DE1495975A1 - Process for the production of polyester-modified polysiloxanes - Google Patents

Description

Process for the preparation of polyester-modified polysiloxanes Die Modification of polysiloxanes by reaction with higher molecular organic Hydroxy 1 compounds are known. Thus, polyether-modified ones are used to a considerable extent Polysiloxanes produced and z. B. used as a paint leveling agent.

The present invention relates to a method for producing polyester-modified polysiloxanes and is characterized in that one is liquid Organopolysiloxanes, which are reactive towards organic hydroxyl compounds Contain groups with below 100 C, preferably below 50 ° C, liquid polyesters ; which contain so many free hydroxyl groups that the hydroxyl number is at least 20 amounts, implemented in per se known tracks.

The polyester-modified polysiloxanes produced according to the invention are suitable as lubricants, e.g. for treating glass fibers, and as paint flow agents.

Siloxanes modified with polyesters are already known.

However, these differ from those produced according to the invention Compounds by being derived from monomeric silanes or resinous polysiloxanes and resinous, which only have a relatively low hydroxyl group content Connections are derived. The compounds obtained according to the invention are however, made from liquid organopolysiloxanes and those polyesters that are liquid to viscous at Zirnmer temperature without the use of solvents or represent solid bodies which, at temperatures below 1000C, preferably below 500C, melt into free flowing liquids and have a hydroxyl number of at least 20. In your method according to the invention, preferably The polysiloxanes used also have a statistical uniform distribution at least approximate polymer distribution and thus also a regulated distribution reactive groups.

As in the context of the process according to the invention reactive groups in the organopolysiloxane are used, for. B. the units-Si X or where R denotes a hydrocarbon radical or a hydrogen atom and X denotes a hydrogen atom or a halogen atom, preferably chlorine, or the group -OSO3H, OR '(lt' = lower alkyl radical) M-halogen (M = divalent hydrocarbon radical, preferably alkylene, e.g .: -CH2-, - (CH2) 3-, - (CH2) 4-), M- COOR, M-CN (where M is in particular (1cr radical - (CH2) 2-) or is.

The organopolysiloxanes contain an average of mi mindostons one, preferably 1 to 10, especially 2 to 5, reactive groups, Polysiloxanes with an equilibration or telomerizate i on reactions ensured a uniform, reproducible distribution of the reactive Groups. I) The organopolysiloxanes have a preferred average molecular weight from about 300-5000, especially 500-3000. In average organopolysiloxane molecule are preferably 0 - 8, especially 0 - 3 trifunctional Siliciunatone, i.e. solelle, which are linked to three sanitary atoms. As organo groups in the polysiloxam molecule serve alkyl and aryl radicals. However, organopolysiloxanes with a predominantly, in particular less than 90% or exclusive proportion of methyl groups than organic groups bonded to the Siliciur @. Other genetically with the methyl radical Preferred hydrocarbon groups present are the ethyl, vinyl and phenyl radicals.

The organopolysiloxanes serving as starting materials with reactive endgraps can be z. B. expressed by the following formula: Rx1SiOyX4- (x + 2y) I In this formula: R1 = monovalent hydrocarbon radical which can be the same or different within the polymer molecule; x = 1.5 to 2.1, preferably 1.85 to 2.0; y = 0.9 to 1.3, preferably 0.95 to 1.15; 4> (x + 2y)> 2. If X is a halogen atom, preferably chlorine, it is preferably a part, e.g. B. 5 to 40% of the halogen atoms replaced by 1/2 SO4. The production of such connections is z. As described in French patents 1,267,315, 1,269,110 and 1,269,111. The compounds are characterized by a particularly good poly-egg distribution that comes close to statistical equilibrium. Examples of such siloxanes are: where n = 2 to 100, preferably 5 to 30, and R1 and X have the meaning given above: where n, R1 and X have the meanings given above and m = 1 to 20, preferably 2 to 10; where R and X have the meaning given above and a = 1 to 20, preferably 3 to 10; b = 1 to 20, preferably 1 to 5; where R1, X, a and b have the meaning given above.

Some of the radicals X in the compounds of Fornel II - V can also be replaced by R3Si residues. However, per average molecule should be at least a reactive residue X is retained.

The polyesters used as reactants are z. B. commercial Polyester, such as those used for the production of polyurethane paints or elastomers or foams Find use. Acid components can be, for. B. adipic acid, sebacic acid or phthalic acid, alcohol components ethylene glycol, ethylene diglycol, propylene glycol, Propylene diglycol, butylene glycol or glycols with the addition of triols such as. 13th Be glycerin. Also other dicarboxylic acids and glycols with secondary hydroxyl groups can be used. The polyesters are preferably linear or only weak branched structure and hydroxyl numbers from 20 to 250, particularly preferably from 30 to 90. Another useful polyester is ricin oil.

Other polyesters useful for the reaction are obtained by reacting carboxylic acid anhydrides with alkylene oxides and alkanols or glycols.

The polyesters can before the reaction according to the invention with the polysiloxanes can still be modified by the addition of ethylene or propylene oxide. polyester with secondary hydroxyl groups give particularly hydrolysis-stable modified organopolysiloxanes.

It can also be part of the hydroxyl groups of the polyester with trialkylsilyl groups blocked or reacted with alkyl or aryl isocyanates, so that only an hydroxyl group remains in polyester molecule.

Polysiloxane and polyester can be reacted in such proportions be that the reactive groups in the polysiloxane equivalent amounts of hydroxyl groups be available. When implementing polyfunctional polysiloxanes or polyesters However, the implementation can turn out to be extremely high molecular weight and difficult to process Products. In many cases, it is then advisable to use only some of the hydroxyl groups, z. BS up to 1.5 hydroxyl groups per average molecule, to react with the Bring polysiloxane. In these cases, the polyester is used in excess at.

In addition to the polyesters carrying CH groups, monovalent organic hydroxyl compounds, preferably alkanols or the addition trace; ever of ethylene and / or propylene oxide to such alkanols with de @@@ active siloxane realize. These connections will be in the resulting Block polymer molecule built-in. They serve as chain stoppers.

Preferred monovalent hydroxyl compounds are the attachment products of ethylene and / or propylene oxide to lower alkynols.

The molecular weight should be between 300 and 2000.

Linear block polymers arise z. B. from a polysiloxane with 2 reactive end groups, a linear polyester with terminal hydroxyl groups and a monovalent hydroxy compound, e.g. 13. In a quantitative ratio of full 2: 1: 2 Ltol.

Such compounds can be represented by the following average polymer formula: Here, R1 and n have the meanings already given. R2 is a monovalent organic radical, e.g. B. an alkyl radical or the radical alkyl where v = 2 - 3. z is an integer, preferably between 5 and 50. M is the oxyethylene, oxypropylene or oxybutylene radical. Q is a divalent hydrocarbon radical such as e.g. B. the - (CH2) x radical, where x = 1-10, preferably 4-8, or the phenyl radical. y is chosen so that # hO has a hydroxyl number of about 20-250.

This results in z. B. the following average formula The reaction of polysiloxane and polyester is expediently carried out in inert solvents, preferably in solvents which can also be used for azeotropic drying of the polyesters. Such solvents are e.g. 13. methylene chloride, benzene, toluene. In addition, the conditions of the conversion are to be adapted to the nature of the reactive groups of the siloxane. If the reactive group is a halogen, acyloxy or a sulphate radical, it is expedient to reduce the acid liberated during the reaction by adding ammonia, amines or other known acid scavengers, such as. 13. Is described in French patent specification 1,269,111 to intercept. The reaction temperature should be in the range from 20 to 100.degree.

If the reactive group is a hydrogen atom bonded to silicon, it is reacted in the presence of alkaline catalysts or hexachloroplatinic acid.

If the reactive group is an alkoxy group, the reaction can be carried out in the presence of acidic catalysts, such as. B. trifluoroacetic acid, perform, thereby it is advisable to remove the liberated alcohol azeotropically.

The polysiloxanes, which as reactive groups are the -M-CH and the -MCOOR group are shown by known processes, preferably in the presence of acidic catalysts implemented with the polyester.

If the reactive group of the polysiloxane is the -N-halogen group, then so it is advisable to use the sodium derivatives of the polyester as reactants.

The siloxane-modified polyester produced according to the invention are viscous to viscous liquids. In rare cases it seems unnecessary to win them in rei @@@ form, because their application also in fora their solutions can be done. The method according to the invention is illustrated by the following examples to be explained in more detail: Example 1 61.36 of a polysiloxane of the general formula IV, where R '= CH3; a = G, 17; b = 3; X = 75 to C1, 25% 1/2 SO4 is dissolved in 700 ml of benzene with 300 g of azeotropically dried polyester implemented from adipic acid and ethylene diglycol (hydroxyl number 40). In doing so, 700C passed through the reaction mixture. The benzene solution is filtered and then narrowed down. There remain 350 g of a viscous liquid that 0.5% ethanolamine is added to improve storage stability.

Example 2 54.1 g of a siloxane of formula 11, in which R1 = CH3, n = 13.6 and X = 80 @ Cl and 20 @ 1, '2 SO are calculated using 760 nl Methylene chloride unset 300 g of the polyester mentioned in Example 1, indene at 350C NH3 is passed through the reaction mixture.

Claims (1)

Claims @ 1) Process for the production of polyester-modified Polysiloxanes, characterized in that one liquid organopolysiloxanes, the opposite organic hydroxyl compounds contain reactive groups, with below 100 ° C, preferably 50 C, liquid Ik> y esters, the so many free hydroxyl groups contain that the hydroxyl number is at least 20, in a manner known per se wnsett. 2) Method according to claim 1, characterized in that one is a Polysiloxane with a molecular weight in the range from 500 to 3000 and 1 to 5 reactive Groups in the average molecule with a polyester with a hydroxyl number in the range from 30 to 90. 3) Method according to claim 1 or 2, characterized in that the polysiloxanes are compounds of the general formula (n = 5-30; R1 is a monovalent hydrocarbon radical, preferably the methyl radical; X = halogen, preferably chlorine, some of the halogen radicals can be replaced by SO radicals), L) method according to claim 1 or 2, characterized in that compounds of the general formula are used as polysiloxanes (R1 and X meaning given above; a = 2 - 10; b = 1 - 8) is used. 5) Method according to one of the preceding claims, characterized in that da # @an on average 1 to 1.5 hydroxyl groups in the average polyester molecule Reacts with polysiloxane. 6) Method according to one of the preceding claims, characterized in that that the reaction is carried out in the presence of an inert solvent. 7) Method according to one of the preceding claims, characterized in that that, together with the hydroxyl-containing polyesters, they are also monovalent converts organic hydroxyl compounds.