acid hydrazide (e.g. DE-A1770591), urea aminoalkylene-carbazyl hydrazine esters (carbazin esters), such as 2-urea aminoethylcarbazyl hydrazine esters (e.g. DE-A1918504), or further aminosemicarbazide compounds, such as beta-aminoethylurea aminocarbonate (e.g. DE-A1902931).

Ionic and potentially ionic hydrophilic compounds are meant to be all of the following: containing at least one isocyanate-reactive group and at least one functionality, e.g. -COOY, -SO₃Y、-PO(OY)₂(Y is, for example, H, NH₄ ⁺Metal cation), -NR₂、-NR₃ ⁺(R ═ H, alkyl, aryl) which interacts with aqueous media into the optional pH-side chain dissociation equilibrium, and as such may have negative, positive or neutral charges.

Preferably, the reactive isocyanate group is a hydroxyl group or an amino group.

Suitable ionic or potentially ionic hydrophilic compounds are those which conform to the definition of component A4, for example, mono-and dihydroxycarboxylic acids, mono-and diaminocarboxylic acids, mono-and dihydroxysulfonic acids, mono-and diaminosulfonic acids and also mono-and dihydroxyphosphonic acids or mono-and diaminophosphonic acids andsalts thereof, such as dimethylolpropionic acid, dimethylolbutyric acid, hydroxypivalic acid, N- (2-aminoethyl) -beta-alanine, 2- (2-aminoethylamino) -ethanesulfonic acid, ethylenediamine-propanesulfonic acid or ethylenediamine-butanesulfonic acid, 1, 2-or 1, 3-propylenediamine-beta-ethanesulfonic acid, malic acid, citric acid, glycolic acid, lactic acid, glycine, alanine, taurine, lysine, 3, 5-diaminobenzoic acid, the adduct of IPDI with acrylic acid (EP-A0916647 example 1) and alkali metal and/or ammonium salts thereof; adducts of sodium bisulfite and but-2-ene-1, 4-diol, polyether sulfonates, 2-butanediol and NaHSO₃Propoxylated adducts of (A) and compounds containing structural units which can be converted into cationic groups, amine-based structural units, such as N-methyldiethanolamine, for example, can likewise be used as hydrophilic system components (for example, in DE-A2446440, pages 5 to 9, formulae I-III). It is also possible to use Cyclohexylaminopropanesulfonic Acid (CAPS), such as the compounds defined in WO01/88006, for example, according to component A4).

Preferred ionic or potentially ionic compounds are those having carboxyl or carboxylate and/or sulfonate groups and/or ammonium groups.

Particularly preferred ionic compounds are those which contain carboxylate and/or sulfonate groups as ionic or potentially ionic groups, such as salts of N- (2-aminoethyl) - β -alanine, 2- (2-aminoethylamino) ethanesulfonic acid or of an adduct of PIDI and acrylic acid (EP-A0916647, example 1) and salts of dimethylolpropionic acid.

Suitable nonionically hydrophilicizing compounds according to the definition of component A5), for example polyoxyalkylene ethers which contain at least one hydroxyl or amino group. These polyethers comprise from 30% to 100% by weight of structural units derived from ethylene oxide. Including linear polyethers having a functionality of 1 to 3, and also compounds of the formula (III) are suitable.

Wherein the content of the first and second substances,

R¹and R²Independently of one another, each represents a divalent aliphatic, cycloaliphatic or aromatic radical having 1 to 18 carbon atoms which may be interrupted by oxygen and/or nitrogen atoms, and

R³represents an alkoxy-terminated polyethylene oxide group.

Nonionic hydrophilic compounds also include, for example, monohydropolyalkylene oxide polyether alcohols which contain an average of from 5 to 70, preferably from 7 to 55, ethylene oxide units per molecule and are obtained in a conventional manner by alkoxylation of suitable starter molecules (for example in Ullmanns encyclopedie der technischen Chemie, 4th edition, Volume 19, Verlag Chemie, Weinhiemp.31-38).

Suitable starter molecules are, for example, saturated monoalcohols, such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, the isomeric pentanols, hexanols, octanols and nonanols, n-decanol, n-dodecanol, n-tetradecanol, n-hexadecanol, n-octadecanol, cyclohexanol, the isomeric methylcyclohexanols or hydroxymethylcyclohexane, 3-ethyl-3-hydroxy-methyloxetane (methyloxyethane) or tetrahydrofurfuryl alcohol, diethylene glycol monoalkyl ethers, such as diethylene glycol monobutyl ether, e.g. unsaturated alcohols, such as allyl alcohol, 1-dimethylallyl alcohol or oleyl alcohol, aromatic alcohols, such as phenol, the isomeric cresols or methoxyphenols, araliphatic alcohols, such as benzyl alcohol, anisyl alcohol or cinnamyl alcohol; secondary monoamines, such as dimethylamine, diethylamine, dipropylamine, diisopropylamine, dibutylamine, bis- (2-ethylhexyl) -amine, N-methyl-and N-ethyl-cyclohexylamine or dicyclohexylamine, and heterocyclic secondary amines, such as morpholine, pyrrolidine, piperidine or 1H-pyrazole. Preferred starter molecules are saturated monoalcohols. Particular preference is given to using diethylene glycol monobutyl ether as starter molecule.

Alkylene oxides suitable for the alkoxylation reaction are, in particular, ethylene oxide and propylene oxide, which can be used in the alkoxylation reaction in any order or in mixtures.

The polyalkylene oxide polyether alcohols may be pure polyethylene oxide polyethers or mixed polyalkylene oxide polyethers whose alkylene oxide units consist of at least 30 mol%, preferably at least 40 mol%, of ethylene oxide units. Preferred nonionic compounds are monofunctional mixed polyalkylene oxide polyethers which contain at least 40 mol% ethylene oxide units and not more than 60 mol% propylene oxide units.

In the present process, preference is given to using combinations of ionic and nonionic hydrophilicizing agents as defined under components A4) and A5). Combinations of nonionic and anionic hydrophilic agents are particularly preferred.

Chain extension in step C) is achieved using hydrazine and/or its hydrates as component C1). Preferably, hydrazine monohydrate is used.

If desired, further chain extenders can be used in component C2). These substances conform to the definition of the compounds suitable for use in A2) -A5), with the proviso that the compound used in C2) contains-NH₂And/or NH groups.

In the process, preference is given to using from 7 to 45% by weight of component A1), from 50 to 91% by weight of component A2), from 0 to 30% by weight of component A3), from 0 to 12% by weight of component A4), from 0 to 15% by weight of component A5), from 0.1 to 5.0% by weight of component C1) (based on pure hydrazine, N₂H₄) 0 to 15% by weight of component C2), the total amount of A4) and A5) being 0.1 to 27% by weight, the total amounts of all components adding to 100% by weight.

In the process, in particular, from 10 to 30% by weight of component A1), from 65 to 90% by weight of component A2), from 0 to 10% by weight of component A3), from 0 to 10% by weight of component A4), from 0 to 15% by weight of component A5), from 0.1 to 3.0% by weight of component C1) (based on pure hydrazine, N₂H₄) 0 to 10% by weight of component C2), the total amount of A4) and A5) being 0.1 to 25% by weight, the total amounts of all components adding to 100% by weight.

Particular preference is given to 8 to 27% by weight of component A1), 65 to 85% by weight of component A2), 0 to 8% by weight of component A3), 0 to 10% by weight of component A4), 0 to 15% by weight of component A5), 1.0 to 2.5% by weight of component C1) (based on pure hydrazine, N₂H₄) 0 to 8% by weight of component C2), the total amount of A4) and A5) being 0.1 to 25% by weight, the total amounts of all components adding to 100% by weight.

The process for preparing the aqueous PU dispersions can be carried out in one or more stages, either in homogeneous phase or, in the case of a multistage reaction, partly in dispersed phase. Complete or partial completion of the polyaddition with A1) -A5) is followed by a step of dispersing, emulsifying or dissolving. Optionally followed by further polyaddition or modification in the disperse phase.

The aqueous PU dispersions can be prepared using the prior art acetone process or modifications thereof. A summary of these methods is described in Methoden der organischen Chemie (Houben-Weyl addition and supplement Volumes to the 4th Edition, H.Bartland J.Falbe, Stuttgart, New York, Thieme 1987, pp.1671-1682). The acetone process is preferred.

In general, in process step A) for preparing the polyurethane prepolymers, components A2) to A5) which should not contain any primary or secondary amine groups and polyisocyanate component A1) are introduced as starting materials in whole or in part and optionally diluted in a water-miscible but isocyanato-inert solvent A6) and heated to elevated temperature, preferably from 50 to 120 ℃.

Suitable solvents are the customary aliphatic ketone-functional solvents, such as acetone or butanone, for example, which are added not only at the beginning of the preparation but also subsequently if desired. Acetone and butanone are preferred. The reaction may be carried out at atmospheric pressure or under elevated pressure, for example, at a temperature above the atmospheric boiling temperature of a solvent such as acetone.

It is also possible to include in the process, in the starting materials or subsequently, to meter in known catalysts to accelerate the isocyanate addition reaction, such as triethylamine, 1, 4-diazabicyclo [2, 2, 2] octane, dibutyltin oxide, tin dioctoate or dibutyltin dilaurate, tin di (2-ethylhexanoate) or other organometallic compounds. Dibutyl tin dilaurate is preferred.

The components A1) to A5) which were not added at the beginning of the reaction were then metered in.

In step A) of preparing the polyurethane prepolymer, the molar ratio of isocyanate groups to isocyanate-reactive groups is from 1.0 to 3.5, preferably from 1.1 to 3.0, more preferably from 1.1 to 2.5.

Components A1) to A5) the reaction to prepare the prepolymer is partial or complete, preferably complete. The extent of the reaction is generally monitored by the NCO content of the reaction mixture. It can be sampled not only by spectroscopic tests, such as infrared or near infrared spectroscopy, but also by measurement of refractive index or by chemical analysis such as titration. In this way, the product polyurethane prepolymer containing free isocyanate groups or its product in solution is obtained.

The preparation of the polyurethane prepolymers from A1) and A2) to A5) is carried out continuously or simultaneously, if not carried out in the molecule of the starting materials, partly or completely by anionic and/or cationic dispersing groups to form salts. In the case of anionic groups, bases are used, such as ammonia, ammonium carbonate, or ammonium bicarbonate, trimethylamine, triethylamine, tributylamine, diisopropylethylamine, dimethylethanolamine, diethylethanolamine, triethanolamine, potassium hydroxide or sodium carbonate, preferably triethylamine, triethanolamine, dimethylethanolamine or diisopropylethylamine.

The molar amount of base is 50-100%, preferably 60-90%, of the molar amount of anionic groups. In the case of cations, dimethyl sulfate or succinic acid is used. If only nonionically hydrophilic compounds A5 containing ether groups are used), the neutralization step is omitted. Neutralization can be carried out simultaneously with dispersion using dispersing water (dispersing water) already containing a neutralizing agent.

Then, in step B) of the process according to the invention, if the prepolymer is not dissolved or only partially dissolved in A), the prepolymer obtained is dissolved by means of an aliphatic ketone, such as acetone or butanone.

Component C1) and possibly NH in step C) of the process according to the invention₂-and/or NH functional component C2) with the remaining isocyanate groups. The chain extension/termination can be carried out in a solvent before or during dispersion or in water after dispersion.

If the chain extension in C2) is carried out using compounds which conform to the definition of A4) and contain NH₂Or NH groups, the chain extension of the prepolymer preferably being before dispersion.

The degree of chain extension, in other words the equivalent ratio of NCO-reactive groups of the compounds used as chain extension in C1) and optionally C2) to free NCO groups of the prepolymer, is generally from 40 to 200%, preferably from 70 to 180%, more preferably from 80 to 160%, particularly preferably from 101 to 150%, C1) being added in an amount such that at least 40%, preferably at least 50%, more preferably at least 70%, of the NCO groups are reacted with component C1).

Blocking of the prepolymer in C2) may also be carried out additionally using monoamines, such as diethylamine, dibutylamine, ethanolamine, N-methylethanolamine or N, N-diethanolamine.

In the process of the present invention, the amine components C1) and optionally C2) can be used individually or in admixture, optionally in water-diluted or solvent-diluted form, any order of addition of which is in principle possible.

If water or an organic solvent is used as the diluent, the content of the diluent is preferably 70 to 95% by weight.

Preference is given to adding component C1) and compounds which conform to C2) as defined under A4) and then compounds which conform to C2) as defined under A2) and/or A3) for chain extension.

The preparation of the PU dispersions from the prepolymers usually takes place after chain extension (step C). For this purpose, if desired, the dissolved and chain-extended polyurethane polymer is added to the dispersion water with strong shear action, for example with strong stirring, or conversely with stirring, the dispersion water is added to the prepolymer solution. Preferably, water is added to the dissolved prepolymer.

In general, the chain extension can be carried out after the dispersing step by additionally adding further amounts of C1) and C2), but preferably only before the dispersing.

The solvent is generally still present in the dispersion after the dispersing step and is then removed by distillation. Removal during dispersion is also possible.

The dispersions obtained in this way have a solids content of from 10 to 70% by weight, preferably from 25 to 65% by weight, more preferably from 30 to 65% by weight.

Depending on the degree of neutralization and the number of ionic groups, it can be dispersed so finely that it is almost an external feature of a solution, although it can also be a crude formulation, and is also sufficiently stable.

The aqueous PU dispersions obtained can also be modified with polyacrylates. To this end, emulsion polymerization of ethylenically unsaturated monomers, for example esters of (meth) acrylic acid and alcohols having 1 to 18 carbon atoms, styrene, vinyl esters or butadiene, is carried out in these polyurethane dispersions, as described, for example, in DE-A1953348, EP-A0167188, EP-A0189945 and EP-A0308115.

In addition to one or more olefinic double bonds, the monomers may also contain functional groups, such as hydroxyl, epoxy, hydroxymethyl, or acetoacetoxy groups.

Suitable component II) film-forming resins are water-soluble, emulsifiable or dispersible polymers known to the person skilled in the art. Examples are polyester polymers or epoxy-functional polyester polymers, polyurethanes, acrylic polymers, vinyl polymers such as polyvinyl acetate, polyurethane dispersions, polyacrylate dispersions, polyurethane-polyacrylate hybrid dispersions, polyvinyl ether and/or polyvinyl ester dispersions, polystyrene and/or polyacrylonitrile dispersions. The solids content of the film-forming resins is generally from 10 to 95% by weight, preferably from 30 to 95% by weight.

The PU dispersions of component I) and the film-forming resins of component II) may contain groups which are reactive toward the crosslinker component III).

The crosslinking agent of component III) may use a polyisocyanate with an optional blocked NCO group and/or amino crosslinking agent resin such as a melamine resin.

Preference is given to using hydrophilic or hydrophilic (hydrophilicized) water-soluble or water-dispersible blocked polyisocyanates in the crosslinker component III).

In a preferred embodiment of the invention, in addition to component I), at least one crosslinker and/or film-forming resin is used.

Component IV) auxiliaries and additives are added to the sizing composition. They may be coupling agents, lubricants, antistatic agents or other coating additives known to the person skilled in the art, such as dyes, pigments, flow aids, light stabilizers, anti-ageing agents, UV absorbers, etc. These are described in K.L. Loewenstein, "continuous glass fiber production technology", Elsevierscientific Publishing Corp., Amsterdam, London, New York, 1983, pp 243-295.

The coupling agent in IV) may be a known silane coupling agent, such as 3-aminopropyltrimethoxy-and/or-triethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-glycidylpropyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane or 3-methacryloyloxypropyltriethoxysilane. The content of silane coupling agent in the sizing composition of the invention is preferably from 0.05 to 2% by weight, more preferably from 0.15 to 0.85% by weight, based on the entire sizing composition.

The sizing composition of the invention may also comprise one or more nonionic and/or ionic lubricants as part of component IV), such as polyalkylene glycol ethers of fatty alcohols or fatty amines, polyalkylene glycol ethers and glyceryl esters of fatty acids having from 12 to 18 carbon atoms, polyalkylene glycols, higher fatty acid amides of polyalkylene glycols and/or alkylene amines having from 12 to 18 carbon atoms, quaternary nitrogen compounds, imidazolinium salts such as ethoxylates, mineral oils and waxes. The one or more lubricants are preferably used in an amount of 0.05 to 1.5% by weight of the total amount of the sizing composition as a whole.

The sizing composition of the present invention may also comprise one or more antistatic agents as part of component IV). Examples which may be mentioned include lithium chloride, ammonium chloride, Cr (III) salts, organotitanium compounds, arylalkyl sulfates or sulfonates, arylpolyglycol ether sulfonates or quaternary nitrogen compounds. The concentration of the antistatic agent used is preferably 0.01 to 0.8% by weight.

The sizing composition may be prepared by known methods. Water is preferably added to a suitable mixing vessel with stirring, the binder (component I)), the curing agent (component III)), and then the lubricant and any other auxiliary components IV) are added. Then, the pH is adjusted to 5-7 and the hydrolysate of the coupler of component IV) is added. With further stirring for 15 minutes, the sizing composition is ready for use and may optionally be applied after pH adjustment.

The sizing composition may be coated onto a suitable substrate and cured by any suitable method, such as spraying or roll coating.

Suitable substrates are selected from the group consisting of metal, wood, glass fibers, carbon fibers, stone, ceramic minerals, concrete, rigid and flexible plastics of various types, woven and non-woven fabrics, leather, paper, hard fibers, grass and asphalt, and may optionally be provided with a conventional primer prior to sizing. Preferred substrates are glass fibers, carbon fibers, metals, textiles and leather. Particularly preferred substrates are glass fibers.

The types of glass suitable for sizing the glass fibers include not only the types of glass used by the known glass fiber manufacturers, such as E, A, C and S glass according to DIN 1259-1, but also conventional glass fiber products. Among the types of glass used for the production of continuous glass fibers, E glass fibers are very important for reinforcing plastics because they are not affected by alkali, have high tensile strength and high modulus of elasticity.

The method of sizing and the method of preparation and subsequent processing of the glass fibers are known and described, for example, in k.l. loewenstein, "technique for producing continuous glass fibers", elsevier scientific Publishing corp., Amsterdam, London, New York, 1983.

Sizing is generally the coating of glass filaments, drawn rapidly from the bushing, immediately after the curing of the filaments, i.e. even before the drawing-up thereof. In another embodiment, the fibers are sized in a dip tank after the spinning operation. The sized glass fibers may then be chopped, e.g., wet or dry. The final product or intermediate is dried at a temperature of 50-200 deg.C, preferably 90-150 deg.C. In this context, drying is not only the removal of other volatile components, but also, for example, the curing of the sizing component. Sizing to the final coating material only after drying. Preferably, the sized portion comprises from 0.1 to 5.0 weight percent, more preferably from 0.1 to 3.0 weight percent, and even more preferably from 0.3 to 1.5 weight percent of the sized glass fibers.

A wide variety of thermoplastic and curable thermoset polymers can be used as the matrix polymer that can be incorporated into the resulting sized glass fibers. Examples of suitable thermoplastic polymers include the following: polyolefins such as polyethylene or polypropylene, polyvinyl chloride, polymers such as styrene/acrylonitrile copolymers, ABS, polymethacrylates or polyoxymethylene, aromatic and/or aliphatic polyamides such as polyamide-6 or polyamide-6, polycondensates such as polycarbonate, polyethylene terephthalate, liquid-crystalline polyarylates, polyarylene oxides, polysulfones, polyarylene sulfides, polyarylsulfones, polyethersulfones, polyaryl ethers or polyetherketones or polyadducts such as polyurethanes. Examples of polymers that may be mentioned for curing thermosets include the following: epoxy resins, unsaturated polyester resins, phenolic resins, amine resins, polyurethane resins, polyisocyanates, epoxy/isocyanate hybrid resins, furan resins, cyanurate resins, and bismaleimide resins.

Detailed Description

All percentages are by weight unless otherwise stated.

Diaminosulfonate：

NH₂-CH₂CH₂-NH-CH₂CH₂-SO₃Na (45% strength in water)

The solids content is determined in accordance with DIN-EN ISO 3251.

The NCO content is determined volumetrically in accordance with DIN-EN ISO 11909, unless stated otherwise. The yellowness index is determined by the CIELAB method (DIN 5033).

Crosslinker dispersions：

147.4g of a polyisocyanate containing biuret groups and having an NCO content of 23.0% based on 1, 6-diisocyanatohexane (HDI) were added as starting material at 40 ℃. 121.0g of polyether LB 25 (monofunctional polyether with a number-average molecular weight of 2250g/mol based on ethylene oxide/propylene oxide, OH number 25mg KOH/g, Bayer AG, Leverkusen, DE) are metered in with stirring over the course of 10 minutes. The reaction mixture is heated to 90 ℃ and stirred at this temperature until the theoretical NCO value is reached. After the reaction mixture was cooled to 65 ℃, 62.8g of butanone oxime was added dropwise with stirring over 30 minutes at such a rate that the temperature of the mixture did not exceed 80 ℃. 726.0g of water (T20 ℃) was then added over 30 minutes at 60 ℃. Stirring was carried out at 40 ℃ for 1 hour.

This gives a storage-stable aqueous dispersion of the blocked polyisocyanate having a solids content of 30.0%.

Example 1: comparative example

Baybond^*PU 401 (anionic and nonionic hydrophilic PU dispersions having a solids content of 40% and an average particle size of 100-300nm, Bayer AG, Lerverkusen, DE).

Example 2：

306.0g of polyester PE 170 HN (polyester polyol, OH number 66mg KOH/g, number average molecular weight 1700g/mol, Bayer AG, Lerverkusen, DE), 13.5 g of polyether LB 25 (monofunctional polyether based on ethylene oxide/propylene oxide and having a number average molecular weight 2250g/mol, OH number 25mg KOH/g, Bayer AG, Lerverkusen, DE) and 0.1 g of Desmorapid^*Z (dibutyltin dilaurate, Bayer AG, Lerverkusen, DE) was heated to 65 ℃. A mixture of 91.0 g of isophorone diisocyanate and 71.0 g of acetone is then added at 65 ℃ over 5 minutes, and the mixture is stirred under reflux until the theoretical NCO value is reached. The prepolymer prepared is dissolved in 353.2 g of acetone at 50 ℃ and a solution of 12.4 g of hydrazine hydrate and 40.5 g of water is metered in over 10 minutes. In thatAfter the addition of 17.7 g of diaminosulphonate over 5 minutes, stirring was continued for 15 minutes and dispersion was effected by adding 584.9 g of water over 10 minutes. The solvent was subsequently removed by distillation under vacuum, giving a storage-stable dispersion having a solids content of 40.0%.

Example 3：

1530.0g of polyester PE 170 (polyester polyol, OH number 66mg KOH/g, number-average molecular weight 1700g/mol, Bayer AG, Lerverkusen, DE), 67.5 g of polyether LB 25 (monofunctional polyether based on ethylene oxide/propylene oxide and having a number-average molecular weight 2250g/mol, OH number 25mg KOH/g, Bayer AG, Lerverkusen, DE) and 0.1 g of Desmorapid^*Z (dibutyltin dilaurate, Bayer AG, Lerverkusen, DE) was heated to 65 ℃. 537.1 grams of Desmodur were then added over 5 minutes at 65 deg.C^*A mixture of W (bis- (4, 4' -isocyanatocyclohexyl) methane, Bayer AG, Lerverkusen, DE) and 355.0 g of acetone is stirred at reflux until the theoretical NCO value is reached. The prepolymer prepared is dissolved in 1766.0 g of acetone at 50 ℃ and a solution of 50.0 g of hydrazine hydrate, 51.0 g of isophoronediamine and 401.3 g of water is metered in over 10 minutes. After addition of 63.3 g of diaminosulphonate over 5 minutes, stirring was continued for 15 minutes and dispersion was effected by addition of 2915.0 g of water over 10 minutes. The solvent was subsequently removed by distillation under vacuum, giving a storage-stable dispersion having a solids content of 40.0%.

Example 4：

1468.8.0g of polyester PE 170 HN (polyester polyol, OH number 66mg KOH/g, number average molecular weight 1700g/mol, Bayer AG, Lerverkusen, DE), 64.8 g of polyether LB 25 (monofunctional polyether based on ethylene oxide/propylene oxide and having a number average molecular weight 2250g/mol, OH number 25mg KOH/g, Bayer AG, Lerverkusen, DE) and 0.1 g of Desmorapid^*Z (dibutyltin dilaurate, Bayer AG, Lerverkusen, DE) was heated to 65 ℃. A mixture of 436.9 g of isophorone diisocyanate and 340.8 g of acetone is then added over a period of 5 minutes at 65 ℃ and stirred at reflux untilTo reach the theoretical NCO value. The prepolymer prepared is dissolved in 1695.4 g of acetone at 50 ℃ and a solution of 55.2 g of hydrazine hydrate, 24.5 g of isophoronediamine and 319.0 g of water is metered in over 10 minutes. After the addition of 60.8 g of diaminosulphonate over 5 minutes, stirring was continued for 15 minutes and dispersion was effected by adding 2714.1 g of water over 10 minutes. The solvent was subsequently removed by distillation under vacuum, giving a storage-stable dispersion having a solids content of 40.0%.

Example 5：

1453.5g of polyester PE 170 HN (polyester polyol, OH number 66mg KOH/g, number average molecular weight 1700g/mol, Bayer AG, Lerverkusen, DE), 64.1 g of polyether LB 25 (monofunctional polyether based on ethylene oxide/propylene oxide and having a number average molecular weight 2250g/mol, OH number 25mg KOH/g, Bayer AG, Lerverkusen, DE) and 0.1 g of Desmorapid^*Z (dibutyltin dilaurate, Bayer AG, Lerverkusen, DE) was heated to 65 ℃. A mixture of 432.3 g of isophorone diisocyanate and 343.9 g of acetone is then added at 65 ℃ over 5 minutes, and stirred under reflux until the theoretical NCO value is reached. The prepolymer prepared is dissolved in 2298.5 g of acetone at 50 ℃ and a solution of 40.6 g of hydrazine hydrate, 48.5 g of isophoronediamine and 421.1 g of water is metered in over 10 minutes. After the addition of 60.1 g of diaminosulphonate over 5 minutes, stirring was continued for 15 minutes and dispersion was effected by adding 2608.4 g of water over 10 minutes. The solvent was subsequently removed by distillation under vacuum, giving a storage-stable dispersion having a solids content of 40.0%.

Example 6：

1499.4g of polyester PE 170 HN (polyester polyol, OH number 66mg KOH/g, number average molecular weight 1700g/mol, Bayer AG, Lerverkusen, DE), 66.2 g of polyether LB 25 (monofunctional polyether based on ethylene oxide/propylene oxide and having a number average molecular weight 2250g/mol, OH number 25mg KOH/g, Bayer AG, Lerverkusen, DE) and 0.1 g of Desmorapid^*Z (dibutyltin dilaurate, Bayer AG, Lerverkusen, DE) was heated to 65 deg.CDEG C. A mixture of 446.0 g of isophorone diisocyanate and 355.0 g of acetone is then added over 5 minutes at 65 ℃ and stirred under reflux until the theoretical NCO value (determined by the Near Infrared (NIR) spectral streamline (inline)) is reached. The prepolymer prepared is dissolved in 1766.0 g of acetone at 50 ℃ and a solution of 49.0 g of hydrazine hydrate, 50.0 g of isophoronediamine and 443.0 g of water is metered in over 10 minutes. After addition of 62 g of diaminosulphonate over 5 minutes, stirring was continued for 15 minutes and dispersion was effected by adding 2686.1 g of water over 90 minutes. The subsequent dispersing step, which was carried out analogously under vacuum by distilling off the solvent, gave a storage-stable dispersion having a solids content of 40.0%.

Example 7：

342.0g of poly-THF 2000 (polyether based on tetrahydrofuran, OH number 56mg KOH/g, number average molecular weight 2000g/mol), 16.7 g of polyether LB 25 (monofunctional polyether based on ethylene oxide/propylene oxide, number average molecular weight 2250g/mol, OH number 25mg KOH/g, Bayer AG, Lerverkusen, DE) and 0.1 g of Desmorapid^*Z (dibutyltin dilaurate, Bayer AG, Lerverkusen, DE) was heated to 65 ℃. A mixture of 86.5 g of isophorone diisocyanate and 67.5 g of acetone is then added over 5 minutes at 65 ℃ and the mixture is stirred under reflux until the theoretical NCO value is reached. The prepolymer prepared is dissolved in 335.5 g of acetone at 50 ℃ and a solution of 9.2 g of hydrazine hydrate, 9.4g of isophoronediamine and 73.7 g of water is metered in over 10 minutes. After the addition of 15.0 g of diaminosulphonate over 5 minutes, stirring was continued for 15 minutes and dispersion was effected by adding 615.4 g of water over 10 minutes. The solvent was subsequently removed by distillation under vacuum, giving a storage-stable dispersion having a solids content of 40.0%.

Example 8: comparative example

Aqueous polyurethane dispersions were prepared by the prepolymer mixing method according to DE-A3238169, example 2. Chain extension was again performed using hydrazine hydrate.

Example 9: comparative example

According to US-a 5137967, example 1, an aqueous polyurethane dispersion prepared by a prepolymer mixing process and chain extended using hydrazine hydrate.

Application examples：

Table 1 details the sizing compositions. The composition was prepared as follows: half of the water indicated is added to a mixing vessel and stirred, followed by the addition of the PU dispersions of the invention, the film-forming resins, the crosslinker dispersions and the lubricant (Breox)^*50-A140, BP-Chemicals, GB). The pH was then adjusted to 5-7 using acetic acid and the hydrolyzate of 3-aminopropyltriethoxysilane (A1100, UCC, New York, USA) prepared as described in the specification was added as an aqueous coupling agent solution. Stirring for a further 15 minutes, the sizing is ready for use.

The sizing is then applied to the glass fibers, optionally after adjusting the pH to 5-7. The sized glass fibers are then chopped and dried.

	Sizing 1 comparison	Sizing 2	Sizing 3	Sizing 4	Sizing 5
						Aqueous PU Dispersion Cross-linker Dispersion coupling agent Total Lubricant Water yellowing index [ YI]*	42.0kg11.5kg of example 13.5kg0.6kg0.4kg42.0kg100.0kg61	42.0kg11.5kg of example 23.5kg0.6kg0.4kg42.0kg100.0kg53	42.0kg11.5kg of example 33.5kg0.6kg0.4kg42.0kg100.0kg55	42.0kg11.5kg of example 43.5kg0.6kg0.4kg42.0kg100.0kg53	42.0kg11.5kg of example 53.5kg0.6kg0.4kg42.0kg100.0kg51

Chopped, dried glass fibers prepared by corresponding sizing

	Glue 6	Sizing 7	Sizing 8**Comparison of	Applying 9**Comparison of
					Aqueous PU Dispersion Cross-linker Dispersion coupling agent Total Lubricant Water yellowing index [ YI]*	42.0kg11.5kg of example 63.5kg0.6kg0.4kg42.0kg100.0kg50	42.0kg11.5kg of example 73.5kg0.6kg0.4kg42.0kg100.0kg56	42.0kg11.5kg of example 83.5kg0.6kg0.4kg42.0kg100.0kg63	42.0kg11.5kg of example 93.5kg0.6kg0.4kg42.0kg100.0kg67

Chopped, dried glass fibers prepared by corresponding sizing

In the preparation of the sizing, coupling agent a1100 was used directly; omitting the preparation of the hydrolysate

The yellowness index, which is a measure of the yellowing of sized glass fibers, indicates that glass fibers sized with the sizing composition of the present invention exhibit significantly less thermally induced yellowing than glass fibers obtained with prior art sizing compositions.

Although the invention has been described in detail in the foregoing for the purpose of illustration, it is to be understood that such detail is solely for that purpose and that variations can be made therein by those skilled in the art without departing from the scope of the invention except as it may be limited by the claims.

Claims (19)

1. A sizing composition comprising

I) One or more polyurethane-polyurea dispersions (PU dispersions);

II) optionally further comprising a film-forming resin; and

III) optionally a cross-linking agent;

IV) auxiliaries and additives;

characterized in that the PU dispersions in I) are obtained by:

A) the following were first reacted to prepare an NCO-containing polyurethane prepolymer:

A1) polyisocyanates and

A2) a polymer polyol and/or polyamine having a number average molecular weight of 400-8000g/mol,

A3) optionally low molecular weight compounds having a number average molecular weight of 17 to 400g/mol, selected from the group consisting of mono-and polyols, mono-and polyamines and aminoalcohols,

A4) isocyanate-reactive ionic or potentially ionic hydrophilic compounds and/or

A5) Isocyanate-reactive nonionic hydrophilic compounds

A6) Optionally in the presence of an inert solvent,

with the proviso that none of the components A1) -A5) contain a primary or secondary amine group,

B) dissolving the prepolymer obtained in step A) in an aliphatic ketone or, if the preparation has been carried out in an inert solvent, diluting the prepolymer solution, optionally also adding an aliphatic ketone, and

C) reacting the remaining free NCO groups of the prepolymer with a chain extender comprising:

C1) hydrazine and/or hydrazine hydrate and

C2) optionally compounds according to the definition of A2), A3), A4) and/or A5), with the proviso that

C2) component compounds contain primary and/or secondary amine groups,

the total amount of C1) and C2) is such that the chain growth reaches a calculated degree of 40-200%, and

c1) and C2) are such that at least 40% of the free isocyanate groups are blocked and/or extended by the component C1) with amino groups.

2. The sizing composition of claim 1, wherein the PU dispersion is prepared in step B) and optionally step a) using acetone or butanone as a solvent.

3. The sizing composition of claim 1, wherein the PU dispersions in steps A) to C) contain from 8 to 27% by weight of component A1), from 65 to 85% by weight of component A2), from 0 to 8% by weight of component A3), from 0 to 10% by weight of component A4), from 0 to 15% by weight of component A5), from 1.0 to 2.5% by weight of C1) (based on pure hydrazine, N)₂H₄) And 0 to 8 weight percent% C2), the sum of A4) and A5) being from 0.1 to 25% by weight, the sum of the components adding up to 100% by weight.

4. The sizing composition of claim 1, wherein the PU dispersion is prepared in an amount such that the amounts of C1) and C2) are calculated to a degree that the chain growth is 101-150%.

5. A molded article and/or coating comprising the sizing composition of claim 1 and one or more additives selected from the group consisting of: coupling agents, lubricants, antistatic agents, dyes, pigments, flow aids, light stabilizers, anti-aging agents, UV absorbers, and combinations thereof.

6. A substrate coated with a coating obtained using the sizing composition of claim 1.

7. Glass fibers comprising the sizing composition of claim 1 coated on glass fibers.

8. The glass fiber of claim 7, wherein the sizing composition is applied to the glass filaments drawn from the spinneret at high speed immediately after the filaments are cured.

9. The glass fiber of claim 7, wherein the sizing composition is applied to the glass filaments in a dip tank after the spinning operation.

10. The sizing composition of claim 1, further comprising one or more additives selected from the group consisting of: coupling agents, lubricants, antistatic agents, dyes, pigments, flow aids, light stabilizers, anti-aging agents, UV absorbers, and combinations thereof.

11. The sizing composition of claim 2, wherein the PU dispersions in steps A) to C) contain from 8 to 27% by weight of component A1), from 65 to 85% by weight of component A2), from 0 to 8% by weight of component A2Component A3), from 0 to 10% by weight of component A4), from 0 to 15% by weight of component A5), from 1.0 to 2.5% by weight of C1) (based on pure hydrazine, N₂H₄) 0 to 8% by weight of C2), the sum of A4) and A5) being 0.1 to 25% by weight, the sum of the components adding up to 100% by weight.

12. A substrate coated with a coating obtained using the sizing composition of claim 2.

13. Glass fibers comprising the sizing composition of claim 2 coated on glass fibers.

14. The glass fiber of claim 13, wherein the sizing composition is applied to the glass filaments drawn from the spinneret at high speed immediately after the filaments are cured.

15. The glass fiber of claim 13, wherein the sizing composition is applied to the glass filaments in a dip tank after the spinning operation.

16. A substrate coated with a coating obtained using the sizing composition of claim 3.

17. Glass fibers comprising the sizing composition of claim 3 coated on glass fibers.

18. The glass fiber of claim 17, wherein the sizing composition is applied to the glass filaments drawn from the spinneret at high speed immediately after the filaments are cured.

19. The glass fiber of claim 17, wherein the sizing composition is applied to the glass filaments in a dip tank after the spinning operation.