阅读说明：本技术 一种星型耐高温尼龙及其制备方法和用途 (Star-shaped high-temperature-resistant nylon and preparation method and application thereof ) 是由 邓慧 高敬民 刘浩宇 于 2019-08-23 设计创作，主要内容包括：本发明提供一种星型耐高温尼龙及其制备方法和用途,所述星型耐高温尼龙包括结构式如A或B所示的结构。与相对分子质量相同的线性耐高温尼龙相比,其具有较低的结晶度、高流动性、较小的熔融黏度、流体动力学体积小等特点,同时具有较高的玻璃化转变温度、较高的成炭率和优异的阻燃性能。(The invention provides star-shaped high-temperature-resistant nylon and a preparation method and application thereof. Compared with linear high-temperature resistant nylon with the same relative molecular mass, the high-temperature resistant nylon has the characteristics of lower crystallinity, high fluidity, smaller melt viscosity, small hydrodynamic volume and the like, and simultaneously has higher glass transition temperature, higher char forming rate and excellent flame retardant property.)

1. The star-shaped high-temperature-resistant nylon is characterized by comprising a structure shown as a structural formula A or B:

wherein X is selected from the following structures:

y is selected from the following structures:

2. the star-shaped high temperature resistant nylon of claim 1, wherein the wavy line in the structural formula A or B comprises a repeating structural unit represented by the following general formula (M) and/or a repeating structural unit represented by the following general formula (N);

wherein a is a positive integer of 4 or more, preferably 6, 10 or 12; b is 5 or 11.

3. The star-shaped high temperature resistant nylon according to claim 1, wherein the melt index of the star-shaped high temperature resistant nylon is (80-110) g/10 min.

4. The preparation method of the star-shaped high-temperature-resistant nylon disclosed by any one of claims 1-3 comprises the following steps:

carrying out copolymerization reaction on polybasic acid shown as a structural formula I or II, semi-aromatic nylon salt, lactam, water and a capping agent;

5. the method for preparing star-shaped high temperature resistant nylon according to claim 4, wherein the semi-aromatic nylon salt is one or more selected from the group consisting of a salified product of hexamethylenediamine and terephthalic acid, a salified product of hexamethylenediamine and isophthalic acid, a salified product of decamethylenediamine and terephthalic acid, and a salified product of dodecanediamine and terephthalic acid.

6. The method for preparing the star-shaped high temperature resistant nylon according to claim 4, wherein the method comprises one or two of the following characteristics:

the lactam is one or two selected from caprolactam and laurolactam;

the mass ratio of the semi-aromatic nylon salt to the lactam is (55-75) to (25-45);

the addition amount of the polybasic acid shown in the structural formula I or II is 0.1-5 wt% of the total mass of the semi-aromatic nylon salt and the lactam.

7. The preparation method of the star-shaped high temperature resistant nylon according to claim 4, characterized in that the copolymerization reaction is sequentially divided into three stages according to the control conditions of temperature and pressure:

the first stage is as follows: adding polybasic acid with star structure characteristics, semi-aromatic nylon salt, lactam, water and an end-capping reagent into a reaction kettle, wherein the reaction temperature is 180-240 ℃, the preferable temperature is 190-210 ℃, and the reaction pressure is 1.5-2.5 MPa;

and a second stage: the reaction temperature is 280-330 ℃, preferably 300-320 ℃, and the reaction pressure is 1.5-2.0 MPa;

and a third stage: the reaction temperature is 280-330 ℃, preferably 300-320 ℃, the vacuum is realized, and the reaction pressure is-0.03-0.07 MPa.

8. The method for preparing the star-shaped high temperature resistant nylon according to claim 4, wherein the addition amount of the water is 2-15 wt% of the total mass of the semi-aromatic nylon salt and the lactam.

9. The method for preparing the star-shaped high temperature resistant nylon according to claim 4, wherein the method comprises one or two of the following characteristics:

the end capping agent is one or more selected from benzoic acid, acetic acid, propionic acid and terephthalic acid;

the addition amount of the end-capping agent is 0.1-1 wt% of the total mass of the semi-aromatic nylon salt and the lactam.

10. Use of the star-shaped high temperature resistant nylon according to any one of claims 1 to 3 in automobile engine peripheral parts.

Technical Field

The invention relates to the field of high polymer materials, in particular to star-shaped high-temperature-resistant nylon.

Background

Polyamide (PA), commonly known as nylon, is a generic name for resins containing recurring amide groups in the molecular chain. The nylon is the basic resin with the maximum yield, the maximum variety, the widest application and the excellent comprehensive performance in five general engineering plastics. The high-temperature resistant nylon is nylon engineering plastic which can be used at the temperature of more than 150 ℃ for a long time. The high-temperature resistant nylon has good wear resistance, heat resistance, oil resistance and chemical resistance, greatly reduces the water absorption rate and shrinkage rate of raw materials, and has excellent dimensional stability and excellent mechanical strength. The varieties which are industrialized at present are PA46, PA6T, PA9T and the like. The Dutch DSM company in 1990 realizes the industrialization of the high temperature resistant nylon PA46 for the first time, and pulls open the curtain of the high temperature nylon research.

In order to improve the melt flowability of nylon resins, it is possible to achieve both physical blending and copolymerization. The physical blending method is to blend the high-fluidity additive and the nylon resin by a screw, and the mechanical property of the nylon resin is greatly reduced due to the large addition amount of the additive. The copolymerization method comprises the steps of taking a branched modifier as a copolymerization component to participate in nylon polymerization, introducing a branched structural unit into a nylon molecular chain, reducing the chain entanglement probability and the hydrodynamic volume of the nylon resin under a melting condition, improving the melt fluidity of the nylon resin, and keeping the mechanical property basically unchanged. For example, patent CN101148507A discloses a method for synthesizing hyperbranched nylon 6, which utilizes the copolymerization of dendrimer polyamide-amine (PAMAM) and caprolactam to prepare hyperbranched nylon 6 with melt fluidity 2-3 times that of ordinary nylon 6 with similar mechanical properties. However, because the dendrimer Polyamidoamine (PAMAM) has poor thermal stability and more side reactions at high temperature, when the dendrimer Polyamidoamine (PAMAM) is used as a branching modifier in the high-temperature melt polycondensation process of nylon, the polyamidoamine needs to be salified first, and polymerization process parameters, such as ring opening temperature, short reaction time and complex polymerization process, are strictly controlled.

Disclosure of Invention

In view of the shortcomings of the prior art, the invention aims to provide a star-shaped high-temperature-resistant nylon, a preparation method and application thereof, which are used for solving the problems in the prior art.

To achieve the above objects and other related objects, the present invention is achieved by the following technical solutions.

The invention provides star-shaped high-temperature-resistant nylon which comprises a structure shown as a structural formula A or B:

wherein X is selected from the following structures:

y is selected from the following structures:

according to the technical scheme of the invention, the wavy line in the structural formula A or B comprises a repeating structural unit shown in the following general formula (M) and/or a repeating structural unit shown in the following general formula (N);

wherein a is a positive integer of 4 or more, preferably 6, 10 or 12; b is 5 or 11.

According to the technical scheme of the application, when X isWhen in structure, the wave line in the structural formula A comprises a repeating structural unit shown as a general formula MWherein a is 6, 10 or 12.

According to the technical scheme of the application, when X isWhen in structure, the wave line in the structural formula A comprises a repeating structural unit shown as a general formula NWherein b is 5 or 11.

According to the technical scheme of the application, when X isWhen the structure is shown, the wave line in the structural formula A comprises repeating structural units shown in a general formula M and a general formula NAndwherein a is 6, 10 or 12; b is 5 or 11.

According to the technical scheme of the application, when X isWhen in structure, the wave line in the structural formula A comprises a repeating structural unit shown as a general formula MWherein a is 6, 10 or 12.

According to the technical scheme of the application, when X isWhen in structure, the wave line in the structural formula A comprises a repeating structural unit shown as a general formula NWherein b is 5 or 11.

According to the technical scheme of the application, when X isWhen the structure is shown, the wave line in the structural formula A comprises repeating structural units shown in a general formula M and a general formula NAndwherein a is 6, 10 or 12; b is 5 or 11.

According to the technical scheme of the application, when X isWhen in structure, the wave line in the structural formula A comprises a repeating structural unit shown as a general formula MWherein a is 6, 10 or 12.

According to the technical scheme of the application, when X isWhen in structure, the wave line in the structural formula A comprises a repeating structural unit shown as a general formula NWherein b is 5 or 11.

According to the technical scheme of the application, when X isWhen the structure is shown, the wave line in the structural formula A comprises repeating structural units shown in a general formula M and a general formula NAndwherein a is 6, 10 or 12; b is 5 or 11.

According to the technical scheme of the application, when X isWhen in structure, the wave line in the structural formula A comprises a repeating structural unit shown as a general formula MWherein a is 6, 10 or 12.

According to the technical scheme of the application, when X isWhen in structure, the wave line in the structural formula A comprises a repeating structural unit shown as a general formula NWherein b is 5 or 11.

According to the technical scheme of the application, when X isWhen the structure is shown, the wave line in the structural formula A comprises repeating structural units shown in a general formula M and a general formula NAndwherein a is 6, 10 or 12; b is 5 or 11.

According to the technical scheme of the application, when X isWhen in structure, the wave line in the structural formula A comprises a repeating structural unit shown as a general formula MWherein a is 6, 10 or 12.

According to the technical scheme of the application, when X isWhen in structure, the wave line in the structural formula A comprises a repeating structural unit shown as a general formula NWherein b is 5 or 11.

According to the technical scheme of the application, when X isWhen the structure is shown, the wave line in the structural formula A comprises repeating structural units shown in a general formula M and a general formula NAndwherein a is 6, 10 or 12; b is 5 or 11.

According to the technical scheme of the application, when X isWhen in structure, the wave line in the structural formula A comprises a repeating structural unit shown as a general formula MWherein a is 6, 10 or 12.

According to the technical scheme of the application, when X isWhen in structure, the wave line in the structural formula A comprises a repeating structural unit shown as a general formula NWherein b is 5 or 11.

According to the technical scheme of the application, when X isWhen the structure is shown, the wave line in the structural formula A comprises repeating structural units shown in a general formula M and a general formula NAndwherein a is 6, 10 or 12; b is 5 or 11.

According to the technical scheme of the application, when X isWhen in structure, the wave line in the structural formula A comprises a repeating structural unit shown as a general formula MWherein a is 6, 10 or 12.

According to the technical scheme of the application, when X isWhen in structure, the wave line in the structural formula A comprises a repeating structural unit shown as a general formula NWherein b is 5 or 11.

According to the technical scheme of the application, when X isWhen the structure is shown, the wave line in the structural formula A comprises repeating structural units shown in a general formula M and a general formula NAndwherein a is 6, 10 or 12; b is 5 or 11.

According to the technical scheme of the application, when X isWhen in structure, the wave line in the structural formula A comprises a repeating structural unit shown as a general formula MWherein a is 6, 10 or 12.

According to the technical scheme of the application, when X isWhen in structure, the wave line in the structural formula A comprises a repeating structural unit shown as a general formula NWherein b is 5 or 11.

According to the technical scheme of the application, when X isWhen the structure is shown, the wave line in the structural formula A comprises repeating structural units shown in a general formula M and a general formula NAndwherein a is 6, 10 or 12; b is 5 or 11.

According to the technical scheme of the application, when X isWhen in structure, the wave line in the structural formula A comprises a repeating structural unit shown as a general formula MWherein a is 6, 10 or 12.

According to the technical scheme of the application, when X isWhen in structure, the wave line in the structural formula A comprises a repeating structural unit shown as a general formula NWherein b is 5 or 11.

According to the technical scheme of the application, when X isWhen the structure is shown, the wave line in the structural formula A comprises repeating structural units shown in a general formula M and a general formula NAndwherein a is 6, 10 or 12; b is 5 or 11.

According to the technical scheme of the application, when Y isWhen in structure, the wave line in the structural formula B comprises a repeating structural unit shown as a general formula MWherein a is 6, 10 or 12.

According to the technical scheme of the application, when Y isWhen in structure, the wave line in the structural formula B comprises a repeating structural unit shown as a general formula NWherein b is 5 or 11.

According to the technical scheme of the application, when Y isWhen the structure is shown, the wave line in the structural formula B comprises repeating structural units shown in a general formula M and a general formula NAndwherein a is 6, 10 or 12; b is 5 or 11.

According to the technical scheme of the application, when Y isWhen in structure, the wave line in the structural formula B comprises a repeating structural unit shown as a general formula MWherein a is 6, 10 or 12.

According to the technical scheme of the application, when Y isWhen in structure, the wave line in the structural formula B comprises a repeating structural unit shown as a general formula NWherein b is 5 or11。

According to the technical scheme of the application, when Y isWhen the structure is shown, the wave line in the structural formula B comprises repeating structural units shown in a general formula M and a general formula NAndwherein a is 6, 10 or 12; b is 5 or 11.

According to the technical scheme of the application, when Y isWhen in structure, the wave line in the structural formula B comprises a repeating structural unit shown as a general formula MWherein a is 6, 10 or 12.

According to the technical scheme of the application, when Y isWhen in structure, the wave line in the structural formula B comprises a repeating structural unit shown as a general formula NWherein b is 5 or 11.

According to the technical scheme of the application, when Y isWhen the structure is shown, the wave line in the structural formula B comprises repeating structural units shown in a general formula M and a general formula NAndwherein a is 6, 10 or12; b is 5 or 11.

According to the technical scheme of the application, when Y isWhen in structure, the wave line in the structural formula B comprises a repeating structural unit shown as a general formula MWherein a is 6, 10 or 12.

According to the technical scheme of the application, when Y isWhen in structure, the wave line in the structural formula B comprises a repeating structural unit shown as a general formula NWherein b is 5 or 11.

According to the technical scheme of the application, when Y isWhen the structure is shown, the wave line in the structural formula B comprises repeating structural units shown in a general formula M and a general formula NAndwherein a is 6, 10 or 12; b is 5 or 11.

According to the technical scheme of the invention, the melt index of the star-shaped high-temperature-resistant nylon is (80-110) g/10 min. The test conditions were 320 ℃ and 2.16 kg.

The invention also discloses a preparation method of the star-shaped high-temperature-resistant nylon, which comprises the following steps:

the polybasic acid shown as a structural formula I or II, the semi-aromatic nylon salt, the lactam, the water and the end capping agent are subjected to copolymerization reaction.

According to the technical scheme of the method, the polybasic acid is shown as a structural formula I or II:

wherein X is selected from the following structures:

y is selected from the following structures;

according to the technical scheme of the method, the semi-aromatic nylon salt is one or more selected from 6T salt (salified product of hexamethylene diamine and terephthalic acid), 6I salt (salified product of hexamethylene diamine and isophthalic acid), 10T salt (salified product of decamethylene diamine and terephthalic acid), 12T salt (salified product of dodecane diamine and terephthalic acid), and is preferably 6T salt.

According to the technical scheme of the method, the lactam is one or two selected from caprolactam and laurolactam, and is preferably caprolactam.

According to the technical scheme of the method, the mass ratio of the semi-aromatic nylon salt to the lactam is (55-75): 25-45.

According to the technical scheme of the method, the addition amount of the polybasic acid shown in the structural formula I or II is 0.1-5 wt% of the total mass of the semi-aromatic nylon salt and the lactam.

According to the technical scheme of the method, the initiator required by the reaction medium and the lactam ring-opening reaction is water.

According to the technical scheme of the method, the addition amount of the water is 2-15 wt% of the total mass of the semi-aromatic nylon salt and the lactam.

According to the technical scheme of the method, the end-capping reagent is one or more selected from benzoic acid, acetic acid, propionic acid and terephthalic acid.

According to the technical scheme of the method, the addition amount of the end-capping agent is 0.1-1 wt% of the total mass of the semi-aromatic nylon salt and the lactam.

According to the technical scheme of the method, the copolymerization time is at least 2 h.

According to the technical scheme of the method, the copolymerization reaction is sequentially divided into three stages according to the control conditions of temperature and pressure:

the first stage is as follows: adding polybasic acid with star structure characteristics, semi-aromatic nylon salt, lactam, water and an end-capping reagent into a reaction kettle, wherein the reaction temperature is 180-240 ℃, the preferable temperature is 190-210 ℃, and the reaction pressure is 1.5-2.5 MPa;

and a second stage: the reaction temperature is 280-330 ℃, preferably 300-320 ℃, and the reaction pressure is 1.5-2.0 MPa;

and a third stage: the reaction temperature is 280-330 ℃, preferably 300-320 ℃, the vacuum is realized, and the reaction pressure is-0.03-0.07 MPa.

The invention also discloses the application of the star-shaped high-temperature-resistant nylon in peripheral parts of an automobile engine, such as an exhaust control element, an oil filter, an engine and starter shell and the like, so that the thin wall of a part is realized, and simultaneously, the toughness and the rigidity are considered.

The invention also discloses the application of the star-shaped high-temperature-resistant nylon in the miniaturization and integration applications of the electronic and electrical industry.

Compared with the prior art, the invention has the beneficial effects that:

(1) the polybasic acid compound with six or eight functionality degrees is introduced into a nylon macromolecular chain, and compared with linear high-temperature-resistant nylon with the same relative molecular mass, the polybasic acid compound has the characteristics of lower crystallinity, high fluidity, smaller melt viscosity, small hydrodynamic volume and the like.

(2) The polybasic acid compound containing a large amount of benzene rings and acylamino is introduced into a nylon macromolecular chain, so that the star-shaped high-temperature-resistant nylon has higher glass transition temperature, higher char yield and excellent flame retardant property.

Drawings

FIG. 1 shows the infrared spectrum of the star-shaped high temperature resistant nylon obtained in example 5.

Detailed Description

The following description of the embodiments of the present invention is provided for illustrative purposes, and other advantages and effects of the present invention will become apparent to those skilled in the art from the present disclosure.

Before the present embodiments are further described, it is to be understood that the scope of the invention is not limited to the particular embodiments described below; it is also to be understood that the terminology used in the examples is for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present invention. Test methods in which specific conditions are not specified in the following examples are generally carried out under conventional conditions or under conditions recommended by the respective manufacturers.

When numerical ranges are given in the examples, it is understood that both endpoints of each of the numerical ranges and any value therebetween can be selected unless the invention otherwise indicated. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In addition to the specific methods, devices, and materials used in the examples, any methods, devices, and materials similar or equivalent to those described in the examples may be used in the practice of the invention in addition to the specific methods, devices, and materials used in the examples, in keeping with the knowledge of one skilled in the art and with the description of the invention.