WO2021218648A1

WO2021218648A1 - Process for polymerizing polyesteramide

Info

Publication number: WO2021218648A1
Application number: PCT/CN2021/087440
Authority: WO
Inventors: 李洋
Original assignee: 成都肆零壹科技有限公司
Priority date: 2020-04-30
Filing date: 2021-04-15
Publication date: 2021-11-04
Also published as: CN111363144A; CN111363144B

Abstract

The present invention provides a process for polymerizing a polyesteramide, characterized by the polymerization raw material comprising in parts by mass: 5-60 parts of polymerization monomers, i.e. a dibasic acid and/or dibasic acid ester; 3-50 parts of a diamine; and 10-90 parts of a reactive dispersion medium, i.e. a polyester and/or polyester amide. The process comprises evenly dispersing the polymerization monomers into the molten reactive dispersion medium, and subjecting same to a polymerization reaction so as to obtain a polyesteramide with a suitable molecular weight. The present invention can significantly improve the production efficiency of the polyesteramide.

Description

Polyesteramide polymerization process

Technical field

The invention relates to the technical field of engineering plastics, in particular to a polymerization process of polyester amide.

Background technique

Polyester and polyamide are widely used engineering plastics, and both have their own advantages. Polyamide has excellent mechanical properties and heat resistance, but because of its high molecular polarity, it is easy to absorb water and cause poor dimensional stability. Polyester also has excellent mechanical properties, but its temperature resistance is not as good as polyamide, and because ester bonds are easier to hydrolyze than amide bonds, polyesters are prone to degradation in long-term humid environments. The ester bond has a lower water absorption rate relative to the amide bond, so polyester has a lower water absorption rate than polyamide and has better dimensional stability. In order to combine the advantages of the two, the copolymer polyester amide of the two has also become an important plastic material.

The current continuous polymerization method of polyester amide usually mixes various monomers in the resin material of the reactor, and then the polymerization reaction takes place, which takes a long time and is not easy to realize continuous production. For example, CN109957107 and CN109134850 both prepare polyester amide in a reactor. In this type of method, the esterification process is slower than the amidation process, which affects the polymerization efficiency, makes the entire polymerization time longer, and the production is not easy to be continuous.

Summary of the invention

Aiming at the shortcomings of traditional polyester amides that it is difficult to produce continuously and the reaction time is long, the present invention provides a polyester amide polymerization process. Taking advantage of the fast reaction rate of amino and carboxylic acid and the high equilibrium constant, a method for continuous production of polyester amide has been developed, which can significantly improve the production efficiency of polyester amide.

In order to achieve the above-mentioned purpose of the invention, the technical solution adopted by the present invention is:

A polyester amide polymerization process. The polymerization raw materials by mass include 5-60 parts of polymerized monomer dibasic acid and/or dibasic acid ester, 3-50 parts of diamine and reactive dispersion medium polyester and/ Or 10-90 parts of polyester amide; the polymerized monomer is uniformly dispersed in a molten reactive dispersion medium, and a polymerization reaction occurs to obtain a polyester amide with a suitable molecular weight.

Adding a certain amount of polyester and/or polyester amide resin to the raw materials, as a reactive dispersion system, can uniformly and stably disperse the dibasic acid and/or dibasic acid ester and diamine in the system. Avoid adding a large amount of water, and save the preparation step of preparing nylon salt in traditional aqueous solution. In addition, due to the addition of polyester and/or polyester amide, the polymerized monomer can be uniformly dispersed in the polyester and/or polyester amide medium, and the dispersion system has a certain melting point and viscosity, which can adapt to the screw extrusion equipment. Application, so that the material mixing and dispersion process can be carried out in the screw extrusion equipment, giving full play to the advantages of high heat transfer and dispersion efficiency of the screw extrusion equipment. In the process of material dispersion, the acid may partially react with the polymer dispersion medium to dissolve in the medium. Part of the unreacted acid is dispersed by the screw extrusion equipment and can also be dispersed in very small particles to ensure The uniformity of the entire system.

The raw materials of the present invention are added to the screw extruder by weight measurement or volume measurement to melt reaction and mix uniformly, and then enter the subsequent polymerization device to complete the continuous polymerization reaction to obtain the polyester amide resin. Realize complete continuous production, which can greatly improve the production efficiency of polyester amide.

Since the viscosity of the dispersion system is higher than that of the traditional nylon salt method, it is not conducive to the mixing of diamines. The dispersion efficiency of the screw extrusion device is much higher than that of the reaction kettle stirring, and the interface update efficiency can reach hundreds of that of the kettle type stirring device. Double, to ensure the uniform mixing of the entire system. The super-high interface update efficiency of the screw extrusion device, and its heat exchange efficiency is also very outstanding. It can quickly raise the temperature of the raw material from a solid to a molten state, and can quickly disperse the reaction heat to prevent local overheating in the system. Therefore, the screw is used Extrusion device, continuous production of polyester amide can greatly improve production efficiency. The most commonly used screw extrusion device is a co-rotating twin-screw extrusion device with conveying and mixing effects, and other screw extrusion devices with the above-mentioned functions can also be applied to the present invention.

Because of the good sealing performance and pressure resistance of the screw equipment, it can be ensured that even if the temperature in the system exceeds the boiling point of the diamine raw material, it can still be mixed well, and there is no restriction on the boiling point of the diamine. The dibasic acid ester is more volatile than the dibasic acid, and the closed mixing and uniform mixing in the screw extrusion device also has advantages over the reaction kettle.

Compared with the esterification reaction, the amidation reaction has a faster speed and a higher equilibrium constant, which can very quickly increase the molecular weight. Because the present invention uses polyester and/or polyester amide raw materials that have completed the esterification reaction, only the amidation reaction is performed in the screw device, so the efficiency can be greatly improved compared to the simultaneous esterification and amidation reactions.

The route of the present invention does not require special preparation of nylon salt in advance, so it is convenient to prepare copolymerized nylon by mixing several dibasic acids or diamines and then feeding, so as to adjust the performance of the product in a larger range. It is even possible to add part of the polyacid or polyamine into the monomer to make the product have a certain degree of cross-linking, thereby improving the temperature resistance of the product.

The above factors are combined to form a set of efficient and environmentally friendly polymerization process. The continuous production of polyester amide realized by the present invention can greatly improve the production efficiency of polyester amide and reduce the cost.

In order to achieve continuous production, a weightless metering device or a continuous volume metering device can be used to ensure the stability and continuity of the addition of each component. Part or all of the raw materials can be mixed according to the proportions before metering.

The weight measurement includes the use of a weightless metering device and a liquid pump metering device, and the volume measurement includes the use of a screw metering device and a liquid pump metering device.

All or part of the polyester and/or polyester amide raw materials of the present invention are first added from the front end of the screw extrusion device. The feeding method of various raw materials of the screw extrusion equipment is very flexible. It can be added at the same time at the head, or part of the raw materials can be added in the middle section of the extrusion equipment by side feeding or liquid pumping, even the same raw material It can be added in batches at different positions to further make the mixing more uniform. However, in order to meet the actual needs of screw extrusion equipment, the first batch of raw materials added to the system must include polyester and/or polyester amide.

The molecular weight of polyester and/or polyester amide raw materials mixed with acid will be very low, which may cause the viscosity to be too low and unsuitable for twin-screw feeding. Replenish high-molecular-weight polyester and/or polyester amide polymerization at the back of the twin-screw The material can make the system viscosity increase, and it is more suitable for twin-screw extrusion.

Preferably, the screw of the screw extruder is divided into a feeding section, a melting and dispersing section and a polymerization section in sequence, the material does not melt in the feeding section, and the temperature of the melting and dispersing section is not lower than polyester and/ Or the melting point of the polyester amide raw material.

In order to ensure the reaction rate and dispersion effect of polyester and/or polyester amide raw materials and monomers, the temperature of each section of the screw extrusion equipment needs to be set differently, and the temperature of the feeding section should not be too high, not exceeding the dispersion medium. Melting point to ensure the smooth delivery of solid raw materials. The temperature of the melting section must ensure that the raw material polyester and/or polyester amide melt to fully disperse the polymerized monomers. The temperature must be higher than the melting point of polyester and/or polyester amide to ensure sufficient Blending effect. Increase the temperature of the polymerization section to a maximum temperature of not less than 250°C, to ensure that the raw materials can react and mix better in the molten state, and to improve the efficiency of polymerization.

Dibasic acid has a higher melting point than diamine, especially when the raw material contains aromatic dibasic acid, it is more difficult to disperse. In terms of operation, it is preferable to put the dibasic acid and polyester and/or polyester amide into the screw from the front end. Extrusion device to disperse dibasic acid into molten polyester and/or polyester amide to form a melted mixture of polyester and/or polyester amide and dibasic acid, and then disperse diamine in liquid form from the melt The section is added to the screw extruder. In order to prevent the diamine from volatilizing before the polyester and/or polyester amide is melted, it is better to add it from the melting and dispersing section; and the diamine is melted into a liquid state and then added to the screw extrusion device, which is easier to ensure the airtightness of the equipment .

Preferably, the polyester and/or polyester amide are first introduced into the screw extrusion device from the front end, and then the dibasic acid ester and the diamine are added into the screw extrusion device from the melt dispersion section in liquid form. Because the dibasic acid ester has a low melting point, it can be added in the melt-dispersing section in liquid form. If it is added at the front end, the temperature of the feed section needs to be lowered, and the utilization rate of the entire equipment will be lower.

Preferably, the dibasic acid and/or dibasic acid ester, diamine and polyester are polymerized to obtain polyester amide, and then the polyester amide is further combined with the dibasic acid and/or dibasic acid ester and The diamine is polymerized to obtain a polyester amide product with a higher amide ratio. The polarity of polyester is low, and the dispersing effect of dibasic acid and/or dibasic acid ester is not very good. The amide can be prepared by repeatedly polymerizing the obtained polyester amide with monomer raw materials and adding monomer raw materials in batches. The higher proportion of polyester amide has a higher melting point.

Although the mixing system obtained by the screw extrusion equipment has good uniformity, the molecular weight is not enough. It is necessary to further increase the molecular weight in the subsequent polymerization equipment to meet the needs of practical applications. The subsequent polymerization device can be directly connected to the screw extrusion device for further polymerization, or can be connected to a pipeline type or a reactor type polymerization device. In view of the better continuous production effect of screw extrusion type and pipeline type polymerization device, the pipeline type and screw type are preferred in the present invention. Extrusion type polymerization device to further increase the molecular weight of the polymer.

The molar ratio of the diamine and the dibasic acid and/or the dibasic acid ester of the present invention is 0.4-2.5:1. In order to obtain a final polymer with a sufficiently large molecular weight, it is necessary to ensure the relative balance of the ratio of amino groups plus hydroxyl and carboxylic acid groups in the final polymerization system. The raw material polyester and/or polyester amide of the present invention can use oligomers with lower molecular weight as raw materials. The content ratio of amino groups plus hydroxyl and carboxyl groups in the oligomer raw materials can be larger. The ratio of the amino group plus the hydroxyl group and the carboxyl group in the raw material is adjusted to the ratio of the acid and the amine raw material, so that the ratio of the acid and the amino hydroxyl group in the final whole system is balanced, and a high molecular weight product is obtained. Therefore, in the present invention, the ratio of acid to amine in the three main raw materials can be adjusted between 0.4-2.5:1, so that the source of the raw materials of the present invention is more extensive. Very primary oligomers can also be used as raw materials. use. The end groups of such oligomers can be mainly amino and hydroxyl groups, or carboxyl groups, or the ratio of amino hydroxyl groups and carboxyl groups can be equivalent, or even primary polymers containing unpolymerized carboxylic acid or amine monomers. . At this time, the amine value, hydroxyl value and acid value of the oligomer can be measured to determine the ratio of additional amine and acid added to the raw material. When the diamine or dibasic acid is excessive in the whole system, the method of the present invention can also be used to prepare amino or carboxyl-terminated polyester amides of various molecular weights. Low molecular weight polyester amide can be used as an important component in polyurethane, epoxy resin, and hot melt adhesive formulations.

The dibasic acid and/or dibasic acid ester raw material of the present invention contains aromatic dibasic acid and/or ester, and the aromatic dibasic acid and/or dibasic acid ester accounts for the total dibasic acid and/or dibasic acid At least 20% of the ester raw material is more advantageous than traditional methods.

Aromatic dibasic acid is a common polymerization monomer used in high temperature resistant polymers, but because of the particularity of the molecular structure, its solubility and melting performance are far worse than aliphatic diacids, so those containing aromatic diacids The preparation of polymers is also more difficult than aliphatic. Since the method of the present invention makes full use of the dispersion advantage of polymer as a dispersion system, and can also take advantage of the high mixing efficiency of screw extrusion equipment, it can well solve a series of problems faced by the polymerization of aromatic diacids, and is particularly suitable for Preparation of polymers containing aromatic diacids, especially products with a high proportion of aromatic raw materials.

The addition of reactive dispersion system polyester and/or polyester amide is very critical to realize the reaction in the screw, because the introduction of polyester and/or polyester amide is not only used as a dispersion system, but also because of its certain molecular weight, which can Makes the system after the raw materials are dispersed have a certain viscosity, which is more suitable for the application of screw extrusion equipment. The proportion of the polyester and/or polyester amide in the mass of the polymerization raw material is greater than 10%, otherwise it is difficult to adapt to the application of screw extrusion equipment. If the polymerized monomer itself melts, the viscosity is low, and the temperature required for the reaction is relatively high. When using the method of the present invention to synthesize polyester amide, the proportion of polyester and/or polyester amide in the raw material is preferably greater than 30%.

The moisture content in the polymerization raw material of the present invention does not exceed 5%, and the introduction of moisture is avoided.

The beneficial effects of the present invention are:

1. The method of the present invention uses polyester that has completed the esterification reaction as the reaction raw material, which can overcome the simultaneous esterification and amidation in the traditional method, and overcomes the shortcoming that the efficiency of the entire reaction is slowed down by the esterification reaction. Improve the production efficiency of polyester amide.

2. Due to the addition of polyester and/or polyester amide resin, the dispersion system has a certain melting point and viscosity, which can be adapted to the application of screw extrusion equipment, so that the material mixing and dispersion process can be carried out in the screw extrusion equipment. Take advantage of the high heat transfer and dispersion efficiency of the screw extrusion equipment to realize continuous production and greatly improve production efficiency.

3. The present invention performs material mixing and dispersion in screw extrusion equipment, because the screw extrusion device has good sealing performance, rapid heat dissipation, adapts to various boiling point diamines, and has high material addition efficiency, which overcomes the conventional molten polyester amide Polymerization is only suitable for diamines with higher boiling points, and the problem of low addition efficiency; you can only change the composition of the raw materials during the metering to realize the switching of products with different monomer ratios, and the production arrangement is more flexible.

4. The polyester amide polymerization process of the present invention uses polyester and/or polyester amide as a reactive dispersing medium to melt and polymerize with dibasic acid or ester and diamine monomers in a screw extrusion equipment. The raw materials are not continuous. Intermittently enter the screw extrusion equipment, complete the polymerization reaction during the flow of material transmission, realize the continuity of feeding, reaction and discharging, overcome the intermittent production shortcomings of traditional reactor technology, and eliminate the need for aqueous solutions. The step of preparing nylon salt in the nylon salt avoids the production of waste liquid in the nylon salt preparation process, and is a green and environmentally friendly polyester amide synthesis method. It has the characteristics of high production efficiency, low energy consumption, energy saving and environmental protection, and is easy to be widely promoted and applied in actual production.

5. The continuous polyester amide polymerization process of the present invention avoids the problem of unstable product quality caused by batch production, and is not affected by factors such as temperature and pH value during the preparation of nylon salt in the aqueous solution. The obtained product has The characteristics of good uniformity and stable quality.

6. The equipment of the present invention adopts screw-pipe-screw production equipment, which truly realizes the continuity of feeding, reaction and discharging, and avoids the problem of space occupied by screw extrusion equipment.

7. The solubility and melting performance of aromatic dibasic acids are far worse than that of aliphatic dibasic acids. Therefore, the preparation of polyester amides containing aromatic dibasic acids is also more difficult than that of aliphatic polyester amides. Because the method of the present invention makes full use of the dispersion advantages of polyester and/or polyester amide as a dispersion system, and can also take advantage of the advantages of high mixing efficiency of screw extrusion equipment, it is particularly suitable for semi-aromatic high-temperature polyamides containing aromatic dibasic acids. Preparation of ester amides.

8. Because the screw extrusion device has good sealing performance and rapid heat dissipation, the dibasic acid ester with a lower boiling point than the dibasic acid can also be used to prepare polyester amide through melt polymerization by the method of the present invention, and because the dibasic acid ester is used When used as a raw material, the removed small-molecule alcohol is easier to be released during devolatilization than water, and the polymerization efficiency is higher than when a dibasic acid is used as a raw material.

Detailed ways

In order to explain the objective technical solutions of the present invention more clearly and in detail, the following further describes the present invention through related embodiments. The following examples only specifically illustrate the implementation method of the present invention, and do not limit the protection scope of the present invention.

Example 1

A polyester amide polymerization process. The polymerization raw materials, by mass, include 5 parts of polymerized monomer dibasic acid, 5 parts of diamine, and 90 parts of reactive dispersion medium polyester; the polymerized monomer is uniformly dispersed to the melt In the reactive dispersion medium, a polymerization reaction takes place to obtain a polyester amide with a suitable molecular weight.

Example 2

A polyester amide polymerization process. The polymerization raw materials by mass include 60 parts of polymerized monomer dibasic acid ester, 30 parts of diamine and 10 parts of reactive dispersion medium polyester; the raw materials are added to the screw extruder by weight measurement. The melting reaction is uniformly mixed out of the device, and then it enters the kettle-type reaction device to complete the continuous polymerization reaction to obtain a polyester amide with a suitable molecular weight.

The dibasic acid ester raw material contains an aromatic dibasic acid ester, and the aromatic dibasic acid ester accounts for 60% of the molar ratio of the dibasic acid ester raw material.

The moisture content in the polymerization raw materials does not exceed 5%.

Example 3

A polyester amide polymerization process. The polymerization raw materials, by mass, include 10 parts of polymerized monomer dibasic acid, 3 parts of diamine, and 15 parts of reactive dispersion medium polyester amide; the raw materials are added to the screw extruder by weight measurement. The melt reaction is uniformly mixed out of the device, and then it enters the subsequent screw extrusion device to complete the continuous polymerization reaction, and then extrudes and granulates from the screw extrusion device to obtain a polyester amide with a suitable molecular weight.

The screw of the screw extruder is divided into a feeding section and a melting and dispersing section in turn, the material does not melt in the feeding section, and the temperature of the melting and dispersing section is not lower than the melting point of the polyester amide raw material.

First put the dibasic acid and polyester amide into the screw extruder from the front end to disperse the dibasic acid into the molten polyester amide to form a molten mixture of polyester amide and dibasic acid, and then put the diamine in liquid form Join the screw extruder from the melting and dispersing section.

The dibasic acid raw material contains aromatic dibasic acid, and the aromatic dibasic acid accounts for 50% of the molar ratio of the dibasic acid and/or the dibasic acid ester raw material.

The moisture content in the polymerization raw materials does not exceed 5%.

Example 4

A polyester amide polymerization process. The polymerization raw materials by mass include 50 parts of polymerized monomer dibasic acid, 50 parts of diamine, and 50 parts of reactive dispersion medium polyester and polyester amide; the raw materials are measured by volume It is added to the screw extruder to melt and mix uniformly, then enters the tubular reaction device to complete the continuous polymerization reaction, and then extrudes and granulates from the screw extruder to obtain a polyester amide with a suitable molecular weight.

The screw of the screw extruder is divided into a feeding section and a melting and dispersing section in sequence, the materials do not melt in the feeding section, and the temperature of the melting and dispersing section is not lower than the melting point of the polyester and polyester amide raw materials.

First put the dibasic acid and part of the polyester and polyester amide into the screw extruder from the front end to disperse the dibasic acid into the molten polyester and polyester amide to form the melting of polyester, polyester amide and dibasic acid Then, add the remaining polyester and polyester amide from the melt-dispersing section to the mixture, and add the diamine in liquid form to the screw extruder from the melt-dispersing section.

The dibasic acid raw material contains aromatic dibasic acid, and the aromatic dibasic acid accounts for 20% of the molar ratio of the dibasic acid raw material.

Example 5

A polyester amide polymerization process. The polymerization raw materials by mass include 50 parts of polymerized monomer dibasic acid ester, 20 parts of diamine and 30 parts of reactive dispersion medium polyester; the raw materials are added to the screw extruder by weight measurement. The melting reaction is uniformly mixed out of the device, and then it is entered into the reactor to complete the continuous polymerization reaction, and then extruded and granulated from the screw extruder to obtain a polyester amide with a suitable molecular weight.

The screw of the screw extruder is divided into a feeding section and a melting and dispersing section in sequence, the material does not melt in the feeding section, and the temperature of the melting and dispersing section is not lower than the melting point of the polyester raw material.

Firstly, the polyester is put into the screw extruder from the front end, and then the dibasic acid ester and the diamine are fed into the screw extruder from the melting and dispersing section in liquid form.

The dibasic acid ester raw material contains an aromatic dibasic acid ester, and the aromatic dibasic acid ester accounts for 80% of the molar ratio of the dibasic acid ester raw material.

Example 6

A polyester amide polymerization process. The polymerization raw materials, by mass, include 45 parts of polymerized monomer dibasic acid, 40 parts of diamine and 20 parts of reactive dispersion medium polyester; the polyester raw material passes through part of the polymerized monomer first The method of weight measurement is added to the screw extruder to melt the reaction and mix uniformly, then enter the reactor to complete the continuous polymerization reaction, and then extrude and granulate from the screw extruder to obtain a polyester amide with a suitable molecular weight; then the polyester amide It is further polymerized with the remaining polymerized monomers to obtain a polyester amide product with a higher amide ratio.

The screw of the screw extruder is divided into a feeding section and a melting and dispersing section in turn, the material does not melt in the feeding section, and the temperature of the melting and dispersing section is not lower than the melting point of the polyester.

First put the dibasic acid and polyester into the screw extruder from the front end to disperse the dibasic acid into the molten polyester to form a molten mixture of polyester and dibasic acid, and then disperse the diamine in liquid form from the melt The section is added to the screw extruder.

Example 7

By weight, 90 parts of polyethylene terephthalate (PET) and 10 parts of terephthalic acid were banned in an internal mixer at 280°C for 15 minutes to obtain a homogeneously mixed product. The product was placed in a reactor equipped with a condensation device. After nitrogen was pumped three times, the material was heated to 280°C again, and 3.6 parts of ethylenediamine, 0.05 part of catalyst, and 0.1 part of antioxidant were added dropwise at 300°C within half an hour. The reaction was carried out for 30 minutes under the conditions, and then the reaction was continued for 15 minutes under the conditions of -0.07MPa, and the material was discharged to obtain a polyester amide product with a melting point of 271°C and a water absorption rate of 0.8%.

Under the same conditions, the PET raw material has a melting point of 255°C and a water absorption rate of 0.6%. PA66 has a melting point of 265°C and a water absorption rate of 2.5%. The obtained polyester amide product has a melting point of 271°C, which is significantly higher than that of polyester, and has a water absorption rate of 0.8% lower than that of nylon PA66, which is close to the melting point. It is a polymer material that can combine the advantages of the two materials.

Example 8

Mix PET and terephthalic acid in a weight ratio of 90:10, and put them into the single-screw extruder from the head through a weightless metering device. Set the screw temperature, the temperature of the feed section is 100-220℃, and the temperature of the melt-dispersion section is 250-310 ℃, and add 3.6 parts of ethylenediamine into the extruder through the liquid pump in the melting and dispersion section. After the materials are melted and mixed uniformly, the materials enter the reactor, and react at 300 ℃ for 0.5 hours, and then react under the vacuum of -0.07MPa. After 15 minutes, it was extruded and pelletized by a screw to obtain a polyester amide resin with a melting point of 270° C. and a water absorption rate of 0.8%.

In this embodiment, compared with the embodiment 5, the screw extruder can directly squeeze the molten mixture into the reactor, eliminating the need for energy consumption caused by re-heating. In addition, the ethylenediamine is continuously added in the screw extruder, which eliminates the process of slow dripping, saves time, improves production efficiency, and the reactor does not require a condensing device, making the device more concise.

Example 9

The polyester amide resin and terephthalic acid prepared in Example 8 were mixed according to a weight ratio of 90:10, and fed into the single-screw extruder from the head through a weight loss metering device. The screw temperature was set, and the temperature of the feeding section was 100-220 ℃, the temperature of the melt-dispersion section is 250-310℃, and 3.6 parts of ethylenediamine is added to the extruder through the liquid pump in the melt-dispersion section. It reacts for another 15 minutes under a vacuum of -0.06MPa, and then is extruded and pelletized by a screw to obtain a polyester amide resin with a melting point of 278° C. and a water absorption rate of 0.9%.

In this example, the polyester amide product of Example 8 is used as a raw material, so that by adding in batches, a polyester amide with a higher amide ratio and a higher melting point can be prepared.

Example 10

Weigh polyethylene terephthalate and dimethyl terephthalate in a weight ratio of 90:20, and pass the dimethyl phthalate and part of the polyethylene terephthalate through a weightless metering device. The head is put into a single screw extruder. Set the screw temperature, the temperature of the feed section is 100-150℃, the temperature of the melt-dispersion section is 250-310℃, and the remaining polyethylene terephthalate and 3.8 parts of ethylenediamine are added to the extrusion section in the melt-dispersion section. After exiting the machine, the temperature of the reaction section of the extruder is maintained at 280-310℃, the total screw length-to-diameter ratio is 60:1, two vacuum exhaust holes are set up, extrusion granulation, continuous production to obtain polyester amide resin, melting point It is 268°C and the water absorption rate is 0.8%.

Example 11

According to 90 parts of polyethylene terephthalate, put into the single screw extruder through the weight loss metering equipment from the die. Set the screw temperature, the temperature of the feeding section is 100-220℃, the temperature of the melting and dispersion section is 250-310℃, and In the melt-dispersing section, 20 parts of dimethyl terephthalate and 3.8 parts of ethylenediamine were added to the extruder successively, and then the temperature of the reaction section of the extruder was maintained at 280-310℃, and the total screw length-to-diameter ratio 60:1, set 2 vacuum exhaust holes, extrusion granulation, continuous production to obtain polyester amide resin, melting point 271℃, water absorption rate 0.8%.

Example 12

Mix polybutylene terephthalate (PBT) and terephthalic acid in a weight ratio of 90:10, and put them into the single-screw extruder from the head through a weight loss metering device. Set the screw temperature, and the temperature of the feed section is 100 -200℃, the temperature of the melt-dispersion section is 250-310℃, and in the melt-dispersion section, 7.8 parts of butanediamine is added to the extruder through the liquid pump, and the material enters the tube with the set temperature of 280-310℃ after the melt is evenly mixed. In the type polymerizer, screw extrusion granulation to obtain a polyester amide resin with a melting point of 255°C and a water absorption rate of 0.6%.

Under the same conditions, the PBT raw material has a melting point of 238°C and a water absorption rate of 0.4%. PA66 has a melting point of 265°C and a water absorption rate of 2.5%. The obtained polyester amide product has a melting point of 267°C, which is significantly higher than that of polyester, and has a water absorption rate of 0.6% lower than that of nylon PA66, which has a close melting point. It is a polymer material that can combine the advantages of the two materials.

Example 13

Mix polybutylene terephthalate (PBT) and dimethyl terephthalate in a weight ratio of 10:40, and put them into the single-screw extruder from the head through a weight loss metering device. Set the screw temperature and feed section The temperature is 100-150℃, the temperature of the melt-dispersion section is 250-310℃, and in the melt-dispersion section, 27 parts of butanediamine is added to the extruder through a liquid pump, and the material enters the set temperature of 380-310 after the melt is uniformly mixed. In a tubular polymerizer at a temperature of ℃, then enter the screw extruder, and set two vacuum exhaust holes to obtain a polyester amide resin with a melting point of 281°C and a water absorption rate of 1.2%.

Example 14

Weigh polycaprolactone and adipic acid according to a ratio of 80:20, put adipic acid and part of polycaprolactone into the twin-screw extruder from the head of the weight loss metering device, set the screw temperature, and set the temperature of the feeding section to 50- 60℃, the temperature of the melt-dispersion section is 180-220℃, and the remaining polycaprolactone and 16 parts of hexamethylene diamine are added to the extruder in the melt-dispersion section, and the temperature is set to 250-280 degrees Celsius after the melting and mixing are uniform. Then enter the screw extruder and set 2 vacuum exhaust holes to obtain a polyester amide resin with a melting point of 80°C, which is 20°C higher than that of polycaprolactone.

Example 15

Mix PET and isophthalic acid in a weight ratio of 90:10, and put them into the single-screw extruder from the head through a weightless metering device. Set the screw temperature, the temperature of the feed section is 100-220℃, and the temperature of the melt-dispersion section is 250-310 ℃, and add 3.6 parts of ethylenediamine into the extruder through the liquid pump in the melting and dispersion section. After the materials are melted and mixed uniformly, the materials enter the reactor, and react at 300 ℃ for 0.5 hours, and then react under the vacuum of -0.07MPa. 15 minutes, extrude and pelletize by screw to obtain polyester amide resin, which is non-crystalline, has a glass transition temperature of 70°C, is a transparent resin, and has a water absorption rate of 0.8%.

Example 16

Mix PET and isophthalic acid and/or succinic acid at a weight ratio of 90:10 to a one-to-one mixture, and put it into the single-screw extruder from the head of the weight-loss metering device. Set the screw temperature, and the temperature of the feed section is 100- 220°C, the temperature of the melt-dispersion section is 250-310°C, and 3.6 parts of ethylenediamine is added to the extruder through the liquid pump in the melt-dispersion section, and the materials enter the reactor after the melt and mix uniformly, and react at 300°C. For 0.5 hours, react for another 15 minutes under a vacuum of -0.07MPa, and pelletize by screw extrusion to obtain a polyester amide resin. The resin does not crystallize and has a glass transition temperature of 62°C. It is a transparent resin with a water absorption rate of 0.9%.

The resin material obtained by the polymerization process of the polyester amide of the present invention has good uniformity and can be used for conventional melt conveying and die discharge. The material strips are smooth and uniform, continuous strips, and the pellets are fully mixed and continuously produced. The product performance is stable and the product qualification rate is high.

In the preparation method of the present invention, one or more additives such as conventional antioxidants, catalysts, toughening agents, molecular weight regulators and lubricants can be added according to needs, or the polymerization reaction can be directly completed without additives. The preparation method is suitable for the synthesis of various polyester amide resins, and is not limited to the types listed in the examples, and has a wide range of applications.

The above-mentioned embodiments only express the specific implementation of the present invention, and the description is more specific and detailed, but it should not be understood as a limitation to the patent scope of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can be made, and these all fall within the protection scope of the present invention.

Claims

A polyester amide polymerization process, which is characterized in that, by mass, the polymerization raw materials include 5-60 parts of polymerized monomer dibasic acid and/or dibasic acid ester, 3-50 parts of diamine and reactive dispersion medium. 10-90 parts of polyester and/or polyester amide; the polymerized monomer is uniformly dispersed in a molten reactive dispersion medium, and a polymerization reaction occurs to obtain a polyester amide with a suitable molecular weight.
The polyester amide polymerization process according to claim 1, characterized in that the raw materials are added to the screw extruder by weight measurement or volume measurement to melt reaction and mix uniformly, and then enter the subsequent polymerization device to complete the continuous polymerization reaction to obtain Polyesteramide resin.
The polyester amide polymerization process according to claim 2, characterized in that all or part of the polyester and/or polyester amide raw materials are first added from the front end of the screw extrusion device.
The polyester amide polymerization process according to claim 2, wherein the screw of the screw extruder is divided into a feeding section and a melting and dispersing section in sequence, and the material does not melt in the feeding section, and the melting The temperature of the dispersion section is not lower than the melting point of the polyester and/or polyester amide raw materials.
The polyester amide polymerization process according to claim 4, characterized in that the dibasic acid, polyester and/or polyester amide are first injected into the screw extruder from the front end to disperse the dibasic acid into the molten polyester and In the polyester amide, a molten mixture of polyester and/or polyester amide and dibasic acid is formed, and the diamine is added to the screw extruder from the melt dispersion section in liquid form.
The polyester amide polymerization process according to claim 4, characterized in that the polyester and/or polyester amide are first fed into the screw extruder from the front end, and then the dibasic acid ester and diamine are melted from the liquid form. The dispersing section is added to the screw extrusion device.
The polymerization process of polyester amide according to claim 4, characterized in that, the dibasic acid and/or dibasic acid ester, diamine and polyester are polymerized to obtain the polyester amide, and then the polyester amide is further Polymerize with the dibasic acid and/or dibasic acid ester and diamine to obtain a polyester amide product with a higher amide ratio.
The polyester amide polymerization process according to claim 2, wherein the subsequent polymerization device is at least one of a screw extrusion device, a tubular reaction device, and a tank reaction device.
The polyester amide polymerization process according to claim 8, characterized in that, after the raw materials are continuously added to the screw extruder, they are then continuously extruded and pelletized through the tubular reaction device and the screw extruder.
The polyester amide polymerization process according to claim 1, wherein the molar ratio of the diamine and the dibasic acid and/or the dibasic acid ester is between 0.4-2.5:1.
The polyester amide polymerization process according to claim 1, characterized in that the dibasic acid and/or dibasic acid ester raw material contains aromatic dibasic acid and/or dibasic acid ester, and aromatic dibasic acid and/or dibasic acid ester The molar ratio of the acid and/or dibasic acid ester to the total dibasic acid and/or dibasic acid ester raw material is at least 20%.
The polyester amide polymerization process according to claim 1, characterized in that the mass ratio of the polyester and/or polyester amide to the polymerization raw material is greater than 10%.