CN115716902A - Organic silicon modified wear-resistant TPU (thermoplastic polyurethane), and preparation method and application thereof - Google Patents

Abstract

The invention belongs to the technical field of thermoplastic polyurethane elastomers, and particularly relates to an organic silicon modified high-wear-resistance TPU, and a preparation method and application thereof. The composite material mainly comprises the following substances in percentage by mass: 45-65% polymer polyol; 25-40% of diisocyanate; 6.5 to 15 percent of chain extender; 5-15% of an organosilicon modifier; 2-10% of an initiator. The preparation method comprises the following steps: producing reactive hydroxyl organic silicon modified TPU particles by using a double-screw extruder; and mixing the prepared reactive hydroxyl organic silicon modified TPU particles with an initiator in a molten state to perform a crosslinking reaction to obtain the organic silicon modified TPU. After being filmed by siloxane ester under the action of an initiator, the siloxane ester is gathered on the surface of the TPU, thereby obviously improving the wear resistance, water repellency and antifouling property of the TPU product. The organic silicon modified high-wear-resistance TPU prepared by the invention is mainly applied to shoe material products and can also be applied to industrial applications such as trundles, sealing elements and the like.

Description

Organosilicon modified wear-resistant TPU and its preparation method and application

technical field

The invention belongs to the technical field of thermoplastic polyurethane elastomers, and in particular relates to organosilicon-modified wear-resistant TPU and its preparation method and application.

Background technique

Thermoplastic polyurethane elastomer (TPU) has excellent tensile strength, tensile strength, and aging resistance properties, and is a very mature environmentally friendly chemical material. It has the characteristics of high strength, good toughness, aging resistance and weather resistance that cannot be compared with other plastic materials; it also has many excellent functions such as high waterproof and moisture permeability, windproof, coldproof, antibacterial, mildewproof, warm and anti-ultraviolet. . At present, TPU has been widely used in shoe materials, clothing, toys and other plastic products.

However, because TPU has a linear molecular structure, its performance in wear resistance, solvent resistance, and high temperature resistance is not perfect. However, the above-mentioned properties are exactly what TPU must require in many fields of use, such as safety shoes for industrial mines and casters. , seals and other purposes, must require TPU to have good wear resistance.

Patent CN113861668A discloses a high-refractive-index, high-wear-resistant TPU particle and a preparation method thereof, but the method for preparing wear-resistant TPU is complicated, not environmentally friendly, and has a certain loss to the performance of the TPU itself. Patent CN108034038A discloses a high wear-resistant TPU used for cable shells and its preparation method, but its preparation method is relatively complicated and cannot be mass-produced continuously. Patent CN113637139A discloses an organosilicon-modified TPU composition and its preparation method, but there is a problem in the above-mentioned patent, the organosilicon modifier is added after the TPU particles are melted, which is equivalent to secondary processing, especially in large The performance loss of the TPU will be great during the mass production process.

Therefore, it is an important subject to develop a high wear-resistant TPU material with high wear resistance without loss of processing and mechanical properties.

Contents of the invention

Aiming at the deficiencies of the prior art, the object of the present invention is to provide a silicone-modified wear-resistant TPU; the present invention also provides its preparation method, which is scientific and reasonable, simple and easy; the present invention also provides its application.

The organosilicon-modified wear-resistant TPU of the present invention consists of the following mass fractions:

in:

The sum of the mass fraction of polymer polyol, diisocyanate and chain extender is 100%, and the mass fraction of silicone modifier and initiator is the proportion based on this;

The initiator is a cationic photoinitiator, and the cationic light-emitting initiator is a triaryl siloxane.

The number-average molecular weight of the described polymer polyol is 1000-2000, which is polyethylene adipate diol, polybutylene adipate diol, polyhexamethylene adipate diol, poly Ethylene glycol adipate-butylene glycol ester diol, polybutylene adipate-hexanediol ester diol, polybutylene sebacate glycol ester diol, polyhexamethylene sebacate glycol ester diol Or one or more of polyethylene sebacate diols.

Described diisocyanate is diphenylmethane diisocyanate, p-phenyl diisocyanate, toluene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 1,4-cyclohexyl-diisocyanate or decane- One of 1,10-diisocyanates.

The chain extender is a compound of chain extender 1 and chain extender 2, and the chain extender 1 is ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol and methylpropanediol one or more of them.

The chain extender 2 is trimethylolpropane, and the mass ratio of chain extender 1:chain extender 2 is 9:1.

The silicone modifier is a reactive hydroxyl silicone modifier, preferably dihydroxypolydimethylsiloxane.

A kind of preparation method of organosilicon modified wear-resistant TPU of the present invention, comprises the following steps:

Step 1: Add the polymer polyol, diisocyanate, and chain extender to the dynamic mixer through the pouring metering system according to the formula mass ratio for mixing, and then add the mixed materials to the first stage of the twin-screw granulation system with 14 temperature zones In zone 1, the twin-screw temperature is maintained at 140-220°C, and a certain amount of silicone modifier is added to the 10th zone of the twin-screw granulation system to make the R value of TPU reach 1.01, and then the reactive hydroxyl group is obtained after underwater pelletizing Silicone modified TPU particles;

Step 2: Mix the reactive hydroxyl silicone-modified TPU particles obtained in Step 1 with an initiator in a mixer to undergo a cross-linking reaction to obtain a silicone-modified wear-resistant TPU.

in:

The screw speed described in step 1 is 180-220rmp.

The screw temperature settings described in step 1 are:

Zone 1-3: 160-180°C;

Zone 4-10: 180-220°C;

Zone 11-14: 140-160°C;

Underwater pelletizing temperature: 160-180°C.

The organosilicon-modified wear-resistant TPU prepared by the invention is mainly used in shoe material products, and can also be used in casters, seals and other industrial purposes.

Compared with the prior art, the beneficial effects of the present invention are as follows:

(1) The organosilicon-modified wear-resistant TPU of the present invention uses a reactive hydroxyl organosilicon modifier to modify the TPU, and introduces organosilicon and cross-linkable groups into the molecular chain of the TPU, because The compatibility with the TPU segment is poor, and it will gradually migrate to the surface of the TPU to form an organic silicon layer. This type of TPU is heated to a molten state. In a high-temperature environment, the initiator triggers the cross-linking group to carry out a cross-linking reaction, thereby increasing the easy-processing performance of TPU without losing the processing and mechanical properties of normal TPU. Abrasion resistance and fatigue resistance test capabilities; and solve the problems of short service life and fast wear of existing TPU products under specific working conditions.

(2) The present invention adopts the compounding mode of two kinds of chain extenders to improve the mechanical strength and processability of TPU itself; Adding during processing can trigger the TPU without heating, reducing production costs; the present invention introduces reactive silicone in the process of producing TPU particles, which is different from conventional modification implementation cases where TPU particles are melted and then added. It avoids the loss of the performance of TPU itself by secondary processing, and retains the original performance of TPU. The preparation method is simple, scientific and reasonable, low in cost and high in efficiency, and harmless to operators and the surrounding environment.

(3) The organosilicon-modified wear-resistant TPU prepared by the present invention improves wear resistance and aging resistance, and solves the problems of short service life and fast wear of existing TPU products in special operating environments, and can be widely used It is used in product fields such as shoe soles, casters, and seals.

Detailed ways

All raw materials used in the examples are commercially available unless otherwise specified.

Example 1

A kind of organosilicon modified wear-resistant TPU, raw material and mass fraction thereof are as follows:

The preparation process is as follows:

Step 1: Add polybutylene adipate diol (Mn=2000), diphenylmethane diisocyanate, 1,4-butanediol, and trimethylolpropane into the dynamic After the mixer performs rapid mixing, the mixed material is added to the first zone of the twin-screw granulation system with 14 temperature zones, and a certain amount of dihydroxy polydimethylsiloxane is added to the tenth zone of the twin-screw granulation system Alkanes, so that the R value of TPU reaches 1.01, and then obtain reactive hydroxyl silicone modified TPU particles after underwater pelletizing;

Step 2: Mix the reactive hydroxy silicone-modified TPU particles obtained in Step 1 with triaryl siloxane in a mixer to undergo a cross-linking reaction to obtain a silicone-modified wear-resistant TPU.

The screw speed described in step 1 is 200rmp.

The screw temperature settings described in step 1 are:

Zone 1-3: 170°C;

Zone 4-10: 200°C;

Zone 11-14: 150°C;

Underwater pelletizing temperature: 170°C.

Example 2

A kind of organosilicon modified wear-resistant TPU, raw material and mass fraction thereof are as follows:

The preparation process is as follows:

Step 1: Add polyethylene adipate diol (Mn=2000), isophorone diisocyanate, ethylene glycol, and trimethylolpropane to the dynamic mixer through the pouring metering system according to the formula mass ratio for rapid After mixing, the mixed material is added to the first zone of the twin-screw granulation system with 14 temperature zones, and a quantitative amount of dihydroxypolydimethylsiloxane is added to the tenth zone of the twin-screw granulation system to make the TPU The R value of the product reaches 1.01, and then the reactive hydroxyl silicone modified TPU particles are obtained after underwater pelletizing;

Step 2: Mix the reactive hydroxy silicone-modified TPU particles obtained in Step 1 with triaryl siloxane in a mixer to undergo a cross-linking reaction to obtain a silicone-modified wear-resistant TPU.

The screw speed described in step 1 is 180rmp.

The screw temperature settings described in step 1 are:

Zone 1-3: 160°C;

Zone 4-10: 180°C;

Zone 11-14: 140°C;

Underwater pelletizing temperature: 160°C.

Example 3

A kind of organosilicon modified wear-resistant TPU, raw material and mass fraction thereof are as follows:

The preparation process is as follows:

Step 1: After adding polybutylene adipate diol (Mn=2000), toluene diisocyanate, methylpropylene glycol, and trimethylolpropane to the dynamic mixer through the pouring metering system according to the formula mass ratio for rapid mixing, Add the mixed material to the first zone of the twin-screw granulation system with 14 temperature zones, and add a certain amount of dihydroxypolydimethylsiloxane to the tenth zone of the twin-screw granulation system to make the R value of TPU Reach 1.01, and then obtain reactive hydroxyl silicone modified TPU particles after underwater pelletizing;

Step 2: Mix the reactive hydroxy silicone-modified TPU particles obtained in Step 1 with triaryl siloxane in a mixer to undergo a cross-linking reaction to obtain a silicone-modified wear-resistant TPU.

The screw speed described in step 1 is 220rmp.

The screw temperature settings described in step 1 are:

Zone 1-3: 180°C;

Zone 4-10: 220°C;

Zone 11-14: 160°C;

Underwater pelletizing temperature: 180°C.

Example 4

A kind of organosilicon modified wear-resistant TPU, raw material and mass fraction thereof are as follows:

The preparation process is as follows:

Step 1: Add polyethylene adipate diol (Mn=2000), diphenylmethane diisocyanate, 1,6-hexanediol, and trimethylolpropane dynamically through the pouring metering system according to the formula mass ratio After the mixer performs rapid mixing, the mixed material is added to the first zone of the twin-screw granulation system with 14 temperature zones, and a certain amount of dihydroxy polydimethylsiloxane is added to the tenth zone of the twin-screw granulation system Alkanes, so that the R value of TPU reaches 1.01, and then obtain reactive hydroxyl silicone modified TPU particles after underwater pelletizing;

Step 2: Mix the reactive hydroxy silicone-modified TPU particles obtained in Step 1 with triaryl siloxane in a mixer to undergo a cross-linking reaction to obtain a silicone-modified wear-resistant TPU.

The screw speed described in step 1 is 200rmp.

The screw temperature settings described in step 1 are:

Zone 1-3: 170°C;

Zone 4-10: 200°C;

Zone 11-14: 150°C;

Underwater pelletizing temperature: 170°C.

Comparative example 1

Raw materials and their mass fractions are as follows:

Polybutylene adipate diol (Mn=2000) 58,

Diphenylmethane diisocyanate 32.8,

1,4-butanediol 9.2;

The preparation process is as follows:

After adding polybutylene adipate diol (Mn=2000), diphenylmethane diisocyanate, and 1,4-butanediol to the dynamic mixer through the pouring metering system according to the formula mass ratio for rapid mixing, the mixed Good materials are added to the first zone of the twin-screw granulation system with 14 temperature zones, so that the R value of TPU reaches 1.01, and then TPU pellets are obtained after underwater pelletizing;

Said screw speed is 200rmp.

Described screw temperature is set as:

Zone 1-3: 170°C;

Zone 4-10: 200°C;

Zone 11-14: 150°C;

Underwater pelletizing temperature: 170°C.

Comparative example 2

Raw materials and their mass fractions are as follows:

The preparation process is the same as in Comparative Example 1.

Comparative example 3

Raw materials and their mass fractions are as follows:

The preparation process is as follows:

Step 1: Add polybutylene adipate diol (Mn=2000), diphenylmethane diisocyanate, 1,4-butanediol, and trimethylolpropane into the dynamic After the mixer performs rapid mixing, the mixed material is added to the first zone of the twin-screw granulation system with 14 temperature zones, and then TPU pellets are obtained after underwater pelletizing;

Step 2: Heating the TPU particles prepared in step 1 to a molten state and then mixing them with dihydroxypolydimethylsiloxane, so that the R value of the TPU reaches 1.01;

Step 3: Mix the reactive hydroxyl silicone-modified TPU obtained in step 2 with triaryl silicone ether in a mixer to undergo a cross-linking reaction to obtain a silicone-modified cross-linked TPU.

The screw speed described in step 1 is 200rmp.

The screw temperature settings described in step 1 are:

Zone 1-3: 170°C;

Zone 4-10: 200°C;

Zone 11-14: 150°C;

Underwater pelletizing temperature: 170°C.

Comparative example 4

Raw materials and their mass fractions are as follows:

The preparation process is as follows:

Step 1: Add polybutylene adipate diol (Mn=2000), diphenylmethane diisocyanate, 1,4-butanediol, and trimethylolpropane into the dynamic After the mixer performs rapid mixing, the mixed material is added to the first zone of the twin-screw granulation system with 14 temperature zones, and a certain amount of dihydroxy polydimethylsiloxane is added to the tenth zone of the twin-screw granulation system Alkanes, so that the R value of TPU reaches 1.01, and then obtain reactive hydroxyl silicone modified TPU particles after underwater pelletizing;

Step 2: heating the reactive hydroxy silicone-modified TPU particles obtained in step 1 to a molten state and mixing with benzoyl tert-butyl peroxide to undergo a cross-linking reaction to obtain a silicone-modified cross-linked TPU.

The screw speed described in step 1 is 200rmp.

The screw temperature settings described in step 1 are:

Zone 1-3: 170°C;

Zone 4-10: 200°C;

Zone 11-14: 150°C;

Underwater pelletizing temperature: 170°C.

Comparative example 5

Raw materials and their mass fractions are as follows:

The preparation process is as follows:

Step 1: Add polybutylene adipate diol (Mn=2000), diphenylmethane diisocyanate, and 1,4-butanediol to the dynamic mixer through the pouring metering system according to the formula mass ratio for rapid mixing , the mixed material is added to the first zone of the twin-screw granulation system with 14 temperature zones, and a quantitative amount of dihydroxypolydimethylsiloxane is added to the tenth zone of the twin-screw granulation system to make the R of TPU The value reaches 1.01, and then the reactive hydroxyl silicone modified TPU particles are obtained after underwater pelletizing;

Step 2: Mix the reactive hydroxy silicone-modified TPU particles obtained in Step 1: with triarylsiloxane in a mixer to undergo a cross-linking reaction to obtain a silicone-modified cross-linked TPU.

Test the TPU sample that above-mentioned embodiment and comparative example obtain according to TPU performance test method, the result that obtains is as shown in table 1:

Table 1 Performance comparison between the implementation case and the comparison case

As can be seen from Table 1, the use of compound chain extenders in the present invention can improve the mechanical strength and processing performance of TPU; the organic silicon modifier is added in the TPU twin-screw granulation link, which can effectively avoid the secondary processing of TPU. Add some strength loss; the effect of using photoinitiator on the surface gloss and wear resistance of TPU is obviously better than that of peroxide initiator.

In summary, introducing a reactive silicone modifier into TPU, and then carrying out a crosslinking reaction through the action of a photoinitiator, the silicone modified crosslinked TPU obtained makes TPU easy to process, has excellent wear resistance and Mechanical properties; the production process is simple and easy, and can be widely used in shoe materials, industrial casters, seals and other fields.

Claims (10)

1. A silicone modified wear-resistant TPU is characterized in that it is made of the following mass fractions:

in: The sum of the mass fraction of polymer polyol, diisocyanate and chain extender is 100%, and the mass fraction of silicone modifier and initiator is the proportion based on this; The initiator is a cationic photoinitiator, and the cationic light-emitting initiator is a triaryl siloxane. 2. The organosilicon modified wear-resistant TPU according to claim 1 is characterized in that, described polymer polyol is polyethylene adipate diol, polybutylene adipate diol , Polyhexanediol adipate diol, polyethylene adipate-butylene glycol ester diol, polybutylene adipate-hexanediol ester diol, polybutylene sebacate One or more of diol, polyhexamethylene sebacate diol or polyethylene sebacate diol. 3. The organosilicon-modified wear-resistant TPU according to claim 1, wherein said diisocyanate is diphenylmethane diisocyanate, p-phenylene diisocyanate, toluene diisocyanate, hexamethylene diisocyanate , isophorone diisocyanate, 1,4-cyclohexyl-diisocyanate or decane-1,10-diisocyanate. 4. The organosilicon-modified wear-resistant TPU according to claim 1, wherein the chain extender is a compound of chain extender 1 and chain extender 2, and the chain extender 1 is ethylene glycol , propylene glycol, 1,4-butanediol, 1,6-hexanediol and one or more of methylpropanediol. 5. The silicone-modified wear-resistant TPU according to claim 4, characterized in that the chain extender 2 is trimethylolpropane. 6. The organosilicon-modified wear-resistant TPU according to claim 1, wherein the organosilicon modifier is a reactive hydroxyl organosilicon modifier. 7. A method for preparing the organosilicon-modified wear-resistant TPU described in any one of claims 1-6, characterized in that, comprising the following steps: (1) Add the polymer polyol, diisocyanate, and chain extender to the dynamic mixer through the pouring metering system according to the formula mass ratio for mixing, and then add the mixed materials to the twin-screw granulation system with fourteen temperature zones In the first zone, the twin-screw temperature is kept at 140-220°C. After adding a certain amount of silicone modifier to the 10th zone of the twin-screw granulation system for reaction, it undergoes underwater pelletizing to obtain reactive hydroxyl silicone-modified TPU. particles; (2) Mix the reactive hydroxyl silicone-modified TPU particles obtained in step (1) with an initiator in a mixer to undergo a cross-linking reaction to obtain a silicone-modified wear-resistant TPU. 8. The preparation method of organosilicon-modified wear-resistant TPU according to claim 7, characterized in that, the screw speed in step (1) is 180-220rmp. 9. the preparation method of silicone modified wear-resistant TPU according to claim 7, is characterized in that, the twin-screw temperature described in step (1) is set to: Zone 1-3: 160-180°C; Zone 4-10: 180-220°C; Zone 11-14: 140-160°C; Underwater pelletizing temperature: 160-180°C. 10. An application of the organosilicon-modified wear-resistant TPU according to any one of claims 1-6, characterized in that it is applied to shoe materials, casters, and seals.