NO774510L - PROCEDURE FOR REDUCING THE VISCOSITY OF POLYESTER AND POLYETHER POLYOLS. - Google Patents

Description

Polyglycol compounds, e.g. polyoxyalkylene ether polyols, polyester polyols and polytetramethylene glycols, hereinafter called polyols for the sake of convenience, are usually used in the production of urethane polymers. These polyols are reacted with polyisocyanates in the presence of catalysts and other materials to produce urethane polymers which may be in the form of elastomers, sealants , sealing compounds, coating agents, flexible or rigid foams and the like. These polyols can in and of themselves, depending on the nature of the starting material and the molecular weight used, have extremely high viscosities. In addition, when producing certain types of urethane polymers, the polyols may have added inorganic fillers or pigments that contribute to the system's high viscosities. In order for these polyols to be used for the production of urethanes, it is desirable to reduce the viscosities to such a level that handling the solutions is made easier.

The prior art teaches that organic titanate compounds can be effective viscosity-reducing agents when added to polymeric systems using inorganic fillers. However, there is no teaching that these titanate compounds can effectively reduce the viscosity of the polyglycol compounds themselves.

It has been discovered that the addition of small amounts of certain organic titanium compounds to polyols drastically reduces the viscosity of the mixture which allows rapid leveling and easier processing of these polyols after reaction with polyisocyanates or even before reaction with polyisocyanates.

The method, for reducing the viscosity of polyester and. polyether polyols involves the addition of an effective amount of an organotitanium compound to the polyols. The organic titanium compounds that can be used in carrying out the invention can be broadly predicted to be based on tetravalent titanium and have the following structure: Ti(OR)4

where R is a radical selected from the group consisting of an aliphatic radical with 1-18 carbon atoms, an alicyclic radical with between 1 and 3 rings, 5 or 6 carbon atoms per ring, and between 5 and 18 carbon atoms per molecule, an aromatic radical which has

between 1 and 3 rings and between 6 and 18 carbon atoms per molecule, and an acyl radical having between 2 and 18 carbon atoms. Very small amounts of an organotitanium compound have been found to cause pronounced lowering of polyol viscosity, and as little as 0.1% has been shown to reduce viscosity by as much as 30%. Higher concentrations of titanium compound still have a further notable influence, but the values tend to to even out. It is included that the amount of organic titanium compound added to the polyol can vary from 0.01% to approx. 20% by weight of the amount of polyol. The addition of these organic titanium compounds has no notable influence on the rate of cure of the polyols when reacted with polyisocyanates. In fact, it turns out that the addition of organic titanium compounds in the presence of a catalyst, e.g. phenyl mercuric acetate, has a synergistic effect in reducing the viscosity of the polyol mixture. Therefore, the present invention relates to the addition of the amount of the organic titanium compound which varies from 0.01 to approx. 20% by weight based on the polyol concentration, for reducing the viscosity of the polyol whether or not the polyol contains further inorganic fillers or pigments.

The polyols used in accordance with the invention include those polyols which are produced by condensation

■ of monomeric units, e.g. ethylene oxide, propylene oxide, the isomeric butyl oxides, styrene oxide and mixtures thereof with active hydrogen compounds, e.g. ethylene glycol, propylene glycol, water, dipropylene glycol, diethylene glycol, 1,2-butahdiol, 1,3-butanediol, 1,4-butanediol, bexantriol, glycerol, trimethylolpropane, trimethylol-ethane, hydroquinone, pentaerythritol, æ-methylglucoside, sorbitol, sucrose, - ethylenediamine, diethylenetriamine, toluenediamine, aniline,

methylaniline, piperazine, triisopropanolamine and bisphenol A, whereby these polyols have molecular weights that vary from approx. 100 to approx. 26,000.

Included are the polyols which are characterized in that they are essentially hydroxyl-terminated polyether polyols which have the general formula

where R is an alkylene radical, and n is an integer which in a preferred embodiment is sufficiently large that the compound as a whole has a molecular weight of from approx. 100 to approx. 26,000. These will include polyoxyethylene glycol, polyoxypropylene glycol, polyoxybutylene glycol and polytetramethylene glycol. Other typical polyols include block copolymers, e.g. combinations of polyoxypropylene and polyoxyethylene glycols, more specifically those having the general formula where n and m together are sufficient to give the desired minimum molecular weight, i.e. about. 100. Also included are block copolymers of poly-1,2- and 2,3-oxybutylene and polyoxyethylene glycols and poly-1,4-oxybutylene and polyoxypropylene glycols and random copolymers, glycols prepared from mixtures of two or more alkylene peroxides as well as glycols as described above, capped with the ethylene oxide units. The polyols used in accordance with the invention may contain arylene or cycloalkylene radicals together with the alkylene radicals such as e.g. in the condensation products of a polyoxyalkylene ether glycol with α,α'-dibromo-p-xylene in the presence of a catalyst. In such products, the cyclic groups inserted in a polyether chain are preferably phenylene, naphthalene or cyclohexylene radicals or the radicals containing alkyl or alkylene substituents, such as in the tolylene, phenylethylene or xylylene radicals. Also included are the polyols that are produced by reacting hydroxy compounds with acids or anhydrides to form hydroxy-terminated esters. Representative polycarboxylic acids and anhydrides which may be used include oxalic, malonic, succinic, glutaric, adipic, pimeline, suberin, azelain, sebacin, brassyl, tapsia, maleic, fumaric, glutacone-, a-hydromucori-, ^-hydromucon-, a-butyl-a-ethyl-glutar-, a-fl-diethylamber-, isophthal-, terephthal-, hemimellite- and.

suitable polyhydric alcohol including both aliphatic and aromatic can be used, e.g. ethylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, tetraethylene glycol, trimethylene glycol, 1.2-propylene glycol, 1,4-tetramethylene glycol, 1,2-butylene glycol, 1.3-butanediol, 1,4-butanediol, 1,3-pentanediol, 1,6-hexanediol , 1,7-heptanediol, glycerol, 1,1,1-trimethylolpropane, 1,1,1-trimethylolethane, hexane-1,2,6-triol, neopentyl glycol, dibromopentyl glycol, 1,lo-decanediol and 2 ,2-bis(4-hydroxycyclohexyl)propane.

The fillers or inorganic pigments that are occasionally used as additives to the polyols are conventional materials and are generally inert. Typical examples of fillers that can be used in polyol products include attapulgite, kaolin, talc, bentonite, halloysite, aluminum silicate, calcium silicate, magnesium trisilicate, zinc oxide, barium sulfate, titanium dioxide, calcium carbonate, iron oxide and the like. Mixtures of these and other fillers can also be used.

The amount of filler used can be varied over wide areas and is certainly dependent on the special properties and characteristics desired in the final product. In general, fill-. the substance is added in amounts of between 10 and 150% by weight of the polyol component. '

Examples of suitable organic polyisocyanates include such aliphatic diisocyanates as hexamethylene diisocyanate, cyclohexyl-2,4-isocyanate, 4,4-methylene-bis-cyclohexyl isocyanate. Included in the aromatic polyisocyanates are 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, mixtures of 2,4- and 2,6-toluene diisocyanate, 4,4'-methylene bis-phenyl isocyanate, 1,5-naphthalene diisocyanate, 4,4',4"-triphenylmethane triisocyanate and polyalkylene polyaryl polyisocyanate.

The organotitanium compounds that can be used in carrying out the invention include tetramethyl titanate, tetraethyl titanate, . tetraallyl titanate, tetrapropyl titanate, tetraisopropyl titanate, tetrabutyl titanate, tetracyclopentyl titanate, tetrahexyl titanate, tetracyclohexyl titanate, tetrabenzyl titanate, tetraoctyl titanate, tetraethylhexyl titanate, tetranonyl titanate, tetradecyl titanate and tetraoleyl titanate.

Mixed alkyl titanate compounds would include trimethylbutyl titanate, dimethyl dibutyl titanate, triethylbutyl titanate, propyl tributyl titanate, ethyl tricyclohexyl titanate, diisopropyl dioctadecyl titanate, dibutyl dioctadecyl titanate and isopropyl triisostearoyl titanate.

Included among the aromatic titanates is methyl triphenyl titanate. t,.ethrap enyl titanate (o- and m-tetramethylphenyl titanate and 1- and 2-tetranaphthyl titanate.

The following examples are provided for further reference. illustrate the invention. In these examples, the polyols and additives designated by the letters A, B, etc. are as follows: Polyol A ér et. sorbitol-propylene oxide adduct with molecular weight approx. 600.

Additive B is tetrabutyl titanate.

Polyester polyol C is a polyester of adipic acid and diethylene glycol with a molecular weight of approx. 2,900.

Polyol D is an adduct of glycerol, tetrachlorophthalic acid-^

anhydride,' propylene oxide with a molecular weight of approx. 600.

Additive E is isopropyltriisostearoyl titanate..

Polyol F is an adduct of glycerol, allyl glycidyl ether and propylene oxide with a molecular weight of approx. 6,500, uncovered with 15% by weight of ethylene oxide, then treated with 20% by weight of acrylonitrile. Polyol G is an ethylenediamine-propylene oxide-ethylene oxide adduct with a molecular weight of approx. 500 and which contains approx. 10% ethylene oxide.

Polyol H is an adduct of trimethylolpropane, propylene oxide, ethylene oxide with a molecular weight of approx. 25,000, containing approx. 19% propylene oxide.

Example 1

The experiments set out below in Table I were carried out by adding the indicated amounts of additive B to 272 grams of polyol A in a lined container and by dispersing

the mixture with a Cowles Dissolver at 2,500 rpm. my. in

60 sec. The samples were degassed at 1-10 mm Hg pressure at ambient temperatures to remove any entrapped air. The viscosities were determined at 26.7°C using a Brookfield

RVF viscometer with a No. 7 spindle at 2.5 rpm. These results

■ tater indicates the polyol viscosity reductions achieved by them. increased additions of additive B.

Example 2

The procedure from example 1 was used in this example. The effect of additive E on the viscosity of polyester polyol C

is shown in table 11 below.

Example 3

Using the method of Example 1, a viscosity reduction was achieved for polyol D using additive E as shown in Table III below.

Example 4

The effect of additive E on the viscosity of polyol' F was determined using the method set forth in Example 1. A substantial reduction in viscosity was obtained; as shown in Table IV below.

Example 5

Additive B was added to polyol G and the viscosity was determined using the method of Example 1. The reduced viscosity is shown in Table V below.

Example 6

Additive E was added to polyol H and the viscosities were determined using the method of Example 1. The viscosity reduction is shown in Table VI below.

Example 7

A mixture of 272 grams of polyol A was mixed with 128 grams of calcined aluminum silicate, 0.8 grams of phenyl mercuric acetate and 24.4 grams of toluene diisocyanate and 1% by weight of additive B based on the weight of the polyol using a Cowles Dissolver at 2500 rpm for 60 sec. . After degassing, the viscosity was measured using a Brookfield RVF viscometer at 2 minute intervals for 25 minutes at 25.6°C. An identical mixture without the titanate compound was prepared in the same manner, and. the viscosity was determined at 2 minute intervals for 25 minutes at 25.6°C. Plotting the viscosities against time revealed that both samples increased in viscosity at the same rate, indicating that the titanate compound does not appreciably influence the cure rate.

Claims (7)

1. Process for reducing the viscosity of "polyester and polyether polyols by adding an effective amount of an organic titanate having the formula where R is a radical selected from the group consisting of an aliphatic radical with 1-18 carbon atoms, an alicyclic radical with between 1 and 3 rings, 5 or 6 carbon atoms per ring, and between 5 and 18 carbon atoms per molecule, an aromatic radical having between 1 and 3 rings and between 6 and 18 carbon atoms. per molecule, and an acyl radical having between 2 and 18 carbon atoms. 2. Procedure as stated in claim 1, characterized in that tetraisopropyl titanate is used as organic titanate. 3. Procedure as stated in claim 1, characterized in that tetrabutyl titanate is used as the organic titanate. 4. Procedure as stated in claim 1, characterized in that isopropyltriisostearoyl titanate is used as organic titanate. 5. Procedure as stated in claim 1, characterized in that an amount of organic titanate is used of from 0.01 to 20% by weight, calculated on the polyol. 6. Procedure as specified in claim 1, characterized in that it. organic titanates are used in an amount of from 0.1 to 10% by weight, calculated on the polyol. 7. Procedure as stated in claim 1, characterized in that the organic titanate is used in an amount of from 0.5 to 5% by weight, calculated on the polyol.