Patent Application
20080075683
491 g of an α, ω-dihydropolydimethylsiloxane having 0.055% by weight of silicon-bonded hydrogen and a water content of 50 weight ppm are mixed with 1001 g of an allyl alcohol ethoxylate/propoxylate of the formula
H2C=CH-CH2-(OCH2CH2)a[OCH2CH (CH3) ]b-OH,
having an a:b ratio=1.0, a water content of 978 weight ppm and an iodine number of 13.7 (the iodine number indicates the amount of iodine, in grams, consumed in the course of the addition onto the aliphatic unsaturation per 100 grams used of material to be investigated), and the mixture is heated to 100° C. and then has metered into it 0.28 g of a 2.7% by weight (based on elemental platinum) solution of a platinum 1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex in an α,ω-divinyldimethylpolysiloxane having a viscosity of 1000 mPa·s at 25° C., a solution of Karstedt's catalyst (the preparation of which is described in U.S. Pat. No. 3,775,452). The temperature of the reaction mixture rises by about 6° C., whereupon the same amount of catalyst is metered in again. The reaction mixture then turns homogeneous. After an hour's reaction time at 100 to 110° C., a sample of the polyether-polysiloxane intermediate is cooled down and found to have a viscosity of 2220 mm2/s at 25° C.
45.5 g of hexamethylene 1,6-diisocyanate (1.0 mol of isocyanate group per mole of HO group in the intermediate) are then metered in at 100° C., and urethane formation is catalyzed with 100 mg of di- n-butyltin dilaurate. After two hours at 100° C., the clear reaction product is cooled down. Its viscosity is about 100 000 mPa·s at 25° C.
40 g of the highly viscous oil are mixed with 60 g of water at 50° C. The product is readily emulsifiable and forms an opalescent microemulsion having a urethane content of 0.14 meq./g.
Example 1 is repeated mutatis mutandis except that for comparison a different batch of the polyether is used, this batch containing 3620 ppm of water from its method of production. In terms of the entire batch, the water content is now 2350 ppm of water instead of 636 ppm.
The reaction with hexamethylene 1,6-diisocyanate is accompanied by severe foaming. After the reaction has ended, a barely stirrable oil is obtained which, after incorporation of 1.5 times the amount of water (40% oil content), does not spontaneously form an emulsion. Prolonged application of high-shearing forces using a Turrax leads to the formation of a cloudy, inhomogeneous mixture.
960 g of the α,ω-dihydropolydimethylsiloxane having a water content of 50 weight ppm from Example 1 are mixed with 536 g of a polyether of the formula
H2C=CH-CH2-(OCH2CH2)10.2-OH,
having a water content of 686 weight ppm, and heated to 100° C. 0.28 g of Karstedt's catalyst solution described in Example 1 is then added, whereupon the temperature of the reaction mixture rises to 19° C. and a clear product is formed. Complete conversion of the silicon-bonded hydrogen is achieved after one hour at 100 to 110° C. The polyether-polysiloxane intermediate has a viscosity of 760 mm2/s at 25° C.
63 g of N-methyldiethanolamine (1.02 mol of HO group per mole of HO group in the polyether) and 178 g of hexamethylene diisocyanate (0.99 mol of isocyanate group per mole of the sum total of HO groups in the intermediate and the N-methyldiethanolamine) are then meteringly added in succession. Urethane formation is catalyzed with 100 mg of di-n-butyltin dilaurate. After the batch has been held at 100° C. for 2 hours it is cooled down and 64 g of acetic acid are added at 70° C. The clear, brownish product has a viscosity of 120 000 mPa·s at 25° C.
40 g of the highly viscous oil are mixed with 60 g of water at 50° C. Gentle stirring produces a microemulsion having a urethane content of 0.39 meq./g and an amine number of 0.12 (the amine number is the number of ml of 1N HCl needed to neutralize 1 g of substance).
1411 g of the allyl alcohol ethoxylate/propoxylate of Example 1 are mixed with 813 g of an α, ω-dihydropolydimethylsiloxane having 0.052% by weight of silicone-bonded hydrogen and heated to 100° C. with thorough stirring. Identical catalysis provides a polyether-polysiloxane intermediate having a viscosity of 2490 mm2 /s at 25° C. after a reaction time of one hour.
At 100° C., 83 g of N,N-bis(3-dimethylaminopropyl)-N-isopropanolamine are stirred in and 92 g of hexamethylene diisocyanate are metered in. The ratio of NCO groups to the sum total of NCO-reactive organic groups is 0.995 or, taking into account the water present therein, just 0.87. A somewhat exothermic reaction is followed by heating to 120° C., at which point 50 mg of dibutyltin laurate are added and the reaction is allowed to proceed for a further 3 hours until isocyanate is no longer detectable in the IR, while the viscosity increases at the same time. The oil, which is very viscous at 25° C., has a basic nitrogen content of 0.42 meq./g.
635 g of the α,ω-dihydropolydimethylsiloxane of Example 3 are reacted with 205 g of a polyether of the formula
H2C=CH-CH2-(OCH2CH2)9.5-OH,
as in Example 2. The polyether-polysiloxane intermediate has an OH concentration of 0.512 meq./g and contains 177 ppm of water.
200 g of this intermediate are mixed with 10.3 g of bis(dimethylaminopropyl)amine and heated to 84° C.; 13.2 g of hexamethylene diisocyanate are metered in. The ratio of NCO groups to the sum total of NCO-reactive organic functions is 0.998 or, if water is included, 0.97.
Complete conversion of the isocyanate groups is achieved in one hour at about 90° C. in a slightly exothermic reaction without further catalysis. The polymer mixture contains 0.49 meq. of basic nitrogen per gram.
32 g of this polymer are neutralized with a solution of 1.04 g of acetic acid in 8 g of diethylene glycol monobutyl ether. A slightly yellowish microemulsion forms spontaneously with 60 g of water after stirring with a spatula.
200 g of the polyether-polysiloxane intermediate prepared in Example 4 (0.512 meq. of OH/g) are admixed with an additional 26.2 g of the polyether used in the synthesis of the intermediate and also with 14.8 g of bis(dimethylaminopropyl)amine and heated to 80° C. The addition of 19.8 g of hexamethylene diisocyanate immediately starts a moderately exothermic reaction, which ends after about 2 hours at 90° C., and isocyanate is no longer detectable. The ratio of NCO to the sum total of NCO-reactive groups (OH, NH) is 0.995 when water is not included and only 0.97 when the water present therein is included.
The highly viscous polymer mixture has a basic nitrogen concentration of 0.60 meq./g.
A microemulsion is produced by neutralizing 32 g of this product with a solution of 1.29 g of acetic acid in 8 g of diethylene glycol monobutyl ether and then adding 60 g of water with stirring.
200 g of the polyether-polysiloxane intermediate prepared in Example 4 (0.512 meq. of OH/g) and just 4.5 g of bis(dimethylaminopropyl)amine are heated to 88° C. without further additions of polyether. The addition of 10.6 g of hexamethylene diisocyanate starts a slightly exothermic reaction. The ratio of NCO groups to the sum total of NCO-reactive organic functions is 0.998 or, having regard to the water present in the reaction mixture, 0.97.
Isocyanate is no longer detectable after 1 hour at 100° C. The highly viscous polymer has a basic nitrogen content of 0.22 meq./g.
A stable microemulsion is obtained by neutralizing 32 g of basic product with a solution of 0.46 g of acetic acid in 8 g of diethylene glycol monobutyl ether and adding 60 g of water with stirring.
Example 2 is repeated mutatis mutandis replacing the N-methyldiethanolamine in stage 2 by 99 g of bis(dimethylaminopropyl)amine. The amount of hexamethylene diisocyanate is reduced to 131 g (0.98 mol of isocyanate per mole of the sum total of isocyanate-reactive OH and NH groups). Following complete conversion of all isocyanate groups, the batch is neutralized with 70 g of acetic acid and diluted with 450 g of diethylene glycol monobutyl ether. At a polymer content of 80%, this solution has a viscosity of 4900 mm2/s at 25° C. and an amine number of 0.47. A total of 60 g of water is stirred a little at a time into 40 g of this solution at room temperature to form a fine emulsion having an amine number of 0.19.
Compared with Example 7, this example utilizes reduced amounts of raw materials which are monofunctional with regard to isocyanate. The polyether is reduced from 536 g to 402 g and the amine from 99 g to 50 g.
Accordingly, the reaction mixture contains 1.06 mol of isocyanate-reactive groups, which reduces the amount of hexamethylene diisocyanate to 87 g. Neutralization is effected with 35 g of acetic acid. Diluting with 384 g of diethyleneglycol monobutyl ether gives a clear 80% amino PUR silicone polyether solution of 5100 mm2/s (25° C.), which has an amine number of 0.28. This solution is emulsified similarly to Example 7. The fine emulsion formed has an amine number of 0.113.
960 g of the α, ω-dihydropolydimethylsiloxane of Example 1 are reacted with 125 g of a polyether of the formula
H2C=CH-CH2-(OCH2CH2)3.0-OH
having a water content of 780 weight ppm, as described there. After complete conversion of the silicon-bonded hydrogen, the product is heated at 140° C. under reduced pressure to obtain 1060 g of a clear α,ω-dihydroxysiloxane copolymer. 70 g of bis(dimethylaminopropyl)amine and 74 g of hexamethylene diisocyanate are added thereto in succession at 100° C. After two hours at 100° C., all the NCO groups have reacted, and the batch is neutralized with 49 g of acetic acid and diluted with 313 g of diethylene glycol monobutyl ether for simpler handling. The 80% formulation has a viscosity of 2200 mm2/s (25° C.) and an amine number of 0.35.
The emulsification similarly to Example 7 gives a fine emulsion of amine number 0.14.
1492 g of the polyether polysiloxane intermediate of Example 1 are mixed with 51 g of bis(dimethylamino-propyl)amine and 67 g of hexamethylene diisocyanate at 100° C. The slightly exothermic reaction gives complete conversion of the NCO groups after two hours. Neutralization with 35 g of acetic acid and further dilution with 410 g of diethylene glycol monobutyl ether gives a clear formulation having a viscosity of 7800 mm2/s (25° C.) and an amine number of 0.26.
60 g of water are easily stirred into 40 g of this dilution. The aqueous formulation has an amine number of 0.104.
Eight terry towels (225 g), 8 flat woven cotton cloths (20×160 cm, 50 g) and 8 flat woven blend fiber cloths (15×100 cm, 45 g) at a time are washed twice with 130.0 g of silicone-free fully built washing powder in the full wash cycle at 95° C. Thereafter, the fabrics are rinsed twice more by starting the rinse cycle. To treat the fabrics with the siloxane copolymers of the present invention, one terry towel, one flat woven cotton cloth and one flat woven fiber blend cloth were put together in the washing machine and the first rinse cycle started with completely ion-free water. On starting the third and last rinse cycle, the porthole of the washing machine is opened and the drum is entered with 1.5 l of tap water for a resulting water hardness of 30 German hardness and also 5 g of glacial acetic acid for a pH of 4. Then, 10.16 g of inventive silicone emulsion according to Examples 7-9, corresponding to 1.0% of active silicone, on weight of fiber, are put into the drum in each case and the last rinse cycle is started. After the fabrics have been air dried and conditioned at 23° C. and 60% relative humidity overnight they are subjected to performance tests.
Softness is determined by a jury of testers. The terry towels are numbered from 1 to n. Each tester compares—blind—towel 1 with towel 2. If towel 1 is softer, it is rated 1; if it is harsher, it is rated 0; and if the two towels are rated the same they are both awarded 0.5. Then, towel 1 is compared with 3, 1 with 4, etc., through to the comparison of towel n-1 with n. All the ratings for a towel are added together and reported as the result. The jury shall have three members at least.
In the ironing test, the flat woven cotton and fiber blend cloths are ironed without steam on the cotton setting, while counting the number of times the iron has to pass over a piece of fabric to iron the fabric crease free.
In the rewetting test, a drop of blue completely ion-free water is dripped onto the fabric from a height of 1 cm and the time is taken until the drop has been absorbed to such an extent that the first structures in the fabric become visible in the area which was wetted.
In the skid test, a hot iron on the cotton setting without steam is allowed to glide down the fabric at an angle of 6°. The time needed for a skid of 90 cm is taken.
The results of the performance tests are summarized in Table 1.
Compared with untreated terry towels, softness is appreciably improved by the siloxane copolymers of the present invention without noticeable deterioration in water absorption. The skid tests give significantly better results.
A bleached, unfinished woven PES/CO 65/35 twill fabric having a basis weight of 200 g/m2 (fabric 1) and an unfinished 100% CO cretonne knit having a basis weight of 230 g/m2 (fabric 2) were used for textile finishing. The comparison was again a finish with a 33% standard silicone softener emulsion (microemulsion of an amino−functional polydimethylsiloxane=control), commercially available from Wacker-Chemie GmbH under the trade name of Finish CT 34 E, and also water-padded and dried fabric (=blank test).
The fabric was saturated with the respective liquor, squeezed off to a 70% wet pickup using a two-roll mangle, tented and dried in a Mathis laboratory tenter at 150° C. for two minutes. The fabric was then conditioned at 23° C. and 50% relative humidity for at least 12 hours.
Since the softness of textiles is greatly dependent on the subjective feel of the tester, only the boundary conditions can be standardized and not the assessment itself. To ensure reproducibility nonetheless, the finished samples were assessed and ranked in order with regard to their softness. To this end, 10 testers awarded 1 to n points to n tested samples, n points being awarded to the softest sample and 1 point to the least soft sample. The reported result is accordingly the average value of points scored by each sample.
After finishing, the finished sample was conditioned at 23° C. and 50% relative humidity for eight hours before a droplet of deionized water was placed on the taut fabric surface from a height of 6 cm and the time taken for the droplet of water to be absorbed by the fabric was determined, three minutes being the longest time allowed. Five determinations were carried out and the results averaged.
Table 2 summarizes for some performance examples the results of the fabric finished by means of the padding process.
Compared with the untreated fabrics and the fabrics treated with a standard silicone emulsion, softness and water absorption are appreciably improved by the siloxane copolymers used according to the present invention.
The inventive aqueous dispersions of Preparation Examples 7 and 10 and also their mixture (75% of Example 7+25% of Example 10) were tested for softness and absorbency on tissue paper against the Wacker standard products Finish CT 34 E (=comparison 4) and WETSOFT® CTA (=comparison 3).
To this end, the tissue paper was uniformly coated with 1.7% of the respective active silicone ingredient (0.85% each side) . Application was via a three-roll coater. The emulsion under test is filled into a stock reservoir vessel and taken up by a gravure roll. The gravure roll transfers the emulsion to an application roll, which applies the emulsion uniformly to the paper. The paper moves on the carrier between the application roll and a contact roll. The process is repeated for coating the other side of the paper.
The tissue paper used in the test is a commercially available, highly absorbent and open-pored tissue style, so that the coated papers were virtually free of any differentiation with regard to absorbency.
A number of differently coated tissue papers were compared with each other and with an uncoated paper (blank value) by touching.
A tester compares 2 tissue papers of equal size with each other by handling with the fingers (skin contact), and decides which tissue paper has a softer and more pleasant feel, or whether there is no difference.
The softer paper scores 1 point, the worse paper 0 points, and if there is no tangible difference both papers get 0.5 points.
All coated tissue papers and the blank value are compared with each other according to this procedure.
In the assessment of Table 3, 5 papers coated with different products and the blank value were examined by altogether 4 judges; i.e., the product with the best softness can achieve a maximum of 20 points, while the worst possible score is 0 points.
To determine the water uptake of a coated tissue paper, the so-called droplet test is carried out. To this end, the papers to be tested are clamped taut without creases in a frame (metal lid with tensioning ring), and a drop of water is buretted at a rate of 5 s/drop from a height of 1 cm onto the tissue paper to be tested.
The time is taken until the droplet of water has completely disappeared.
This test is carried out altogether 4 times (2 times per side) in various places of the tissue paper. The average of the 4 measurements is reported. The results are summarized in Table 3.
The two comparative products WR 1100 and CTA were distinctly inferior to the inventive siloxane copolymers of Examples 7 and 10 and their mixture with regard to softness. In the droplet test, i.e., in relation to a tissue paper's water uptake and absorbency, all the products were much of a muchness, but here too the inventive siloxane copolymers tended if anything to have a better water uptake than the comparative examples.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2004 028 322.2 | Jun 2004 | DE | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP05/05952 | 6/2/2005 | WO | 00 | 12/5/2006 |
