A kind of silane modified polyester prepolymer and preparation method thereof

Abstract

The present invention relates to a silane-modified polyester prepolymer (IPC classification number: C08G63 / 91), and more particularly to a silane-modified polyester prepolymer and a preparation method thereof. By weight, the raw materials at least comprise: 10 to 100 parts of polyester polyol and 1-80 parts of isocyanate siloxane. The silane-modified polyester prepolymer prepared by the present invention, in addition to being able to impart sufficient adhesion between the adhesive and the hydrophobic cloth, also improves the performance of water washing resistance, avoiding the problems of falling off and cracking during the washing process.

Description

Technical Field

[0001] The invention relates to a silane-modified polyester prepolymer (IPC classification number: C08G63 / 91), in particular to a silane-modified polyester prepolymer and a preparation method thereof. Background Art

[0002] As the demand for reflective fabrics increases, various reflective fabrics, such as reflective hydrophobic fabrics, have emerged to meet the needs of the market. However, the existing reflective hydrophobic fabrics have poor bonding effect, water resistance and wear resistance due to the poor adhesive effect of the adhesive, which makes the produced reflective hydrophobic fabrics also have problems such as easy falling off before and after washing and wear resistance. Silane-modified polyester prepolymers can improve the surface tension of polymers and reduce the surface energy of resins, and are often mixed with other resins to improve the bonding performance and water washing resistance of adhesives. However, there are few patents related to the preparation of silane-modified polyester prepolymers.

[0003] Patent application CN201710770055.4 discloses a method for preparing a silane-modified polyester prepolymer. The silane-modified polyester prepolymer prepared by this preparation method can only be used for aluminum-plastic composite films, and the catalyst used greatly increases the preparation cost.

[0004] The silane-modified polyester prepolymer prepared by the present invention has good wetting and leveling effect when used in adhesives, and can be well dispersed in reflective hydrophobic cloth, so that the quality of the obtained reflective hydrophobic cloth is relatively high. At the same time, the silane-modified polyester prepolymer prepared by the present invention, in addition to being able to impart sufficient adhesion between the adhesive and the hydrophobic cloth, also improves the water-washing resistance, avoiding the problems of falling off and cracking during the washing process. Summary of the invention

[0005] Aiming at the defects that the adhesive selected for the existing reflective cloth is sensitive to water vapor during the compounding process, is not resistant to high and low temperatures, has poor bonding effect, and the quality of the reflective hydrophobic cloth obtained is unstable, the present invention provides a silane-modified polyester prepolymer and a preparation method thereof.

[0006] In order to solve the above problems, the first aspect of the present invention provides a silane-modified polyester prepolymer, wherein the raw materials at least comprise: 10 to 100 parts of polyester polyol and 1 to 80 parts of isocyanate siloxane, in parts by weight.

[0007] In the present invention, the amount of isocyanate siloxane added varies with the molecular weight of the polyester polyol.

[0008] As a preferred solution, the polyester polyol comprises 100 parts and the isocyanate siloxane comprises 15-40 parts.

[0009] As a preferred solution, the polyester polyol is a low-crystalline polyester polyol.

[0010] As a preferred solution, the low-crystalline polyester polyol is a crystalline polyester polyol formed by condensation of a straight-chain dicarboxylic acid and a diol containing side methyl groups.

[0011] As a preferred solution, the straight-chain dicarboxylic acid is one or more of succinic acid, adipic acid, suberic acid, sebacic acid, dodecanedioic acid, and tetradecanedioic acid.

[0012] As a preferred solution, the diol containing side methyl groups is one or more of methyl propylene glycol, neopentyl glycol, 3-methyl-1,5-pentanediol, and trimethylpentanediol.

[0013] As a preferred solution, the number average molecular weight of the polyester polyol is 1800-2200 g / mol.

[0014] As a preferred solution, the number average molecular weight of the polyester polyol is 1900-2100 g / mol.

[0015] As a preferred solution, the number average molecular weight of the polyester polyol is 2000 g / mol.

[0016] As a preferred solution, the polyester polyol is poly(2-methylpropanediol adipate).

[0017] As a preferred solution, the weight ratio of the polyester polyol to the isocyanate siloxane is 20:(3-8).

[0018] As a preferred solution, the isocyanate silane is one or more of 3-isocyanate propyl methyl dimethoxy silane, 3-isocyanate propyl methyl diethoxy silane, 3-isocyanate propyl trimethoxy silane, 3-isocyanate propyl triethoxy silane, and 3-isocyanate propyl triethoxy silane.

[0019] As a preferred solution, the isocyanate silane is 3-isocyanate propylmethyldiethoxysilane.

[0020] The second aspect of the present invention provides a method for preparing a silane-modified polyester prepolymer, the steps of which mainly include:

[0021] (1) adding polyester polyol to a high-position reactor, heating, vacuuming and dehydrating, cooling, and introducing nitrogen;

[0022] (2) adding isocyanate siloxane and reacting for more than 2 hours to obtain a silane-modified polyester prepolymer.

[0023] As a preferred solution, the heating temperature in step (1) is 110-120° C.;

[0024] As a preferred solution, the heating temperature in step (1) is 115°C;

[0025] As a preferred solution, the vacuum degree in step (1) is -0.09 MPa to -0.1 MPa;

[0026] As a preferred solution, the vacuum degree in step (1) is -0.095 MPa;

[0027] As a preferred solution, the step (1) is dehydrating to a water content of less than 500 ppm;

[0028] As a preferred solution, the cooling temperature in step (1) is less than 80°C.

[0029] As a preferred solution, the cooling temperature in step (1) is 40-60°C.

[0030] In the process of the present invention, the reaction temperature is strictly controlled within the range of 110 to 120° C. in step (1) to ensure the smooth progress of the reaction. The movement of the polyester polyol molecules is increased by heating to ensure the reaction rate of the subsequent reaction. At the same time, in step (1), the water in the reaction system is removed from the system by vacuuming, and at the same time, some low-molecular substances in the high-level reactor are also extracted to avoid affecting the smooth progress of the reaction. When dehydration is performed to a water content of less than 500 ppm, the predetermined standard is reached, thereby ensuring the smooth progress of the subsequent reaction and the quality of the final product. At the same time, the reaction system is protected by nitrogen, which can reduce the impact of the external environment on the reaction, and the isocyanate siloxane is added to the high-level reactor containing the polyester polyol, thereby ensuring the normal progress of the subsequent reaction.

[0031] Beneficial effects:

[0032] 1. The present invention adopts a crystalline polyester polyol formed by polycondensation of a straight-chain dicarboxylic acid and a diol containing side methyl groups, so that the adhesive prepared therefrom has good flexibility, which is more conducive to the softness of the reflective hydrophobic fabric.

[0033] 2. In the present invention, when the polyester polyol is limited to have a number average molecular weight of 2000 g / mol, the adhesive prepared therefrom has excellent adhesion, thereby increasing the water-resistant performance of the reflective hydrophobic fabric.

[0034] 3. The present invention limits the weight ratio of polyester polyol to isocyanate siloxane to 20: (3-8), so that the adhesive can be well dispersed on the reflective hydrophobic fabric, so that the quality of the reflective hydrophobic fabric obtained is relatively high, and the water resistance performance is also improved.

[0035] 4. The present invention ensures that the reaction proceeds smoothly by strictly controlling the reaction temperature in step (1) within the range of 110 to 120°C.

[0036] 5. The present invention controls the dehydration in step (1) to a water content of less than 500 ppm, thus reaching a predetermined standard, thereby ensuring the smooth progress of the subsequent reaction and the quality of the final product. At the same time, the reaction system is protected by nitrogen, which can reduce the impact of the external environment on the reaction. DETAILED DESCRIPTION

[0037] Example

[0038] Example 1

[0039] Example 1 of the present invention provides a silane-modified polyester prepolymer, wherein the raw materials include: 100 parts of the polyester polyol and 30 parts of isocyanate siloxane in parts by weight.

[0040] The number average molecular weight of the polyester polyol in this embodiment is 2,000.

[0041] The polyester polyol in this embodiment is poly(2-methylpropanediol adipate).

[0042] The isocyanate silane in this embodiment is 3-isocyanate propylmethyldiethoxysilane.

[0043] The preparation method of a silane-modified polyester prepolymer in this embodiment mainly comprises the following steps:

[0044] (1) adding polyester polyol to a high-position reactor, heating, vacuuming and dehydrating, cooling, and introducing nitrogen;

[0045] (2) adding isocyanate siloxane and reacting for 3 hours to obtain a silane-modified polyester prepolymer.

[0046] In this embodiment, the heating temperature in step (1) is 115°C;

[0047] In this embodiment, the vacuum degree in step (1) is -0.095 MPa;

[0048] In this embodiment, the step (1) is dehydrating to a water content of 300 ppm;

[0049] In this embodiment, the cooling temperature in step (1) is 50°C.

[0050] Example 2

[0051] Example 1 of the present invention provides a silane-modified polyester prepolymer, wherein the raw materials include: 100 parts of the polyester polyol and 40 parts of isocyanate siloxane in parts by weight.

[0052] The number average molecular weight of the polyester polyol in this embodiment is 2,000.

[0053] The polyester polyol in this embodiment is poly(2-methylpropanediol adipate).

[0054] The isocyanate silane in this embodiment is 3-isocyanate propylmethyldiethoxysilane.

[0055] The preparation method of a silane-modified polyester prepolymer in this embodiment mainly comprises the following steps:

[0056] (1) adding polyester polyol to a high-position reactor, heating, vacuuming and dehydrating, cooling, and introducing nitrogen;

[0057] (2) adding isocyanate siloxane and reacting for 3 hours to obtain a silane-modified polyester prepolymer.

[0058] In this embodiment, the heating temperature in step (1) is 115°C;

[0059] In this embodiment, the vacuum degree in step (1) is -0.095 MPa;

[0060] In this embodiment, the step (1) is dehydrating to a water content of 500 ppm;

[0061] In this embodiment, the cooling temperature in step (1) is 70°C.

[0062] Example 3

[0063] Example 1 of the present invention provides a silane-modified polyester prepolymer, wherein the raw materials include, by weight: 100 parts of the polyester polyol and 15 parts of isocyanate siloxane.

[0064] The number average molecular weight of the polyester polyol in this embodiment is 2,000.

[0065] The polyester polyol in this embodiment is poly(2-methylpropanediol adipate).

[0066] The isocyanate silane in this embodiment is 3-isocyanate propylmethyldiethoxysilane.

[0067] The preparation method of a silane-modified polyester prepolymer in this embodiment mainly comprises the following steps:

[0068] (1) adding polyester polyol to a high-position reactor, heating, vacuuming and dehydrating, cooling, and introducing nitrogen;

[0069] (2) adding isocyanate siloxane and reacting for 3 hours to obtain a silane-modified polyester prepolymer.

[0070] In this embodiment, the heating temperature in step (1) is 120°C;

[0071] In this embodiment, the vacuum degree in step (1) is -0.09 MPa;

[0072] In this embodiment, the step (1) is dehydrating to a water content of 500 ppm;

[0073] In this embodiment, the cooling temperature in step (1) is 70°C.

[0074] Performance test data:

[0075] Take a small amount of ethyl acetate, aluminum paste and calcium carbonate, pre-disperse them first, then add the silane-modified polyester prepolymer and resin adhesive prepared in Example 1 respectively to prepare the corresponding composite adhesive. Then apply it on the reflective bead-planting film, dry it and hot-press it with the hydrophobic cloth to obtain the reflective hydrophobic cloth. The composite adhesive, by weight, contains at least 20 parts of ethyl acetate, 5 parts of aluminum paste, 8 parts of calcium carbonate, 3 parts of silane-modified polyester prepolymer, and 60 parts of resin adhesive.

[0076] Table 1 shows the performance test results of the improved reflective hydrophobic fabric prepared in Example 1 and the reflective hydrophobic fabric before improvement.

[0077] Table 1

[0078]

[0079]

Claims

1. A silane-modified polyester prepolymer, characterized in that: By weight, the raw materials are composed of 100 parts of polyester polyol and 30 parts of isocyanate siloxane. The number average molecular weight of the polyester polyol is 2000, The polyester polyol is poly(2-methylpropanediol adipate), The isocyanate silane is 3-isocyanate propylmethyldiethoxysilane, The preparation method of the silane-modified polyester prepolymer mainly comprises the following steps: (1) adding polyester polyol to a high-position reactor, heating, vacuuming and dehydrating, cooling, and introducing nitrogen; (2) adding isocyanate siloxane and reacting for 3 hours to obtain a silane-modified polyester prepolymer. The heating temperature in step (1) is 115° C. The vacuum degree of step (1) is -0.095 MPa; The step (1) is dehydrating to a water content of 300 ppm; The cooling temperature in step (1) is 50°C.

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