CN110818875A - A kind of organosilicon modified polyurethane and its application and preparation method of coated fabric - Google Patents

Abstract

The invention discloses an organosilicon modified polyurethane and its application and a preparation method for its coated fabric. The preparation method comprises the following steps: (a) vacuum drying polyethylene glycol, hydroxysilicone oil and DMBA, and heating and activating 4A molecular sieve (b) adding polyethylene glycol, hydroxysilicone oil, IPDI and acetone to react; (c) adding DMBA and dibutyltin dilaurate, cooling down after the reaction; (d) adding glycidol and acetone, and reducing the temperature of the system to drop, add TEA, stir and neutralize to form salt; (e) rotary steam to purify the modified polyurethane; (f) padding and shaping to obtain a modified polyurethane coated fabric. The organosilicon-modified polyurethane is prepared from the preparation method of an organosilicon-modified polyurethane coated fabric. The silicone-modified polyurethane is used for fabric deepening. The preparation process of the invention is simple and the cost is low, not only can the color depth of the fabric be improved, but also has excellent friction resistance and durability, and is beneficial to prolong the service life of the fabric product.

Description

A kind of organosilicon modified polyurethane and its application and preparation method of coated fabric

technical field

The invention relates to the field of polymer materials, in particular to an organosilicon modified polyurethane and its application and a method for preparing a coated fabric.

Background technique

In recent years, due to the influence of factors such as balanced dye uptake and dye fastness of fiber dyeing, the color depth of fabrics after dyeing has attracted much attention. When fabrics are dyed, the color depth of the fabrics is insufficient due to the low dye uptake rate or low fixation rate. In order to meet the higher and stricter requirements of the market for coated fabrics, the production cost is reduced, and the use of dyes and coatings is reduced. Quantity, need a deepening agent to change the status quo.

Nowadays, silicone-based deepening agents are commonly used, because silicone resins have low refractive index and low surface energy, and have the advantages of good reactivity, adsorption, flexibility, and no pollution. However, when the silicone resin is used as a coating fabric deepening agent, the adhesion to the coating is poor, and the problems of dyeing depth and fastness of the coated fabric cannot be effectively solved.

SUMMARY OF THE INVENTION

Purpose of the invention: In order to overcome the deficiencies in the prior art, the purpose of the present invention is to provide a preparation method of an organosilicon-modified polyurethane coated fabric which has a deepening property and can be cured on the surface of the fabric to improve the washing fastness of the fabric. Another object of the invention is to provide a silicone-modified polyurethane, and another object of the invention is to provide an application of the silicone-modified polyurethane in fabric deepening.

Technical scheme: the preparation method of an organosilicon-modified polyurethane coated fabric according to the present invention comprises the following steps:

a. Put polyethylene glycol, hydroxysilicone oil and 2,2-dimethylolbutyric acid (DMBA) into a vacuum drying oven at 80～90℃ and heat for 12～14h, remove the moisture in the reaction raw materials, and use a vacuum tube type high temperature The sintering furnace heats and activates the 4A molecular sieve at 600-650°C for 4-5 hours, then puts it into acetone to absorb moisture, and treats it for 7-8 days before use;

b. Use oil bath heating and mechanical stirring to build a reaction device, and add polyethylene glycol with a molecular weight of 400 to 1000 and hydroxyl silicone oil with a molecular weight of 400 to 1000, polyethylene glycol and hydroxyl The dripping speed of silicone oil is 1-2 drops/s, n (polyethylene glycol): n (hydroxy silicone oil) = 1-3: 2, stirring speed is 200-300r/min, then add IPDI and acetone, 70-75 Reaction at ℃ for 2～3h, n(IPDI):n(polyethylene glycol + hydroxy silicone oil)=20:9～10;

c. Add chain extender DMBA again, n(IPDI):n(DMBA)=4:1～2, add 2～3 drops of dibutyltin dilaurate catalyst at the same time, stirring speed is 350～400r/min, in After reacting at 70～75℃ for 2～3h, use an ice pack to cool down, and slowly drop to 60～65℃ at a cooling rate of 0.5℃/min;

d. In the end capping stage, add a total volume of 70-80 ml of glycidol and 12-15 mol of solvent acetone, react at 60-65 °C and a stirring speed of 200-300 r/min for 1-1.5 h, and reduce the temperature of the system to 40-45 °C Then, add triethylamine (TEA) with a neutralization degree of 100%, n(IPDI):n(glycidol):n(TEA)=10:1～2:1, stir for 30～50min to form a salt to obtain glycidol End-capped silicone-modified waterborne polyurethane;

e. The synthetic hydroxyl silicone oil modified polyurethane solution is subjected to rotary evaporation to purify the modified polyurethane;

f. The padding time is 3～4min, the rolling ratio is 70～80%, pre-bake at 70～80℃, and then bake at 120～125℃ for 2～3min, set the cloth sample, and obtain the modified polyurethane coating fabric.

Among them, glycidol is prepared by using monochloropropanediol and 1,2-dichloroethane, heating for 1-1.5h to boiling, adding sodium hydroxide in batches, filtering and distilling.

The organosilicon-modified polyurethane prepared in the preparation method of the above-mentioned organosilicon-modified polyurethane-coated fabric has high film-forming property and good adhesion. When preparing the hydroxysilicone oil modified polyurethane, the performance of the synthesized organosilicon modified polyurethane is controlled by controlling the ratio of the molecular weight of the hydroxysilicone oil and the polyethylene glycol to the softness and hardness. While ensuring its film-forming properties, it also maximizes its deepening effect. And the main chain of hydroxy silicone oil is composed of -Si-O-Si- skeleton, methyl groups are connected with silicon atoms to form side groups, and the silicon-oxygen bond in the main chain is large in volume and low in cohesive energy density. This special structure and composition, It can effectively improve the weather resistance, thermal stability and wear resistance of polyurethane.

The application of the above-mentioned organosilicon-modified polyurethane in fabric deepening can increase the color depth of the fabric while combining with the fabric to improve the washing fastness of the fabric.

Treatment principle: In the prepolymerization stage, hydroxy silicone oil is added to synthesize the modified prepolymer, and the silicone is inserted into the polyurethane segment, which effectively reduces the refractive index of the polyurethane. The epoxy group contained in the ring-opening reaction is closely combined with the hydroxyl group on the fabric to form a coating. Due to the presence of organic silicon, the light is irradiated on the surface of the fabric, the reflected light is reduced, the amount of incident light is increased, and the color depth of the fabric surface is increased. And the coating formed by the modified polyurethane on the surface of the fabric can effectively cover the dye on the surface of the fabric and improve the washing fastness and rubbing fastness of the fabric. The existence of the coating also further increases the tensile properties of the fabric. .

Beneficial effect: Compared with the prior art, the present invention has the following remarkable features:

1. In the prepolymerization stage, the silicone segment is inserted into the polyurethane prepolymer. The presence of silicone in the polyurethane segment can effectively reduce the refractive index of the polyurethane. The surface of the fabric is cured to form a film, which is beneficial to increase the color depth of the fabric;

2. The preparation process of the present invention is simple, the cost of using reagents is low, and it is suitable for most processes. It can not only improve the color depth of the fabric, but also has excellent friction resistance and durability, and will not fall off even if it suffers from large friction. It is beneficial to prolong the service life of fabric products.

Description of drawings

Fig. 1 is the organosilicon modified polyurethane deepening principle of the present invention;

Fig. 2 is the infrared spectrogram of the modified polyurethane obtained in Example 4 of the present invention;

Fig. 3 is the emulsion particle size distribution diagram of the modified polyurethane finishing fabric obtained in Example 4 of the present invention.

Detailed ways

The reaction mechanism of silane coupling agent with epoxy group and fabric is as follows:

The deepening principle of silicone-modified polyurethane is shown in Figure 1. The decrease of the reflectivity of the fabric surface reduces the reflected light on the fabric surface, the transmitted light increases, and the color depth of the fabric also increases.

Example 1

(1) Put polyethylene glycol 400 (molecular weight), hydroxysilicone oil 400 (molecular weight) and 2,2-dimethylolbutyric acid (DMBA) into a vacuum drying box and heat at 87°C for 12h to remove the moisture in the reaction raw materials . The 4A molecular sieve was heated at 600 ℃ for 4 hours in a vacuum tube high-temperature sintering furnace for activation, and then put into acetone to absorb water, and it can be used after a week of treatment;

(2) Use oil bath heating and mechanical stirring to build a reaction device, add 0.3 mol of polyethylene glycol and 0.6 mol of hydroxy silicone oil to a three-necked flask with a condenser, and then add 2 mol of IPDI and 10 mol of acetone, 70°C, The reaction was carried out at a stirring speed of 200r/min for 2h, and polyethylene glycol 400 and hydroxysilicone oil 400 were added dropwise using a constant pressure funnel, 2 drops/s;

(3) then add 1mol of DMBA as chain extender, add 2 drops of dibutyltin dilaurate as catalyst simultaneously, react at 70°C and stirring speed 350r/min for 2h and then slowly cool down to 60°C;

(4) 0.2 mol of glycidol was added in the capping stage, and 12 mol of solvent acetone was added at the same time, and the stirring speed of the stirring bar was 280 r/min, and the reaction was carried out at 60° C. for 1.5 h. Then, after the temperature of the system was lowered to 40°C, 1 mol of triethylamine (TEA) was added with a neutralization degree of 100%, and stirred for 50 minutes to form a salt to obtain a silicone oil-terminated silicone-modified water-based polyurethane;

(5) rotating the synthesized hydroxysilicone oil-modified polyurethane solution to remove unreacted substances in the system and solvent acetone, and purify the modified polyurethane;

(6) The fabric was immersed in 30g/L modified polyurethane emulsion for finishing for 3 minutes, then rolled with a rolling ratio of 70%, pre-baked at 70 °C, and then set at 120 °C for 3 minutes to treat the fabric sample to obtain the modified fabric. Polyurethane coated fabric.

Example 2

(1) Put polyethylene glycol 1000, hydroxysilicone oil 1000 and 2,2-dimethylolbutyric acid (DMBA) into a vacuum drying box and heat at 82°C for 14h to remove the moisture in the reaction raw materials. The 4A molecular sieve was heated at 650 ℃ for 5 hours by using a vacuum tube high temperature sintering furnace, and then put into acetone to absorb water, and it can be used after 8 days of treatment;

(2) Use oil bath heating and mechanical stirring to build a reaction device, add 0.45mol of polyethylene glycol and 0.45mol of hydroxy silicone oil to a three-necked flask with a condenser, and then add 2mol of IPDI and 10mol of acetone, 75 ℃, The stirring speed was 300r/min for 3h, and polyethylene glycol 1000 and hydroxysilicone oil 1000 were added dropwise using a constant pressure funnel, 2 drops/s;

(3) then add 0.5mol of DMBA as chain extender, add 3 drops of dibutyltin dilaurate as catalyst simultaneously, react at 75°C and stirring speed 400r/min for 3h and then slowly cool down to 65°C;

(4) Add 0.2 mol of glycidol and 15 mol of solvent acetone at the end-capping stage at the same time. The stirring speed of the stirring bar is 220 r/min, and the reaction is carried out at 65° C. for 1 h. Then, after the temperature of the system was lowered to 45°C, 1 mol of triethylamine (TEA) was added with a neutralization degree of 100%, and stirred for 30 minutes to form a salt to obtain a silicone oil-terminated silicone-modified water-based polyurethane;

(5) rotating the synthesized hydroxysilicone oil-modified polyurethane solution to remove unreacted substances in the system and solvent acetone, and purify the modified polyurethane;

(6) The fabric was immersed in 30g/L modified polyurethane emulsion for finishing for 4min, then rolled and pressed with a rolling ratio of 80%, pre-baked at 80°C, and then set at 120°C for 2 minutes to treat the fabric sample to obtain the modified fabric. Polyurethane coated fabric.

Example 3

(1) Put polyethylene glycol 400, hydroxysilicone oil 400 and 2,2-dimethylolbutyric acid (DMBA) into a vacuum drying box and heat at 85°C for 13h to remove the moisture in the reaction raw materials. The 4A molecular sieve was heated at 625°C for 4.5h and activated in a vacuum tube high-temperature sintering furnace, then put into acetone to absorb moisture, and it can be used after one week of treatment;

(2) Use oil bath heating and mechanical stirring to build a reaction device, add 0.6 mol of polyethylene glycol and 0.4 mol of hydroxy silicone oil to a three-necked flask with a condenser, then add 2 mol of IPDI and 10 mol of acetone, and stir at 72 °C The reaction rate was 250r/min for 2.5h, and polyethylene glycol 400 and hydroxysilicone oil 400 were added dropwise using a constant pressure funnel, 2 drops/s;

(3) then add 1mol of DMBA as chain extender, add 2 drops of dibutyltin dilaurate as catalyst simultaneously, and slowly cool down to 63°C after reacting for 2.5h at 73°C and stirring speed 375r/min;

(4) 0.2 mol of glycidol was added in the capping stage, and 13 mol of solvent acetone was added at the same time, and the stirring speed of the stirring bar was 200 r/min, and the reaction was carried out at 63 ° C for 1 h. Then, after the temperature of the system was lowered to 43° C., 1 mol of triethylamine (TEA) was added with a neutralization degree of 100%, and stirred for 40 minutes to form a salt to obtain a silicone oil-terminated silicone-modified water-based polyurethane;

(5) rotating the synthesized hydroxysilicone oil-modified polyurethane solution to remove unreacted substances in the system and solvent acetone, and purify the modified polyurethane;

(6) The fabric was immersed in 30g/L modified polyurethane emulsion for finishing for 3 minutes, then rolled and pressed with a rolling ratio of 75%, pre-baked at 75 °C, and then treated at a high temperature of 120 °C for 2.5 minutes. Polyurethane coated fabric.

Example 4

(1) Put polyethylene glycol 600, hydroxysilicone oil 600 and 2,2-dimethylolbutyric acid (DMBA) into a vacuum drying box and heat at 80°C for 12h to remove the moisture in the reaction raw materials. The 4A molecular sieve was heated at 610 ℃ for 4 hours by using a vacuum tube high-temperature sintering furnace, and then put into acetone to absorb water, and it can be used after one week of treatment;

(2) Use oil bath heating and mechanical stirring to build a reaction device, add 0.3 mol of polyethylene glycol and 0.6 mol of hydroxy silicone oil to a three-necked flask with a condenser, and then add 2 mol of IPDI and 10 mol of acetone, 71 ℃, The stirring speed is 220r/min and the reaction is carried out for 2h, and polyethylene glycol 600 and hydroxy silicone oil 600 are added dropwise using a constant pressure funnel, 2 drops/s;

(3) then add 1mol of DMBA as chain extender, add 2 drops of dibutyltin dilaurate as catalyst simultaneously, react at 72°C and stirring speed 360r/min for 2h and then slowly cool down to 62°C;

(4) 0.4mol of glycidol was added in the capping stage, and 14mol of solvent acetone was added at the same time, the stirring speed of the stirring bar was 300r/min, and the reaction was carried out at 61°C for 1.5h. Then, after the temperature of the system was lowered to 41 °C, 1 mol of triethylamine (TEA) was added with a neutralization degree of 100%, and stirred for 35 minutes to form a salt to obtain a silicone oil-terminated silicone-modified water-based polyurethane;

(5) rotating the synthesized hydroxysilicone oil-modified polyurethane solution to remove unreacted substances in the system and solvent acetone, and purify the modified polyurethane;

(6) The fabric is immersed in 30g/L modified polyurethane emulsion for finishing for 3 minutes, then rolled and pressed with a rolling ratio of 72%, pre-baked at 73 °C, and then treated at a high temperature of 120 °C for 2 minutes to treat the fabric sample to obtain the modified fabric. Polyurethane coated fabric.

Example 5

(1) Put polyethylene glycol 800, hydroxysilicone oil 400 and 2,2-dimethylolbutyric acid (DMBA) into a vacuum drying box and heat at 90°C for 14h to remove the moisture in the reaction raw materials. The 4A molecular sieve was heated at 640 ℃ for 5 hours by using a vacuum tube high temperature sintering furnace, and then put into acetone to absorb moisture, and it can be used after one week of treatment;

(2) Use oil bath heating and mechanical stirring to build a reaction device, add 0.3 mol of polyethylene glycol and 0.6 mol of hydroxy silicone oil to a three-necked flask with a condenser, and then add 2 mol of IPDI and 12 mol of acetone, 74 ℃, The stirring speed was 280r/min for 2h, and polyethylene glycol 800 and hydroxysilicone oil 400 were added dropwise using a constant pressure funnel, 2 drops/s;

(3) then add 1mol of DMBA as chain extender, add 2 drops of dibutyltin dilaurate as catalyst simultaneously, react at 74°C and stirring speed 390r/min for 3h and then slowly cool down to 64°C;

(4) 0.2 mol of glycidol was added in the capping stage, and 2 mol of solvent acetone was added at the same time, the stirring speed of the stirring bar was 250 r/min, and the reaction was carried out at 64° C. for 1.5 h. Then, after the temperature of the system was lowered to 44° C., 1 mol of triethylamine (TEA) was added with a neutralization degree of 100%, and stirred for 45 minutes to form a salt to obtain a silicone oil-terminated silicone-modified water-based polyurethane;

(5) rotating the synthesized hydroxysilicone oil-modified polyurethane solution to remove unreacted substances in the system and solvent acetone, and purify the modified polyurethane;

(6) The fabric was immersed in 30g/L modified polyurethane emulsion for finishing for 3 minutes, then rolled and pressed with a rolling rate of 78%, pre-baked at 78°C, and then treated at a high temperature of 120°C for 3 minutes to treat the fabric sample to obtain the modified fabric. Polyurethane coated fabric.

The effect of fabric deepening after finishing with different concentrations of finishing liquid in Table 1 Example 4

sample L* a* b* C* h* K/S Deepening rate original fabric 33.11 -1.57 -36.42 36.45 267.53 16.649 - 10g/L finishing 31.97 -1.72 -37.12 37.13 268.89 18.476 10.97% 20g/L finishing 29.79 -1.47 -36.22 37.02 268.17 21.611 29.80% 30g/L finishing 29.91 -1.28 -36.31 36.88 268.3 21.428 28.70% 60g/L finishing 31.4 -1.07 -36.4 36.42 268.32 19.19 15.26%

Among them, L represents the lightness, a represents the range from magenta to green, b represents the range from yellow to blue, and K/S represents the color depth of the fabric.

Examples 1 to 5 are the silicone-modified polyurethanes prepared under the conditions of polyethylene glycol with different molecular weights and polyethylene glycol with different soft segment ratios and hydroxy silicone oil, wherein the performance of the silicone-modified polyurethane prepared in Example 1 Best, its curing performance is the best, it can be completely cured after 5-7s in the oven, and its deepening effect is 0.7-1.2% higher than others under the same dosage. Use infrared spectrum to judge whether the modified polyurethane prepared in Example 4 is successfully synthesized. As shown in Figure 2, there is a stretching vibration absorption peak of Si-O-Si from the hydroxy silicone oil at 790cm ^-1 , indicating that the hydroxy silicone oil is successfully connected. . The prepared organosilicon-modified polyurethane deepening finishing agent can quickly form a film on the surface of the fabric after high temperature setting, and the existence of the polyurethane film can effectively increase the tensile fastness of the fabric. The cured film itself has no color and will not affect the color of the fabric itself. The K/S value of the fabric obtained in Example 4 before and after finishing is 20-30 g/L of hydroxysilicone oil modified polyurethane solution. The measured K/S value is the largest, and the particle size distribution of the solution is uniform, the solution temperature, and the cured film formed on the surface of the fabric after finishing can effectively reduce the reflectivity of incident light on the surface of the fabric, increase the incident light, and deepen the fabric. The rate reaches 10-28%.

Claims (10)

1. a preparation method of organosilicon modified polyurethane coating fabric is characterized in that comprising the following steps: (a) vacuum-drying polyethylene glycol, hydroxy silicone oil and DMBA, heating and activating 4A molecular sieve at 600-650° C., putting it into acetone to absorb moisture, and treating for 7-8 days before use; (b) adding polyethylene glycol and hydroxy silicone oil to a three-necked flask with a condenser, carrying out oil bath and mechanical stirring, then adding IPDI and acetone, and reacting at 70-75° C. for 2-3 hours; (c) Add chain extender DMBA again, add 2-3 drops of dibutyltin dilaurate catalyst at the same time, after stirring and reacting at 70-75 ℃ for 2-3 hours, slowly cool down to 60-65 ℃, and the cooling rate is 0.5 ℃ /min; (d) adding glycidol and acetone, stirring and reacting at 60-65°C for 1-1.5h, lowering the temperature of the system to 40-45°C, adding TEA at a neutralization degree of 100%, stirring for 30-50min to form a salt, and obtaining Glycidyl-terminated silicone-modified waterborne polyurethane; (e) rotary evaporation is carried out by step d obtained solution to purify modified polyurethane; (f) Padding and setting the cloth sample to obtain a modified polyurethane coated fabric. 2. the preparation method of a kind of organosilicon modified polyurethane coating fabric according to claim 1, is characterized in that: in described step (a), the temperature of vacuum drying is 80～90 ℃, and the time is 12～14h, The activation treatment time is 4-5h. 3. the preparation method of a kind of organosilicon modified polyurethane coating fabric according to claim 1, is characterized in that: in described step (b), the molecular weight of polyethylene glycol is 400～1000, and the molecular weight of hydroxy silicone oil is 400-1000, n (polyethylene glycol): n (hydroxy silicone oil) = 1-3: 2, the dropping rate of polyethylene glycol and hydroxy silicone oil is 1-2 drops/s. 4. the preparation method of a kind of organosilicon modified polyurethane coating fabric according to claim 3, is characterized in that: in described step (b), n (IPDI): n (polyethylene glycol+hydroxyl silicone oil) =20:9-10. 5 . The method for preparing a silicone-modified polyurethane coated fabric according to claim 1 , wherein: in the step (b), the stirring speed of the mechanical stirring is 200-300 r/min. 6 . 6. the preparation method of a kind of organosilicon modified polyurethane coating fabric according to claim 1, is characterized in that: in described step (c), stirring speed is 350～400r/min, n(IPDI): n (DMBA)=4:1-2. 7. the preparation method of a kind of organosilicon modified polyurethane coating fabric according to claim 1, is characterized in that: in described step (d), n (IPDI): n (glycidol): n (TEA) =10:1～2:5, the stirring speed of the stirring bar is 200～300r/min, and the total amount of acetone added during the experiment is 12～15mol. 8 . The method for preparing a silicone-modified polyurethane coated fabric according to claim 1 , wherein in the step (f), the padding time is 3 to 4 min, and the rolling ratio is 70 to 80 . %, pre-bake at 70～80℃, then bake at 120～125℃ for 2～3min. 9. The organosilicon-modified polyurethane prepared in the preparation method of the organosilicon-modified polyurethane-coated fabric according to any one of claims 1 to 8. 10. The application of the organosilicon-modified polyurethane of claim 9 in fabric deepening.

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